4 * Copyright (C) 1991-1998, Thomas G. Lane.
5 * Modified 2002-2009 by Guido Vollbeding.
6 * This file is part of the Independent JPEG Group's software.
7 * For conditions of distribution and use, see the accompanying README file.
9 * This file defines the application interface for the JPEG library.
10 * Most applications using the library need only include this file,
11 * and perhaps jerror.h if they want to know the exact error codes.
18 * First we include the configuration files that record how this
19 * installation of the JPEG library is set up. jconfig.h can be
20 * generated automatically for many systems. jmorecfg.h contains
21 * manual configuration options that most people need not worry about.
24 #ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */
25 #include "jconfig.h" /* widely used configuration options */
27 #include "jmorecfg.h" /* seldom changed options */
31 #ifndef DONT_USE_EXTERN_C
36 /* Version ID for the JPEG library.
37 * Might be useful for tests like "#if JPEG_LIB_VERSION >= 80".
40 #define JPEG_LIB_VERSION 80 /* Version 8.0 */
43 /* Various constants determining the sizes of things.
44 * All of these are specified by the JPEG standard, so don't change them
45 * if you want to be compatible.
48 #define DCTSIZE 8 /* The basic DCT block is 8x8 samples */
49 #define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */
50 #define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */
51 #define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */
52 #define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */
53 #define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */
54 #define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */
55 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
56 * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
57 * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
58 * to handle it. We even let you do this from the jconfig.h file. However,
59 * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
60 * sometimes emits noncompliant files doesn't mean you should too.
62 #define C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on blocks per MCU */
63 #ifndef D_MAX_BLOCKS_IN_MCU
64 #define D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on blocks per MCU */
68 /* Data structures for images (arrays of samples and of DCT coefficients).
69 * On 80x86 machines, the image arrays are too big for near pointers,
70 * but the pointer arrays can fit in near memory.
73 typedef JSAMPLE FAR
*JSAMPROW
; /* ptr to one image row of pixel samples. */
74 typedef JSAMPROW
*JSAMPARRAY
; /* ptr to some rows (a 2-D sample array) */
75 typedef JSAMPARRAY
*JSAMPIMAGE
; /* a 3-D sample array: top index is color */
77 typedef JCOEF JBLOCK
[DCTSIZE2
]; /* one block of coefficients */
78 typedef JBLOCK FAR
*JBLOCKROW
; /* pointer to one row of coefficient blocks */
79 typedef JBLOCKROW
*JBLOCKARRAY
; /* a 2-D array of coefficient blocks */
80 typedef JBLOCKARRAY
*JBLOCKIMAGE
; /* a 3-D array of coefficient blocks */
82 typedef JCOEF FAR
*JCOEFPTR
; /* useful in a couple of places */
85 /* Types for JPEG compression parameters and working tables. */
88 /* DCT coefficient quantization tables. */
91 /* This array gives the coefficient quantizers in natural array order
92 * (not the zigzag order in which they are stored in a JPEG DQT marker).
93 * CAUTION: IJG versions prior to v6a kept this array in zigzag order.
95 UINT16 quantval
[DCTSIZE2
]; /* quantization step for each coefficient */
96 /* This field is used only during compression. It's initialized FALSE when
97 * the table is created, and set TRUE when it's been output to the file.
98 * You could suppress output of a table by setting this to TRUE.
99 * (See jpeg_suppress_tables for an example.)
101 boolean sent_table
; /* TRUE when table has been output */
105 /* Huffman coding tables. */
108 /* These two fields directly represent the contents of a JPEG DHT marker */
109 UINT8 bits
[17]; /* bits[k] = # of symbols with codes of */
110 /* length k bits; bits[0] is unused */
111 UINT8 huffval
[256]; /* The symbols, in order of incr code length */
112 /* This field is used only during compression. It's initialized FALSE when
113 * the table is created, and set TRUE when it's been output to the file.
114 * You could suppress output of a table by setting this to TRUE.
115 * (See jpeg_suppress_tables for an example.)
117 boolean sent_table
; /* TRUE when table has been output */
121 /* Basic info about one component (color channel). */
124 /* These values are fixed over the whole image. */
125 /* For compression, they must be supplied by parameter setup; */
126 /* for decompression, they are read from the SOF marker. */
127 int component_id
; /* identifier for this component (0..255) */
128 int component_index
; /* its index in SOF or cinfo->comp_info[] */
129 int h_samp_factor
; /* horizontal sampling factor (1..4) */
130 int v_samp_factor
; /* vertical sampling factor (1..4) */
131 int quant_tbl_no
; /* quantization table selector (0..3) */
132 /* These values may vary between scans. */
133 /* For compression, they must be supplied by parameter setup; */
134 /* for decompression, they are read from the SOS marker. */
135 /* The decompressor output side may not use these variables. */
136 int dc_tbl_no
; /* DC entropy table selector (0..3) */
137 int ac_tbl_no
; /* AC entropy table selector (0..3) */
139 /* Remaining fields should be treated as private by applications. */
141 /* These values are computed during compression or decompression startup: */
142 /* Component's size in DCT blocks.
143 * Any dummy blocks added to complete an MCU are not counted; therefore
144 * these values do not depend on whether a scan is interleaved or not.
146 JDIMENSION width_in_blocks
;
147 JDIMENSION height_in_blocks
;
148 /* Size of a DCT block in samples,
149 * reflecting any scaling we choose to apply during the DCT step.
150 * Values from 1 to 16 are supported.
151 * Note that different components may receive different DCT scalings.
153 int DCT_h_scaled_size
;
154 int DCT_v_scaled_size
;
155 /* The downsampled dimensions are the component's actual, unpadded number
156 * of samples at the main buffer (preprocessing/compression interface);
157 * DCT scaling is included, so
158 * downsampled_width = ceil(image_width * Hi/Hmax * DCT_h_scaled_size/DCTSIZE)
159 * and similarly for height.
161 JDIMENSION downsampled_width
; /* actual width in samples */
162 JDIMENSION downsampled_height
; /* actual height in samples */
163 /* This flag is used only for decompression. In cases where some of the
164 * components will be ignored (eg grayscale output from YCbCr image),
165 * we can skip most computations for the unused components.
