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1 /*
2  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 #ifndef VPX_VPX_VPX_ENCODER_H_
11 #define VPX_VPX_VPX_ENCODER_H_
12 
13 /*!\defgroup encoder Encoder Algorithm Interface
14  * \ingroup codec
15  * This abstraction allows applications using this encoder to easily support
16  * multiple video formats with minimal code duplication. This section describes
17  * the interface common to all encoders.
18  * @{
19  */
20 
21 /*!\file
22  * \brief Describes the encoder algorithm interface to applications.
23  *
24  * This file describes the interface between an application and a
25  * video encoder algorithm.
26  *
27  */
28 #ifdef __cplusplus
29 extern "C" {
30 #endif
31 
32 #include "./vpx_codec.h"
33 #include "./vpx_ext_ratectrl.h"
34 #include "./vpx_tpl.h"
35 
36 /*! Temporal Scalability: Maximum length of the sequence defining frame
37  * layer membership
38  */
39 #define VPX_TS_MAX_PERIODICITY 16
40 
41 /*! Temporal Scalability: Maximum number of coding layers */
42 #define VPX_TS_MAX_LAYERS 5
43 
44 /*! Temporal+Spatial Scalability: Maximum number of coding layers */
45 #define VPX_MAX_LAYERS 12  // 3 temporal + 4 spatial layers are allowed.
46 
47 /*! Spatial Scalability: Maximum number of coding layers */
48 #define VPX_SS_MAX_LAYERS 5
49 
50 /*! Spatial Scalability: Default number of coding layers */
51 #define VPX_SS_DEFAULT_LAYERS 1
52 
53 /*!\brief Current ABI version number
54  *
55  * \internal
56  * If this file is altered in any way that changes the ABI, this value
57  * must be bumped.  Examples include, but are not limited to, changing
58  * types, removing or reassigning enums, adding/removing/rearranging
59  * fields to structures
60  */
61 #define VPX_ENCODER_ABI_VERSION                                \
62   (16 + VPX_CODEC_ABI_VERSION + VPX_EXT_RATECTRL_ABI_VERSION + \
63    VPX_TPL_ABI_VERSION) /**<\hideinitializer*/
64 
65 /*! \brief Encoder capabilities bitfield
66  *
67  *  Each encoder advertises the capabilities it supports as part of its
68  *  ::vpx_codec_iface_t interface structure. Capabilities are extra
69  *  interfaces or functionality, and are not required to be supported
70  *  by an encoder.
71  *
72  *  The available flags are specified by VPX_CODEC_CAP_* defines.
73  */
74 #define VPX_CODEC_CAP_PSNR 0x10000 /**< Can issue PSNR packets */
75 
76 /*! Can output one partition at a time. Each partition is returned in its
77  *  own VPX_CODEC_CX_FRAME_PKT, with the FRAME_IS_FRAGMENT flag set for
78  *  every partition but the last. In this mode all frames are always
79  *  returned partition by partition.
80  */
81 #define VPX_CODEC_CAP_OUTPUT_PARTITION 0x20000
82 
83 /*! \brief Initialization-time Feature Enabling
84  *
85  *  Certain codec features must be known at initialization time, to allow
86  *  for proper memory allocation.
87  *
88  *  The available flags are specified by VPX_CODEC_USE_* defines.
89  */
90 #define VPX_CODEC_USE_PSNR 0x10000 /**< Calculate PSNR on each frame */
91 /*!\brief Make the encoder output one  partition at a time. */
92 #define VPX_CODEC_USE_OUTPUT_PARTITION 0x20000
93 #define VPX_CODEC_USE_HIGHBITDEPTH 0x40000 /**< Use high bitdepth */
94 
95 /*!\brief Generic fixed size buffer structure
96  *
97  * This structure is able to hold a reference to any fixed size buffer.
98  */
99 typedef struct vpx_fixed_buf {
100   void *buf;       /**< Pointer to the data */
101   size_t sz;       /**< Length of the buffer, in chars */
102 } vpx_fixed_buf_t; /**< alias for struct vpx_fixed_buf */
103 
104 /*!\brief Time Stamp Type
105  *
106  * An integer, which when multiplied by the stream's time base, provides
107  * the absolute time of a sample.
108  */
109 typedef int64_t vpx_codec_pts_t;
110 
111 /*!\brief Compressed Frame Flags
112  *
113  * This type represents a bitfield containing information about a compressed
114  * frame that may be useful to an application. The most significant 16 bits
115  * can be used by an algorithm to provide additional detail, for example to
116  * support frame types that are codec specific (MPEG-1 D-frames for example)
117  */
118 typedef uint32_t vpx_codec_frame_flags_t;
119 #define VPX_FRAME_IS_KEY 0x1u /**< frame is the start of a GOP */
120 /*!\brief frame can be dropped without affecting the stream (no future frame
121  * depends on this one) */
122 #define VPX_FRAME_IS_DROPPABLE 0x2u
123 /*!\brief frame should be decoded but will not be shown */
124 #define VPX_FRAME_IS_INVISIBLE 0x4u
125 /*!\brief this is a fragment of the encoded frame */
126 #define VPX_FRAME_IS_FRAGMENT 0x8u
127 
128 /*!\brief Error Resilient flags
129  *
130  * These flags define which error resilient features to enable in the
131  * encoder. The flags are specified through the
132  * vpx_codec_enc_cfg::g_error_resilient variable.
133  */
134 typedef uint32_t vpx_codec_er_flags_t;
135 /*!\brief Improve resiliency against losses of whole frames */
136 #define VPX_ERROR_RESILIENT_DEFAULT 0x1u
137 /*!\brief The frame partitions are independently decodable by the bool decoder,
138  * meaning that partitions can be decoded even though earlier partitions have
139  * been lost. Note that intra prediction is still done over the partition
140  * boundary.
