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1 /* libFLAC - Free Lossless Audio Codec library
2  * Copyright (C) 2000-2009  Josh Coalson
3  * Copyright (C) 2011-2016  Xiph.Org Foundation
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * - Redistributions of source code must retain the above copyright
10  * notice, this list of conditions and the following disclaimer.
11  *
12  * - Redistributions in binary form must reproduce the above copyright
13  * notice, this list of conditions and the following disclaimer in the
14  * documentation and/or other materials provided with the distribution.
15  *
16  * - Neither the name of the Xiph.org Foundation nor the names of its
17  * contributors may be used to endorse or promote products derived from
18  * this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
24  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
26  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
27  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
28  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
29  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
30  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #ifndef FLAC__STREAM_ENCODER_H
34 #define FLAC__STREAM_ENCODER_H
35 
36 #include <stdio.h> /* for FILE */
37 #include "export.h"
38 #include "format.h"
39 #include "stream_decoder.h"
40 
41 #ifdef __cplusplus
42 extern "C" {
43 #endif
44 
45 
46 /** \file include/FLAC/stream_encoder.h
47  *
48  *  \brief
49  *  This module contains the functions which implement the stream
50  *  encoder.
51  *
52  *  See the detailed documentation in the
53  *  \link flac_stream_encoder stream encoder \endlink module.
54  */
55 
56 /** \defgroup flac_encoder FLAC/ \*_encoder.h: encoder interfaces
57  *  \ingroup flac
58  *
59  *  \brief
60  *  This module describes the encoder layers provided by libFLAC.
61  *
62  * The stream encoder can be used to encode complete streams either to the
63  * client via callbacks, or directly to a file, depending on how it is
64  * initialized.  When encoding via callbacks, the client provides a write
65  * callback which will be called whenever FLAC data is ready to be written.
66  * If the client also supplies a seek callback, the encoder will also
67  * automatically handle the writing back of metadata discovered while
68  * encoding, like stream info, seek points offsets, etc.  When encoding to
69  * a file, the client needs only supply a filename or open \c FILE* and an
70  * optional progress callback for periodic notification of progress; the
71  * write and seek callbacks are supplied internally.  For more info see the
72  * \link flac_stream_encoder stream encoder \endlink module.
73  */
74 
75 /** \defgroup flac_stream_encoder FLAC/stream_encoder.h: stream encoder interface
76  *  \ingroup flac_encoder
77  *
78  *  \brief
79  *  This module contains the functions which implement the stream
80  *  encoder.
81  *
82  * The stream encoder can encode to native FLAC, and optionally Ogg FLAC
83  * (check FLAC_API_SUPPORTS_OGG_FLAC) streams and files.
84  *
85  * The basic usage of this encoder is as follows:
86  * - The program creates an instance of an encoder using
87  *   FLAC__stream_encoder_new().
88  * - The program overrides the default settings using
89  *   FLAC__stream_encoder_set_*() functions.  At a minimum, the following
90  *   functions should be called:
91  *   - FLAC__stream_encoder_set_channels()
92  *   - FLAC__stream_encoder_set_bits_per_sample()
93  *   - FLAC__stream_encoder_set_sample_rate()
94  *   - FLAC__stream_encoder_set_ogg_serial_number() (if encoding to Ogg FLAC)
95  *   - FLAC__stream_encoder_set_total_samples_estimate() (if known)
96  * - If the application wants to control the compression level or set its own
97  *   metadata, then the following should also be called:
98  *   - FLAC__stream_encoder_set_compression_level()
99  *   - FLAC__stream_encoder_set_verify()
100  *   - FLAC__stream_encoder_set_metadata()
101  * - The rest of the set functions should only be called if the client needs
102  *   exact control over how the audio is compressed; thorough understanding
103  *   of the FLAC format is necessary to achieve good results.
104  * - The program initializes the instance to validate the settings and
105  *   prepare for encoding using
106  *   - FLAC__stream_encoder_init_stream() or FLAC__stream_encoder_init_FILE()
107  *     or FLAC__stream_encoder_init_file() for native FLAC
108  *   - FLAC__stream_encoder_init_ogg_stream() or FLAC__stream_encoder_init_ogg_FILE()
109  *     or FLAC__stream_encoder_init_ogg_file() for Ogg FLAC
110  * - The program calls FLAC__stream_encoder_process() or
111  *   FLAC__stream_encoder_process_interleaved() to encode data, which
112  *   subsequently calls the callbacks when there is encoder data ready
113  *   to be written.
114  * - The program finishes the encoding with FLAC__stream_encoder_finish(),
115  *   which causes the encoder to encode any data still in its input pipe,
116  *   update the metadata with the final encoding statistics if output
117  *   seeking is possible, and finally reset the encoder to the
118  *   uninitialized state.
119  * - The instance may be used again or deleted with
120  *   FLAC__stream_encoder_delete().
121  *
122  * In more detail, the stream encoder functions similarly to the
123  * \link flac_stream_decoder stream decoder \endlink, but has fewer
124  * callbacks and more options.  Typically the client will create a new
125  * instance by calling FLAC__stream_encoder_new(), then set the necessary
126  * parameters with FLAC__stream_encoder_set_*(), and initialize it by
127  * calling one of the FLAC__stream_encoder_init_*() functions.
128  *
129  * Unlike the decoders, the stream encoder has many options that can
130  * affect the speed and compression ratio.  When setting these parameters
131  * you should have some basic knowledge of the format (see the
132  * <A HREF="../documentation_format_overview.html">user-level documentation</A>
133  * or the <A HREF="../format.html">formal description</A>).  The
134  * FLAC__stream_encoder_set_*() functions themselves do not validate the
135  * values as many are interdependent.  The FLAC__stream_encoder_init_*()
136  * functions will do this, so make sure to pay attention to the state
137  * returned by FLAC__stream_encoder_init_*() to make sure that it is
138  * FLAC__STREAM_ENCODER_INIT_STATUS_OK.  Any parameters that are not set
139  * before FLAC__stream_encoder_init_*() will take on the defaults from
140  * the constructor.
141  *
142  * There are three initialization functions for native FLAC, one for
143  * setting up the encoder to encode FLAC data to the client via
144  * callbacks, and two for encoding directly to a file.
145  *
146  * For encoding via callbacks, use FLAC__stream_encoder_init_stream().
147  * You must also supply a write callback which will be called anytime
148  * there is raw encoded data to write.  If the client can seek the output
149  * it is best to also supply seek and tell callbacks, as this allows the
150  * encoder to go back after encoding is finished to write back
151  * information that was collected while encoding, like seek point offsets,
152  * frame sizes, etc.
153  *
154  * For encoding directly to a file, use FLAC__stream_encoder_init_FILE()
155  * or FLAC__stream_encoder_init_file().  Then you must only supply a
156  * filename or open \c FILE*; the encoder will handle all the callbacks
157  * internally.  You may also supply a progress callback for periodic
158  * notification of the encoding progress.
159  *
160  * There are three similarly-named init functions for encoding to Ogg
161  * FLAC streams.  Check \c FLAC_API_SUPPORTS_OGG_FLAC to find out if the
162  * library has been built with Ogg support.
163  *
164  * The call to FLAC__stream_encoder_init_*() currently will also immediately
165  * call the write callback several times, once with the \c fLaC signature,
166  * and once for each encoded metadata block.  Note that for Ogg FLAC
167  * encoding you will usually get at least twice the number of callbacks than
168  * with native FLAC, one for the Ogg page header and one for the page body.
169  *
170  * After initializing the instance, the client may feed audio data to the
171  * encoder in one of two ways:
172  *
173  * - Channel separate, through FLAC__stream_encoder_process() - The client
174  *   will pass an array of pointers to buffers, one for each channel, to
175  *   the encoder, each of the same length.  The samples need not be
176  *   block-aligned, but each channel should have the same number of samples.
177  * - Channel interleaved, through
178  *   FLAC__stream_encoder_process_interleaved() - The client will pass a single
179  *   pointer to data that is channel-interleaved (i.e. channel0_sample0,
180  *   channel1_sample0, ... , channelN_sample0, channel0_sample1, ...).
181  *   Again, the samples need not be block-aligned but they must be
182  *   sample-aligned, i.e. the first value should be channel0_sample0 and
183  *   the last value channelN_sampleM.
184  *
185  * Note that for either process call, each sample in the buffers should be a
186  * signed integer, right-justified to the resolution set by
187  * FLAC__stream_encoder_set_bits_per_sample().  For example, if the resolution
188  * is 16 bits per sample, the samples should all be in the range [-32768,32767].
189  *
190  * When the client is finished encoding data, it calls
191  * FLAC__stream_encoder_finish(), which causes the encoder to encode any
192  * data still in its input pipe, and call the metadata callback with the
193  * final encoding statistics.  Then the instance may be deleted with
194  * FLAC__stream_encoder_delete() or initialized again to encode another
195  * stream.
196  *
197  * For programs that write their own metadata, but that do not know the
198  * actual metadata until after encoding, it is advantageous to instruct
199  * the encoder to write a PADDING block of the correct size, so that
200  * instead of rewriting the whole stream after encoding, the program can
201  * just overwrite the PADDING block.  If only the maximum size of the
202  * metadata is known, the program can write a slightly larger padding
203  * block, then split it after encoding.
204  *
205  * Make sure you understand how lengths are calculated.  All FLAC metadata
206  * blocks have a 4 byte header which contains the type and length.  This
207  * length does not include the 4 bytes of the header.  See the format page
208  * for the specification of metadata blocks and their lengths.
209  *
210  * \note
211  * If you are writing the FLAC data to a file via callbacks, make sure it
212  * is open for update (e.g. mode "w+" for stdio streams).  This is because
213  * after the first encoding pass, the encoder will try to seek back to the
214  * beginning of the stream, to the STREAMINFO block, to write some data
215  * there.  (If using FLAC__stream_encoder_init*_file() or
216  * FLAC__stream_encoder_init*_FILE(), the file is managed internally.)
217  *
218  * \note
219  * The "set" functions may only be called when the encoder is in the
220  * state FLAC__STREAM_ENCODER_UNINITIALIZED, i.e. after
221  * FLAC__stream_encoder_new() or FLAC__stream_encoder_finish(), but
222  * before FLAC__stream_encoder_init_*().  If this is the case they will
223  * return \c true, otherwise \c false.
224  *
225  * \note
226  * FLAC__stream_encoder_finish() resets all settings to the constructor
227  * defaults.
228  *
229  * \{
230  */
231 
232 
233 /** State values for a FLAC__StreamEncoder.
234  *
235  * The encoder's state can be obtained by calling FLAC__stream_encoder_get_state().
236  *
237  * If the encoder gets into any other state besides \c FLAC__STREAM_ENCODER_OK
238  * or \c FLAC__STREAM_ENCODER_UNINITIALIZED, it becomes invalid for encoding and
239  * must be deleted with FLAC__stream_encoder_delete().
240  */
241 typedef enum {
242 
243 	FLAC__STREAM_ENCODER_OK = 0,
244 	/**< The encoder is in the normal OK state and samples can be processed. */
245 
246 	FLAC__STREAM_ENCODER_UNINITIALIZED,
247 	/**< The encoder is in the uninitialized state; one of the
248 	 * FLAC__stream_encoder_init_*() functions must be called before samples
249 	 * can be processed.