167 boolean component_needed
; /* do we need the value of this component? */
169 /* These values are computed before starting a scan of the component. */
170 /* The decompressor output side may not use these variables. */
171 int MCU_width
; /* number of blocks per MCU, horizontally */
172 int MCU_height
; /* number of blocks per MCU, vertically */
173 int MCU_blocks
; /* MCU_width * MCU_height */
174 int MCU_sample_width
; /* MCU width in samples: MCU_width * DCT_h_scaled_size */
175 int last_col_width
; /* # of non-dummy blocks across in last MCU */
176 int last_row_height
; /* # of non-dummy blocks down in last MCU */
178 /* Saved quantization table for component; NULL if none yet saved.
179 * See jdinput.c comments about the need for this information.
180 * This field is currently used only for decompression.
182 JQUANT_TBL
* quant_table
;
184 /* Private per-component storage for DCT or IDCT subsystem. */
186 } jpeg_component_info
;
189 /* The script for encoding a multiple-scan file is an array of these: */
192 int comps_in_scan
; /* number of components encoded in this scan */
193 int component_index
[MAX_COMPS_IN_SCAN
]; /* their SOF/comp_info[] indexes */
194 int Ss
, Se
; /* progressive JPEG spectral selection parms */
195 int Ah
, Al
; /* progressive JPEG successive approx. parms */
198 /* The decompressor can save APPn and COM markers in a list of these: */
200 typedef struct jpeg_marker_struct FAR
* jpeg_saved_marker_ptr
;
202 struct jpeg_marker_struct
{
203 jpeg_saved_marker_ptr next
; /* next in list, or NULL */
204 UINT8 marker
; /* marker code: JPEG_COM, or JPEG_APP0+n */
205 unsigned int original_length
; /* # bytes of data in the file */
206 unsigned int data_length
; /* # bytes of data saved at data[] */
207 JOCTET FAR
* data
; /* the data contained in the marker */
208 /* the marker length word is not counted in data_length or original_length */
211 /* Known color spaces. */
214 JCS_UNKNOWN
, /* error/unspecified */
215 JCS_GRAYSCALE
, /* monochrome */
216 JCS_RGB
, /* red/green/blue */
217 JCS_YCbCr
, /* Y/Cb/Cr (also known as YUV) */
218 JCS_CMYK
, /* C/M/Y/K */
219 JCS_YCCK
/* Y/Cb/Cr/K */
222 /* DCT/IDCT algorithm options. */
225 JDCT_ISLOW
, /* slow but accurate integer algorithm */
226 JDCT_IFAST
, /* faster, less accurate integer method */
227 JDCT_FLOAT
/* floating-point: accurate, fast on fast HW */
230 #ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */
231 #define JDCT_DEFAULT JDCT_ISLOW
233 #ifndef JDCT_FASTEST /* may be overridden in jconfig.h */
234 #define JDCT_FASTEST JDCT_IFAST
237 /* Dithering options for decompression. */
240 JDITHER_NONE
, /* no dithering */
241 JDITHER_ORDERED
, /* simple ordered dither */
242 JDITHER_FS
/* Floyd-Steinberg error diffusion dither */
246 /* Common fields between JPEG compression and decompression master structs. */
248 #define jpeg_common_fields \
249 struct jpeg_error_mgr * err; /* Error handler module */\
250 struct jpeg_memory_mgr * mem; /* Memory manager module */\
251 struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\
252 void * client_data; /* Available for use by application */\
253 boolean is_decompressor; /* So common code can tell which is which */\
254 int global_state /* For checking call sequence validity */
256 /* Routines that are to be used by both halves of the library are declared
257 * to receive a pointer to this structure. There are no actual instances of
258 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
260 struct jpeg_common_struct
{
261 jpeg_common_fields
; /* Fields common to both master struct types */
262 /* Additional fields follow in an actual jpeg_compress_struct or
263 * jpeg_decompress_struct. All three structs must agree on these
264 * initial fields! (This would be a lot cleaner in C++.)
268 typedef struct jpeg_common_struct
* j_common_ptr
;
269 typedef struct jpeg_compress_struct
* j_compress_ptr
;
270 typedef struct jpeg_decompress_struct
* j_decompress_ptr
;
273 /* Master record for a compression instance */
275 struct jpeg_compress_struct
{
276 jpeg_common_fields
; /* Fields shared with jpeg_decompress_struct */
278 /* Destination for compressed data */
279 struct jpeg_destination_mgr
* dest
;
281 /* Description of source image --- these fields must be filled in by
282 * outer application before starting compression. in_color_space must
283 * be correct before you can even call jpeg_set_defaults().
286 JDIMENSION image_width
; /* input image width */
287 JDIMENSION image_height
; /* input image height */
288 int input_components
; /* # of color components in input image */
289 J_COLOR_SPACE in_color_space
; /* colorspace of input image */
291 double input_gamma
; /* image gamma of input image */
293 /* Compression parameters --- these fields must be set before calling
294 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to
295 * initialize everything to reasonable defaults, then changing anything
296 * the application specifically wants to change. That way you won't get
297 * burnt when new parameters are added. Also note that there are several
298 * helper routines to simplify changing parameters.
301 unsigned int scale_num
, scale_denom
; /* fraction by which to scale image */
303 JDIMENSION jpeg_width
; /* scaled JPEG image width */
304 JDIMENSION jpeg_height
; /* scaled JPEG image height */
305 /* Dimensions of actual JPEG image that will be written to file,
306 * derived from input dimensions by scaling factors above.
307 * These fields are computed by jpeg_start_compress().
308 * You can also use jpeg_calc_jpeg_dimensions() to determine these values
309 * in advance of calling jpeg_start_compress().
312 int data_precision
; /* bits of precision in image data */
314 int num_components
; /* # of color components in JPEG image */
315 J_COLOR_SPACE jpeg_color_space
; /* colorspace of JPEG image */
317 jpeg_component_info
* comp_info
;
318 /* comp_info[i] describes component that appears i'th in SOF */
320 JQUANT_TBL
* quant_tbl_ptrs
[NUM_QUANT_TBLS
];
321 int q_scale_factor
[NUM_QUANT_TBLS
];
322 /* ptrs to coefficient quantization tables, or NULL if not defined,
323 * and corresponding scale factors (percentage, initialized 100).
326 JHUFF_TBL
* dc_huff_tbl_ptrs
[NUM_HUFF_TBLS
];
327 JHUFF_TBL
* ac_huff_tbl_ptrs
[NUM_HUFF_TBLS
];
328 /* ptrs to Huffman coding tables, or NULL if not defined */
330 UINT8 arith_dc_L
[NUM_ARITH_TBLS
]; /* L values for DC arith-coding tables */
331 UINT8 arith_dc_U
[NUM_ARITH_TBLS
]; /* U values for DC arith-coding tables */
332 UINT8 arith_ac_K
[NUM_ARITH_TBLS
]; /* Kx values for AC arith-coding tables */
334 int num_scans
; /* # of entries in scan_info array */
335 const jpeg_scan_info
* scan_info
; /* script for multi-scan file, or NULL */
336 /* The default value of scan_info is NULL, which causes a single-scan
337 * sequential JPEG file to be emitted. To create a multi-scan file,
338 * set num_scans and scan_info to point to an array of scan definitions.
