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1 /*
2  * jpeglib.h
3  *
4  * Copyright (C) 1991-1998, Thomas G. Lane.
5  * This file is part of the Independent JPEG Group's software.
6  * For conditions of distribution and use, see the accompanying README file.
7  *
8  * This file defines the application interface for the JPEG library.
9  * Most applications using the library need only include this file,
10  * and perhaps jerror.h if they want to know the exact error codes.
11  */
12 
13 #ifndef JPEGLIB_H
14 #define JPEGLIB_H
15 
16 /*
17  * First we include the configuration files that record how this
18  * installation of the JPEG library is set up.  jconfig.h can be
19  * generated automatically for many systems.  jmorecfg.h contains
20  * manual configuration options that most people need not worry about.
21  */
22 
23 #ifndef JCONFIG_INCLUDED	/* in case jinclude.h already did */
24 #include "jconfig.h"		/* widely used configuration options */
25 #endif
26 #include "jmorecfg.h"		/* seldom changed options */
27 
28 
29 /* Version ID for the JPEG library.
30  * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60".
31  */
32 
33 #define JPEG_LIB_VERSION  62	/* Version 6b */
34 
35 
36 /* Various constants determining the sizes of things.
37  * All of these are specified by the JPEG standard, so don't change them
38  * if you want to be compatible.
39  */
40 
41 #define DCTSIZE		    8	/* The basic DCT block is 8x8 samples */
42 #define DCTSIZE2	    64	/* DCTSIZE squared; # of elements in a block */
43 #define NUM_QUANT_TBLS      4	/* Quantization tables are numbered 0..3 */
44 #define NUM_HUFF_TBLS       4	/* Huffman tables are numbered 0..3 */
45 #define NUM_ARITH_TBLS      16	/* Arith-coding tables are numbered 0..15 */
46 #define MAX_COMPS_IN_SCAN   4	/* JPEG limit on # of components in one scan */
47 #define MAX_SAMP_FACTOR     4	/* JPEG limit on sampling factors */
48 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
49  * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
50  * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
51  * to handle it.  We even let you do this from the jconfig.h file.  However,
52  * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
53  * sometimes emits noncompliant files doesn't mean you should too.
54  */
55 #define C_MAX_BLOCKS_IN_MCU   10 /* compressor's limit on blocks per MCU */
56 #ifndef D_MAX_BLOCKS_IN_MCU
57 #define D_MAX_BLOCKS_IN_MCU   10 /* decompressor's limit on blocks per MCU */
58 #endif
59 
60 
61 /* Data structures for images (arrays of samples and of DCT coefficients).
62  * On 80x86 machines, the image arrays are too big for near pointers,
63  * but the pointer arrays can fit in near memory.
64  */
65 
66 typedef JSAMPLE FAR *JSAMPROW;	/* ptr to one image row of pixel samples. */
67 typedef JSAMPROW *JSAMPARRAY;	/* ptr to some rows (a 2-D sample array) */
68 typedef JSAMPARRAY *JSAMPIMAGE;	/* a 3-D sample array: top index is color */
69 
70 typedef JCOEF JBLOCK[DCTSIZE2];	/* one block of coefficients */
71 typedef JBLOCK FAR *JBLOCKROW;	/* pointer to one row of coefficient blocks */
72 typedef JBLOCKROW *JBLOCKARRAY;		/* a 2-D array of coefficient blocks */
73 typedef JBLOCKARRAY *JBLOCKIMAGE;	/* a 3-D array of coefficient blocks */
74 
75 typedef JCOEF FAR *JCOEFPTR;	/* useful in a couple of places */
76 
77 
78 /* Types for JPEG compression parameters and working tables. */
79 
80 
81 /* DCT coefficient quantization tables. */
82 
83 typedef struct {
84   /* This array gives the coefficient quantizers in natural array order
85    * (not the zigzag order in which they are stored in a JPEG DQT marker).
86    * CAUTION: IJG versions prior to v6a kept this array in zigzag order.
87    */
88   UINT16 quantval[DCTSIZE2];	/* quantization step for each coefficient */
89   /* This field is used only during compression.  It's initialized FALSE when
90    * the table is created, and set TRUE when it's been output to the file.
91    * You could suppress output of a table by setting this to TRUE.
92    * (See jpeg_suppress_tables for an example.)
93    */
94   boolean sent_table;		/* TRUE when table has been output */
95 } JQUANT_TBL;
96 
97 
98 /* Huffman coding tables. */
99 
100 typedef struct {
101   /* These two fields directly represent the contents of a JPEG DHT marker */
102   UINT8 bits[17];		/* bits[k] = # of symbols with codes of */
103 				/* length k bits; bits[0] is unused */
104   UINT8 huffval[256];		/* The symbols, in order of incr code length */
105   /* This field is used only during compression.  It's initialized FALSE when
106    * the table is created, and set TRUE when it's been output to the file.
107    * You could suppress output of a table by setting this to TRUE.
108    * (See jpeg_suppress_tables for an example.)
109    */
110   boolean sent_table;		/* TRUE when table has been output */
111 } JHUFF_TBL;
112 
113 
114 /* Basic info about one component (color channel). */
115 
116 typedef struct {
117   /* These values are fixed over the whole image. */
118   /* For compression, they must be supplied by parameter setup; */
119   /* for decompression, they are read from the SOF marker. */
120   int component_id;		/* identifier for this component (0..255) */
121   int component_index;		/* its index in SOF or cinfo->comp_info[] */
122   int h_samp_factor;		/* horizontal sampling factor (1..4) */
123   int v_samp_factor;		/* vertical sampling factor (1..4) */
124   int quant_tbl_no;		/* quantization table selector (0..3) */
125   /* These values may vary between scans. */
126   /* For compression, they must be supplied by parameter setup; */
127   /* for decompression, they are read from the SOS marker. */
128   /* The decompressor output side may not use these variables. */
129   int dc_tbl_no;		/* DC entropy table selector (0..3) */
130   int ac_tbl_no;		/* AC entropy table selector (0..3) */
131 
132   /* Remaining fields should be treated as private by applications. */
133 
134   /* These values are computed during compression or decompression startup: */
135   /* Component's size in DCT blocks.