141  * \note This is only supported by VP8.*/
142 #define VPX_ERROR_RESILIENT_PARTITIONS 0x2u
143 
144 /*!\brief Encoder output packet variants
145  *
146  * This enumeration lists the different kinds of data packets that can be
147  * returned by calls to vpx_codec_get_cx_data(). Algorithms \ref MAY
148  * extend this list to provide additional functionality.
149  */
150 enum vpx_codec_cx_pkt_kind {
151   VPX_CODEC_CX_FRAME_PKT,    /**< Compressed video frame */
152   VPX_CODEC_STATS_PKT,       /**< Two-pass statistics for this frame */
153   VPX_CODEC_FPMB_STATS_PKT,  /**< first pass mb statistics for this frame */
154   VPX_CODEC_PSNR_PKT,        /**< PSNR statistics for this frame */
155   VPX_CODEC_CUSTOM_PKT = 256 /**< Algorithm extensions  */
156 };
157 
158 /*!\brief Encoder output packet
159  *
160  * This structure contains the different kinds of output data the encoder
161  * may produce while compressing a frame.
162  */
163 typedef struct vpx_codec_cx_pkt {
164   enum vpx_codec_cx_pkt_kind kind; /**< packet variant */
165   union {
166     struct {
167       void *buf; /**< compressed data buffer */
168       size_t sz; /**< length of compressed data */
169       /*!\brief time stamp to show frame (in timebase units) */
170       vpx_codec_pts_t pts;
171       /*!\brief duration to show frame (in timebase units) */
172       unsigned long duration;
173       vpx_codec_frame_flags_t flags; /**< flags for this frame */
174       /*!\brief the partition id defines the decoding order of the partitions.
175        * Only applicable when "output partition" mode is enabled. First
176        * partition has id 0.*/
177       int partition_id;
178       /*!\brief Width and height of frames in this packet. VP8 will only use the
179        * first one.*/
180       unsigned int width[VPX_SS_MAX_LAYERS];  /**< frame width */
181       unsigned int height[VPX_SS_MAX_LAYERS]; /**< frame height */
182       /*!\brief Flag to indicate if spatial layer frame in this packet is
183        * encoded or dropped. VP8 will always be set to 1.*/
184       uint8_t spatial_layer_encoded[VPX_SS_MAX_LAYERS];
185     } frame;                            /**< data for compressed frame packet */
186     vpx_fixed_buf_t twopass_stats;      /**< data for two-pass packet */
187     vpx_fixed_buf_t firstpass_mb_stats; /**< first pass mb packet */
188     struct vpx_psnr_pkt {
189       unsigned int samples[4]; /**< Number of samples, total/y/u/v */
190       uint64_t sse[4];         /**< sum squared error, total/y/u/v */
191       double psnr[4];          /**< PSNR, total/y/u/v */
192     } psnr;                    /**< data for PSNR packet */
193     vpx_fixed_buf_t raw;       /**< data for arbitrary packets */
194 
195     /* This packet size is fixed to allow codecs to extend this
196      * interface without having to manage storage for raw packets,
197      * i.e., if it's smaller than 128 bytes, you can store in the
198      * packet list directly.
199      */
200     char pad[128 - sizeof(enum vpx_codec_cx_pkt_kind)]; /**< fixed sz */
201   } data;                                               /**< packet data */
202 } vpx_codec_cx_pkt_t; /**< alias for struct vpx_codec_cx_pkt */
203 
204 /*!\brief Encoder return output buffer callback
205  *
206  * This callback function, when registered, returns with packets when each
207  * spatial layer is encoded.
208  */
209 typedef void (*vpx_codec_enc_output_cx_pkt_cb_fn_t)(vpx_codec_cx_pkt_t *pkt,
210                                                     void *user_data);
211 
212 /*!\brief Callback function pointer / user data pair storage */
213 typedef struct vpx_codec_enc_output_cx_cb_pair {
214   vpx_codec_enc_output_cx_pkt_cb_fn_t output_cx_pkt; /**< Callback function */
215   void *user_priv; /**< Pointer to private data */
216 } vpx_codec_priv_output_cx_pkt_cb_pair_t;
217 
218 /*!\brief Rational Number
219  *
220  * This structure holds a fractional value.
221  */
222 typedef struct vpx_rational {
223   int num;        /**< fraction numerator */
224   int den;        /**< fraction denominator */
225 } vpx_rational_t; /**< alias for struct vpx_rational */
226 
227 /*!\brief Multi-pass Encoding Pass */
228 typedef enum vpx_enc_pass {
229   VPX_RC_ONE_PASS,   /**< Single pass mode */
230   VPX_RC_FIRST_PASS, /**< First pass of multi-pass mode */
231   VPX_RC_LAST_PASS   /**< Final pass of multi-pass mode */
232 } vpx_enc_pass;
233 
234 /*!\brief Rate control mode */
235 enum vpx_rc_mode {
236   VPX_VBR, /**< Variable Bit Rate (VBR) mode */
237   VPX_CBR, /**< Constant Bit Rate (CBR) mode */
238   VPX_CQ,  /**< Constrained Quality (CQ)  mode */
239   VPX_Q,   /**< Constant Quality (Q) mode */
240 };
241 
242 /*!\brief Keyframe placement mode.
243  *
244  * This enumeration determines whether keyframes are placed automatically by
245  * the encoder or whether this behavior is disabled. Older releases of this
246  * SDK were implemented such that VPX_KF_FIXED meant keyframes were disabled.
247  * This name is confusing for this behavior, so the new symbols to be used
248  * are VPX_KF_AUTO and VPX_KF_DISABLED.
249  */
250 enum vpx_kf_mode {
251   VPX_KF_FIXED,       /**< deprecated, implies VPX_KF_DISABLED */
252   VPX_KF_AUTO,        /**< Encoder determines optimal placement automatically */
253   VPX_KF_DISABLED = 0 /**< Encoder does not place keyframes. */
254 };
255 
256 /*!\brief Encoded Frame Flags
257  *
258  * This type indicates a bitfield to be passed to vpx_codec_encode(), defining
259  * per-frame boolean values. By convention, bits common to all codecs will be
260  * named VPX_EFLAG_*, and bits specific to an algorithm will be named
261  * /algo/_eflag_*. The lower order 16 bits are reserved for common use.