250 	 */
251 
252 	FLAC__STREAM_ENCODER_OGG_ERROR,
253 	/**< An error occurred in the underlying Ogg layer.  */
254 
255 	FLAC__STREAM_ENCODER_VERIFY_DECODER_ERROR,
256 	/**< An error occurred in the underlying verify stream decoder;
257 	 * check FLAC__stream_encoder_get_verify_decoder_state().
258 	 */
259 
260 	FLAC__STREAM_ENCODER_VERIFY_MISMATCH_IN_AUDIO_DATA,
261 	/**< The verify decoder detected a mismatch between the original
262 	 * audio signal and the decoded audio signal.
263 	 */
264 
265 	FLAC__STREAM_ENCODER_CLIENT_ERROR,
266 	/**< One of the callbacks returned a fatal error. */
267 
268 	FLAC__STREAM_ENCODER_IO_ERROR,
269 	/**< An I/O error occurred while opening/reading/writing a file.
270 	 * Check \c errno.
271 	 */
272 
273 	FLAC__STREAM_ENCODER_FRAMING_ERROR,
274 	/**< An error occurred while writing the stream; usually, the
275 	 * write_callback returned an error.
276 	 */
277 
278 	FLAC__STREAM_ENCODER_MEMORY_ALLOCATION_ERROR
279 	/**< Memory allocation failed. */
280 
281 } FLAC__StreamEncoderState;
282 
283 /** Maps a FLAC__StreamEncoderState to a C string.
284  *
285  *  Using a FLAC__StreamEncoderState as the index to this array
286  *  will give the string equivalent.  The contents should not be modified.
287  */
288 extern FLAC_API const char * const FLAC__StreamEncoderStateString[];
289 
290 
291 /** Possible return values for the FLAC__stream_encoder_init_*() functions.
292  */
293 typedef enum {
294 
295 	FLAC__STREAM_ENCODER_INIT_STATUS_OK = 0,
296 	/**< Initialization was successful. */
297 
298 	FLAC__STREAM_ENCODER_INIT_STATUS_ENCODER_ERROR,
299 	/**< General failure to set up encoder; call FLAC__stream_encoder_get_state() for cause. */
300 
301 	FLAC__STREAM_ENCODER_INIT_STATUS_UNSUPPORTED_CONTAINER,
302 	/**< The library was not compiled with support for the given container
303 	 * format.
304 	 */
305 
306 	FLAC__STREAM_ENCODER_INIT_STATUS_INVALID_CALLBACKS,
307 	/**< A required callback was not supplied. */
308 
309 	FLAC__STREAM_ENCODER_INIT_STATUS_INVALID_NUMBER_OF_CHANNELS,
310 	/**< The encoder has an invalid setting for number of channels. */
311 
312 	FLAC__STREAM_ENCODER_INIT_STATUS_INVALID_BITS_PER_SAMPLE,
313 	/**< The encoder has an invalid setting for bits-per-sample.
314 	 * FLAC supports 4-32 bps but the reference encoder currently supports
315 	 * only up to 24 bps.
316 	 */
317 
318 	FLAC__STREAM_ENCODER_INIT_STATUS_INVALID_SAMPLE_RATE,
319 	/**< The encoder has an invalid setting for the input sample rate. */
320 
321 	FLAC__STREAM_ENCODER_INIT_STATUS_INVALID_BLOCK_SIZE,
322 	/**< The encoder has an invalid setting for the block size. */
323 
324 	FLAC__STREAM_ENCODER_INIT_STATUS_INVALID_MAX_LPC_ORDER,
325 	/**< The encoder has an invalid setting for the maximum LPC order. */
326 
327 	FLAC__STREAM_ENCODER_INIT_STATUS_INVALID_QLP_COEFF_PRECISION,
328 	/**< The encoder has an invalid setting for the precision of the quantized linear predictor coefficients. */
329 
330 	FLAC__STREAM_ENCODER_INIT_STATUS_BLOCK_SIZE_TOO_SMALL_FOR_LPC_ORDER,
331 	/**< The specified block size is less than the maximum LPC order. */
332 
333 	FLAC__STREAM_ENCODER_INIT_STATUS_NOT_STREAMABLE,
334 	/**< The encoder is bound to the <A HREF="../format.html#subset">Subset</A> but other settings violate it. */
335 
336 	FLAC__STREAM_ENCODER_INIT_STATUS_INVALID_METADATA,
337 	/**< The metadata input to the encoder is invalid, in one of the following ways:
338 	 * - FLAC__stream_encoder_set_metadata() was called with a null pointer but a block count > 0
339 	 * - One of the metadata blocks contains an undefined type
340 	 * - It contains an illegal CUESHEET as checked by FLAC__format_cuesheet_is_legal()
341 	 * - It contains an illegal SEEKTABLE as checked by FLAC__format_seektable_is_legal()
342 	 * - It contains more than one SEEKTABLE block or more than one VORBIS_COMMENT block
343 	 */
344 
345 	FLAC__STREAM_ENCODER_INIT_STATUS_ALREADY_INITIALIZED
346 	/**< FLAC__stream_encoder_init_*() was called when the encoder was
347 	 * already initialized, usually because
348 	 * FLAC__stream_encoder_finish() was not called.
349 	 */
350 
351 } FLAC__StreamEncoderInitStatus;
352 
353 /** Maps a FLAC__StreamEncoderInitStatus to a C string.
354  *
355  *  Using a FLAC__StreamEncoderInitStatus as the index to this array
356  *  will give the string equivalent.  The contents should not be modified.
357  */
358 extern FLAC_API const char * const FLAC__StreamEncoderInitStatusString[];
359 
360 
361 /** Return values for the FLAC__StreamEncoder read callback.
362  */
363 typedef enum {
364 
365 	FLAC__STREAM_ENCODER_READ_STATUS_CONTINUE,
366 	/**< The read was OK and decoding can continue. */
367 
368 	FLAC__STREAM_ENCODER_READ_STATUS_END_OF_STREAM,
369 	/**< The read was attempted at the end of the stream. */
370 
371 	FLAC__STREAM_ENCODER_READ_STATUS_ABORT,
372 	/**< An unrecoverable error occurred. */
373 
374 	FLAC__STREAM_ENCODER_READ_STATUS_UNSUPPORTED
375 	/**< Client does not support reading back from the output. */
376 
377 } FLAC__StreamEncoderReadStatus;
378 
379 /** Maps a FLAC__StreamEncoderReadStatus to a C string.
380  *
381  *  Using a FLAC__StreamEncoderReadStatus as the index to this array
382  *  will give the string equivalent.  The contents should not be modified.
383  */
384 extern FLAC_API const char * const FLAC__StreamEncoderReadStatusString[];
385 
386 
387 /** Return values for the FLAC__StreamEncoder write callback.
388  */
389 typedef enum {
390 
391 	FLAC__STREAM_ENCODER_WRITE_STATUS_OK = 0,
392 	/**< The write was OK and encoding can continue. */
393 
394 	FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR
395 	/**< An unrecoverable error occurred.  The encoder will return from the process call. */
396 
397 } FLAC__StreamEncoderWriteStatus;
398 
399 /** Maps a FLAC__StreamEncoderWriteStatus to a C string.
400  *
401  *  Using a FLAC__StreamEncoderWriteStatus as the index to this array
402  *  will give the string equivalent.  The contents should not be modified.
403  */
404 extern FLAC_API const char * const FLAC__StreamEncoderWriteStatusString[];
405 
406 
407 /** Return values for the FLAC__StreamEncoder seek callback.
408  */
409 typedef enum {
410 
411 	FLAC__STREAM_ENCODER_SEEK_STATUS_OK,
412 	/**< The seek was OK and encoding can continue. */
413 
414 	FLAC__STREAM_ENCODER_SEEK_STATUS_ERROR,
415 	/**< An unrecoverable error occurred. */
416 
417 	FLAC__STREAM_ENCODER_SEEK_STATUS_UNSUPPORTED
418 	/**< Client does not support seeking. */
419 
420 } FLAC__StreamEncoderSeekStatus;
421 
422 /** Maps a FLAC__StreamEncoderSeekStatus to a C string.
423  *
424  *  Using a FLAC__StreamEncoderSeekStatus as the index to this array
425  *  will give the string equivalent.  The contents should not be modified.
426  */
427 extern FLAC_API const char * const FLAC__StreamEncoderSeekStatusString[];
428 
429 
430 /** Return values for the FLAC__StreamEncoder tell callback.
431  */
432 typedef enum {
433 
434 	FLAC__STREAM_ENCODER_TELL_STATUS_OK,
435 	/**< The tell was OK and encoding can continue. */
436 
437 	FLAC__STREAM_ENCODER_TELL_STATUS_ERROR,
438 	/**< An unrecoverable error occurred. */
439 
440 	FLAC__STREAM_ENCODER_TELL_STATUS_UNSUPPORTED
441 	/**< Client does not support seeking. */
442 
443 } FLAC__StreamEncoderTellStatus;
444 
445 /** Maps a FLAC__StreamEncoderTellStatus to a C string.
446  *
447  *  Using a FLAC__StreamEncoderTellStatus as the index to this array
448  *  will give the string equivalent.  The contents should not be modified.
449  */
450 extern FLAC_API const char * const FLAC__StreamEncoderTellStatusString[];
451 
452 
453 /***********************************************************************
454  *
455  * class FLAC__StreamEncoder
456  *
457  ***********************************************************************/
458 
459 struct FLAC__StreamEncoderProtected;
460 struct FLAC__StreamEncoderPrivate;
461 /** The opaque structure definition for the stream encoder type.
462  *  See the \link flac_stream_encoder stream encoder module \endlink
463  *  for a detailed description.
464  */
465 typedef struct {
466 	struct FLAC__StreamEncoderProtected *protected_; /* avoid the C++ keyword 'protected' */
467 	struct FLAC__StreamEncoderPrivate *private_; /* avoid the C++ keyword 'private' */
468 } FLAC__StreamEncoder;
469 
470 /** Signature for the read callback.
471  *
472  *  A function pointer matching this signature must be passed to
473  *  FLAC__stream_encoder_init_ogg_stream() if seeking is supported.
474  *  The supplied function will be called when the encoder needs to read back
475  *  encoded data.  This happens during the metadata callback, when the encoder
476  *  has to read, modify, and rewrite the metadata (e.g. seekpoints) gathered
477  *  while encoding.  The address of the buffer to be filled is supplied, along
478  *  with the number of bytes the buffer can hold.  The callback may choose to
479  *  supply less data and modify the byte count but must be careful not to
480  *  overflow the buffer.  The callback then returns a status code chosen from
481  *  FLAC__StreamEncoderReadStatus.
482  *
483  * Here is an example of a read callback for stdio streams:
484  * \code
485  * FLAC__StreamEncoderReadStatus read_cb(const FLAC__StreamEncoder *encoder, FLAC__byte buffer[], size_t *bytes, void *client_data)
486  * {
487  *   FILE *file = ((MyClientData*)client_data)->file;
488  *   if(*bytes > 0) {
489  *     *bytes = fread(buffer, sizeof(FLAC__byte), *bytes, file);
490  *     if(ferror(file))
491  *       return FLAC__STREAM_ENCODER_READ_STATUS_ABORT;
492  *     else if(*bytes == 0)
493  *       return FLAC__STREAM_ENCODER_READ_STATUS_END_OF_STREAM;
494  *     else
495  *       return FLAC__STREAM_ENCODER_READ_STATUS_CONTINUE;
496  *   }
497  *   else
498  *     return FLAC__STREAM_ENCODER_READ_STATUS_ABORT;
499  * }
500  * \endcode
501  *
502  * \note In general, FLAC__StreamEncoder functions which change the
503  * state should not be called on the \a encoder while in the callback.