341 boolean raw_data_in
; /* TRUE=caller supplies downsampled data */
342 boolean arith_code
; /* TRUE=arithmetic coding, FALSE=Huffman */
343 boolean optimize_coding
; /* TRUE=optimize entropy encoding parms */
344 boolean CCIR601_sampling
; /* TRUE=first samples are cosited */
345 boolean do_fancy_downsampling
; /* TRUE=apply fancy downsampling */
346 int smoothing_factor
; /* 1..100, or 0 for no input smoothing */
347 J_DCT_METHOD dct_method
; /* DCT algorithm selector */
349 /* The restart interval can be specified in absolute MCUs by setting
350 * restart_interval, or in MCU rows by setting restart_in_rows
351 * (in which case the correct restart_interval will be figured
354 unsigned int restart_interval
; /* MCUs per restart, or 0 for no restart */
355 int restart_in_rows
; /* if > 0, MCU rows per restart interval */
357 /* Parameters controlling emission of special markers. */
359 boolean write_JFIF_header
; /* should a JFIF marker be written? */
360 UINT8 JFIF_major_version
; /* What to write for the JFIF version number */
361 UINT8 JFIF_minor_version
;
362 /* These three values are not used by the JPEG code, merely copied */
363 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */
364 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */
365 /* ratio is defined by X_density/Y_density even when density_unit=0. */
366 UINT8 density_unit
; /* JFIF code for pixel size units */
367 UINT16 X_density
; /* Horizontal pixel density */
368 UINT16 Y_density
; /* Vertical pixel density */
369 boolean write_Adobe_marker
; /* should an Adobe marker be written? */
371 /* State variable: index of next scanline to be written to
372 * jpeg_write_scanlines(). Application may use this to control its
373 * processing loop, e.g., "while (next_scanline < image_height)".
376 JDIMENSION next_scanline
; /* 0 .. image_height-1 */
378 /* Remaining fields are known throughout compressor, but generally
379 * should not be touched by a surrounding application.
383 * These fields are computed during compression startup
385 boolean progressive_mode
; /* TRUE if scan script uses progressive mode */
386 int max_h_samp_factor
; /* largest h_samp_factor */
387 int max_v_samp_factor
; /* largest v_samp_factor */
389 int min_DCT_h_scaled_size
; /* smallest DCT_h_scaled_size of any component */
390 int min_DCT_v_scaled_size
; /* smallest DCT_v_scaled_size of any component */
392 JDIMENSION total_iMCU_rows
; /* # of iMCU rows to be input to coef ctlr */
393 /* The coefficient controller receives data in units of MCU rows as defined
394 * for fully interleaved scans (whether the JPEG file is interleaved or not).
395 * There are v_samp_factor * DCTSIZE sample rows of each component in an
396 * "iMCU" (interleaved MCU) row.
400 * These fields are valid during any one scan.
401 * They describe the components and MCUs actually appearing in the scan.
403 int comps_in_scan
; /* # of JPEG components in this scan */
404 jpeg_component_info
* cur_comp_info
[MAX_COMPS_IN_SCAN
];
405 /* *cur_comp_info[i] describes component that appears i'th in SOS */
407 JDIMENSION MCUs_per_row
; /* # of MCUs across the image */
408 JDIMENSION MCU_rows_in_scan
; /* # of MCU rows in the image */
410 int blocks_in_MCU
; /* # of DCT blocks per MCU */
411 int MCU_membership
[C_MAX_BLOCKS_IN_MCU
];
412 /* MCU_membership[i] is index in cur_comp_info of component owning */
413 /* i'th block in an MCU */
415 int Ss
, Se
, Ah
, Al
; /* progressive JPEG parameters for scan */
417 int block_size
; /* the basic DCT block size: 1..16 */
418 const int * natural_order
; /* natural-order position array */
419 int lim_Se
; /* min( Se, DCTSIZE2-1 ) */
422 * Links to compression subobjects (methods and private variables of modules)
424 struct jpeg_comp_master
* master
;
425 struct jpeg_c_main_controller
* main
;
426 struct jpeg_c_prep_controller
* prep
;
427 struct jpeg_c_coef_controller
* coef
;
428 struct jpeg_marker_writer
* marker
;
429 struct jpeg_color_converter
* cconvert
;
430 struct jpeg_downsampler
* downsample
;
431 struct jpeg_forward_dct
* fdct
;
432 struct jpeg_entropy_encoder
* entropy
;
433 jpeg_scan_info
* script_space
; /* workspace for jpeg_simple_progression */
434 int script_space_size
;
438 /* Master record for a decompression instance */
440 struct jpeg_decompress_struct
{
441 jpeg_common_fields
; /* Fields shared with jpeg_compress_struct */
443 /* Source of compressed data */
444 struct jpeg_source_mgr
* src
;
446 /* Basic description of image --- filled in by jpeg_read_header(). */
447 /* Application may inspect these values to decide how to process image. */
449 JDIMENSION image_width
; /* nominal image width (from SOF marker) */
450 JDIMENSION image_height
; /* nominal image height */
451 int num_components
; /* # of color components in JPEG image */
452 J_COLOR_SPACE jpeg_color_space
; /* colorspace of JPEG image */
454 /* Decompression processing parameters --- these fields must be set before
455 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes
456 * them to default values.
459 J_COLOR_SPACE out_color_space
; /* colorspace for output */
461 unsigned int scale_num
, scale_denom
; /* fraction by which to scale image */
463 double output_gamma
; /* image gamma wanted in output */
465 boolean buffered_image
; /* TRUE=multiple output passes */
466 boolean raw_data_out
; /* TRUE=downsampled data wanted */
468 J_DCT_METHOD dct_method
; /* IDCT algorithm selector */
469 boolean do_fancy_upsampling
; /* TRUE=apply fancy upsampling */
470 boolean do_block_smoothing
; /* TRUE=apply interblock smoothing */
472 boolean quantize_colors
; /* TRUE=colormapped output wanted */
473 /* the following are ignored if not quantize_colors: */
474 J_DITHER_MODE dither_mode
; /* type of color dithering to use */
475 boolean two_pass_quantize
; /* TRUE=use two-pass color quantization */
476 int desired_number_of_colors
; /* max # colors to use in created colormap */
477 /* these are significant only in buffered-image mode: */
478 boolean enable_1pass_quant
; /* enable future use of 1-pass quantizer */
479 boolean enable_external_quant
;/* enable future use of external colormap */
480 boolean enable_2pass_quant
; /* enable future use of 2-pass quantizer */
482 /* Description of actual output image that will be returned to application.