262  */
263 typedef long vpx_enc_frame_flags_t;
264 #define VPX_EFLAG_FORCE_KF (1 << 0) /**< Force this frame to be a keyframe */
265 
266 /*!\brief Encoder configuration structure
267  *
268  * This structure contains the encoder settings that have common representations
269  * across all codecs. This doesn't imply that all codecs support all features,
270  * however.
271  */
272 typedef struct vpx_codec_enc_cfg {
273   /*
274    * generic settings (g)
275    */
276 
277   /*!\brief Deprecated: Algorithm specific "usage" value
278    *
279    * This value must be zero.
280    */
281   unsigned int g_usage;
282 
283   /*!\brief Maximum number of threads to use
284    *
285    * For multi-threaded implementations, use no more than this number of
286    * threads. The codec may use fewer threads than allowed. The value
287    * 0 is equivalent to the value 1.
288    */
289   unsigned int g_threads;
290 
291   /*!\brief Bitstream profile to use
292    *
293    * Some codecs support a notion of multiple bitstream profiles. Typically
294    * this maps to a set of features that are turned on or off. Often the
295    * profile to use is determined by the features of the intended decoder.
296    * Consult the documentation for the codec to determine the valid values
297    * for this parameter, or set to zero for a sane default.
298    */
299   unsigned int g_profile; /**< profile of bitstream to use */
300 
301   /*!\brief Width of the frame
302    *
303    * This value identifies the presentation resolution of the frame,
304    * in pixels. Note that the frames passed as input to the encoder must
305    * have this resolution. Frames will be presented by the decoder in this
306    * resolution, independent of any spatial resampling the encoder may do.
307    */
308   unsigned int g_w;
309 
310   /*!\brief Height of the frame
311    *
312    * This value identifies the presentation resolution of the frame,
313    * in pixels. Note that the frames passed as input to the encoder must
314    * have this resolution. Frames will be presented by the decoder in this
315    * resolution, independent of any spatial resampling the encoder may do.
316    */
317   unsigned int g_h;
318 
319   /*!\brief Bit-depth of the codec
320    *
321    * This value identifies the bit_depth of the codec,
322    * Only certain bit-depths are supported as identified in the
323    * vpx_bit_depth_t enum.
324    */
325   vpx_bit_depth_t g_bit_depth;
326 
327   /*!\brief Bit-depth of the input frames
328    *
329    * This value identifies the bit_depth of the input frames in bits.
330    * Note that the frames passed as input to the encoder must have
331    * this bit-depth.
332    */
333   unsigned int g_input_bit_depth;
334 
335   /*!\brief Stream timebase units
336    *
337    * Indicates the smallest interval of time, in seconds, used by the stream.
338    * For fixed frame rate material, or variable frame rate material where
339    * frames are timed at a multiple of a given clock (ex: video capture),
340    * the \ref RECOMMENDED method is to set the timebase to the reciprocal
341    * of the frame rate (ex: 1001/30000 for 29.970 Hz NTSC). This allows the
342    * pts to correspond to the frame number, which can be handy. For
343    * re-encoding video from containers with absolute time timestamps, the
344    * \ref RECOMMENDED method is to set the timebase to that of the parent
345    * container or multimedia framework (ex: 1/1000 for ms, as in FLV).
346    */
347   struct vpx_rational g_timebase;
348 
349   /*!\brief Enable error resilient modes.
350    *
351    * The error resilient bitfield indicates to the encoder which features
352    * it should enable to take measures for streaming over lossy or noisy
353    * links.
354    */
355   vpx_codec_er_flags_t g_error_resilient;
356 
357   /*!\brief Multi-pass Encoding Mode
358    *
359    * This value should be set to the current phase for multi-pass encoding.
360    * For single pass, set to #VPX_RC_ONE_PASS.
361    */
362   enum vpx_enc_pass g_pass;
363 
364   /*!\brief Allow lagged encoding
365    *
366    * If set, this value allows the encoder to consume a number of input
367    * frames before producing output frames. This allows the encoder to
368    * base decisions for the current frame on future frames. This does
369    * increase the latency of the encoding pipeline, so it is not appropriate
370    * in all situations (ex: realtime encoding).
371    *
372    * Note that this is a maximum value -- the encoder may produce frames
373    * sooner than the given limit. Set this value to 0 to disable this
374    * feature.
375    */
376   unsigned int g_lag_in_frames;
377 
378   /*
379    * rate control settings (rc)
380    */
381 
382   /*!\brief Temporal resampling configuration, if supported by the codec.
383    *
384    * Temporal resampling allows the codec to "drop" frames as a strategy to
385    * meet its target data rate. This can cause temporal discontinuities in
386    * the encoded video, which may appear as stuttering during playback. This
387    * trade-off is often acceptable, but for many applications is not. It can
388    * be disabled in these cases.
389    *
390    * This threshold is described as a percentage of the target data buffer.
391    * When the data buffer falls below this percentage of fullness, a
392    * dropped frame is indicated. Set the threshold to zero (0) to disable
393    * this feature.
394    */
395   unsigned int rc_dropframe_thresh;
396 
397   /*!\brief Enable/disable spatial resampling, if supported by the codec.
398    *
399    * Spatial resampling allows the codec to compress a lower resolution
400    * version of the frame, which is then upscaled by the encoder to the
401    * correct presentation resolution. This increases visual quality at
402    * low data rates, at the expense of CPU time on the encoder/decoder.
403    */
404   unsigned int rc_resize_allowed;
405 
406   /*!\brief Internal coded frame width.
407    *
408    * If spatial resampling is enabled this specifies the width of the
409    * encoded frame.
410    */
411   unsigned int rc_scaled_width;
412 
413   /*!\brief Internal coded frame height.
414    *
415    * If spatial resampling is enabled this specifies the height of the
416    * encoded frame.