504  *
505  * \param  encoder  The encoder instance calling the callback.
506  * \param  buffer   A pointer to a location for the callee to store
507  *                  data to be encoded.
508  * \param  bytes    A pointer to the size of the buffer.  On entry
509  *                  to the callback, it contains the maximum number
510  *                  of bytes that may be stored in \a buffer.  The
511  *                  callee must set it to the actual number of bytes
512  *                  stored (0 in case of error or end-of-stream) before
513  *                  returning.
514  * \param  client_data  The callee's client data set through
515  *                      FLAC__stream_encoder_set_client_data().
516  * \retval FLAC__StreamEncoderReadStatus
517  *    The callee's return status.
518  */
519 typedef FLAC__StreamEncoderReadStatus (*FLAC__StreamEncoderReadCallback)(const FLAC__StreamEncoder *encoder, FLAC__byte buffer[], size_t *bytes, void *client_data);
520 
521 /** Signature for the write callback.
522  *
523  *  A function pointer matching this signature must be passed to
524  *  FLAC__stream_encoder_init*_stream().  The supplied function will be called
525  *  by the encoder anytime there is raw encoded data ready to write.  It may
526  *  include metadata mixed with encoded audio frames and the data is not
527  *  guaranteed to be aligned on frame or metadata block boundaries.
528  *
529  *  The only duty of the callback is to write out the \a bytes worth of data
530  *  in \a buffer to the current position in the output stream.  The arguments
531  *  \a samples and \a current_frame are purely informational.  If \a samples
532  *  is greater than \c 0, then \a current_frame will hold the current frame
533  *  number that is being written; otherwise it indicates that the write
534  *  callback is being called to write metadata.
535  *
536  * \note
537  * Unlike when writing to native FLAC, when writing to Ogg FLAC the
538  * write callback will be called twice when writing each audio
539  * frame; once for the page header, and once for the page body.
540  * When writing the page header, the \a samples argument to the
541  * write callback will be \c 0.
542  *
543  * \note In general, FLAC__StreamEncoder functions which change the
544  * state should not be called on the \a encoder while in the callback.
545  *
546  * \param  encoder  The encoder instance calling the callback.
547  * \param  buffer   An array of encoded data of length \a bytes.
548  * \param  bytes    The byte length of \a buffer.
549  * \param  samples  The number of samples encoded by \a buffer.
550  *                  \c 0 has a special meaning; see above.
551  * \param  current_frame  The number of the current frame being encoded.
552  * \param  client_data  The callee's client data set through
553  *                      FLAC__stream_encoder_init_*().
554  * \retval FLAC__StreamEncoderWriteStatus
555  *    The callee's return status.
556  */
557 typedef FLAC__StreamEncoderWriteStatus (*FLAC__StreamEncoderWriteCallback)(const FLAC__StreamEncoder *encoder, const FLAC__byte buffer[], size_t bytes, uint32_t samples, uint32_t current_frame, void *client_data);
558 
559 /** Signature for the seek callback.
560  *
561  *  A function pointer matching this signature may be passed to
562  *  FLAC__stream_encoder_init*_stream().  The supplied function will be called
563  *  when the encoder needs to seek the output stream.  The encoder will pass
564  *  the absolute byte offset to seek to, 0 meaning the beginning of the stream.
565  *
566  * Here is an example of a seek callback for stdio streams:
567  * \code
568  * FLAC__StreamEncoderSeekStatus seek_cb(const FLAC__StreamEncoder *encoder, FLAC__uint64 absolute_byte_offset, void *client_data)
569  * {
570  *   FILE *file = ((MyClientData*)client_data)->file;
571  *   if(file == stdin)
572  *     return FLAC__STREAM_ENCODER_SEEK_STATUS_UNSUPPORTED;
573  *   else if(fseeko(file, (off_t)absolute_byte_offset, SEEK_SET) < 0)
574  *     return FLAC__STREAM_ENCODER_SEEK_STATUS_ERROR;
575  *   else
576  *     return FLAC__STREAM_ENCODER_SEEK_STATUS_OK;
577  * }
578  * \endcode
579  *
580  * \note In general, FLAC__StreamEncoder functions which change the
581  * state should not be called on the \a encoder while in the callback.
582  *
583  * \param  encoder  The encoder instance calling the callback.
584  * \param  absolute_byte_offset  The offset from the beginning of the stream
585  *                               to seek to.
586  * \param  client_data  The callee's client data set through
587  *                      FLAC__stream_encoder_init_*().
588  * \retval FLAC__StreamEncoderSeekStatus
589  *    The callee's return status.
590  */
591 typedef FLAC__StreamEncoderSeekStatus (*FLAC__StreamEncoderSeekCallback)(const FLAC__StreamEncoder *encoder, FLAC__uint64 absolute_byte_offset, void *client_data);
592 
593 /** Signature for the tell callback.
594  *
595  *  A function pointer matching this signature may be passed to
596  *  FLAC__stream_encoder_init*_stream().  The supplied function will be called
597  *  when the encoder needs to know the current position of the output stream.
598  *
599  * \warning
600  * The callback must return the true current byte offset of the output to
601  * which the encoder is writing.  If you are buffering the output, make
602  * sure and take this into account.  If you are writing directly to a
603  * FILE* from your write callback, ftell() is sufficient.  If you are
604  * writing directly to a file descriptor from your write callback, you
605  * can use lseek(fd, SEEK_CUR, 0).  The encoder may later seek back to
606  * these points to rewrite metadata after encoding.
607  *
608  * Here is an example of a tell callback for stdio streams:
609  * \code
610  * FLAC__StreamEncoderTellStatus tell_cb(const FLAC__StreamEncoder *encoder, FLAC__uint64 *absolute_byte_offset, void *client_data)
611  * {
612  *   FILE *file = ((MyClientData*)client_data)->file;
613  *   off_t pos;
614  *   if(file == stdin)
615  *     return FLAC__STREAM_ENCODER_TELL_STATUS_UNSUPPORTED;
616  *   else if((pos = ftello(file)) < 0)
617  *     return FLAC__STREAM_ENCODER_TELL_STATUS_ERROR;
618  *   else {
619  *     *absolute_byte_offset = (FLAC__uint64)pos;
620  *     return FLAC__STREAM_ENCODER_TELL_STATUS_OK;
621  *   }
622  * }
623  * \endcode
624  *
625  * \note In general, FLAC__StreamEncoder functions which change the
626  * state should not be called on the \a encoder while in the callback.
627  *
628  * \param  encoder  The encoder instance calling the callback.
629  * \param  absolute_byte_offset  The address at which to store the current
630  *                               position of the output.
631  * \param  client_data  The callee's client data set through
632  *                      FLAC__stream_encoder_init_*().
633  * \retval FLAC__StreamEncoderTellStatus
634  *    The callee's return status.
635  */
636 typedef FLAC__StreamEncoderTellStatus (*FLAC__StreamEncoderTellCallback)(const FLAC__StreamEncoder *encoder, FLAC__uint64 *absolute_byte_offset, void *client_data);
637 
638 /** Signature for the metadata callback.
639  *
640  *  A function pointer matching this signature may be passed to
641  *  FLAC__stream_encoder_init*_stream().  The supplied function will be called
642  *  once at the end of encoding with the populated STREAMINFO structure.  This
643  *  is so the client can seek back to the beginning of the file and write the
644  *  STREAMINFO block with the correct statistics after encoding (like
645  *  minimum/maximum frame size and total samples).
646  *
647  * \note In general, FLAC__StreamEncoder functions which change the
648  * state should not be called on the \a encoder while in the callback.
649  *
650  * \param  encoder      The encoder instance calling the callback.
651  * \param  metadata     The final populated STREAMINFO block.
652  * \param  client_data  The callee's client data set through
653  *                      FLAC__stream_encoder_init_*().
654  */
655 typedef void (*FLAC__StreamEncoderMetadataCallback)(const FLAC__StreamEncoder *encoder, const FLAC__StreamMetadata *metadata, void *client_data);
656 
657 /** Signature for the progress callback.
658  *
659  *  A function pointer matching this signature may be passed to
660  *  FLAC__stream_encoder_init*_file() or FLAC__stream_encoder_init*_FILE().
661  *  The supplied function will be called when the encoder has finished
662  *  writing a frame.  The \c total_frames_estimate argument to the
663  *  callback will be based on the value from
664  *  FLAC__stream_encoder_set_total_samples_estimate().
665  *
666  * \note In general, FLAC__StreamEncoder functions which change the
667  * state should not be called on the \a encoder while in the callback.
668  *
669  * \param  encoder          The encoder instance calling the callback.
670  * \param  bytes_written    Bytes written so far.
671  * \param  samples_written  Samples written so far.
672  * \param  frames_written   Frames written so far.
673  * \param  total_frames_estimate  The estimate of the total number of
674  *                                frames to be written.
675  * \param  client_data      The callee's client data set through
676  *                          FLAC__stream_encoder_init_*().
677  */
678 typedef void (*FLAC__StreamEncoderProgressCallback)(const FLAC__StreamEncoder *encoder, FLAC__uint64 bytes_written, FLAC__uint64 samples_written, uint32_t frames_written, uint32_t total_frames_estimate, void *client_data);
679 
680 
681 /***********************************************************************
682  *
683  * Class constructor/destructor
684  *
685  ***********************************************************************/
686 
687 /** Create a new stream encoder instance.  The instance is created with
688  *  default settings; see the individual FLAC__stream_encoder_set_*()
689  *  functions for each setting's default.
690  *
691  * \retval FLAC__StreamEncoder*
692  *    \c NULL if there was an error allocating memory, else the new instance.
693  */
694 FLAC_API FLAC__StreamEncoder *FLAC__stream_encoder_new(void);
695 
696 /** Free an encoder instance.  Deletes the object pointed to by \a encoder.
697  *
698  * \param encoder  A pointer to an existing encoder.
699  * \assert
700  *    \code encoder != NULL \endcode
701  */
702 FLAC_API void FLAC__stream_encoder_delete(FLAC__StreamEncoder *encoder);
703 
704 
705 /***********************************************************************
706  *
707  * Public class method prototypes
708  *
709  ***********************************************************************/
710 
711 /** Set the serial number for the FLAC stream to use in the Ogg container.
712  *
713  * \note
714  * This does not need to be set for native FLAC encoding.
715  *
716  * \note
717  * It is recommended to set a serial number explicitly as the default of '0'
718  * may collide with other streams.
719  *
720  * \default \c 0
721  * \param  encoder        An encoder instance to set.
722  * \param  serial_number  See above.
723  * \assert
724  *    \code encoder != NULL \endcode
725  * \retval FLAC__bool
726  *    \c false if the encoder is already initialized, else \c true.