483 * These fields are computed by jpeg_start_decompress().
484 * You can also use jpeg_calc_output_dimensions() to determine these values
485 * in advance of calling jpeg_start_decompress().
488 JDIMENSION output_width
; /* scaled image width */
489 JDIMENSION output_height
; /* scaled image height */
490 int out_color_components
; /* # of color components in out_color_space */
491 int output_components
; /* # of color components returned */
492 /* output_components is 1 (a colormap index) when quantizing colors;
493 * otherwise it equals out_color_components.
495 int rec_outbuf_height
; /* min recommended height of scanline buffer */
496 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
497 * high, space and time will be wasted due to unnecessary data copying.
498 * Usually rec_outbuf_height will be 1 or 2, at most 4.
501 /* When quantizing colors, the output colormap is described by these fields.
502 * The application can supply a colormap by setting colormap non-NULL before
503 * calling jpeg_start_decompress; otherwise a colormap is created during
504 * jpeg_start_decompress or jpeg_start_output.
505 * The map has out_color_components rows and actual_number_of_colors columns.
507 int actual_number_of_colors
; /* number of entries in use */
508 JSAMPARRAY colormap
; /* The color map as a 2-D pixel array */
510 /* State variables: these variables indicate the progress of decompression.
511 * The application may examine these but must not modify them.
514 /* Row index of next scanline to be read from jpeg_read_scanlines().
515 * Application may use this to control its processing loop, e.g.,
516 * "while (output_scanline < output_height)".
518 JDIMENSION output_scanline
; /* 0 .. output_height-1 */
520 /* Current input scan number and number of iMCU rows completed in scan.
521 * These indicate the progress of the decompressor input side.
523 int input_scan_number
; /* Number of SOS markers seen so far */
524 JDIMENSION input_iMCU_row
; /* Number of iMCU rows completed */
526 /* The "output scan number" is the notional scan being displayed by the
527 * output side. The decompressor will not allow output scan/row number
528 * to get ahead of input scan/row, but it can fall arbitrarily far behind.
530 int output_scan_number
; /* Nominal scan number being displayed */
531 JDIMENSION output_iMCU_row
; /* Number of iMCU rows read */
533 /* Current progression status. coef_bits[c][i] indicates the precision
534 * with which component c's DCT coefficient i (in zigzag order) is known.
535 * It is -1 when no data has yet been received, otherwise it is the point
536 * transform (shift) value for the most recent scan of the coefficient
537 * (thus, 0 at completion of the progression).
538 * This pointer is NULL when reading a non-progressive file.
540 int (*coef_bits
)[DCTSIZE2
]; /* -1 or current Al value for each coef */
542 /* Internal JPEG parameters --- the application usually need not look at
543 * these fields. Note that the decompressor output side may not use
544 * any parameters that can change between scans.
547 /* Quantization and Huffman tables are carried forward across input
548 * datastreams when processing abbreviated JPEG datastreams.
551 JQUANT_TBL
* quant_tbl_ptrs
[NUM_QUANT_TBLS
];
552 /* ptrs to coefficient quantization tables, or NULL if not defined */
554 JHUFF_TBL
* dc_huff_tbl_ptrs
[NUM_HUFF_TBLS
];
555 JHUFF_TBL
* ac_huff_tbl_ptrs
[NUM_HUFF_TBLS
];
556 /* ptrs to Huffman coding tables, or NULL if not defined */
558 /* These parameters are never carried across datastreams, since they
559 * are given in SOF/SOS markers or defined to be reset by SOI.
562 int data_precision
; /* bits of precision in image data */
564 jpeg_component_info
* comp_info
;
565 /* comp_info[i] describes component that appears i'th in SOF */
567 boolean is_baseline
; /* TRUE if Baseline SOF0 encountered */
568 boolean progressive_mode
; /* TRUE if SOFn specifies progressive mode */
569 boolean arith_code
; /* TRUE=arithmetic coding, FALSE=Huffman */
571 UINT8 arith_dc_L
[NUM_ARITH_TBLS
]; /* L values for DC arith-coding tables */
572 UINT8 arith_dc_U
[NUM_ARITH_TBLS
]; /* U values for DC arith-coding tables */
573 UINT8 arith_ac_K
[NUM_ARITH_TBLS
]; /* Kx values for AC arith-coding tables */
575 unsigned int restart_interval
; /* MCUs per restart interval, or 0 for no restart */
577 /* These fields record data obtained from optional markers recognized by
580 boolean saw_JFIF_marker
; /* TRUE iff a JFIF APP0 marker was found */
581 /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */
582 UINT8 JFIF_major_version
; /* JFIF version number */
583 UINT8 JFIF_minor_version
;
584 UINT8 density_unit
; /* JFIF code for pixel size units */
585 UINT16 X_density
; /* Horizontal pixel density */
586 UINT16 Y_density
; /* Vertical pixel density */
587 boolean saw_Adobe_marker
; /* TRUE iff an Adobe APP14 marker was found */
588 UINT8 Adobe_transform
; /* Color transform code from Adobe marker */
590 boolean CCIR601_sampling
; /* TRUE=first samples are cosited */
592 /* Aside from the specific data retained from APPn markers known to the
593 * library, the uninterpreted contents of any or all APPn and COM markers
594 * can be saved in a list for examination by the application.
596 jpeg_saved_marker_ptr marker_list
; /* Head of list of saved markers */
598 /* Remaining fields are known throughout decompressor, but generally
599 * should not be touched by a surrounding application.
603 * These fields are computed during decompression startup
605 int max_h_samp_factor
; /* largest h_samp_factor */
606 int max_v_samp_factor
; /* largest v_samp_factor */
608 int min_DCT_h_scaled_size
; /* smallest DCT_h_scaled_size of any component */
609 int min_DCT_v_scaled_size
; /* smallest DCT_v_scaled_size of any component */
611 JDIMENSION total_iMCU_rows
; /* # of iMCU rows in image */
612 /* The coefficient controller's input and output progress is measured in
613 * units of "iMCU" (interleaved MCU) rows. These are the same as MCU rows
614 * in fully interleaved JPEG scans, but are used whether the scan is
615 * interleaved or not. We define an iMCU row as v_samp_factor DCT block
616 * rows of each component. Therefore, the IDCT output contains
617 * v_samp_factor*DCT_v_scaled_size sample rows of a component per iMCU row.