417    */
418   unsigned int rc_scaled_height;
419 
420   /*!\brief Spatial resampling up watermark.
421    *
422    * This threshold is described as a percentage of the target data buffer.
423    * When the data buffer rises above this percentage of fullness, the
424    * encoder will step up to a higher resolution version of the frame.
425    */
426   unsigned int rc_resize_up_thresh;
427 
428   /*!\brief Spatial resampling down watermark.
429    *
430    * This threshold is described as a percentage of the target data buffer.
431    * When the data buffer falls below this percentage of fullness, the
432    * encoder will step down to a lower resolution version of the frame.
433    */
434   unsigned int rc_resize_down_thresh;
435 
436   /*!\brief Rate control algorithm to use.
437    *
438    * Indicates whether the end usage of this stream is to be streamed over
439    * a bandwidth constrained link, indicating that Constant Bit Rate (CBR)
440    * mode should be used, or whether it will be played back on a high
441    * bandwidth link, as from a local disk, where higher variations in
442    * bitrate are acceptable.
443    */
444   enum vpx_rc_mode rc_end_usage;
445 
446   /*!\brief Two-pass stats buffer.
447    *
448    * A buffer containing all of the stats packets produced in the first
449    * pass, concatenated.
450    */
451   vpx_fixed_buf_t rc_twopass_stats_in;
452 
453   /*!\brief first pass mb stats buffer.
454    *
455    * A buffer containing all of the first pass mb stats packets produced
456    * in the first pass, concatenated.
457    */
458   vpx_fixed_buf_t rc_firstpass_mb_stats_in;
459 
460   /*!\brief Target data rate
461    *
462    * Target bitrate to use for this stream, in kilobits per second.
463    */
464   unsigned int rc_target_bitrate;
465 
466   /*
467    * quantizer settings
468    */
469 
470   /*!\brief Minimum (Best Quality) Quantizer
471    *
472    * The quantizer is the most direct control over the quality of the
473    * encoded image. The range of valid values for the quantizer is codec
474    * specific. Consult the documentation for the codec to determine the
475    * values to use.
476    */
477   unsigned int rc_min_quantizer;
478 
479   /*!\brief Maximum (Worst Quality) Quantizer
480    *
481    * The quantizer is the most direct control over the quality of the
482    * encoded image. The range of valid values for the quantizer is codec
483    * specific. Consult the documentation for the codec to determine the
484    * values to use.
485    */
486   unsigned int rc_max_quantizer;
487 
488   /*
489    * bitrate tolerance
490    */
491 
492   /*!\brief Rate control adaptation undershoot control
493    *
494    * VP8: Expressed as a percentage of the target bitrate,
495    * controls the maximum allowed adaptation speed of the codec.
496    * This factor controls the maximum amount of bits that can
497    * be subtracted from the target bitrate in order to compensate
498    * for prior overshoot.
499    * VP9: Expressed as a percentage of the target bitrate, a threshold
500    * undershoot level (current rate vs target) beyond which more aggressive
501    * corrective measures are taken.
502    *   *
503    * Valid values in the range VP8:0-100 VP9: 0-100.
504    */
505   unsigned int rc_undershoot_pct;
506 
507   /*!\brief Rate control adaptation overshoot control
508    *
509    * VP8: Expressed as a percentage of the target bitrate,
510    * controls the maximum allowed adaptation speed of the codec.
511    * This factor controls the maximum amount of bits that can
512    * be added to the target bitrate in order to compensate for
513    * prior undershoot.
514    * VP9: Expressed as a percentage of the target bitrate, a threshold
515    * overshoot level (current rate vs target) beyond which more aggressive
516    * corrective measures are taken.
517    *
518    * Valid values in the range VP8:0-100 VP9: 0-100.
519    */
520   unsigned int rc_overshoot_pct;
521 
522   /*
523    * decoder buffer model parameters
524    */
525 
526   /*!\brief Decoder Buffer Size
527    *
528    * This value indicates the amount of data that may be buffered by the
529    * decoding application. Note that this value is expressed in units of
530    * time (milliseconds). For example, a value of 5000 indicates that the
531    * client will buffer (at least) 5000ms worth of encoded data. Use the
532    * target bitrate (#rc_target_bitrate) to convert to bits/bytes, if
533    * necessary.
534    */
535   unsigned int rc_buf_sz;
536 
537   /*!\brief Decoder Buffer Initial Size
538    *
539    * This value indicates the amount of data that will be buffered by the
540    * decoding application prior to beginning playback. This value is
541    * expressed in units of time (milliseconds). Use the target bitrate
542    * (#rc_target_bitrate) to convert to bits/bytes, if necessary.
543    */
544   unsigned int rc_buf_initial_sz;
545 
546   /*!\brief Decoder Buffer Optimal Size
547    *
548    * This value indicates the amount of data that the encoder should try
549    * to maintain in the decoder's buffer. This value is expressed in units
550    * of time (milliseconds). Use the target bitrate (#rc_target_bitrate)
551    * to convert to bits/bytes, if necessary.
552    */
553   unsigned int rc_buf_optimal_sz;
554 
555   /*
556    * 2 pass rate control parameters
557    */
558 
559   /*!\brief Two-pass mode CBR/VBR bias
560    *
561    * Bias, expressed on a scale of 0 to 100, for determining target size
562    * for the current frame. The value 0 indicates the optimal CBR mode
563    * value should be used. The value 100 indicates the optimal VBR mode
564    * value should be used. Values in between indicate which way the
565    * encoder should "lean."
566    */
567   unsigned int rc_2pass_vbr_bias_pct;
568 
569   /*!\brief Two-pass mode per-GOP minimum bitrate
570    *
571    * This value, expressed as a percentage of the target bitrate, indicates
572    * the minimum bitrate to be used for a single GOP (aka "section")
573    */
574   unsigned int rc_2pass_vbr_minsection_pct;
575 
576   /*!\brief Two-pass mode per-GOP maximum bitrate
577    *
578    * This value, expressed as a percentage of the target bitrate, indicates
579    * the maximum bitrate to be used for a single GOP (aka "section")
580    */
581   unsigned int rc_2pass_vbr_maxsection_pct;
582 
583   /*!\brief Two-pass corpus vbr mode complexity control
584    * Used only in VP9: A value representing the corpus midpoint complexity
585    * for corpus vbr mode. This value defaults to 0 which disables corpus vbr
586    * mode in favour of normal vbr mode.