727  */
728 FLAC_API FLAC__bool FLAC__stream_encoder_set_ogg_serial_number(FLAC__StreamEncoder *encoder, long serial_number);
729 
730 /** Set the "verify" flag.  If \c true, the encoder will verify it's own
731  *  encoded output by feeding it through an internal decoder and comparing
732  *  the original signal against the decoded signal.  If a mismatch occurs,
733  *  the process call will return \c false.  Note that this will slow the
734  *  encoding process by the extra time required for decoding and comparison.
735  *
736  * \default \c false
737  * \param  encoder  An encoder instance to set.
738  * \param  value    Flag value (see above).
739  * \assert
740  *    \code encoder != NULL \endcode
741  * \retval FLAC__bool
742  *    \c false if the encoder is already initialized, else \c true.
743  */
744 FLAC_API FLAC__bool FLAC__stream_encoder_set_verify(FLAC__StreamEncoder *encoder, FLAC__bool value);
745 
746 /** Set the <A HREF="../format.html#subset">Subset</A> flag.  If \c true,
747  *  the encoder will comply with the Subset and will check the
748  *  settings during FLAC__stream_encoder_init_*() to see if all settings
749  *  comply.  If \c false, the settings may take advantage of the full
750  *  range that the format allows.
751  *
752  *  Make sure you know what it entails before setting this to \c false.
753  *
754  * \default \c true
755  * \param  encoder  An encoder instance to set.
756  * \param  value    Flag value (see above).
757  * \assert
758  *    \code encoder != NULL \endcode
759  * \retval FLAC__bool
760  *    \c false if the encoder is already initialized, else \c true.
761  */
762 FLAC_API FLAC__bool FLAC__stream_encoder_set_streamable_subset(FLAC__StreamEncoder *encoder, FLAC__bool value);
763 
764 /** Set the number of channels to be encoded.
765  *
766  * \default \c 2
767  * \param  encoder  An encoder instance to set.
768  * \param  value    See above.
769  * \assert
770  *    \code encoder != NULL \endcode
771  * \retval FLAC__bool
772  *    \c false if the encoder is already initialized, else \c true.
773  */
774 FLAC_API FLAC__bool FLAC__stream_encoder_set_channels(FLAC__StreamEncoder *encoder, uint32_t value);
775 
776 /** Set the sample resolution of the input to be encoded.
777  *
778  * \warning
779  * Do not feed the encoder data that is wider than the value you
780  * set here or you will generate an invalid stream.
781  *
782  * \default \c 16
783  * \param  encoder  An encoder instance to set.
784  * \param  value    See above.
785  * \assert
786  *    \code encoder != NULL \endcode
787  * \retval FLAC__bool
788  *    \c false if the encoder is already initialized, else \c true.
789  */
790 FLAC_API FLAC__bool FLAC__stream_encoder_set_bits_per_sample(FLAC__StreamEncoder *encoder, uint32_t value);
791 
792 /** Set the sample rate (in Hz) of the input to be encoded.
793  *
794  * \default \c 44100
795  * \param  encoder  An encoder instance to set.
796  * \param  value    See above.
797  * \assert
798  *    \code encoder != NULL \endcode
799  * \retval FLAC__bool
800  *    \c false if the encoder is already initialized, else \c true.
801  */
802 FLAC_API FLAC__bool FLAC__stream_encoder_set_sample_rate(FLAC__StreamEncoder *encoder, uint32_t value);
803 
804 /** Set the compression level
805  *
806  * The compression level is roughly proportional to the amount of effort
807  * the encoder expends to compress the file.  A higher level usually
808  * means more computation but higher compression.  The default level is
809  * suitable for most applications.
810  *
811  * Currently the levels range from \c 0 (fastest, least compression) to
812  * \c 8 (slowest, most compression).  A value larger than \c 8 will be
813  * treated as \c 8.
814  *
815  * This function automatically calls the following other \c _set_
816  * functions with appropriate values, so the client does not need to
817  * unless it specifically wants to override them:
818  * - FLAC__stream_encoder_set_do_mid_side_stereo()
819  * - FLAC__stream_encoder_set_loose_mid_side_stereo()
820  * - FLAC__stream_encoder_set_apodization()
821  * - FLAC__stream_encoder_set_max_lpc_order()
822  * - FLAC__stream_encoder_set_qlp_coeff_precision()
823  * - FLAC__stream_encoder_set_do_qlp_coeff_prec_search()
824  * - FLAC__stream_encoder_set_do_escape_coding()
825  * - FLAC__stream_encoder_set_do_exhaustive_model_search()
826  * - FLAC__stream_encoder_set_min_residual_partition_order()
827  * - FLAC__stream_encoder_set_max_residual_partition_order()
828  * - FLAC__stream_encoder_set_rice_parameter_search_dist()
829  *
830  * The actual values set for each level are:
831  * <table>
832  * <tr>
833  *  <td><b>level</b></td>
834  *  <td>do mid-side stereo</td>
835  *  <td>loose mid-side stereo</td>
836  *  <td>apodization</td>
837  *  <td>max lpc order</td>
838  *  <td>qlp coeff precision</td>
839  *  <td>qlp coeff prec search</td>
840  *  <td>escape coding</td>
841  *  <td>exhaustive model search</td>
842  *  <td>min residual partition order</td>
843  *  <td>max residual partition order</td>
844  *  <td>rice parameter search dist</td>
845  * </tr>
846  * <tr>  <td><b>0</b></td> <td>false</td> <td>false</td> <td>tukey(0.5)<td>                                     <td>0</td>  <td>0</td> <td>false</td> <td>false</td> <td>false</td> <td>0</td> <td>3</td> <td>0</td> </tr>
847  * <tr>  <td><b>1</b></td> <td>true</td>  <td>true</td>  <td>tukey(0.5)<td>                                     <td>0</td>  <td>0</td> <td>false</td> <td>false</td> <td>false</td> <td>0</td> <td>3</td> <td>0</td> </tr>
848  * <tr>  <td><b>2</b></td> <td>true</td>  <td>false</td> <td>tukey(0.5)<td>                                     <td>0</td>  <td>0</td> <td>false</td> <td>false</td> <td>false</td> <td>0</td> <td>3</td> <td>0</td> </tr>
849  * <tr>  <td><b>3</b></td> <td>false</td> <td>false</td> <td>tukey(0.5)<td>                                     <td>6</td>  <td>0</td> <td>false</td> <td>false</td> <td>false</td> <td>0</td> <td>4</td> <td>0</td> </tr>
850  * <tr>  <td><b>4</b></td> <td>true</td>  <td>true</td>  <td>tukey(0.5)<td>                                     <td>8</td>  <td>0</td> <td>false</td> <td>false</td> <td>false</td> <td>0</td> <td>4</td> <td>0</td> </tr>
851  * <tr>  <td><b>5</b></td> <td>true</td>  <td>false</td> <td>tukey(0.5)<td>                                     <td>8</td>  <td>0</td> <td>false</td> <td>false</td> <td>false</td> <td>0</td> <td>5</td> <td>0</td> </tr>
852  * <tr>  <td><b>6</b></td> <td>true</td>  <td>false</td> <td>tukey(0.5);partial_tukey(2)<td>                    <td>8</td>  <td>0</td> <td>false</td> <td>false</td> <td>false</td> <td>0</td> <td>6</td> <td>0</td> </tr>
853  * <tr>  <td><b>7</b></td> <td>true</td>  <td>false</td> <td>tukey(0.5);partial_tukey(2)<td>                    <td>12</td> <td>0</td> <td>false</td> <td>false</td> <td>false</td> <td>0</td> <td>6</td> <td>0</td> </tr>
854  * <tr>  <td><b>8</b></td> <td>true</td>  <td>false</td> <td>tukey(0.5);partial_tukey(2);punchout_tukey(3)</td> <td>12</td> <td>0</td> <td>false</td> <td>false</td> <td>false</td> <td>0</td> <td>6</td> <td>0</td> </tr>
855  * </table>
856  *
857  * \default \c 5
858  * \param  encoder  An encoder instance to set.
859  * \param  value    See above.
860  * \assert
861  *    \code encoder != NULL \endcode
862  * \retval FLAC__bool
863  *    \c false if the encoder is already initialized, else \c true.
864  */
865 FLAC_API FLAC__bool FLAC__stream_encoder_set_compression_level(FLAC__StreamEncoder *encoder, uint32_t value);
866 
867 /** Set the blocksize to use while encoding.
868  *
869  * The number of samples to use per frame.  Use \c 0 to let the encoder
870  * estimate a blocksize; this is usually best.
871  *
872  * \default \c 0
873  * \param  encoder  An encoder instance to set.
874  * \param  value    See above.
875  * \assert
876  *    \code encoder != NULL \endcode
877  * \retval FLAC__bool
878  *    \c false if the encoder is already initialized, else \c true.
879  */
880 FLAC_API FLAC__bool FLAC__stream_encoder_set_blocksize(FLAC__StreamEncoder *encoder, uint32_t value);
881 
882 /** Set to \c true to enable mid-side encoding on stereo input.  The
883  *  number of channels must be 2 for this to have any effect.  Set to
884  *  \c false to use only independent channel coding.
885  *
886  * \default \c true
887  * \param  encoder  An encoder instance to set.
888  * \param  value    Flag value (see above).
889  * \assert
890  *    \code encoder != NULL \endcode
891  * \retval FLAC__bool
892  *    \c false if the encoder is already initialized, else \c true.
893  */
894 FLAC_API FLAC__bool FLAC__stream_encoder_set_do_mid_side_stereo(FLAC__StreamEncoder *encoder, FLAC__bool value);
895 
896 /** Set to \c true to enable adaptive switching between mid-side and
897  *  left-right encoding on stereo input.  Set to \c false to use
898  *  exhaustive searching.  Setting this to \c true requires
899  *  FLAC__stream_encoder_set_do_mid_side_stereo() to also be set to
900  *  \c true in order to have any effect.
901  *
902  * \default \c false
903  * \param  encoder  An encoder instance to set.
904  * \param  value    Flag value (see above).
905  * \assert
906  *    \code encoder != NULL \endcode
907  * \retval FLAC__bool
908  *    \c false if the encoder is already initialized, else \c true.
909  */
910 FLAC_API FLAC__bool FLAC__stream_encoder_set_loose_mid_side_stereo(FLAC__StreamEncoder *encoder, FLAC__bool value);
911 
912 /** Sets the apodization function(s) the encoder will use when windowing
913  *  audio data for LPC analysis.
914  *
915  * The \a specification is a plain ASCII string which specifies exactly
916  * which functions to use.  There may be more than one (up to 32),
917  * separated by \c ';' characters.  Some functions take one or more
918  * comma-separated arguments in parentheses.
919  *
920  * The available functions are \c bartlett, \c bartlett_hann,
921  * \c blackman, \c blackman_harris_4term_92db, \c connes, \c flattop,
922  * \c gauss(STDDEV), \c hamming, \c hann, \c kaiser_bessel, \c nuttall,
923  * \c rectangle, \c triangle, \c tukey(P), \c partial_tukey(n[/ov[/P]]),
924  * \c punchout_tukey(n[/ov[/P]]), \c welch.
925  *
926  * For \c gauss(STDDEV), STDDEV specifies the standard deviation
927  * (0<STDDEV<=0.5).