136    * Any dummy blocks added to complete an MCU are not counted; therefore
137    * these values do not depend on whether a scan is interleaved or not.
138    */
139   JDIMENSION width_in_blocks;
140   JDIMENSION height_in_blocks;
141   /* Size of a DCT block in samples.  Always DCTSIZE for compression.
142    * For decompression this is the size of the output from one DCT block,
143    * reflecting any scaling we choose to apply during the IDCT step.
144    * Values of 1,2,4,8 are likely to be supported.  Note that different
145    * components may receive different IDCT scalings.
146    */
147   int DCT_scaled_size;
148   /* The downsampled dimensions are the component's actual, unpadded number
149    * of samples at the main buffer (preprocessing/compression interface), thus
150    * downsampled_width = ceil(image_width * Hi/Hmax)
151    * and similarly for height.  For decompression, IDCT scaling is included, so
152    * downsampled_width = ceil(image_width * Hi/Hmax * DCT_scaled_size/DCTSIZE)
153    */
154   JDIMENSION downsampled_width;	 /* actual width in samples */
155   JDIMENSION downsampled_height; /* actual height in samples */
156   /* This flag is used only for decompression.  In cases where some of the
157    * components will be ignored (eg grayscale output from YCbCr image),
158    * we can skip most computations for the unused components.
159    */
160   boolean component_needed;	/* do we need the value of this component? */
161 
162   /* These values are computed before starting a scan of the component. */
163   /* The decompressor output side may not use these variables. */
164   int MCU_width;		/* number of blocks per MCU, horizontally */
165   int MCU_height;		/* number of blocks per MCU, vertically */
166   int MCU_blocks;		/* MCU_width * MCU_height */
167   int MCU_sample_width;		/* MCU width in samples, MCU_width*DCT_scaled_size */
168   int last_col_width;		/* # of non-dummy blocks across in last MCU */
169   int last_row_height;		/* # of non-dummy blocks down in last MCU */
170 
171   /* Saved quantization table for component; NULL if none yet saved.
172    * See jdinput.c comments about the need for this information.
173    * This field is currently used only for decompression.
174    */
175   JQUANT_TBL * quant_table;
176 
177   /* Private per-component storage for DCT or IDCT subsystem. */
178   void * dct_table;
179 } jpeg_component_info;
180 
181 
182 /* The script for encoding a multiple-scan file is an array of these: */
183 
184 typedef struct {
185   int comps_in_scan;		/* number of components encoded in this scan */
186   int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */
187   int Ss, Se;			/* progressive JPEG spectral selection parms */
188   int Ah, Al;			/* progressive JPEG successive approx. parms */
189 } jpeg_scan_info;
190 
191 /* The decompressor can save APPn and COM markers in a list of these: */
192 
193 typedef struct jpeg_marker_struct FAR * jpeg_saved_marker_ptr;
194 
195 struct jpeg_marker_struct {
196   jpeg_saved_marker_ptr next;	/* next in list, or NULL */
197   UINT8 marker;			/* marker code: JPEG_COM, or JPEG_APP0+n */
198   unsigned int original_length;	/* # bytes of data in the file */
199   unsigned int data_length;	/* # bytes of data saved at data[] */
200   JOCTET FAR * data;		/* the data contained in the marker */
201   /* the marker length word is not counted in data_length or original_length */
202 };
203 
204 /* Known color spaces. */
205 
206 typedef enum {
207 	JCS_UNKNOWN,		/* error/unspecified */
208 	JCS_GRAYSCALE,		/* monochrome */
209 	JCS_RGB,		/* red/green/blue */
210 	JCS_YCbCr,		/* Y/Cb/Cr (also known as YUV) */
211 	JCS_CMYK,		/* C/M/Y/K */
212 	JCS_YCCK,		/* Y/Cb/Cr/K */
213 #ifdef ANDROID_RGB
214     JCS_RGBA_8888,  /* red/green/blue/alpha */
215     JCS_RGB_565     /* red/green/blue in 565 format */
216 #endif
217 } J_COLOR_SPACE;
218 
219 /* DCT/IDCT algorithm options. */
220 
221 typedef enum {
222 	JDCT_ISLOW,		/* slow but accurate integer algorithm */
223 	JDCT_IFAST,		/* faster, less accurate integer method */
224 	JDCT_FLOAT		/* floating-point: accurate, fast on fast HW */
225 } J_DCT_METHOD;
226 
227 #ifndef JDCT_DEFAULT		/* may be overridden in jconfig.h */
228 #define JDCT_DEFAULT  JDCT_ISLOW
229 #endif
230 #ifndef JDCT_FASTEST		/* may be overridden in jconfig.h */
231 #define JDCT_FASTEST  JDCT_IFAST
232 #endif
233 
234 /* Dithering options for decompression. */
235 
236 typedef enum {
237 	JDITHER_NONE,		/* no dithering */
238 	JDITHER_ORDERED,	/* simple ordered dither */
239 	JDITHER_FS		/* Floyd-Steinberg error diffusion dither */
240 } J_DITHER_MODE;
241 
242 
243 /* Common fields between JPEG compression and decompression master structs. */
244 
245 #define jpeg_common_fields \
246   struct jpeg_error_mgr * err;	/* Error handler module */\
247   struct jpeg_memory_mgr * mem;	/* Memory manager module */\
248   struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\
249   void * client_data;		/* Available for use by application */\
250   boolean is_decompressor;	/* So common code can tell which is which */\
251   int global_state		/* For checking call sequence validity */
252 
253 /* Routines that are to be used by both halves of the library are declared
254  * to receive a pointer to this structure.  There are no actual instances of
255  * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
256  */
257 struct jpeg_common_struct {
258   jpeg_common_fields;		/* Fields common to both master struct types */
259   /* Additional fields follow in an actual jpeg_compress_struct or
260    * jpeg_decompress_struct.  All three structs must agree on these
261    * initial fields!  (This would be a lot cleaner in C++.)