587    */
588   unsigned int rc_2pass_vbr_corpus_complexity;
589 
590   /*
591    * keyframing settings (kf)
592    */
593 
594   /*!\brief Keyframe placement mode
595    *
596    * This value indicates whether the encoder should place keyframes at a
597    * fixed interval, or determine the optimal placement automatically
598    * (as governed by the #kf_min_dist and #kf_max_dist parameters)
599    */
600   enum vpx_kf_mode kf_mode;
601 
602   /*!\brief Keyframe minimum interval
603    *
604    * This value, expressed as a number of frames, prevents the encoder from
605    * placing a keyframe nearer than kf_min_dist to the previous keyframe. At
606    * least kf_min_dist frames non-keyframes will be coded before the next
607    * keyframe. Set kf_min_dist equal to kf_max_dist for a fixed interval.
608    */
609   unsigned int kf_min_dist;
610 
611   /*!\brief Keyframe maximum interval
612    *
613    * This value, expressed as a number of frames, forces the encoder to code
614    * a keyframe if one has not been coded in the last kf_max_dist frames.
615    * A value of 0 implies all frames will be keyframes. Set kf_min_dist
616    * equal to kf_max_dist for a fixed interval.
617    */
618   unsigned int kf_max_dist;
619 
620   /*
621    * Spatial scalability settings (ss)
622    */
623 
624   /*!\brief Number of spatial coding layers.
625    *
626    * This value specifies the number of spatial coding layers to be used.
627    */
628   unsigned int ss_number_layers;
629 
630   /*!\brief Enable auto alt reference flags for each spatial layer.
631    *
632    * These values specify if auto alt reference frame is enabled for each
633    * spatial layer.
634    */
635   int ss_enable_auto_alt_ref[VPX_SS_MAX_LAYERS];
636 
637   /*!\brief Target bitrate for each spatial layer.
638    *
639    * These values specify the target coding bitrate to be used for each
640    * spatial layer. (in kbps)
641    */
642   unsigned int ss_target_bitrate[VPX_SS_MAX_LAYERS];
643 
644   /*!\brief Number of temporal coding layers.
645    *
646    * This value specifies the number of temporal layers to be used.
647    */
648   unsigned int ts_number_layers;
649 
650   /*!\brief Target bitrate for each temporal layer.
651    *
652    * These values specify the target coding bitrate to be used for each
653    * temporal layer. (in kbps)
654    */
655   unsigned int ts_target_bitrate[VPX_TS_MAX_LAYERS];
656 
657   /*!\brief Frame rate decimation factor for each temporal layer.
658    *
659    * These values specify the frame rate decimation factors to apply
660    * to each temporal layer.
661    */
662   unsigned int ts_rate_decimator[VPX_TS_MAX_LAYERS];
663 
664   /*!\brief Length of the sequence defining frame temporal layer membership.
665    *
666    * This value specifies the length of the sequence that defines the
667    * membership of frames to temporal layers. For example, if the
668    * ts_periodicity = 8, then the frames are assigned to coding layers with a
669    * repeated sequence of length 8.
670    */
671   unsigned int ts_periodicity;
672 
673   /*!\brief Template defining the membership of frames to temporal layers.
674    *
675    * This array defines the membership of frames to temporal coding layers.
676    * For a 2-layer encoding that assigns even numbered frames to one temporal
677    * layer (0) and odd numbered frames to a second temporal layer (1) with
678    * ts_periodicity=8, then ts_layer_id = (0,1,0,1,0,1,0,1).
679    */
680   unsigned int ts_layer_id[VPX_TS_MAX_PERIODICITY];
681 
682   /*!\brief Target bitrate for each spatial/temporal layer.
683    *
684    * These values specify the target coding bitrate to be used for each
685    * spatial/temporal layer. (in kbps)
686    *
687    */
688   unsigned int layer_target_bitrate[VPX_MAX_LAYERS];
689 
690   /*!\brief Temporal layering mode indicating which temporal layering scheme to
691    * use.
692    *
693    * The value (refer to VP9E_TEMPORAL_LAYERING_MODE) specifies the
694    * temporal layering mode to use.
695    *
696    */
697   int temporal_layering_mode;
698 
699   /*!\brief A flag indicating whether to use external rate control parameters.
700    * By default is 0. If set to 1, the following parameters will be used in the
701    * rate control system.
702    */
703   int use_vizier_rc_params;
704 
705   /*!\brief Active worst quality factor.
706    *
707    * Rate control parameters, set from external experiment results.
708    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
709    * used. Otherwise, the default value is used.
710    *
711    */
712   vpx_rational_t active_wq_factor;
713 
714   /*!\brief Error per macroblock adjustment factor.
715    *
716    * Rate control parameters, set from external experiment results.
717    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
718    * used. Otherwise, the default value is used.
719    *
720    */
721   vpx_rational_t err_per_mb_factor;
722 
723   /*!\brief Second reference default decay limit.
724    *
725    * Rate control parameters, set from external experiment results.
726    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
727    * used. Otherwise, the default value is used.
728    *
729    */
730   vpx_rational_t sr_default_decay_limit;
731 
732   /*!\brief Second reference difference factor.
733    *
734    * Rate control parameters, set from external experiment results.
735    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
736    * used. Otherwise, the default value is used.
737    *
738    */
739   vpx_rational_t sr_diff_factor;
740 
741   /*!\brief Keyframe error per macroblock adjustment factor.
742    *
743    * Rate control parameters, set from external experiment results.
744    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
745    * used. Otherwise, the default value is used.