620 JSAMPLE
* sample_range_limit
; /* table for fast range-limiting */
623 * These fields are valid during any one scan.
624 * They describe the components and MCUs actually appearing in the scan.
625 * Note that the decompressor output side must not use these fields.
627 int comps_in_scan
; /* # of JPEG components in this scan */
628 jpeg_component_info
* cur_comp_info
[MAX_COMPS_IN_SCAN
];
629 /* *cur_comp_info[i] describes component that appears i'th in SOS */
631 JDIMENSION MCUs_per_row
; /* # of MCUs across the image */
632 JDIMENSION MCU_rows_in_scan
; /* # of MCU rows in the image */
634 int blocks_in_MCU
; /* # of DCT blocks per MCU */
635 int MCU_membership
[D_MAX_BLOCKS_IN_MCU
];
636 /* MCU_membership[i] is index in cur_comp_info of component owning */
637 /* i'th block in an MCU */
639 int Ss
, Se
, Ah
, Al
; /* progressive JPEG parameters for scan */
641 /* These fields are derived from Se of first SOS marker.
643 int block_size
; /* the basic DCT block size: 1..16 */
644 const int * natural_order
; /* natural-order position array for entropy decode */
645 int lim_Se
; /* min( Se, DCTSIZE2-1 ) for entropy decode */
647 /* This field is shared between entropy decoder and marker parser.
648 * It is either zero or the code of a JPEG marker that has been
649 * read from the data source, but has not yet been processed.
654 * Links to decompression subobjects (methods, private variables of modules)
656 struct jpeg_decomp_master
* master
;
657 struct jpeg_d_main_controller
* main
;
658 struct jpeg_d_coef_controller
* coef
;
659 struct jpeg_d_post_controller
* post
;
660 struct jpeg_input_controller
* inputctl
;
661 struct jpeg_marker_reader
* marker
;
662 struct jpeg_entropy_decoder
* entropy
;
663 struct jpeg_inverse_dct
* idct
;
664 struct jpeg_upsampler
* upsample
;
665 struct jpeg_color_deconverter
* cconvert
;
666 struct jpeg_color_quantizer
* cquantize
;
670 /* "Object" declarations for JPEG modules that may be supplied or called
671 * directly by the surrounding application.
672 * As with all objects in the JPEG library, these structs only define the
673 * publicly visible methods and state variables of a module. Additional
674 * private fields may exist after the public ones.
678 /* Error handler object */
680 struct jpeg_error_mgr
{
681 /* Error exit handler: does not return to caller */
682 JMETHOD(void, error_exit
, (j_common_ptr cinfo
));
683 /* Conditionally emit a trace or warning message */
684 JMETHOD(void, emit_message
, (j_common_ptr cinfo
, int msg_level
));
685 /* Routine that actually outputs a trace or error message */
686 JMETHOD(void, output_message
, (j_common_ptr cinfo
));
687 /* Format a message string for the most recent JPEG error or message */
688 JMETHOD(void, format_message
, (j_common_ptr cinfo
, char * buffer
));
689 #define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */
690 /* Reset error state variables at start of a new image */
691 JMETHOD(void, reset_error_mgr
, (j_common_ptr cinfo
));
693 /* The message ID code and any parameters are saved here.
694 * A message can have one string parameter or up to 8 int parameters.
697 #define JMSG_STR_PARM_MAX 80
700 char s
[JMSG_STR_PARM_MAX
];
703 /* Standard state variables for error facility */
705 int trace_level
; /* max msg_level that will be displayed */
707 /* For recoverable corrupt-data errors, we emit a warning message,
708 * but keep going unless emit_message chooses to abort. emit_message
709 * should count warnings in num_warnings. The surrounding application
710 * can check for bad data by seeing if num_warnings is nonzero at the
713 long num_warnings
; /* number of corrupt-data warnings */
715 /* These fields point to the table(s) of error message strings.
716 * An application can change the table pointer to switch to a different
717 * message list (typically, to change the language in which errors are
718 * reported). Some applications may wish to add additional error codes
719 * that will be handled by the JPEG library error mechanism; the second
720 * table pointer is used for this purpose.
722 * First table includes all errors generated by JPEG library itself.
723 * Error code 0 is reserved for a "no such error string" message.
725 const char * const * jpeg_message_table
; /* Library errors */
726 int last_jpeg_message
; /* Table contains strings 0..last_jpeg_message */
727 /* Second table can be added by application (see cjpeg/djpeg for example).
728 * It contains strings numbered first_addon_message..last_addon_message.
730 const char * const * addon_message_table
; /* Non-library errors */
731 int first_addon_message
; /* code for first string in addon table */
732 int last_addon_message
; /* code for last string in addon table */
736 /* Progress monitor object */
738 struct jpeg_progress_mgr
{
739 JMETHOD(void, progress_monitor
, (j_common_ptr cinfo
));
741 long pass_counter
; /* work units completed in this pass */
742 long pass_limit
; /* total number of work units in this pass */
743 int completed_passes
; /* passes completed so far */
744 int total_passes
; /* total number of passes expected */
748 /* Data destination object for compression */
750 struct jpeg_destination_mgr
{
751 JOCTET
* next_output_byte
; /* => next byte to write in buffer */
752 size_t free_in_buffer
; /* # of byte spaces remaining in buffer */
754 JMETHOD(void, init_destination
, (j_compress_ptr cinfo
));
755 JMETHOD(boolean
, empty_output_buffer
, (j_compress_ptr cinfo
));
756 JMETHOD(void, term_destination
, (j_compress_ptr cinfo
));
760 /* Data source object for decompression */
762 struct jpeg_source_mgr
{
763 const JOCTET
* next_input_byte
; /* => next byte to read from buffer */
764 size_t bytes_in_buffer
; /* # of bytes remaining in buffer */
766 JMETHOD(void, init_source
, (j_decompress_ptr cinfo
));
767 JMETHOD(boolean
, fill_input_buffer
, (j_decompress_ptr cinfo
));
768 JMETHOD(void, skip_input_data
, (j_decompress_ptr cinfo
, long num_bytes
));
769 JMETHOD(boolean
, resync_to_restart
, (j_decompress_ptr cinfo
, int desired
));
770 JMETHOD(void, term_source
, (j_decompress_ptr cinfo
));
774 /* Memory manager object.