262    */
263 };
264 
265 typedef struct jpeg_common_struct * j_common_ptr;
266 typedef struct jpeg_compress_struct * j_compress_ptr;
267 typedef struct jpeg_decompress_struct * j_decompress_ptr;
268 
269 
270 /* Master record for a compression instance */
271 
272 struct jpeg_compress_struct {
273   jpeg_common_fields;		/* Fields shared with jpeg_decompress_struct */
274 
275   /* Destination for compressed data */
276   struct jpeg_destination_mgr * dest;
277 
278   /* Description of source image --- these fields must be filled in by
279    * outer application before starting compression.  in_color_space must
280    * be correct before you can even call jpeg_set_defaults().
281    */
282 
283   JDIMENSION image_width;	/* input image width */
284   JDIMENSION image_height;	/* input image height */
285   int input_components;		/* # of color components in input image */
286   J_COLOR_SPACE in_color_space;	/* colorspace of input image */
287 
288   double input_gamma;		/* image gamma of input image */
289 
290   /* Compression parameters --- these fields must be set before calling
291    * jpeg_start_compress().  We recommend calling jpeg_set_defaults() to
292    * initialize everything to reasonable defaults, then changing anything
293    * the application specifically wants to change.  That way you won't get
294    * burnt when new parameters are added.  Also note that there are several
295    * helper routines to simplify changing parameters.
296    */
297 
298   int data_precision;		/* bits of precision in image data */
299 
300   int num_components;		/* # of color components in JPEG image */
301   J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
302 
303   jpeg_component_info * comp_info;
304   /* comp_info[i] describes component that appears i'th in SOF */
305 
306   JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
307   /* ptrs to coefficient quantization tables, or NULL if not defined */
308 
309   JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
310   JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
311   /* ptrs to Huffman coding tables, or NULL if not defined */
312 
313   UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
314   UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
315   UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
316 
317   int num_scans;		/* # of entries in scan_info array */
318   const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */
319   /* The default value of scan_info is NULL, which causes a single-scan
320    * sequential JPEG file to be emitted.  To create a multi-scan file,
321    * set num_scans and scan_info to point to an array of scan definitions.
322    */
323 
324   boolean raw_data_in;		/* TRUE=caller supplies downsampled data */
325   boolean arith_code;		/* TRUE=arithmetic coding, FALSE=Huffman */
326   boolean optimize_coding;	/* TRUE=optimize entropy encoding parms */
327   boolean CCIR601_sampling;	/* TRUE=first samples are cosited */
328   int smoothing_factor;		/* 1..100, or 0 for no input smoothing */
329   J_DCT_METHOD dct_method;	/* DCT algorithm selector */
330 
331   /* The restart interval can be specified in absolute MCUs by setting
332    * restart_interval, or in MCU rows by setting restart_in_rows
333    * (in which case the correct restart_interval will be figured
334    * for each scan).
335    */
336   unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
337   int restart_in_rows;		/* if > 0, MCU rows per restart interval */
338 
339   /* Parameters controlling emission of special markers. */
340 
341   boolean write_JFIF_header;	/* should a JFIF marker be written? */
342   UINT8 JFIF_major_version;	/* What to write for the JFIF version number */
343   UINT8 JFIF_minor_version;
344   /* These three values are not used by the JPEG code, merely copied */
345   /* into the JFIF APP0 marker.  density_unit can be 0 for unknown, */
346   /* 1 for dots/inch, or 2 for dots/cm.  Note that the pixel aspect */
347   /* ratio is defined by X_density/Y_density even when density_unit=0. */
348   UINT8 density_unit;		/* JFIF code for pixel size units */
349   UINT16 X_density;		/* Horizontal pixel density */
350   UINT16 Y_density;		/* Vertical pixel density */
351   boolean write_Adobe_marker;	/* should an Adobe marker be written? */
352 
353   /* State variable: index of next scanline to be written to
354    * jpeg_write_scanlines().  Application may use this to control its
355    * processing loop, e.g., "while (next_scanline < image_height)".
356    */
357 
358   JDIMENSION next_scanline;	/* 0 .. image_height-1  */
359 
360   /* Remaining fields are known throughout compressor, but generally
361    * should not be touched by a surrounding application.
362    */
363 
364   /*
365    * These fields are computed during compression startup
366    */
367   boolean progressive_mode;	/* TRUE if scan script uses progressive mode */
368   int max_h_samp_factor;	/* largest h_samp_factor */
369   int max_v_samp_factor;	/* largest v_samp_factor */
370 
371   JDIMENSION total_iMCU_rows;	/* # of iMCU rows to be input to coef ctlr */
372   /* The coefficient controller receives data in units of MCU rows as defined
373    * for fully interleaved scans (whether the JPEG file is interleaved or not).
374    * There are v_samp_factor * DCTSIZE sample rows of each component in an
375    * "iMCU" (interleaved MCU) row.
376    */
377 
378   /*
379    * These fields are valid during any one scan.
380    * They describe the components and MCUs actually appearing in the scan.