746    *
747    */
748   vpx_rational_t kf_err_per_mb_factor;
749 
750   /*!\brief Keyframe minimum boost adjustment factor.
751    *
752    * Rate control parameters, set from external experiment results.
753    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
754    * used. Otherwise, the default value is used.
755    *
756    */
757   vpx_rational_t kf_frame_min_boost_factor;
758 
759   /*!\brief Keyframe maximum boost adjustment factor, for the first keyframe
760    * in a chunk.
761    *
762    * Rate control parameters, set from external experiment results.
763    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
764    * used. Otherwise, the default value is used.
765    *
766    */
767   vpx_rational_t kf_frame_max_boost_first_factor;
768 
769   /*!\brief Keyframe maximum boost adjustment factor, for subsequent keyframes.
770    *
771    * Rate control parameters, set from external experiment results.
772    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
773    * used. Otherwise, the default value is used.
774    *
775    */
776   vpx_rational_t kf_frame_max_boost_subs_factor;
777 
778   /*!\brief Keyframe maximum total boost adjustment factor.
779    *
780    * Rate control parameters, set from external experiment results.
781    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
782    * used. Otherwise, the default value is used.
783    *
784    */
785   vpx_rational_t kf_max_total_boost_factor;
786 
787   /*!\brief Golden frame maximum total boost adjustment factor.
788    *
789    * Rate control parameters, set from external experiment results.
790    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
791    * used. Otherwise, the default value is used.
792    *
793    */
794   vpx_rational_t gf_max_total_boost_factor;
795 
796   /*!\brief Golden frame maximum boost adjustment factor.
797    *
798    * Rate control parameters, set from external experiment results.
799    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
800    * used. Otherwise, the default value is used.
801    *
802    */
803   vpx_rational_t gf_frame_max_boost_factor;
804 
805   /*!\brief Zero motion power factor.
806    *
807    * Rate control parameters, set from external experiment results.
808    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
809    * used. Otherwise, the default value is used.
810    *
811    */
812   vpx_rational_t zm_factor;
813 
814   /*!\brief Rate-distortion multiplier for inter frames.
815    * The multiplier is a crucial parameter in the calculation of rate distortion
816    * cost. It is often related to the qp (qindex) value.
817    * Rate control parameters, could be set from external experiment results.
818    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
819    * used. Otherwise, the default value is used.
820    *
821    */
822   vpx_rational_t rd_mult_inter_qp_fac;
823 
824   /*!\brief Rate-distortion multiplier for alt-ref frames.
825    * The multiplier is a crucial parameter in the calculation of rate distortion
826    * cost. It is often related to the qp (qindex) value.
827    * Rate control parameters, could be set from external experiment results.
828    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
829    * used. Otherwise, the default value is used.
830    *
831    */
832   vpx_rational_t rd_mult_arf_qp_fac;
833 
834   /*!\brief Rate-distortion multiplier for key frames.
835    * The multiplier is a crucial parameter in the calculation of rate distortion
836    * cost. It is often related to the qp (qindex) value.
837    * Rate control parameters, could be set from external experiment results.
838    * Only when |use_vizier_rc_params| is set to 1, the pass in value will be
839    * used. Otherwise, the default value is used.
840    *
841    */
842   vpx_rational_t rd_mult_key_qp_fac;
843 } vpx_codec_enc_cfg_t; /**< alias for struct vpx_codec_enc_cfg */
844 
845 /*!\brief  vp9 svc extra configure parameters
846  *
847  * This defines max/min quantizers and scale factors for each layer
848  *
849  */
850 typedef struct vpx_svc_parameters {
851   int max_quantizers[VPX_MAX_LAYERS];     /**< Max Q for each layer */
852   int min_quantizers[VPX_MAX_LAYERS];     /**< Min Q for each layer */
853   int scaling_factor_num[VPX_MAX_LAYERS]; /**< Scaling factor-numerator */
854   int scaling_factor_den[VPX_MAX_LAYERS]; /**< Scaling factor-denominator */
855   int speed_per_layer[VPX_MAX_LAYERS];    /**< Speed setting for each sl */
856   int temporal_layering_mode;             /**< Temporal layering mode */
857   int loopfilter_ctrl[VPX_MAX_LAYERS];    /**< Loopfilter ctrl for each sl */
858 } vpx_svc_extra_cfg_t;
859 
860 /*!\brief Initialize an encoder instance
861  *
862  * Initializes an encoder context using the given interface. Applications
863  * should call the vpx_codec_enc_init convenience macro instead of this
864  * function directly, to ensure that the ABI version number parameter
865  * is properly initialized.
866  *
867  * If the library was configured with --disable-multithread, this call
868  * is not thread safe and should be guarded with a lock if being used
869  * in a multithreaded context.
870  *
871  * If vpx_codec_enc_init_ver() fails, it is not necessary to call
872  * vpx_codec_destroy() on the encoder context.
873  *
874  * \param[in]    ctx     Pointer to this instance's context.
875  * \param[in]    iface   Pointer to the algorithm interface to use.
876  * \param[in]    cfg     Configuration to use, if known. May be NULL.
877  * \param[in]    flags   Bitfield of VPX_CODEC_USE_* flags
878  * \param[in]    ver     ABI version number. Must be set to
879  *                       VPX_ENCODER_ABI_VERSION
880  * \retval #VPX_CODEC_OK
881  *     The decoder algorithm initialized.
882  * \retval #VPX_CODEC_MEM_ERROR
883  *     Memory allocation failed.
884  */
885 vpx_codec_err_t vpx_codec_enc_init_ver(vpx_codec_ctx_t *ctx,
886                                        vpx_codec_iface_t *iface,
887                                        const vpx_codec_enc_cfg_t *cfg,
888                                        vpx_codec_flags_t flags, int ver);
889 
890 /*!\brief Convenience macro for vpx_codec_enc_init_ver()
891  *
892  * Ensures the ABI version parameter is properly set.