775 * Allocates "small" objects (a few K total), "large" objects (tens of K),
776 * and "really big" objects (virtual arrays with backing store if needed).
777 * The memory manager does not allow individual objects to be freed; rather,
778 * each created object is assigned to a pool, and whole pools can be freed
779 * at once. This is faster and more convenient than remembering exactly what
780 * to free, especially where malloc()/free() are not too speedy.
781 * NB: alloc routines never return NULL. They exit to error_exit if not
785 #define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */
786 #define JPOOL_IMAGE 1 /* lasts until done with image/datastream */
787 #define JPOOL_NUMPOOLS 2
789 typedef struct jvirt_sarray_control
* jvirt_sarray_ptr
;
790 typedef struct jvirt_barray_control
* jvirt_barray_ptr
;
793 struct jpeg_memory_mgr
{
794 /* Method pointers */
795 JMETHOD(void *, alloc_small
, (j_common_ptr cinfo
, int pool_id
,
796 size_t sizeofobject
));
797 JMETHOD(void FAR
*, alloc_large
, (j_common_ptr cinfo
, int pool_id
,
798 size_t sizeofobject
));
799 JMETHOD(JSAMPARRAY
, alloc_sarray
, (j_common_ptr cinfo
, int pool_id
,
800 JDIMENSION samplesperrow
,
801 JDIMENSION numrows
));
802 JMETHOD(JBLOCKARRAY
, alloc_barray
, (j_common_ptr cinfo
, int pool_id
,
803 JDIMENSION blocksperrow
,
804 JDIMENSION numrows
));
805 JMETHOD(jvirt_sarray_ptr
, request_virt_sarray
, (j_common_ptr cinfo
,
808 JDIMENSION samplesperrow
,
810 JDIMENSION maxaccess
));
811 JMETHOD(jvirt_barray_ptr
, request_virt_barray
, (j_common_ptr cinfo
,
814 JDIMENSION blocksperrow
,
816 JDIMENSION maxaccess
));
817 JMETHOD(void, realize_virt_arrays
, (j_common_ptr cinfo
));
818 JMETHOD(JSAMPARRAY
, access_virt_sarray
, (j_common_ptr cinfo
,
819 jvirt_sarray_ptr ptr
,
820 JDIMENSION start_row
,
823 JMETHOD(JBLOCKARRAY
, access_virt_barray
, (j_common_ptr cinfo
,
824 jvirt_barray_ptr ptr
,
825 JDIMENSION start_row
,
828 JMETHOD(void, free_pool
, (j_common_ptr cinfo
, int pool_id
));
829 JMETHOD(void, self_destruct
, (j_common_ptr cinfo
));
831 /* Limit on memory allocation for this JPEG object. (Note that this is
832 * merely advisory, not a guaranteed maximum; it only affects the space
833 * used for virtual-array buffers.) May be changed by outer application
834 * after creating the JPEG object.
836 long max_memory_to_use
;
838 /* Maximum allocation request accepted by alloc_large. */
839 long max_alloc_chunk
;
843 /* Routine signature for application-supplied marker processing methods.
844 * Need not pass marker code since it is stored in cinfo->unread_marker.
846 typedef JMETHOD(boolean
, jpeg_marker_parser_method
, (j_decompress_ptr cinfo
));
849 /* Declarations for routines called by application.
850 * The JPP macro hides prototype parameters from compilers that can't cope.
851 * Note JPP requires double parentheses.
854 #ifdef HAVE_PROTOTYPES
855 #define JPP(arglist) arglist
857 #define JPP(arglist) ()
861 /* Short forms of external names for systems with brain-damaged linkers.
862 * We shorten external names to be unique in the first six letters, which
863 * is good enough for all known systems.
864 * (If your compiler itself needs names to be unique in less than 15
865 * characters, you are out of luck. Get a better compiler.)
868 #ifdef NEED_SHORT_EXTERNAL_NAMES
869 #define jpeg_std_error jStdError
870 #define jpeg_CreateCompress jCreaCompress
871 #define jpeg_CreateDecompress jCreaDecompress
872 #define jpeg_destroy_compress jDestCompress
873 #define jpeg_destroy_decompress jDestDecompress
874 #define jpeg_stdio_dest jStdDest
875 #define jpeg_stdio_src jStdSrc
876 #define jpeg_mem_dest jMemDest
877 #define jpeg_mem_src jMemSrc
878 #define jpeg_set_defaults jSetDefaults
879 #define jpeg_set_colorspace jSetColorspace
880 #define jpeg_default_colorspace jDefColorspace
881 #define jpeg_set_quality jSetQuality
882 #define jpeg_set_linear_quality jSetLQuality
883 #define jpeg_default_qtables jDefQTables
884 #define jpeg_add_quant_table jAddQuantTable
885 #define jpeg_quality_scaling jQualityScaling
886 #define jpeg_simple_progression jSimProgress
887 #define jpeg_suppress_tables jSuppressTables
888 #define jpeg_alloc_quant_table jAlcQTable
889 #define jpeg_alloc_huff_table jAlcHTable
890 #define jpeg_start_compress jStrtCompress
891 #define jpeg_write_scanlines jWrtScanlines
892 #define jpeg_finish_compress jFinCompress
893 #define jpeg_calc_jpeg_dimensions jCjpegDimensions
894 #define jpeg_write_raw_data jWrtRawData
895 #define jpeg_write_marker jWrtMarker
896 #define jpeg_write_m_header jWrtMHeader
897 #define jpeg_write_m_byte jWrtMByte
898 #define jpeg_write_tables jWrtTables
899 #define jpeg_read_header jReadHeader
900 #define jpeg_start_decompress jStrtDecompress
901 #define jpeg_read_scanlines jReadScanlines
902 #define jpeg_finish_decompress jFinDecompress
903 #define jpeg_read_raw_data jReadRawData
904 #define jpeg_has_multiple_scans jHasMultScn
905 #define jpeg_start_output jStrtOutput
906 #define jpeg_finish_output jFinOutput
907 #define jpeg_input_complete jInComplete
908 #define jpeg_new_colormap jNewCMap
909 #define jpeg_consume_input jConsumeInput
910 #define jpeg_core_output_dimensions jCoreDimensions
911 #define jpeg_calc_output_dimensions jCalcDimensions
912 #define jpeg_save_markers jSaveMarkers
913 #define jpeg_set_marker_processor jSetMarker
914 #define jpeg_read_coefficients jReadCoefs
915 #define jpeg_write_coefficients jWrtCoefs
916 #define jpeg_copy_critical_parameters jCopyCrit
917 #define jpeg_abort_compress jAbrtCompress
918 #define jpeg_abort_decompress jAbrtDecompress
919 #define jpeg_abort jAbort
920 #define jpeg_destroy jDestroy
921 #define jpeg_resync_to_restart jResyncRestart
922 #endif /* NEED_SHORT_EXTERNAL_NAMES */
925 /* Default error-management setup */
926 EXTERN(struct jpeg_error_mgr
*) jpeg_std_error
927 JPP((struct jpeg_error_mgr
* err
));
929 /* Initialization of JPEG compression objects.