381    */
382   int comps_in_scan;		/* # of JPEG components in this scan */
383   jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
384   /* *cur_comp_info[i] describes component that appears i'th in SOS */
385 
386   JDIMENSION MCUs_per_row;	/* # of MCUs across the image */
387   JDIMENSION MCU_rows_in_scan;	/* # of MCU rows in the image */
388 
389   int blocks_in_MCU;		/* # of DCT blocks per MCU */
390   int MCU_membership[C_MAX_BLOCKS_IN_MCU];
391   /* MCU_membership[i] is index in cur_comp_info of component owning */
392   /* i'th block in an MCU */
393 
394   int Ss, Se, Ah, Al;		/* progressive JPEG parameters for scan */
395 
396   /*
397    * Links to compression subobjects (methods and private variables of modules)
398    */
399   struct jpeg_comp_master * master;
400   struct jpeg_c_main_controller * main;
401   struct jpeg_c_prep_controller * prep;
402   struct jpeg_c_coef_controller * coef;
403   struct jpeg_marker_writer * marker;
404   struct jpeg_color_converter * cconvert;
405   struct jpeg_downsampler * downsample;
406   struct jpeg_forward_dct * fdct;
407   struct jpeg_entropy_encoder * entropy;
408   jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */
409   int script_space_size;
410 };
411 
412 
413 /* Master record for a decompression instance */
414 
415 struct jpeg_decompress_struct {
416   jpeg_common_fields;		/* Fields shared with jpeg_compress_struct */
417 
418   /* Source of compressed data */
419   struct jpeg_source_mgr * src;
420 
421   /* Basic description of image --- filled in by jpeg_read_header(). */
422   /* Application may inspect these values to decide how to process image. */
423 
424   JDIMENSION image_width;	/* nominal image width (from SOF marker) */
425   JDIMENSION image_height;	/* nominal image height */
426   int num_components;		/* # of color components in JPEG image */
427   J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
428 
429   /* Decompression processing parameters --- these fields must be set before
430    * calling jpeg_start_decompress().  Note that jpeg_read_header() initializes
431    * them to default values.
432    */
433 
434   J_COLOR_SPACE out_color_space; /* colorspace for output */
435 
436   unsigned int scale_num, scale_denom; /* fraction by which to scale image */
437 
438   double output_gamma;		/* image gamma wanted in output */
439 
440   boolean buffered_image;	/* TRUE=multiple output passes */
441   boolean raw_data_out;		/* TRUE=downsampled data wanted */
442 
443   J_DCT_METHOD dct_method;	/* IDCT algorithm selector */
444   boolean do_fancy_upsampling;	/* TRUE=apply fancy upsampling */
445   boolean do_block_smoothing;	/* TRUE=apply interblock smoothing */
446 
447   boolean quantize_colors;	/* TRUE=colormapped output wanted */
448   /* the following are ignored if not quantize_colors: */
449   J_DITHER_MODE dither_mode;	/* type of color dithering to use */
450   boolean two_pass_quantize;	/* TRUE=use two-pass color quantization */
451   int desired_number_of_colors;	/* max # colors to use in created colormap */
452   /* these are significant only in buffered-image mode: */
453   boolean enable_1pass_quant;	/* enable future use of 1-pass quantizer */
454   boolean enable_external_quant;/* enable future use of external colormap */
455   boolean enable_2pass_quant;	/* enable future use of 2-pass quantizer */
456 
457   /* Description of actual output image that will be returned to application.
458    * These fields are computed by jpeg_start_decompress().
459    * You can also use jpeg_calc_output_dimensions() to determine these values
460    * in advance of calling jpeg_start_decompress().
461    */
462 
463   JDIMENSION output_width;	/* scaled image width */
464   JDIMENSION output_height;	/* scaled image height */
465   int out_color_components;	/* # of color components in out_color_space */
466   int output_components;	/* # of color components returned */
467   /* output_components is 1 (a colormap index) when quantizing colors;
468    * otherwise it equals out_color_components.
469    */
470   int rec_outbuf_height;	/* min recommended height of scanline buffer */
471   /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
472    * high, space and time will be wasted due to unnecessary data copying.
473    * Usually rec_outbuf_height will be 1 or 2, at most 4.
474    */
475 
476   /* When quantizing colors, the output colormap is described by these fields.
477    * The application can supply a colormap by setting colormap non-NULL before
478    * calling jpeg_start_decompress; otherwise a colormap is created during
479    * jpeg_start_decompress or jpeg_start_output.
480    * The map has out_color_components rows and actual_number_of_colors columns.
481    */
482   int actual_number_of_colors;	/* number of entries in use */
483   JSAMPARRAY colormap;		/* The color map as a 2-D pixel array */
484 
485   /* State variables: these variables indicate the progress of decompression.
486    * The application may examine these but must not modify them.
487    */
488 
489   /* Row index of next scanline to be read from jpeg_read_scanlines().
490    * Application may use this to control its processing loop, e.g.,
491    * "while (output_scanline < output_height)".
492    */
493   JDIMENSION output_scanline;	/* 0 .. output_height-1  */
494 
495   /* Current input scan number and number of iMCU rows completed in scan.
496    * These indicate the progress of the decompressor input side.
497    */
498   int input_scan_number;	/* Number of SOS markers seen so far */
499   JDIMENSION input_iMCU_row;	/* Number of iMCU rows completed */
500 
501   /* The "output scan number" is the notional scan being displayed by the
502    * output side.  The decompressor will not allow output scan/row number
503    * to get ahead of input scan/row, but it can fall arbitrarily far behind.
504    */
505   int output_scan_number;	/* Nominal scan number being displayed */
506   JDIMENSION output_iMCU_row;	/* Number of iMCU rows read */
507 
508   /* Current progression status.  coef_bits[c][i] indicates the precision
509    * with which component c's DCT coefficient i (in zigzag order) is known.
510    * It is -1 when no data has yet been received, otherwise it is the point
511    * transform (shift) value for the most recent scan of the coefficient
512    * (thus, 0 at completion of the progression).
513    * This pointer is NULL when reading a non-progressive file.
514    */
515   int (*coef_bits)[DCTSIZE2];	/* -1 or current Al value for each coef */
516 
517   /* Internal JPEG parameters --- the application usually need not look at
518    * these fields.  Note that the decompressor output side may not use
519    * any parameters that can change between scans.
520    */
521 
522   /* Quantization and Huffman tables are carried forward across input
523    * datastreams when processing abbreviated JPEG datastreams.