928  *
929  * For \c tukey(P), P specifies the fraction of the window that is
930  * tapered (0<=P<=1).  P=0 corresponds to \c rectangle and P=1
931  * corresponds to \c hann.
932  *
933  * Specifying \c partial_tukey or \c punchout_tukey works a little
934  * different. These do not specify a single apodization function, but
935  * a series of them with some overlap. partial_tukey specifies a series
936  * of small windows (all treated separately) while punchout_tukey
937  * specifies a series of windows that have a hole in them. In this way,
938  * the predictor is constructed with only a part of the block, which
939  * helps in case a block consists of dissimilar parts.
940  *
941  * The three parameters that can be specified for the functions are
942  * n, ov and P. n is the number of functions to add, ov is the overlap
943  * of the windows in case of partial_tukey and the overlap in the gaps
944  * in case of punchout_tukey. P is the fraction of the window that is
945  * tapered, like with a regular tukey window. The function can be
946  * specified with only a number, a number and an overlap, or a number
947  * an overlap and a P, for example, partial_tukey(3), partial_tukey(3/0.3)
948  * and partial_tukey(3/0.3/0.5) are all valid. ov should be smaller than 1
949  * and can be negative.
950  *
951  * Example specifications are \c "blackman" or
952  * \c "hann;triangle;tukey(0.5);tukey(0.25);tukey(0.125)"
953  *
954  * Any function that is specified erroneously is silently dropped.  Up
955  * to 32 functions are kept, the rest are dropped.  If the specification
956  * is empty the encoder defaults to \c "tukey(0.5)".
957  *
958  * When more than one function is specified, then for every subframe the
959  * encoder will try each of them separately and choose the window that
960  * results in the smallest compressed subframe.
961  *
962  * Note that each function specified causes the encoder to occupy a
963  * floating point array in which to store the window. Also note that the
964  * values of P, STDDEV and ov are locale-specific, so if the comma
965  * separator specified by the locale is a comma, a comma should be used.
966  *
967  * \default \c "tukey(0.5)"
968  * \param  encoder        An encoder instance to set.
969  * \param  specification  See above.
970  * \assert
971  *    \code encoder != NULL \endcode
972  *    \code specification != NULL \endcode
973  * \retval FLAC__bool
974  *    \c false if the encoder is already initialized, else \c true.
975  */
976 FLAC_API FLAC__bool FLAC__stream_encoder_set_apodization(FLAC__StreamEncoder *encoder, const char *specification);
977 
978 /** Set the maximum LPC order, or \c 0 to use only the fixed predictors.
979  *
980  * \default \c 8
981  * \param  encoder  An encoder instance to set.
982  * \param  value    See above.
983  * \assert
984  *    \code encoder != NULL \endcode
985  * \retval FLAC__bool
986  *    \c false if the encoder is already initialized, else \c true.
987  */
988 FLAC_API FLAC__bool FLAC__stream_encoder_set_max_lpc_order(FLAC__StreamEncoder *encoder, uint32_t value);
989 
990 /** Set the precision, in bits, of the quantized linear predictor
991  *  coefficients, or \c 0 to let the encoder select it based on the
992  *  blocksize.
993  *
994  * \note
995  * In the current implementation, qlp_coeff_precision + bits_per_sample must
996  * be less than 32.
997  *
998  * \default \c 0
999  * \param  encoder  An encoder instance to set.
1000  * \param  value    See above.
1001  * \assert
1002  *    \code encoder != NULL \endcode
1003  * \retval FLAC__bool
1004  *    \c false if the encoder is already initialized, else \c true.
1005  */
1006 FLAC_API FLAC__bool FLAC__stream_encoder_set_qlp_coeff_precision(FLAC__StreamEncoder *encoder, uint32_t value);
1007 
1008 /** Set to \c false to use only the specified quantized linear predictor
1009  *  coefficient precision, or \c true to search neighboring precision
1010  *  values and use the best one.
1011  *
1012  * \default \c false
1013  * \param  encoder  An encoder instance to set.
1014  * \param  value    See above.
1015  * \assert
1016  *    \code encoder != NULL \endcode
1017  * \retval FLAC__bool
1018  *    \c false if the encoder is already initialized, else \c true.
1019  */
1020 FLAC_API FLAC__bool FLAC__stream_encoder_set_do_qlp_coeff_prec_search(FLAC__StreamEncoder *encoder, FLAC__bool value);
1021 
1022 /** Deprecated.  Setting this value has no effect.
1023  *
1024  * \default \c false
1025  * \param  encoder  An encoder instance to set.
1026  * \param  value    See above.
1027  * \assert
1028  *    \code encoder != NULL \endcode
1029  * \retval FLAC__bool
1030  *    \c false if the encoder is already initialized, else \c true.
1031  */
1032 FLAC_API FLAC__bool FLAC__stream_encoder_set_do_escape_coding(FLAC__StreamEncoder *encoder, FLAC__bool value);
1033 
1034 /** Set to \c false to let the encoder estimate the best model order
1035  *  based on the residual signal energy, or \c true to force the
1036  *  encoder to evaluate all order models and select the best.
1037  *
1038  * \default \c false
1039  * \param  encoder  An encoder instance to set.
1040  * \param  value    See above.
1041  * \assert
1042  *    \code encoder != NULL \endcode
1043  * \retval FLAC__bool
1044  *    \c false if the encoder is already initialized, else \c true.
1045  */
1046 FLAC_API FLAC__bool FLAC__stream_encoder_set_do_exhaustive_model_search(FLAC__StreamEncoder *encoder, FLAC__bool value);
1047 
1048 /** Set the minimum partition order to search when coding the residual.
1049  *  This is used in tandem with
1050  *  FLAC__stream_encoder_set_max_residual_partition_order().
1051  *
1052  *  The partition order determines the context size in the residual.
1053  *  The context size will be approximately <tt>blocksize / (2 ^ order)</tt>.
1054  *
1055  *  Set both min and max values to \c 0 to force a single context,
1056  *  whose Rice parameter is based on the residual signal variance.
1057  *  Otherwise, set a min and max order, and the encoder will search
1058  *  all orders, using the mean of each context for its Rice parameter,
1059  *  and use the best.
1060  *
1061  * \default \c 0
1062  * \param  encoder  An encoder instance to set.
1063  * \param  value    See above.
1064  * \assert
1065  *    \code encoder != NULL \endcode
1066  * \retval FLAC__bool
1067  *    \c false if the encoder is already initialized, else \c true.
1068  */
1069 FLAC_API FLAC__bool FLAC__stream_encoder_set_min_residual_partition_order(FLAC__StreamEncoder *encoder, uint32_t value);
1070 
1071 /** Set the maximum partition order to search when coding the residual.
1072  *  This is used in tandem with
1073  *  FLAC__stream_encoder_set_min_residual_partition_order().
1074  *
1075  *  The partition order determines the context size in the residual.
1076  *  The context size will be approximately <tt>blocksize / (2 ^ order)</tt>.
1077  *
1078  *  Set both min and max values to \c 0 to force a single context,
1079  *  whose Rice parameter is based on the residual signal variance.
1080  *  Otherwise, set a min and max order, and the encoder will search
1081  *  all orders, using the mean of each context for its Rice parameter,
1082  *  and use the best.
1083  *
1084  * \default \c 5
1085  * \param  encoder  An encoder instance to set.
1086  * \param  value    See above.
1087  * \assert
1088  *    \code encoder != NULL \endcode
1089  * \retval FLAC__bool
1090  *    \c false if the encoder is already initialized, else \c true.
1091  */
1092 FLAC_API FLAC__bool FLAC__stream_encoder_set_max_residual_partition_order(FLAC__StreamEncoder *encoder, uint32_t value);
1093 
1094 /** Deprecated.  Setting this value has no effect.
1095  *
1096  * \default \c 0
1097  * \param  encoder  An encoder instance to set.
1098  * \param  value    See above.
1099  * \assert
1100  *    \code encoder != NULL \endcode
1101  * \retval FLAC__bool
1102  *    \c false if the encoder is already initialized, else \c true.
1103  */
1104 FLAC_API FLAC__bool FLAC__stream_encoder_set_rice_parameter_search_dist(FLAC__StreamEncoder *encoder, uint32_t value);
1105 
1106 /** Set an estimate of the total samples that will be encoded.
1107  *  This is merely an estimate and may be set to \c 0 if unknown.
1108  *  This value will be written to the STREAMINFO block before encoding,
1109  *  and can remove the need for the caller to rewrite the value later
1110  *  if the value is known before encoding.
1111  *
1112  * \default \c 0
1113  * \param  encoder  An encoder instance to set.
1114  * \param  value    See above.
1115  * \assert
1116  *    \code encoder != NULL \endcode
1117  * \retval FLAC__bool
1118  *    \c false if the encoder is already initialized, else \c true.
1119  */
1120 FLAC_API FLAC__bool FLAC__stream_encoder_set_total_samples_estimate(FLAC__StreamEncoder *encoder, FLAC__uint64 value);
1121 
1122 /** Set the metadata blocks to be emitted to the stream before encoding.
1123  *  A value of \c NULL, \c 0 implies no metadata; otherwise, supply an
1124  *  array of pointers to metadata blocks.  The array is non-const since
1125  *  the encoder may need to change the \a is_last flag inside them, and
1126  *  in some cases update seek point offsets.  Otherwise, the encoder will
1127  *  not modify or free the blocks.  It is up to the caller to free the
1128  *  metadata blocks after encoding finishes.
1129  *
1130  * \note
1131  * The encoder stores only copies of the pointers in the \a metadata array;
1132  * the metadata blocks themselves must survive at least until after
1133  * FLAC__stream_encoder_finish() returns.  Do not free the blocks until then.
1134  *
1135  * \note
1136  * The STREAMINFO block is always written and no STREAMINFO block may
1137  * occur in the supplied array.
1138  *
1139  * \note
1140  * By default the encoder does not create a SEEKTABLE.  If one is supplied
1141  * in the \a metadata array, but the client has specified that it does not
1142  * support seeking, then the SEEKTABLE will be written verbatim.  However
1143  * by itself this is not very useful as the client will not know the stream
1144  * offsets for the seekpoints ahead of time.  In order to get a proper
1145  * seektable the client must support seeking.  See next note.
1146  *
1147  * \note
1148  * SEEKTABLE blocks are handled specially.  Since you will not know
1149  * the values for the seek point stream offsets, you should pass in
1150  * a SEEKTABLE 'template', that is, a SEEKTABLE object with the
1151  * required sample numbers (or placeholder points), with \c 0 for the
1152  * \a frame_samples and \a stream_offset fields for each point.  If the
1153  * client has specified that it supports seeking by providing a seek
1154  * callback to FLAC__stream_encoder_init_stream() or both seek AND read
1155  * callback to FLAC__stream_encoder_init_ogg_stream() (or by using
1156  * FLAC__stream_encoder_init*_file() or FLAC__stream_encoder_init*_FILE()),
1157  * then while it is encoding the encoder will fill the stream offsets in
1158  * for you and when encoding is finished, it will seek back and write the
1159  * real values into the SEEKTABLE block in the stream.  There are helper
1160  * routines for manipulating seektable template blocks; see metadata.h:
1161  * FLAC__metadata_object_seektable_template_*().  If the client does
1162  * not support seeking, the SEEKTABLE will have inaccurate offsets which
1163  * will slow down or remove the ability to seek in the FLAC stream.