893  */
894 #define vpx_codec_enc_init(ctx, iface, cfg, flags) \
895   vpx_codec_enc_init_ver(ctx, iface, cfg, flags, VPX_ENCODER_ABI_VERSION)
896 
897 /*!\brief Initialize multi-encoder instance
898  *
899  * Initializes multi-encoder context using the given interface.
900  * Applications should call the vpx_codec_enc_init_multi convenience macro
901  * instead of this function directly, to ensure that the ABI version number
902  * parameter is properly initialized.
903  *
904  * \param[in]    ctx     Pointer to this instance's context.
905  * \param[in]    iface   Pointer to the algorithm interface to use.
906  * \param[in]    cfg     Configuration to use, if known. May be NULL.
907  * \param[in]    num_enc Total number of encoders.
908  * \param[in]    flags   Bitfield of VPX_CODEC_USE_* flags
909  * \param[in]    dsf     Pointer to down-sampling factors.
910  * \param[in]    ver     ABI version number. Must be set to
911  *                       VPX_ENCODER_ABI_VERSION
912  * \retval #VPX_CODEC_OK
913  *     The encoder algorithm has been initialized.
914  * \retval #VPX_CODEC_MEM_ERROR
915  *     Memory allocation failed.
916  */
917 vpx_codec_err_t vpx_codec_enc_init_multi_ver(
918     vpx_codec_ctx_t *ctx, vpx_codec_iface_t *iface, vpx_codec_enc_cfg_t *cfg,
919     int num_enc, vpx_codec_flags_t flags, vpx_rational_t *dsf, int ver);
920 
921 /*!\brief Convenience macro for vpx_codec_enc_init_multi_ver()
922  *
923  * Ensures the ABI version parameter is properly set.
924  */
925 #define vpx_codec_enc_init_multi(ctx, iface, cfg, num_enc, flags, dsf) \
926   vpx_codec_enc_init_multi_ver(ctx, iface, cfg, num_enc, flags, dsf,   \
927                                VPX_ENCODER_ABI_VERSION)
928 
929 /*!\brief Get a default configuration
930  *
931  * Initializes a encoder configuration structure with default values. Supports
932  * the notion of "usages" so that an algorithm may offer different default
933  * settings depending on the user's intended goal. This function \ref SHOULD
934  * be called by all applications to initialize the configuration structure
935  * before specializing the configuration with application specific values.
936  *
937  * \param[in]    iface     Pointer to the algorithm interface to use.
938  * \param[out]   cfg       Configuration buffer to populate.
939  * \param[in]    usage     Must be set to 0.
940  *
941  * \retval #VPX_CODEC_OK
942  *     The configuration was populated.
943  * \retval #VPX_CODEC_INCAPABLE
944  *     Interface is not an encoder interface.
945  * \retval #VPX_CODEC_INVALID_PARAM
946  *     A parameter was NULL, or the usage value was not recognized.
947  */
948 vpx_codec_err_t vpx_codec_enc_config_default(vpx_codec_iface_t *iface,
949                                              vpx_codec_enc_cfg_t *cfg,
950                                              unsigned int usage);
951 
952 /*!\brief Set or change configuration
953  *
954  * Reconfigures an encoder instance according to the given configuration.
955  *
956  * \param[in]    ctx     Pointer to this instance's context
957  * \param[in]    cfg     Configuration buffer to use
958  *
959  * \retval #VPX_CODEC_OK
960  *     The configuration was populated.
961  * \retval #VPX_CODEC_INCAPABLE
962  *     Interface is not an encoder interface.
963  * \retval #VPX_CODEC_INVALID_PARAM
964  *     A parameter was NULL, or the usage value was not recognized.
965  */
966 vpx_codec_err_t vpx_codec_enc_config_set(vpx_codec_ctx_t *ctx,
967                                          const vpx_codec_enc_cfg_t *cfg);
968 
969 /*!\brief Get global stream headers
970  *
971  * Retrieves a stream level global header packet, if supported by the codec.
972  *
973  * \li VP8: Unsupported
974  * \li VP9: Returns a buffer of <tt>ID (1 byte)|Length (1 byte)|Length
975  * bytes</tt> values. The function should be called after encoding to retrieve
976  * the most accurate information.
977  *
978  * \param[in]    ctx     Pointer to this instance's context
979  *
980  * \retval NULL
981  *     Encoder does not support global header
982  * \retval Non-NULL
983  *     Pointer to buffer containing global header packet. The buffer pointer
984  *     and its contents are only valid for the lifetime of \a ctx. The contents
985  *     may change in subsequent calls to the function.
986  * \sa
987  * https://www.webmproject.org/docs/container/#vp9-codec-feature-metadata-codecprivate
988  */
989 vpx_fixed_buf_t *vpx_codec_get_global_headers(vpx_codec_ctx_t *ctx);
990 
991 /*!\brief deadline parameter analogous to VPx REALTIME mode. */
992 #define VPX_DL_REALTIME (1)
993 /*!\brief deadline parameter analogous to  VPx GOOD QUALITY mode. */
994 #define VPX_DL_GOOD_QUALITY (1000000)
995 /*!\brief deadline parameter analogous to VPx BEST QUALITY mode. */
996 #define VPX_DL_BEST_QUALITY (0)
997 /*!\brief Encode a frame
998  *
999  * Encodes a video frame at the given "presentation time." The presentation
1000  * time stamp (PTS) \ref MUST be strictly increasing.
1001  *
1002  * The encoder supports the notion of a soft real-time deadline. Given a
1003  * non-zero value to the deadline parameter, the encoder will make a "best
1004  * effort" guarantee to  return before the given time slice expires. It is
1005  * implicit that limiting the available time to encode will degrade the
1006  * output quality. The encoder can be given an unlimited time to produce the
1007  * best possible frame by specifying a deadline of '0'. This deadline
1008  * supersedes the VPx notion of "best quality, good quality, realtime".
1009  * Applications that wish to map these former settings to the new deadline
1010  * based system can use the symbols #VPX_DL_REALTIME, #VPX_DL_GOOD_QUALITY,
1011  * and #VPX_DL_BEST_QUALITY.