524    */
525 
526   JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
527   /* ptrs to coefficient quantization tables, or NULL if not defined */
528 
529   JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
530   JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
531   /* ptrs to Huffman coding tables, or NULL if not defined */
532 
533   /* These parameters are never carried across datastreams, since they
534    * are given in SOF/SOS markers or defined to be reset by SOI.
535    */
536 
537   int data_precision;		/* bits of precision in image data */
538 
539   jpeg_component_info * comp_info;
540   /* comp_info[i] describes component that appears i'th in SOF */
541 
542   boolean progressive_mode;	/* TRUE if SOFn specifies progressive mode */
543   boolean arith_code;		/* TRUE=arithmetic coding, FALSE=Huffman */
544 
545   UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
546   UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
547   UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
548 
549   unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */
550 
551   /* These fields record data obtained from optional markers recognized by
552    * the JPEG library.
553    */
554   boolean saw_JFIF_marker;	/* TRUE iff a JFIF APP0 marker was found */
555   /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */
556   UINT8 JFIF_major_version;	/* JFIF version number */
557   UINT8 JFIF_minor_version;
558   UINT8 density_unit;		/* JFIF code for pixel size units */
559   UINT16 X_density;		/* Horizontal pixel density */
560   UINT16 Y_density;		/* Vertical pixel density */
561   boolean saw_Adobe_marker;	/* TRUE iff an Adobe APP14 marker was found */
562   UINT8 Adobe_transform;	/* Color transform code from Adobe marker */
563 
564   boolean CCIR601_sampling;	/* TRUE=first samples are cosited */
565 
566   /* Aside from the specific data retained from APPn markers known to the
567    * library, the uninterpreted contents of any or all APPn and COM markers
568    * can be saved in a list for examination by the application.
569    */
570   jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */
571 
572   /* Remaining fields are known throughout decompressor, but generally
573    * should not be touched by a surrounding application.
574    */
575 
576   /*
577    * These fields are computed during decompression startup
578    */
579   int max_h_samp_factor;	/* largest h_samp_factor */
580   int max_v_samp_factor;	/* largest v_samp_factor */
581 
582   int min_DCT_scaled_size;	/* smallest DCT_scaled_size of any component */
583 
584   JDIMENSION total_iMCU_rows;	/* # of iMCU rows in image */
585   /* The coefficient controller's input and output progress is measured in
586    * units of "iMCU" (interleaved MCU) rows.  These are the same as MCU rows
587    * in fully interleaved JPEG scans, but are used whether the scan is
588    * interleaved or not.  We define an iMCU row as v_samp_factor DCT block
589    * rows of each component.  Therefore, the IDCT output contains
590    * v_samp_factor*DCT_scaled_size sample rows of a component per iMCU row.
591    */
592 
593   JSAMPLE * sample_range_limit; /* table for fast range-limiting */
594 
595   /*
596    * These fields are valid during any one scan.
597    * They describe the components and MCUs actually appearing in the scan.
598    * Note that the decompressor output side must not use these fields.
599    */
600   int comps_in_scan;		/* # of JPEG components in this scan */
601   jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
602   /* *cur_comp_info[i] describes component that appears i'th in SOS */
603 
604   JDIMENSION MCUs_per_row;	/* # of MCUs across the image */
605   JDIMENSION MCU_rows_in_scan;	/* # of MCU rows in the image */
606 
607   int blocks_in_MCU;		/* # of DCT blocks per MCU */
608   int MCU_membership[D_MAX_BLOCKS_IN_MCU];
609   /* MCU_membership[i] is index in cur_comp_info of component owning */
610   /* i'th block in an MCU */
611 
612   int Ss, Se, Ah, Al;		/* progressive JPEG parameters for scan */
613 
614   /* This field is shared between entropy decoder and marker parser.
615    * It is either zero or the code of a JPEG marker that has been
616    * read from the data source, but has not yet been processed.
617    */
618   int unread_marker;
619 
620   /*
621    * Links to decompression subobjects (methods, private variables of modules)
622    */
623   struct jpeg_decomp_master * master;
624   struct jpeg_d_main_controller * main;
625   struct jpeg_d_coef_controller * coef;
626   struct jpeg_d_post_controller * post;
627   struct jpeg_input_controller * inputctl;
628   struct jpeg_marker_reader * marker;
629   struct jpeg_entropy_decoder * entropy;
630   struct jpeg_inverse_dct * idct;
631   struct jpeg_upsampler * upsample;
632   struct jpeg_color_deconverter * cconvert;
633   struct jpeg_color_quantizer * cquantize;
634 };
635 
636 
637 /* "Object" declarations for JPEG modules that may be supplied or called
638  * directly by the surrounding application.
639  * As with all objects in the JPEG library, these structs only define the
640  * publicly visible methods and state variables of a module.  Additional
641  * private fields may exist after the public ones.
642  */
643 
644 
645 /* Error handler object */
646 
647 struct jpeg_error_mgr {
648   /* Error exit handler: does not return to caller */
649   JMETHOD(void, error_exit, (j_common_ptr cinfo));
650   /* Conditionally emit a trace or warning message */
651   JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level));
652   /* Routine that actually outputs a trace or error message */
653   JMETHOD(void, output_message, (j_common_ptr cinfo));
654   /* Format a message string for the most recent JPEG error or message */
655   JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer));
656 #define JMSG_LENGTH_MAX  200	/* recommended size of format_message buffer */
657   /* Reset error state variables at start of a new image */
658   JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo));
659 
660   /* The message ID code and any parameters are saved here.
661    * A message can have one string parameter or up to 8 int parameters.
662    */
663   int msg_code;
664 #define JMSG_STR_PARM_MAX  80
665   union {
666     int i[8];
667     char s[JMSG_STR_PARM_MAX];
668   } msg_parm;
669 
670   /* Standard state variables for error facility */
671 
672   int trace_level;		/* max msg_level that will be displayed */
673 
674   /* For recoverable corrupt-data errors, we emit a warning message,
675    * but keep going unless emit_message chooses to abort.  emit_message
676    * should count warnings in num_warnings.  The surrounding application
677    * can check for bad data by seeing if num_warnings is nonzero at the
678    * end of processing.