930 * jpeg_create_compress() and jpeg_create_decompress() are the exported
931 * names that applications should call. These expand to calls on
932 * jpeg_CreateCompress and jpeg_CreateDecompress with additional information
933 * passed for version mismatch checking.
934 * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx.
936 #define jpeg_create_compress(cinfo) \
937 jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \
938 (size_t) sizeof(struct jpeg_compress_struct))
939 #define jpeg_create_decompress(cinfo) \
940 jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \
941 (size_t) sizeof(struct jpeg_decompress_struct))
942 EXTERN(void) jpeg_CreateCompress
JPP((j_compress_ptr cinfo
,
943 int version
, size_t structsize
));
944 EXTERN(void) jpeg_CreateDecompress
JPP((j_decompress_ptr cinfo
,
945 int version
, size_t structsize
));
946 /* Destruction of JPEG compression objects */
947 EXTERN(void) jpeg_destroy_compress
JPP((j_compress_ptr cinfo
));
948 EXTERN(void) jpeg_destroy_decompress
JPP((j_decompress_ptr cinfo
));
950 /* Standard data source and destination managers: stdio streams. */
951 /* Caller is responsible for opening the file before and closing after. */
952 EXTERN(void) jpeg_stdio_dest
JPP((j_compress_ptr cinfo
, FILE * outfile
));
953 EXTERN(void) jpeg_stdio_src
JPP((j_decompress_ptr cinfo
, FILE * infile
));
955 /* Data source and destination managers: memory buffers. */
956 EXTERN(void) jpeg_mem_dest
JPP((j_compress_ptr cinfo
,
957 unsigned char ** outbuffer
,
958 unsigned long * outsize
));
959 EXTERN(void) jpeg_mem_src
JPP((j_decompress_ptr cinfo
,
960 unsigned char * inbuffer
,
961 unsigned long insize
));
963 /* Default parameter setup for compression */
964 EXTERN(void) jpeg_set_defaults
JPP((j_compress_ptr cinfo
));
965 /* Compression parameter setup aids */
966 EXTERN(void) jpeg_set_colorspace
JPP((j_compress_ptr cinfo
,
967 J_COLOR_SPACE colorspace
));
968 EXTERN(void) jpeg_default_colorspace
JPP((j_compress_ptr cinfo
));
969 EXTERN(void) jpeg_set_quality
JPP((j_compress_ptr cinfo
, int quality
,
970 boolean force_baseline
));
971 EXTERN(void) jpeg_set_linear_quality
JPP((j_compress_ptr cinfo
,
973 boolean force_baseline
));
974 EXTERN(void) jpeg_default_qtables
JPP((j_compress_ptr cinfo
,
975 boolean force_baseline
));
976 EXTERN(void) jpeg_add_quant_table
JPP((j_compress_ptr cinfo
, int which_tbl
,
977 const unsigned int *basic_table
,
979 boolean force_baseline
));
980 EXTERN(int) jpeg_quality_scaling
JPP((int quality
));
981 EXTERN(void) jpeg_simple_progression
JPP((j_compress_ptr cinfo
));
982 EXTERN(void) jpeg_suppress_tables
JPP((j_compress_ptr cinfo
,
984 EXTERN(JQUANT_TBL
*) jpeg_alloc_quant_table
JPP((j_common_ptr cinfo
));
985 EXTERN(JHUFF_TBL
*) jpeg_alloc_huff_table
JPP((j_common_ptr cinfo
));
987 /* Main entry points for compression */
988 EXTERN(void) jpeg_start_compress
JPP((j_compress_ptr cinfo
,
989 boolean write_all_tables
));
990 EXTERN(JDIMENSION
) jpeg_write_scanlines
JPP((j_compress_ptr cinfo
,
991 JSAMPARRAY scanlines
,
992 JDIMENSION num_lines
));
993 EXTERN(void) jpeg_finish_compress
JPP((j_compress_ptr cinfo
));
995 /* Precalculate JPEG dimensions for current compression parameters. */
996 EXTERN(void) jpeg_calc_jpeg_dimensions
JPP((j_compress_ptr cinfo
));
998 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
999 EXTERN(JDIMENSION
) jpeg_write_raw_data
JPP((j_compress_ptr cinfo
,
1001 JDIMENSION num_lines
));
1003 /* Write a special marker. See libjpeg.txt concerning safe usage. */
1004 EXTERN(void) jpeg_write_marker
1005 JPP((j_compress_ptr cinfo
, int marker
,
1006 const JOCTET
* dataptr
, unsigned int datalen
));
1007 /* Same, but piecemeal. */
1008 EXTERN(void) jpeg_write_m_header
1009 JPP((j_compress_ptr cinfo
, int marker
, unsigned int datalen
));
1010 EXTERN(void) jpeg_write_m_byte
1011 JPP((j_compress_ptr cinfo
, int val
));
1013 /* Alternate compression function: just write an abbreviated table file */
1014 EXTERN(void) jpeg_write_tables
JPP((j_compress_ptr cinfo
));
1016 /* Decompression startup: read start of JPEG datastream to see what's there */
1017 EXTERN(int) jpeg_read_header
JPP((j_decompress_ptr cinfo
,
1018 boolean require_image
));
1019 /* Return value is one of: */
1020 #define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */
1021 #define JPEG_HEADER_OK 1 /* Found valid image datastream */
1022 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */
1023 /* If you pass require_image = TRUE (normal case), you need not check for
1024 * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
1025 * JPEG_SUSPENDED is only possible if you use a data source module that can
1026 * give a suspension return (the stdio source module doesn't).