1164  *
1165  * \note
1166  * The encoder instance \b will modify the first \c SEEKTABLE block
1167  * as it transforms the template to a valid seektable while encoding,
1168  * but it is still up to the caller to free all metadata blocks after
1169  * encoding.
1170  *
1171  * \note
1172  * A VORBIS_COMMENT block may be supplied.  The vendor string in it
1173  * will be ignored.  libFLAC will use it's own vendor string. libFLAC
1174  * will not modify the passed-in VORBIS_COMMENT's vendor string, it
1175  * will simply write it's own into the stream.  If no VORBIS_COMMENT
1176  * block is present in the \a metadata array, libFLAC will write an
1177  * empty one, containing only the vendor string.
1178  *
1179  * \note The Ogg FLAC mapping requires that the VORBIS_COMMENT block be
1180  * the second metadata block of the stream.  The encoder already supplies
1181  * the STREAMINFO block automatically.  If \a metadata does not contain a
1182  * VORBIS_COMMENT block, the encoder will supply that too.  Otherwise, if
1183  * \a metadata does contain a VORBIS_COMMENT block and it is not the
1184  * first, the init function will reorder \a metadata by moving the
1185  * VORBIS_COMMENT block to the front; the relative ordering of the other
1186  * blocks will remain as they were.
1187  *
1188  * \note The Ogg FLAC mapping limits the number of metadata blocks per
1189  * stream to \c 65535.  If \a num_blocks exceeds this the function will
1190  * return \c false.
1191  *
1192  * \default \c NULL, 0
1193  * \param  encoder     An encoder instance to set.
1194  * \param  metadata    See above.
1195  * \param  num_blocks  See above.
1196  * \assert
1197  *    \code encoder != NULL \endcode
1198  * \retval FLAC__bool
1199  *    \c false if the encoder is already initialized, else \c true.
1200  *    \c false if the encoder is already initialized, or if
1201  *    \a num_blocks > 65535 if encoding to Ogg FLAC, else \c true.
1202  */
1203 FLAC_API FLAC__bool FLAC__stream_encoder_set_metadata(FLAC__StreamEncoder *encoder, FLAC__StreamMetadata **metadata, uint32_t num_blocks);
1204 
1205 /** Get the current encoder state.
1206  *
1207  * \param  encoder  An encoder instance to query.
1208  * \assert
1209  *    \code encoder != NULL \endcode
1210  * \retval FLAC__StreamEncoderState
1211  *    The current encoder state.
1212  */
1213 FLAC_API FLAC__StreamEncoderState FLAC__stream_encoder_get_state(const FLAC__StreamEncoder *encoder);
1214 
1215 /** Get the state of the verify stream decoder.
1216  *  Useful when the stream encoder state is
1217  *  \c FLAC__STREAM_ENCODER_VERIFY_DECODER_ERROR.
1218  *
1219  * \param  encoder  An encoder instance to query.
1220  * \assert
1221  *    \code encoder != NULL \endcode
1222  * \retval FLAC__StreamDecoderState
1223  *    The verify stream decoder state.
1224  */
1225 FLAC_API FLAC__StreamDecoderState FLAC__stream_encoder_get_verify_decoder_state(const FLAC__StreamEncoder *encoder);
1226 
1227 /** Get the current encoder state as a C string.
1228  *  This version automatically resolves
1229  *  \c FLAC__STREAM_ENCODER_VERIFY_DECODER_ERROR by getting the
1230  *  verify decoder's state.
1231  *
1232  * \param  encoder  A encoder instance to query.
1233  * \assert
1234  *    \code encoder != NULL \endcode
1235  * \retval const char *
1236  *    The encoder state as a C string.  Do not modify the contents.
1237  */
1238 FLAC_API const char *FLAC__stream_encoder_get_resolved_state_string(const FLAC__StreamEncoder *encoder);
1239 
1240 /** Get relevant values about the nature of a verify decoder error.
1241  *  Useful when the stream encoder state is
1242  *  \c FLAC__STREAM_ENCODER_VERIFY_DECODER_ERROR.  The arguments should
1243  *  be addresses in which the stats will be returned, or NULL if value
1244  *  is not desired.
1245  *
1246  * \param  encoder  An encoder instance to query.
1247  * \param  absolute_sample  The absolute sample number of the mismatch.
1248  * \param  frame_number  The number of the frame in which the mismatch occurred.
1249  * \param  channel       The channel in which the mismatch occurred.
1250  * \param  sample        The number of the sample (relative to the frame) in
1251  *                       which the mismatch occurred.
1252  * \param  expected      The expected value for the sample in question.
1253  * \param  got           The actual value returned by the decoder.
1254  * \assert
1255  *    \code encoder != NULL \endcode
1256  */
1257 FLAC_API void FLAC__stream_encoder_get_verify_decoder_error_stats(const FLAC__StreamEncoder *encoder, FLAC__uint64 *absolute_sample, uint32_t *frame_number, uint32_t *channel, uint32_t *sample, FLAC__int32 *expected, FLAC__int32 *got);
1258 
1259 /** Get the "verify" flag.
1260  *
1261  * \param  encoder  An encoder instance to query.
1262  * \assert
1263  *    \code encoder != NULL \endcode
1264  * \retval FLAC__bool
1265  *    See FLAC__stream_encoder_set_verify().
1266  */
1267 FLAC_API FLAC__bool FLAC__stream_encoder_get_verify(const FLAC__StreamEncoder *encoder);
1268 
1269 /** Get the <A HREF="../format.html#subset>Subset</A> flag.
1270  *
1271  * \param  encoder  An encoder instance to query.
1272  * \assert
1273  *    \code encoder != NULL \endcode
1274  * \retval FLAC__bool
1275  *    See FLAC__stream_encoder_set_streamable_subset().
1276  */
1277 FLAC_API FLAC__bool FLAC__stream_encoder_get_streamable_subset(const FLAC__StreamEncoder *encoder);
1278 
1279 /** Get the number of input channels being processed.
1280  *
1281  * \param  encoder  An encoder instance to query.
1282  * \assert
1283  *    \code encoder != NULL \endcode
1284  * \retval uint32_t
1285  *    See FLAC__stream_encoder_set_channels().
1286  */
1287 FLAC_API uint32_t FLAC__stream_encoder_get_channels(const FLAC__StreamEncoder *encoder);
1288 
1289 /** Get the input sample resolution setting.
1290  *
1291  * \param  encoder  An encoder instance to query.
1292  * \assert
1293  *    \code encoder != NULL \endcode
1294  * \retval uint32_t
1295  *    See FLAC__stream_encoder_set_bits_per_sample().
1296  */
1297 FLAC_API uint32_t FLAC__stream_encoder_get_bits_per_sample(const FLAC__StreamEncoder *encoder);
1298 
1299 /** Get the input sample rate setting.
1300  *
1301  * \param  encoder  An encoder instance to query.
1302  * \assert
1303  *    \code encoder != NULL \endcode
1304  * \retval uint32_t
1305  *    See FLAC__stream_encoder_set_sample_rate().
1306  */
1307 FLAC_API uint32_t FLAC__stream_encoder_get_sample_rate(const FLAC__StreamEncoder *encoder);
1308 
1309 /** Get the blocksize setting.
1310  *
1311  * \param  encoder  An encoder instance to query.
1312  * \assert
1313  *    \code encoder != NULL \endcode
1314  * \retval uint32_t
1315  *    See FLAC__stream_encoder_set_blocksize().
1316  */
1317 FLAC_API uint32_t FLAC__stream_encoder_get_blocksize(const FLAC__StreamEncoder *encoder);
1318 
1319 /** Get the "mid/side stereo coding" flag.
1320  *
1321  * \param  encoder  An encoder instance to query.
1322  * \assert
1323  *    \code encoder != NULL \endcode
1324  * \retval FLAC__bool
1325  *    See FLAC__stream_encoder_get_do_mid_side_stereo().
1326  */
1327 FLAC_API FLAC__bool FLAC__stream_encoder_get_do_mid_side_stereo(const FLAC__StreamEncoder *encoder);
1328 
1329 /** Get the "adaptive mid/side switching" flag.
1330  *
1331  * \param  encoder  An encoder instance to query.
1332  * \assert
1333  *    \code encoder != NULL \endcode
1334  * \retval FLAC__bool
1335  *    See FLAC__stream_encoder_set_loose_mid_side_stereo().
1336  */
1337 FLAC_API FLAC__bool FLAC__stream_encoder_get_loose_mid_side_stereo(const FLAC__StreamEncoder *encoder);
1338 
1339 /** Get the maximum LPC order setting.
1340  *
1341  * \param  encoder  An encoder instance to query.
1342  * \assert
1343  *    \code encoder != NULL \endcode
1344  * \retval uint32_t
1345  *    See FLAC__stream_encoder_set_max_lpc_order().
1346  */
1347 FLAC_API uint32_t FLAC__stream_encoder_get_max_lpc_order(const FLAC__StreamEncoder *encoder);
1348 
1349 /** Get the quantized linear predictor coefficient precision setting.
1350  *
1351  * \param  encoder  An encoder instance to query.
1352  * \assert
1353  *    \code encoder != NULL \endcode
1354  * \retval uint32_t
1355  *    See FLAC__stream_encoder_set_qlp_coeff_precision().
1356  */
1357 FLAC_API uint32_t FLAC__stream_encoder_get_qlp_coeff_precision(const FLAC__StreamEncoder *encoder);
1358 
1359 /** Get the qlp coefficient precision search flag.
1360  *
1361  * \param  encoder  An encoder instance to query.
1362  * \assert
1363  *    \code encoder != NULL \endcode
1364  * \retval FLAC__bool
1365  *    See FLAC__stream_encoder_set_do_qlp_coeff_prec_search().
1366  */
1367 FLAC_API FLAC__bool FLAC__stream_encoder_get_do_qlp_coeff_prec_search(const FLAC__StreamEncoder *encoder);
1368 
1369 /** Get the "escape coding" flag.
1370  *
1371  * \param  encoder  An encoder instance to query.
1372  * \assert
1373  *    \code encoder != NULL \endcode
1374  * \retval FLAC__bool
1375  *    See FLAC__stream_encoder_set_do_escape_coding().
1376  */
1377 FLAC_API FLAC__bool FLAC__stream_encoder_get_do_escape_coding(const FLAC__StreamEncoder *encoder);
1378 
1379 /** Get the exhaustive model search flag.
1380  *
1381  * \param  encoder  An encoder instance to query.
1382  * \assert
1383  *    \code encoder != NULL \endcode
1384  * \retval FLAC__bool
1385  *    See FLAC__stream_encoder_set_do_exhaustive_model_search().
1386  */
1387 FLAC_API FLAC__bool FLAC__stream_encoder_get_do_exhaustive_model_search(const FLAC__StreamEncoder *encoder);
1388 
1389 /** Get the minimum residual partition order setting.
1390  *
1391  * \param  encoder  An encoder instance to query.
1392  * \assert
1393  *    \code encoder != NULL \endcode
1394  * \retval uint32_t
1395  *    See FLAC__stream_encoder_set_min_residual_partition_order().
1396  */
1397 FLAC_API uint32_t FLAC__stream_encoder_get_min_residual_partition_order(const FLAC__StreamEncoder *encoder);
1398 
1399 /** Get maximum residual partition order setting.