679    */
680   long num_warnings;		/* number of corrupt-data warnings */
681 
682   /* These fields point to the table(s) of error message strings.
683    * An application can change the table pointer to switch to a different
684    * message list (typically, to change the language in which errors are
685    * reported).  Some applications may wish to add additional error codes
686    * that will be handled by the JPEG library error mechanism; the second
687    * table pointer is used for this purpose.
688    *
689    * First table includes all errors generated by JPEG library itself.
690    * Error code 0 is reserved for a "no such error string" message.
691    */
692   const char * const * jpeg_message_table; /* Library errors */
693   int last_jpeg_message;    /* Table contains strings 0..last_jpeg_message */
694   /* Second table can be added by application (see cjpeg/djpeg for example).
695    * It contains strings numbered first_addon_message..last_addon_message.
696    */
697   const char * const * addon_message_table; /* Non-library errors */
698   int first_addon_message;	/* code for first string in addon table */
699   int last_addon_message;	/* code for last string in addon table */
700 };
701 
702 
703 /* Progress monitor object */
704 
705 struct jpeg_progress_mgr {
706   JMETHOD(void, progress_monitor, (j_common_ptr cinfo));
707 
708   long pass_counter;		/* work units completed in this pass */
709   long pass_limit;		/* total number of work units in this pass */
710   int completed_passes;		/* passes completed so far */
711   int total_passes;		/* total number of passes expected */
712 };
713 
714 
715 /* Data destination object for compression */
716 
717 struct jpeg_destination_mgr {
718   JOCTET * next_output_byte;	/* => next byte to write in buffer */
719   size_t free_in_buffer;	/* # of byte spaces remaining in buffer */
720 
721   JMETHOD(void, init_destination, (j_compress_ptr cinfo));
722   JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo));
723   JMETHOD(void, term_destination, (j_compress_ptr cinfo));
724 };
725 
726 
727 /* Data source object for decompression */
728 
729 struct jpeg_source_mgr {
730   const JOCTET * next_input_byte; /* => next byte to read from buffer */
731   size_t bytes_in_buffer;	/* # of bytes remaining in buffer */
732 
733   JMETHOD(void, init_source, (j_decompress_ptr cinfo));
734   JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo));
735   JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes));
736   JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired));
737   JMETHOD(void, term_source, (j_decompress_ptr cinfo));
738 };
739 
740 
741 /* Memory manager object.
742  * Allocates "small" objects (a few K total), "large" objects (tens of K),
743  * and "really big" objects (virtual arrays with backing store if needed).
744  * The memory manager does not allow individual objects to be freed; rather,
745  * each created object is assigned to a pool, and whole pools can be freed
746  * at once.  This is faster and more convenient than remembering exactly what
747  * to free, especially where malloc()/free() are not too speedy.
748  * NB: alloc routines never return NULL.  They exit to error_exit if not
749  * successful.
750  */
751 
752 #define JPOOL_PERMANENT	0	/* lasts until master record is destroyed */
753 #define JPOOL_IMAGE	1	/* lasts until done with image/datastream */
754 #define JPOOL_NUMPOOLS	2
755 
756 typedef struct jvirt_sarray_control * jvirt_sarray_ptr;
757 typedef struct jvirt_barray_control * jvirt_barray_ptr;
758 
759 
760 struct jpeg_memory_mgr {
761   /* Method pointers */
762   JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id,
763 				size_t sizeofobject));
764   JMETHOD(void FAR *, alloc_large, (j_common_ptr cinfo, int pool_id,
765 				     size_t sizeofobject));
766   JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id,
767 				     JDIMENSION samplesperrow,
768 				     JDIMENSION numrows));
769   JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id,
770 				      JDIMENSION blocksperrow,
771 				      JDIMENSION numrows));
772   JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo,
773 						  int pool_id,
774 						  boolean pre_zero,
775 						  JDIMENSION samplesperrow,
776 						  JDIMENSION numrows,
777 						  JDIMENSION maxaccess));
778   JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,
779 						  int pool_id,
780 						  boolean pre_zero,
781 						  JDIMENSION blocksperrow,
782 						  JDIMENSION numrows,
783 						  JDIMENSION maxaccess));
784   JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo));
785   JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo,
786 					   jvirt_sarray_ptr ptr,
787 					   JDIMENSION start_row,
788 					   JDIMENSION num_rows,
789 					   boolean writable));
790   JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,
791 					    jvirt_barray_ptr ptr,
792 					    JDIMENSION start_row,
793 					    JDIMENSION num_rows,
794 					    boolean writable));
795   JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id));
796   JMETHOD(void, self_destruct, (j_common_ptr cinfo));
797 
798   /* Limit on memory allocation for this JPEG object.  (Note that this is
799    * merely advisory, not a guaranteed maximum; it only affects the space
800    * used for virtual-array buffers.)  May be changed by outer application
801    * after creating the JPEG object.
802    */
803   long max_memory_to_use;
804 
805   /* Maximum allocation request accepted by alloc_large. */
806   long max_alloc_chunk;
807 };
808 
809 
810 /* Routine signature for application-supplied marker processing methods.
811  * Need not pass marker code since it is stored in cinfo->unread_marker.
812  */
813 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo));
814 
815 
816 /* Declarations for routines called by application.
817  * The JPP macro hides prototype parameters from compilers that can't cope.
818  * Note JPP requires double parentheses.
819  */
820 
821 #ifdef HAVE_PROTOTYPES
822 #define JPP(arglist)	arglist
823 #else
824 #define JPP(arglist)	()
825 #endif
826 
827 
828 /* Short forms of external names for systems with brain-damaged linkers.