1012  *
1013  * When the last frame has been passed to the encoder, this function should
1014  * continue to be called, with the img parameter set to NULL. This will
1015  * signal the end-of-stream condition to the encoder and allow it to encode
1016  * any held buffers. Encoding is complete when vpx_codec_encode() is called
1017  * and vpx_codec_get_cx_data() returns no data.
1018  *
1019  * \param[in]    ctx       Pointer to this instance's context
1020  * \param[in]    img       Image data to encode, NULL to flush.
1021  * \param[in]    pts       Presentation time stamp, in timebase units.
1022  * \param[in]    duration  Duration to show frame, in timebase units.
1023  * \param[in]    flags     Flags to use for encoding this frame.
1024  * \param[in]    deadline  Time to spend encoding, in microseconds. (0=infinite)
1025  *
1026  * \retval #VPX_CODEC_OK
1027  *     The configuration was populated.
1028  * \retval #VPX_CODEC_INCAPABLE
1029  *     Interface is not an encoder interface.
1030  * \retval #VPX_CODEC_INVALID_PARAM
1031  *     A parameter was NULL, the image format is unsupported, etc.
1032  */
1033 vpx_codec_err_t vpx_codec_encode(vpx_codec_ctx_t *ctx, const vpx_image_t *img,
1034                                  vpx_codec_pts_t pts, unsigned long duration,
1035                                  vpx_enc_frame_flags_t flags,
1036                                  unsigned long deadline);
1037 
1038 /*!\brief Set compressed data output buffer
1039  *
1040  * Sets the buffer that the codec should output the compressed data
1041  * into. This call effectively sets the buffer pointer returned in the
1042  * next VPX_CODEC_CX_FRAME_PKT packet. Subsequent packets will be
1043  * appended into this buffer. The buffer is preserved across frames,
1044  * so applications must periodically call this function after flushing
1045  * the accumulated compressed data to disk or to the network to reset
1046  * the pointer to the buffer's head.
1047  *
1048  * `pad_before` bytes will be skipped before writing the compressed
1049  * data, and `pad_after` bytes will be appended to the packet. The size
1050  * of the packet will be the sum of the size of the actual compressed
1051  * data, pad_before, and pad_after. The padding bytes will be preserved
1052  * (not overwritten).
1053  *
1054  * Note that calling this function does not guarantee that the returned
1055  * compressed data will be placed into the specified buffer. In the
1056  * event that the encoded data will not fit into the buffer provided,
1057  * the returned packet \ref MAY point to an internal buffer, as it would
1058  * if this call were never used. In this event, the output packet will
1059  * NOT have any padding, and the application must free space and copy it
1060  * to the proper place. This is of particular note in configurations
1061  * that may output multiple packets for a single encoded frame (e.g., lagged
1062  * encoding) or if the application does not reset the buffer periodically.
1063  *
1064  * Applications may restore the default behavior of the codec providing
1065  * the compressed data buffer by calling this function with a NULL
1066  * buffer.
1067  *
1068  * Applications \ref MUSTNOT call this function during iteration of
1069  * vpx_codec_get_cx_data().
1070  *
1071  * \param[in]    ctx         Pointer to this instance's context
1072  * \param[in]    buf         Buffer to store compressed data into
1073  * \param[in]    pad_before  Bytes to skip before writing compressed data
1074  * \param[in]    pad_after   Bytes to skip after writing compressed data
1075  *
1076  * \retval #VPX_CODEC_OK
1077  *     The buffer was set successfully.
1078  * \retval #VPX_CODEC_INVALID_PARAM
1079  *     A parameter was NULL, the image format is unsupported, etc.
1080  */
1081 vpx_codec_err_t vpx_codec_set_cx_data_buf(vpx_codec_ctx_t *ctx,
1082                                           const vpx_fixed_buf_t *buf,
1083                                           unsigned int pad_before,
1084                                           unsigned int pad_after);
1085 
1086 /*!\brief Encoded data iterator
1087  *
1088  * Iterates over a list of data packets to be passed from the encoder to the
1089  * application. The different kinds of packets available are enumerated in
1090  * #vpx_codec_cx_pkt_kind.
1091  *
1092  * #VPX_CODEC_CX_FRAME_PKT packets should be passed to the application's
1093  * muxer. Multiple compressed frames may be in the list.
1094  * #VPX_CODEC_STATS_PKT packets should be appended to a global buffer.
1095  *
1096  * The application \ref MUST silently ignore any packet kinds that it does
1097  * not recognize or support.
1098  *
1099  * The data buffers returned from this function are only guaranteed to be
1100  * valid until the application makes another call to any vpx_codec_* function.
1101  *
1102  * \param[in]     ctx      Pointer to this instance's context
1103  * \param[in,out] iter     Iterator storage, initialized to NULL
1104  *
1105  * \return Returns a pointer to an output data packet (compressed frame data,
1106  *         two-pass statistics, etc.) or NULL to signal end-of-list.
1107  *
1108  */
1109 const vpx_codec_cx_pkt_t *vpx_codec_get_cx_data(vpx_codec_ctx_t *ctx,
1110                                                 vpx_codec_iter_t *iter);
1111 
1112 /*!\brief Get Preview Frame
1113  *
1114  * Returns an image that can be used as a preview. Shows the image as it would
1115  * exist at the decompressor. The application \ref MUST NOT write into this
1116  * image buffer.
1117  *
1118  * \param[in]     ctx      Pointer to this instance's context
1119  *
1120  * \return Returns a pointer to a preview image, or NULL if no image is
1121  *         available.
1122  *
1123  */
1124 const vpx_image_t *vpx_codec_get_preview_frame(vpx_codec_ctx_t *ctx);
1125 
1126 /*!@} - end defgroup encoder*/
1127 #ifdef __cplusplus
1128 }
1129 #endif
1130 #endif  // VPX_VPX_VPX_ENCODER_H_
1131