1400  *
1401  * \param  encoder  An encoder instance to query.
1402  * \assert
1403  *    \code encoder != NULL \endcode
1404  * \retval uint32_t
1405  *    See FLAC__stream_encoder_set_max_residual_partition_order().
1406  */
1407 FLAC_API uint32_t FLAC__stream_encoder_get_max_residual_partition_order(const FLAC__StreamEncoder *encoder);
1408 
1409 /** Get the Rice parameter search distance setting.
1410  *
1411  * \param  encoder  An encoder instance to query.
1412  * \assert
1413  *    \code encoder != NULL \endcode
1414  * \retval uint32_t
1415  *    See FLAC__stream_encoder_set_rice_parameter_search_dist().
1416  */
1417 FLAC_API uint32_t FLAC__stream_encoder_get_rice_parameter_search_dist(const FLAC__StreamEncoder *encoder);
1418 
1419 /** Get the previously set estimate of the total samples to be encoded.
1420  *  The encoder merely mimics back the value given to
1421  *  FLAC__stream_encoder_set_total_samples_estimate() since it has no
1422  *  other way of knowing how many samples the client will encode.
1423  *
1424  * \param  encoder  An encoder instance to set.
1425  * \assert
1426  *    \code encoder != NULL \endcode
1427  * \retval FLAC__uint64
1428  *    See FLAC__stream_encoder_get_total_samples_estimate().
1429  */
1430 FLAC_API FLAC__uint64 FLAC__stream_encoder_get_total_samples_estimate(const FLAC__StreamEncoder *encoder);
1431 
1432 /** Initialize the encoder instance to encode native FLAC streams.
1433  *
1434  *  This flavor of initialization sets up the encoder to encode to a
1435  *  native FLAC stream. I/O is performed via callbacks to the client.
1436  *  For encoding to a plain file via filename or open \c FILE*,
1437  *  FLAC__stream_encoder_init_file() and FLAC__stream_encoder_init_FILE()
1438  *  provide a simpler interface.
1439  *
1440  *  This function should be called after FLAC__stream_encoder_new() and
1441  *  FLAC__stream_encoder_set_*() but before FLAC__stream_encoder_process()
1442  *  or FLAC__stream_encoder_process_interleaved().
1443  *  initialization succeeded.
1444  *
1445  *  The call to FLAC__stream_encoder_init_stream() currently will also
1446  *  immediately call the write callback several times, once with the \c fLaC
1447  *  signature, and once for each encoded metadata block.
1448  *
1449  * \param  encoder            An uninitialized encoder instance.
1450  * \param  write_callback     See FLAC__StreamEncoderWriteCallback.  This
1451  *                            pointer must not be \c NULL.
1452  * \param  seek_callback      See FLAC__StreamEncoderSeekCallback.  This
1453  *                            pointer may be \c NULL if seeking is not
1454  *                            supported.  The encoder uses seeking to go back
1455  *                            and write some some stream statistics to the
1456  *                            STREAMINFO block; this is recommended but not
1457  *                            necessary to create a valid FLAC stream.  If
1458  *                            \a seek_callback is not \c NULL then a
1459  *                            \a tell_callback must also be supplied.
1460  *                            Alternatively, a dummy seek callback that just
1461  *                            returns \c FLAC__STREAM_ENCODER_SEEK_STATUS_UNSUPPORTED
1462  *                            may also be supplied, all though this is slightly
1463  *                            less efficient for the encoder.
1464  * \param  tell_callback      See FLAC__StreamEncoderTellCallback.  This
1465  *                            pointer may be \c NULL if seeking is not
1466  *                            supported.  If \a seek_callback is \c NULL then
1467  *                            this argument will be ignored.  If
1468  *                            \a seek_callback is not \c NULL then a
1469  *                            \a tell_callback must also be supplied.
1470  *                            Alternatively, a dummy tell callback that just
1471  *                            returns \c FLAC__STREAM_ENCODER_TELL_STATUS_UNSUPPORTED
1472  *                            may also be supplied, all though this is slightly
1473  *                            less efficient for the encoder.
1474  * \param  metadata_callback  See FLAC__StreamEncoderMetadataCallback.  This
1475  *                            pointer may be \c NULL if the callback is not
1476  *                            desired.  If the client provides a seek callback,
1477  *                            this function is not necessary as the encoder
1478  *                            will automatically seek back and update the
1479  *                            STREAMINFO block.  It may also be \c NULL if the
1480  *                            client does not support seeking, since it will
1481  *                            have no way of going back to update the
1482  *                            STREAMINFO.  However the client can still supply
1483  *                            a callback if it would like to know the details
1484  *                            from the STREAMINFO.
1485  * \param  client_data        This value will be supplied to callbacks in their
1486  *                            \a client_data argument.
1487  * \assert
1488  *    \code encoder != NULL \endcode
1489  * \retval FLAC__StreamEncoderInitStatus
1490  *    \c FLAC__STREAM_ENCODER_INIT_STATUS_OK if initialization was successful;
1491  *    see FLAC__StreamEncoderInitStatus for the meanings of other return values.
1492  */
1493 FLAC_API FLAC__StreamEncoderInitStatus FLAC__stream_encoder_init_stream(FLAC__StreamEncoder *encoder, FLAC__StreamEncoderWriteCallback write_callback, FLAC__StreamEncoderSeekCallback seek_callback, FLAC__StreamEncoderTellCallback tell_callback, FLAC__StreamEncoderMetadataCallback metadata_callback, void *client_data);
1494 
1495 /** Initialize the encoder instance to encode Ogg FLAC streams.
1496  *
1497  *  This flavor of initialization sets up the encoder to encode to a FLAC
1498  *  stream in an Ogg container.  I/O is performed via callbacks to the
1499  *  client.  For encoding to a plain file via filename or open \c FILE*,
1500  *  FLAC__stream_encoder_init_ogg_file() and FLAC__stream_encoder_init_ogg_FILE()
1501  *  provide a simpler interface.
1502  *
1503  *  This function should be called after FLAC__stream_encoder_new() and
1504  *  FLAC__stream_encoder_set_*() but before FLAC__stream_encoder_process()
1505  *  or FLAC__stream_encoder_process_interleaved().
1506  *  initialization succeeded.
1507  *
1508  *  The call to FLAC__stream_encoder_init_ogg_stream() currently will also
1509  *  immediately call the write callback several times to write the metadata
1510  *  packets.
1511  *
1512  * \param  encoder            An uninitialized encoder instance.
1513  * \param  read_callback      See FLAC__StreamEncoderReadCallback.  This
1514  *                            pointer must not be \c NULL if \a seek_callback
1515  *                            is non-NULL since they are both needed to be
1516  *                            able to write data back to the Ogg FLAC stream
1517  *                            in the post-encode phase.
1518  * \param  write_callback     See FLAC__StreamEncoderWriteCallback.  This
1519  *                            pointer must not be \c NULL.
1520  * \param  seek_callback      See FLAC__StreamEncoderSeekCallback.  This
1521  *                            pointer may be \c NULL if seeking is not
1522  *                            supported.  The encoder uses seeking to go back
1523  *                            and write some some stream statistics to the
1524  *                            STREAMINFO block; this is recommended but not
1525  *                            necessary to create a valid FLAC stream.  If
1526  *                            \a seek_callback is not \c NULL then a
1527  *                            \a tell_callback must also be supplied.
1528  *                            Alternatively, a dummy seek callback that just
1529  *                            returns \c FLAC__STREAM_ENCODER_SEEK_STATUS_UNSUPPORTED
1530  *                            may also be supplied, all though this is slightly
1531  *                            less efficient for the encoder.
1532  * \param  tell_callback      See FLAC__StreamEncoderTellCallback.  This
1533  *                            pointer may be \c NULL if seeking is not
1534  *                            supported.  If \a seek_callback is \c NULL then
1535  *                            this argument will be ignored.  If
1536  *                            \a seek_callback is not \c NULL then a
1537  *                            \a tell_callback must also be supplied.
1538  *                            Alternatively, a dummy tell callback that just
1539  *                            returns \c FLAC__STREAM_ENCODER_TELL_STATUS_UNSUPPORTED
1540  *                            may also be supplied, all though this is slightly
1541  *                            less efficient for the encoder.
1542  * \param  metadata_callback  See FLAC__StreamEncoderMetadataCallback.  This
1543  *                            pointer may be \c NULL if the callback is not
1544  *                            desired.  If the client provides a seek callback,
1545  *                            this function is not necessary as the encoder
1546  *                            will automatically seek back and update the
1547  *                            STREAMINFO block.  It may also be \c NULL if the
1548  *                            client does not support seeking, since it will
1549  *                            have no way of going back to update the
1550  *                            STREAMINFO.  However the client can still supply
1551  *                            a callback if it would like to know the details
1552  *                            from the STREAMINFO.
1553  * \param  client_data        This value will be supplied to callbacks in their
1554  *                            \a client_data argument.
1555  * \assert
1556  *    \code encoder != NULL \endcode
1557  * \retval FLAC__StreamEncoderInitStatus
1558  *    \c FLAC__STREAM_ENCODER_INIT_STATUS_OK if initialization was successful;
1559  *    see FLAC__StreamEncoderInitStatus for the meanings of other return values.
1560  */
1561 FLAC_API FLAC__StreamEncoderInitStatus FLAC__stream_encoder_init_ogg_stream(FLAC__StreamEncoder *encoder, FLAC__StreamEncoderReadCallback read_callback, FLAC__StreamEncoderWriteCallback write_callback, FLAC__StreamEncoderSeekCallback seek_callback, FLAC__StreamEncoderTellCallback tell_callback, FLAC__StreamEncoderMetadataCallback metadata_callback, void *client_data);
1562 
1563 /** Initialize the encoder instance to encode native FLAC files.
1564  *
1565  *  This flavor of initialization sets up the encoder to encode to a
1566  *  plain native FLAC file.  For non-stdio streams, you must use
1567  *  FLAC__stream_encoder_init_stream() and provide callbacks for the I/O.
1568  *
1569  *  This function should be called after FLAC__stream_encoder_new() and
1570  *  FLAC__stream_encoder_set_*() but before FLAC__stream_encoder_process()
1571  *  or FLAC__stream_encoder_process_interleaved().
1572  *  initialization succeeded.
1573  *
1574  * \param  encoder            An uninitialized encoder instance.
1575  * \param  file               An open file.  The file should have been opened
1576  *                            with mode \c "w+b" and rewound.  The file
1577  *                            becomes owned by the encoder and should not be
1578  *                            manipulated by the client while encoding.
1579  *                            Unless \a file is \c stdout, it will be closed
1580  *                            when FLAC__stream_encoder_finish() is called.
1581  *                            Note however that a proper SEEKTABLE cannot be
1582  *                            created when encoding to \c stdout since it is
1583  *                            not seekable.
1584  * \param  progress_callback  See FLAC__StreamEncoderProgressCallback.  This
1585  *                            pointer may be \c NULL if the callback is not
1586  *                            desired.
1587  * \param  client_data        This value will be supplied to callbacks in their
1588  *                            \a client_data argument.