829  * We shorten external names to be unique in the first six letters, which
830  * is good enough for all known systems.
831  * (If your compiler itself needs names to be unique in less than 15
832  * characters, you are out of luck.  Get a better compiler.)
833  */
834 
835 #ifdef NEED_SHORT_EXTERNAL_NAMES
836 #define jpeg_std_error		jStdError
837 #define jpeg_CreateCompress	jCreaCompress
838 #define jpeg_CreateDecompress	jCreaDecompress
839 #define jpeg_destroy_compress	jDestCompress
840 #define jpeg_destroy_decompress	jDestDecompress
841 #define jpeg_stdio_dest		jStdDest
842 #define jpeg_stdio_src		jStdSrc
843 #define jpeg_set_defaults	jSetDefaults
844 #define jpeg_set_colorspace	jSetColorspace
845 #define jpeg_default_colorspace	jDefColorspace
846 #define jpeg_set_quality	jSetQuality
847 #define jpeg_set_linear_quality	jSetLQuality
848 #define jpeg_add_quant_table	jAddQuantTable
849 #define jpeg_quality_scaling	jQualityScaling
850 #define jpeg_simple_progression	jSimProgress
851 #define jpeg_suppress_tables	jSuppressTables
852 #define jpeg_alloc_quant_table	jAlcQTable
853 #define jpeg_alloc_huff_table	jAlcHTable
854 #define jpeg_start_compress	jStrtCompress
855 #define jpeg_write_scanlines	jWrtScanlines
856 #define jpeg_finish_compress	jFinCompress
857 #define jpeg_write_raw_data	jWrtRawData
858 #define jpeg_write_marker	jWrtMarker
859 #define jpeg_write_m_header	jWrtMHeader
860 #define jpeg_write_m_byte	jWrtMByte
861 #define jpeg_write_tables	jWrtTables
862 #define jpeg_read_header	jReadHeader
863 #define jpeg_start_decompress	jStrtDecompress
864 #define jpeg_read_scanlines	jReadScanlines
865 #define jpeg_finish_decompress	jFinDecompress
866 #define jpeg_read_raw_data	jReadRawData
867 #define jpeg_has_multiple_scans	jHasMultScn
868 #define jpeg_start_output	jStrtOutput
869 #define jpeg_finish_output	jFinOutput
870 #define jpeg_input_complete	jInComplete
871 #define jpeg_new_colormap	jNewCMap
872 #define jpeg_consume_input	jConsumeInput
873 #define jpeg_calc_output_dimensions	jCalcDimensions
874 #define jpeg_save_markers	jSaveMarkers
875 #define jpeg_set_marker_processor	jSetMarker
876 #define jpeg_read_coefficients	jReadCoefs
877 #define jpeg_write_coefficients	jWrtCoefs
878 #define jpeg_copy_critical_parameters	jCopyCrit
879 #define jpeg_abort_compress	jAbrtCompress
880 #define jpeg_abort_decompress	jAbrtDecompress
881 #define jpeg_abort		jAbort
882 #define jpeg_destroy		jDestroy
883 #define jpeg_resync_to_restart	jResyncRestart
884 #endif /* NEED_SHORT_EXTERNAL_NAMES */
885 
886 
887 /* Default error-management setup */
888 EXTERN(struct jpeg_error_mgr *) jpeg_std_error
889 	JPP((struct jpeg_error_mgr * err));
890 
891 /* Initialization of JPEG compression objects.
892  * jpeg_create_compress() and jpeg_create_decompress() are the exported
893  * names that applications should call.  These expand to calls on
894  * jpeg_CreateCompress and jpeg_CreateDecompress with additional information
895  * passed for version mismatch checking.
896  * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx.
897  */
898 #define jpeg_create_compress(cinfo) \
899     jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \
900 			(size_t) sizeof(struct jpeg_compress_struct))
901 #define jpeg_create_decompress(cinfo) \
902     jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \
903 			  (size_t) sizeof(struct jpeg_decompress_struct))
904 EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo,
905 				      int version, size_t structsize));
906 EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo,
907 					int version, size_t structsize));
908 /* Destruction of JPEG compression objects */
909 EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo));
910 EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo));
911 
912 /* Standard data source and destination managers: stdio streams. */
913 /* Caller is responsible for opening the file before and closing after. */
914 EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FILE * outfile));
915 EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FILE * infile));
916 
917 /* Default parameter setup for compression */
918 EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo));
919 /* Compression parameter setup aids */
920 EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo,
921 				      J_COLOR_SPACE colorspace));
922 EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo));
923 EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,
924 				   boolean force_baseline));
925 EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo,
926 					  int scale_factor,
927 					  boolean force_baseline));
928 EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,
929 				       const unsigned int *basic_table,
930 				       int scale_factor,
931 				       boolean force_baseline));
932 EXTERN(int) jpeg_quality_scaling JPP((int quality));
933 EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo));
934 EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo,
935 				       boolean suppress));
936 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo));
937 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo));
938 
939 /* Main entry points for compression */
940 EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo,
941 				      boolean write_all_tables));
942 EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo,
943 					     JSAMPARRAY scanlines,
944 					     JDIMENSION num_lines));
945 EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo));
946 
947 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
948 EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo,
949 					    JSAMPIMAGE data,
950 					    JDIMENSION num_lines));
951 
952 /* Write a special marker.  See libjpeg.doc concerning safe usage. */
953 EXTERN(void) jpeg_write_marker
954 	JPP((j_compress_ptr cinfo, int marker,
955 	     const JOCTET * dataptr, unsigned int datalen));
956 /* Same, but piecemeal. */
957 EXTERN(void) jpeg_write_m_header
958 	JPP((j_compress_ptr cinfo, int marker, unsigned int datalen));
959 EXTERN(void) jpeg_write_m_byte
960 	JPP((j_compress_ptr cinfo, int val));
961 
962 /* Alternate compression function: just write an abbreviated table file */
963 EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo));
964 
965 /* Decompression startup: read start of JPEG datastream to see what's there */
966 EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo,
967 				  boolean require_image));
968 /* Return value is one of: */
969 #define JPEG_SUSPENDED		0 /* Suspended due to lack of input data */
970 #define JPEG_HEADER_OK		1 /* Found valid image datastream */
971 #define JPEG_HEADER_TABLES_ONLY	2 /* Found valid table-specs-only datastream */
972 /* If you pass require_image = TRUE (normal case), you need not check for
973  * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
974  * JPEG_SUSPENDED is only possible if you use a data source module that can
975  * give a suspension return (the stdio source module doesn't).