1029 /* Main entry points for decompression */
1030 EXTERN(boolean
) jpeg_start_decompress
JPP((j_decompress_ptr cinfo
));
1031 EXTERN(JDIMENSION
) jpeg_read_scanlines
JPP((j_decompress_ptr cinfo
,
1032 JSAMPARRAY scanlines
,
1033 JDIMENSION max_lines
));
1034 EXTERN(boolean
) jpeg_finish_decompress
JPP((j_decompress_ptr cinfo
));
1036 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
1037 EXTERN(JDIMENSION
) jpeg_read_raw_data
JPP((j_decompress_ptr cinfo
,
1039 JDIMENSION max_lines
));
1041 /* Additional entry points for buffered-image mode. */
1042 EXTERN(boolean
) jpeg_has_multiple_scans
JPP((j_decompress_ptr cinfo
));
1043 EXTERN(boolean
) jpeg_start_output
JPP((j_decompress_ptr cinfo
,
1045 EXTERN(boolean
) jpeg_finish_output
JPP((j_decompress_ptr cinfo
));
1046 EXTERN(boolean
) jpeg_input_complete
JPP((j_decompress_ptr cinfo
));
1047 EXTERN(void) jpeg_new_colormap
JPP((j_decompress_ptr cinfo
));
1048 EXTERN(int) jpeg_consume_input
JPP((j_decompress_ptr cinfo
));
1049 /* Return value is one of: */
1050 /* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */
1051 #define JPEG_REACHED_SOS 1 /* Reached start of new scan */
1052 #define JPEG_REACHED_EOI 2 /* Reached end of image */
1053 #define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */
1054 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */
1056 /* Precalculate output dimensions for current decompression parameters. */
1057 EXTERN(void) jpeg_core_output_dimensions
JPP((j_decompress_ptr cinfo
));
1058 EXTERN(void) jpeg_calc_output_dimensions
JPP((j_decompress_ptr cinfo
));
1060 /* Control saving of COM and APPn markers into marker_list. */
1061 EXTERN(void) jpeg_save_markers
1062 JPP((j_decompress_ptr cinfo
, int marker_code
,
1063 unsigned int length_limit
));
1065 /* Install a special processing method for COM or APPn markers. */
1066 EXTERN(void) jpeg_set_marker_processor
1067 JPP((j_decompress_ptr cinfo
, int marker_code
,
1068 jpeg_marker_parser_method routine
));
1070 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */
1071 EXTERN(jvirt_barray_ptr
*) jpeg_read_coefficients
JPP((j_decompress_ptr cinfo
));
1072 EXTERN(void) jpeg_write_coefficients
JPP((j_compress_ptr cinfo
,
1073 jvirt_barray_ptr
* coef_arrays
));
1074 EXTERN(void) jpeg_copy_critical_parameters
JPP((j_decompress_ptr srcinfo
,
1075 j_compress_ptr dstinfo
));
1077 /* If you choose to abort compression or decompression before completing
1078 * jpeg_finish_(de)compress, then you need to clean up to release memory,
1079 * temporary files, etc. You can just call jpeg_destroy_(de)compress
1080 * if you're done with the JPEG object, but if you want to clean it up and
1081 * reuse it, call this:
1083 EXTERN(void) jpeg_abort_compress
JPP((j_compress_ptr cinfo
));
1084 EXTERN(void) jpeg_abort_decompress
JPP((j_decompress_ptr cinfo
));
1086 /* Generic versions of jpeg_abort and jpeg_destroy that work on either
1087 * flavor of JPEG object. These may be more convenient in some places.
1089 EXTERN(void) jpeg_abort
JPP((j_common_ptr cinfo
));
1090 EXTERN(void) jpeg_destroy
JPP((j_common_ptr cinfo
));
1092 /* Default restart-marker-resync procedure for use by data source modules */
1093 EXTERN(boolean
) jpeg_resync_to_restart
JPP((j_decompress_ptr cinfo
,
1097 /* These marker codes are exported since applications and data source modules
1098 * are likely to want to use them.
1101 #define JPEG_RST0 0xD0 /* RST0 marker code */
1102 #define JPEG_EOI 0xD9 /* EOI marker code */
1103 #define JPEG_APP0 0xE0 /* APP0 marker code */
1104 #define JPEG_COM 0xFE /* COM marker code */
1107 /* If we have a brain-damaged compiler that emits warnings (or worse, errors)
1108 * for structure definitions that are never filled in, keep it quiet by
1109 * supplying dummy definitions for the various substructures.
1112 #ifdef INCOMPLETE_TYPES_BROKEN
1113 #ifndef JPEG_INTERNALS /* will be defined in jpegint.h */
1114 struct jvirt_sarray_control
{ long dummy
; };
1115 struct jvirt_barray_control
{ long dummy
; };
1116 struct jpeg_comp_master
{ long dummy
; };
1117 struct jpeg_c_main_controller
{ long dummy
; };
1118 struct jpeg_c_prep_controller
{ long dummy
; };
1119 struct jpeg_c_coef_controller
{ long dummy
; };
1120 struct jpeg_marker_writer
{ long dummy
; };
1121 struct jpeg_color_converter
{ long dummy
; };
1122 struct jpeg_downsampler
{ long dummy
; };
1123 struct jpeg_forward_dct
{ long dummy
; };
1124 struct jpeg_entropy_encoder
{ long dummy
; };
1125 struct jpeg_decomp_master
{ long dummy
; };
1126 struct jpeg_d_main_controller
{ long dummy
; };
1127 struct jpeg_d_coef_controller
{ long dummy
; };
1128 struct jpeg_d_post_controller
{ long dummy
; };
1129 struct jpeg_input_controller
{ long dummy
; };
1130 struct jpeg_marker_reader
{ long dummy
; };
1131 struct jpeg_entropy_decoder
{ long dummy
; };
1132 struct jpeg_inverse_dct
{ long dummy
; };
1133 struct jpeg_upsampler
{ long dummy
; };
1134 struct jpeg_color_deconverter
{ long dummy
; };
1135 struct jpeg_color_quantizer
{ long dummy
; };
1136 #endif /* JPEG_INTERNALS */
1137 #endif /* INCOMPLETE_TYPES_BROKEN */
1141 * The JPEG library modules define JPEG_INTERNALS before including this file.
1142 * The internal structure declarations are read only when that is true.
1143 * Applications using the library should not include jpegint.h, but may wish
1144 * to include jerror.h.
1147 #ifdef JPEG_INTERNALS
1148 #include "jpegint.h" /* fetch private declarations */
1149 #include "jerror.h" /* fetch error codes too */
1153 #ifndef DONT_USE_EXTERN_C
1158 #endif /* JPEGLIB_H */