1589  * \assert
1590  *    \code encoder != NULL \endcode
1591  *    \code file != NULL \endcode
1592  * \retval FLAC__StreamEncoderInitStatus
1593  *    \c FLAC__STREAM_ENCODER_INIT_STATUS_OK if initialization was successful;
1594  *    see FLAC__StreamEncoderInitStatus for the meanings of other return values.
1595  */
1596 FLAC_API FLAC__StreamEncoderInitStatus FLAC__stream_encoder_init_FILE(FLAC__StreamEncoder *encoder, FILE *file, FLAC__StreamEncoderProgressCallback progress_callback, void *client_data);
1597 
1598 /** Initialize the encoder instance to encode Ogg FLAC files.
1599  *
1600  *  This flavor of initialization sets up the encoder to encode to a
1601  *  plain Ogg FLAC file.  For non-stdio streams, you must use
1602  *  FLAC__stream_encoder_init_ogg_stream() and provide callbacks for the I/O.
1603  *
1604  *  This function should be called after FLAC__stream_encoder_new() and
1605  *  FLAC__stream_encoder_set_*() but before FLAC__stream_encoder_process()
1606  *  or FLAC__stream_encoder_process_interleaved().
1607  *  initialization succeeded.
1608  *
1609  * \param  encoder            An uninitialized encoder instance.
1610  * \param  file               An open file.  The file should have been opened
1611  *                            with mode \c "w+b" and rewound.  The file
1612  *                            becomes owned by the encoder and should not be
1613  *                            manipulated by the client while encoding.
1614  *                            Unless \a file is \c stdout, it will be closed
1615  *                            when FLAC__stream_encoder_finish() is called.
1616  *                            Note however that a proper SEEKTABLE cannot be
1617  *                            created when encoding to \c stdout since it is
1618  *                            not seekable.
1619  * \param  progress_callback  See FLAC__StreamEncoderProgressCallback.  This
1620  *                            pointer may be \c NULL if the callback is not
1621  *                            desired.
1622  * \param  client_data        This value will be supplied to callbacks in their
1623  *                            \a client_data argument.
1624  * \assert
1625  *    \code encoder != NULL \endcode
1626  *    \code file != NULL \endcode
1627  * \retval FLAC__StreamEncoderInitStatus
1628  *    \c FLAC__STREAM_ENCODER_INIT_STATUS_OK if initialization was successful;
1629  *    see FLAC__StreamEncoderInitStatus for the meanings of other return values.
1630  */
1631 FLAC_API FLAC__StreamEncoderInitStatus FLAC__stream_encoder_init_ogg_FILE(FLAC__StreamEncoder *encoder, FILE *file, FLAC__StreamEncoderProgressCallback progress_callback, void *client_data);
1632 
1633 /** Initialize the encoder instance to encode native FLAC files.
1634  *
1635  *  This flavor of initialization sets up the encoder to encode to a plain
1636  *  FLAC file.  If POSIX fopen() semantics are not sufficient (for example,
1637  *  with Unicode filenames on Windows), you must use
1638  *  FLAC__stream_encoder_init_FILE(), or FLAC__stream_encoder_init_stream()
1639  *  and provide callbacks for the I/O.
1640  *
1641  *  This function should be called after FLAC__stream_encoder_new() and
1642  *  FLAC__stream_encoder_set_*() but before FLAC__stream_encoder_process()
1643  *  or FLAC__stream_encoder_process_interleaved().
1644  *  initialization succeeded.
1645  *
1646  * \param  encoder            An uninitialized encoder instance.
1647  * \param  filename           The name of the file to encode to.  The file will
1648  *                            be opened with fopen().  Use \c NULL to encode to
1649  *                            \c stdout.  Note however that a proper SEEKTABLE
1650  *                            cannot be created when encoding to \c stdout since
1651  *                            it is not seekable.
1652  * \param  progress_callback  See FLAC__StreamEncoderProgressCallback.  This
1653  *                            pointer may be \c NULL if the callback is not
1654  *                            desired.
1655  * \param  client_data        This value will be supplied to callbacks in their
1656  *                            \a client_data argument.
1657  * \assert
1658  *    \code encoder != NULL \endcode
1659  * \retval FLAC__StreamEncoderInitStatus
1660  *    \c FLAC__STREAM_ENCODER_INIT_STATUS_OK if initialization was successful;
1661  *    see FLAC__StreamEncoderInitStatus for the meanings of other return values.
1662  */
1663 FLAC_API FLAC__StreamEncoderInitStatus FLAC__stream_encoder_init_file(FLAC__StreamEncoder *encoder, const char *filename, FLAC__StreamEncoderProgressCallback progress_callback, void *client_data);
1664 
1665 /** Initialize the encoder instance to encode Ogg FLAC files.
1666  *
1667  *  This flavor of initialization sets up the encoder to encode to a plain
1668  *  Ogg FLAC file.  If POSIX fopen() semantics are not sufficient (for example,
1669  *  with Unicode filenames on Windows), you must use
1670  *  FLAC__stream_encoder_init_ogg_FILE(), or FLAC__stream_encoder_init_ogg_stream()
1671  *  and provide callbacks for the I/O.
1672  *
1673  *  This function should be called after FLAC__stream_encoder_new() and
1674  *  FLAC__stream_encoder_set_*() but before FLAC__stream_encoder_process()
1675  *  or FLAC__stream_encoder_process_interleaved().
1676  *  initialization succeeded.
1677  *
1678  * \param  encoder            An uninitialized encoder instance.
1679  * \param  filename           The name of the file to encode to.  The file will
1680  *                            be opened with fopen().  Use \c NULL to encode to
1681  *                            \c stdout.  Note however that a proper SEEKTABLE
1682  *                            cannot be created when encoding to \c stdout since
1683  *                            it is not seekable.
1684  * \param  progress_callback  See FLAC__StreamEncoderProgressCallback.  This
1685  *                            pointer may be \c NULL if the callback is not
1686  *                            desired.
1687  * \param  client_data        This value will be supplied to callbacks in their
1688  *                            \a client_data argument.
1689  * \assert
1690  *    \code encoder != NULL \endcode
1691  * \retval FLAC__StreamEncoderInitStatus
1692  *    \c FLAC__STREAM_ENCODER_INIT_STATUS_OK if initialization was successful;
1693  *    see FLAC__StreamEncoderInitStatus for the meanings of other return values.
1694  */
1695 FLAC_API FLAC__StreamEncoderInitStatus FLAC__stream_encoder_init_ogg_file(FLAC__StreamEncoder *encoder, const char *filename, FLAC__StreamEncoderProgressCallback progress_callback, void *client_data);
1696 
1697 /** Finish the encoding process.
1698  *  Flushes the encoding buffer, releases resources, resets the encoder
1699  *  settings to their defaults, and returns the encoder state to
1700  *  FLAC__STREAM_ENCODER_UNINITIALIZED.  Note that this can generate
1701  *  one or more write callbacks before returning, and will generate
1702  *  a metadata callback.
1703  *
1704  *  Note that in the course of processing the last frame, errors can
1705  *  occur, so the caller should be sure to check the return value to
1706  *  ensure the file was encoded properly.
1707  *
1708  *  In the event of a prematurely-terminated encode, it is not strictly
1709  *  necessary to call this immediately before FLAC__stream_encoder_delete()
1710  *  but it is good practice to match every FLAC__stream_encoder_init_*()
1711  *  with a FLAC__stream_encoder_finish().
1712  *
1713  * \param  encoder  An uninitialized encoder instance.
1714  * \assert
1715  *    \code encoder != NULL \endcode
1716  * \retval FLAC__bool
1717  *    \c false if an error occurred processing the last frame; or if verify
1718  *    mode is set (see FLAC__stream_encoder_set_verify()), there was a
1719  *    verify mismatch; else \c true.  If \c false, caller should check the
1720  *    state with FLAC__stream_encoder_get_state() for more information
1721  *    about the error.
1722  */
1723 FLAC_API FLAC__bool FLAC__stream_encoder_finish(FLAC__StreamEncoder *encoder);
1724 
1725 /** Submit data for encoding.
1726  *  This version allows you to supply the input data via an array of
1727  *  pointers, each pointer pointing to an array of \a samples samples
1728  *  representing one channel.  The samples need not be block-aligned,
1729  *  but each channel should have the same number of samples.  Each sample
1730  *  should be a signed integer, right-justified to the resolution set by
1731  *  FLAC__stream_encoder_set_bits_per_sample().  For example, if the
1732  *  resolution is 16 bits per sample, the samples should all be in the
1733  *  range [-32768,32767].
1734  *
1735  *  For applications where channel order is important, channels must
1736  *  follow the order as described in the
1737  *  <A HREF="../format.html#frame_header">frame header</A>.
1738  *
1739  * \param  encoder  An initialized encoder instance in the OK state.
1740  * \param  buffer   An array of pointers to each channel's signal.
1741  * \param  samples  The number of samples in one channel.
1742  * \assert
1743  *    \code encoder != NULL \endcode
1744  *    \code FLAC__stream_encoder_get_state(encoder) == FLAC__STREAM_ENCODER_OK \endcode
1745  * \retval FLAC__bool
1746  *    \c true if successful, else \c false; in this case, check the
1747  *    encoder state with FLAC__stream_encoder_get_state() to see what
1748  *    went wrong.
1749  */
1750 FLAC_API FLAC__bool FLAC__stream_encoder_process(FLAC__StreamEncoder *encoder, const FLAC__int32 * const buffer[], uint32_t samples);
1751 
1752 /** Submit data for encoding.
1753  *  This version allows you to supply the input data where the channels
1754  *  are interleaved into a single array (i.e. channel0_sample0,
1755  *  channel1_sample0, ... , channelN_sample0, channel0_sample1, ...).
1756  *  The samples need not be block-aligned but they must be
1757  *  sample-aligned, i.e. the first value should be channel0_sample0
1758  *  and the last value channelN_sampleM.  Each sample should be a signed
1759  *  integer, right-justified to the resolution set by
1760  *  FLAC__stream_encoder_set_bits_per_sample().  For example, if the
1761  *  resolution is 16 bits per sample, the samples should all be in the
1762  *  range [-32768,32767].
1763  *
1764  *  For applications where channel order is important, channels must
1765  *  follow the order as described in the
1766  *  <A HREF="../format.html#frame_header">frame header</A>.
1767  *
1768  * \param  encoder  An initialized encoder instance in the OK state.
1769  * \param  buffer   An array of channel-interleaved data (see above).
1770  * \param  samples  The number of samples in one channel, the same as for
1771  *                  FLAC__stream_encoder_process().  For example, if
1772  *                  encoding two channels, \c 1000 \a samples corresponds
1773  *                  to a \a buffer of 2000 values.
1774  * \assert
1775  *    \code encoder != NULL \endcode
1776  *    \code FLAC__stream_encoder_get_state(encoder) == FLAC__STREAM_ENCODER_OK \endcode
1777  * \retval FLAC__bool
1778  *    \c true if successful, else \c false; in this case, check the
1779  *    encoder state with FLAC__stream_encoder_get_state() to see what
1780  *    went wrong.
1781  */
1782 FLAC_API FLAC__bool FLAC__stream_encoder_process_interleaved(FLAC__StreamEncoder *encoder, const FLAC__int32 buffer[], uint32_t samples);
1783 
1784 /* \} */
1785 
1786 #ifdef __cplusplus
1787 }
1788 #endif
1789 
1790 #endif
1791