976  */
977 
978 /* Main entry points for decompression */
979 EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo));
980 EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo,
981 					    JSAMPARRAY scanlines,
982 					    JDIMENSION max_lines));
983 EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo));
984 
985 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
986 EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo,
987 					   JSAMPIMAGE data,
988 					   JDIMENSION max_lines));
989 
990 /* Additional entry points for buffered-image mode. */
991 EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo));
992 EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo,
993 				       int scan_number));
994 EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo));
995 EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo));
996 EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo));
997 EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo));
998 /* Return value is one of: */
999 /* #define JPEG_SUSPENDED	0    Suspended due to lack of input data */
1000 #define JPEG_REACHED_SOS	1 /* Reached start of new scan */
1001 #define JPEG_REACHED_EOI	2 /* Reached end of image */
1002 #define JPEG_ROW_COMPLETED	3 /* Completed one iMCU row */
1003 #define JPEG_SCAN_COMPLETED	4 /* Completed last iMCU row of a scan */
1004 
1005 /* Precalculate output dimensions for current decompression parameters. */
1006 EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));
1007 
1008 /* Control saving of COM and APPn markers into marker_list. */
1009 EXTERN(void) jpeg_save_markers
1010 	JPP((j_decompress_ptr cinfo, int marker_code,
1011 	     unsigned int length_limit));
1012 
1013 /* Install a special processing method for COM or APPn markers. */
1014 EXTERN(void) jpeg_set_marker_processor
1015 	JPP((j_decompress_ptr cinfo, int marker_code,
1016 	     jpeg_marker_parser_method routine));
1017 
1018 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */
1019 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo));
1020 EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo,
1021 					  jvirt_barray_ptr * coef_arrays));
1022 EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo,
1023 						j_compress_ptr dstinfo));
1024 
1025 /* If you choose to abort compression or decompression before completing
1026  * jpeg_finish_(de)compress, then you need to clean up to release memory,
1027  * temporary files, etc.  You can just call jpeg_destroy_(de)compress
1028  * if you're done with the JPEG object, but if you want to clean it up and
1029  * reuse it, call this:
1030  */
1031 EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo));
1032 EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo));
1033 
1034 /* Generic versions of jpeg_abort and jpeg_destroy that work on either
1035  * flavor of JPEG object.  These may be more convenient in some places.
1036  */
1037 EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo));
1038 EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo));
1039 
1040 /* Default restart-marker-resync procedure for use by data source modules */
1041 EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo,
1042 					    int desired));
1043 
1044 
1045 /* These marker codes are exported since applications and data source modules
1046  * are likely to want to use them.
1047  */
1048 
1049 #define JPEG_RST0	0xD0	/* RST0 marker code */
1050 #define JPEG_EOI	0xD9	/* EOI marker code */
1051 #define JPEG_APP0	0xE0	/* APP0 marker code */
1052 #define JPEG_COM	0xFE	/* COM marker code */
1053 
1054 
1055 /* If we have a brain-damaged compiler that emits warnings (or worse, errors)
1056  * for structure definitions that are never filled in, keep it quiet by
1057  * supplying dummy definitions for the various substructures.
1058  */
1059 
1060 #ifdef INCOMPLETE_TYPES_BROKEN
1061 #ifndef JPEG_INTERNALS		/* will be defined in jpegint.h */
1062 struct jvirt_sarray_control { long dummy; };
1063 struct jvirt_barray_control { long dummy; };
1064 struct jpeg_comp_master { long dummy; };
1065 struct jpeg_c_main_controller { long dummy; };
1066 struct jpeg_c_prep_controller { long dummy; };
1067 struct jpeg_c_coef_controller { long dummy; };
1068 struct jpeg_marker_writer { long dummy; };
1069 struct jpeg_color_converter { long dummy; };
1070 struct jpeg_downsampler { long dummy; };
1071 struct jpeg_forward_dct { long dummy; };
1072 struct jpeg_entropy_encoder { long dummy; };
1073 struct jpeg_decomp_master { long dummy; };
1074 struct jpeg_d_main_controller { long dummy; };
1075 struct jpeg_d_coef_controller { long dummy; };
1076 struct jpeg_d_post_controller { long dummy; };
1077 struct jpeg_input_controller { long dummy; };
1078 struct jpeg_marker_reader { long dummy; };
1079 struct jpeg_entropy_decoder { long dummy; };
1080 struct jpeg_inverse_dct { long dummy; };
1081 struct jpeg_upsampler { long dummy; };
1082 struct jpeg_color_deconverter { long dummy; };
1083 struct jpeg_color_quantizer { long dummy; };
1084 #endif /* JPEG_INTERNALS */
1085 #endif /* INCOMPLETE_TYPES_BROKEN */
1086 
1087 
1088 /*
1089  * The JPEG library modules define JPEG_INTERNALS before including this file.
1090  * The internal structure declarations are read only when that is true.
1091  * Applications using the library should not include jpegint.h, but may wish
1092  * to include jerror.h.
1093  */
1094 
1095 #ifdef JPEG_INTERNALS
1096 #include "jpegint.h"		/* fetch private declarations */
1097 #include "jerror.h"		/* fetch error codes too */
1098 #endif
1099 
1100 #endif /* JPEGLIB_H */
1101