4 * This file was part of the Independent JPEG Group's software:
5 * Copyright (C) 1991-1998, Thomas G. Lane.
6 * Modified 2002-2009 by Guido Vollbeding.
7 * libjpeg-turbo Modifications:
8 * Copyright (C) 2009-2011, 2013-2014, 2016-2017, 2020, D. R. Commander.
9 * Copyright (C) 2015, Google, Inc.
10 * For conditions of distribution and use, see the accompanying README.ijg
13 * This file defines the application interface for the JPEG library.
14 * Most applications using the library need only include this file,
15 * and perhaps jerror.h if they want to know the exact error codes.
22 * First we include the configuration files that record how this
23 * installation of the JPEG library is set up. jconfig.h can be
24 * generated automatically for many systems. jmorecfg.h contains
25 * manual configuration options that most people need not worry about.
28 #ifndef JCONFIG_INCLUDED /* in case jinclude.h already did */
29 #include "jconfig.h" /* widely used configuration options */
31 #include "jmorecfg.h" /* seldom changed options */
35 #ifndef DONT_USE_EXTERN_C
40 /* Various constants determining the sizes of things.
41 * All of these are specified by the JPEG standard, so don't change them
42 * if you want to be compatible.
45 #define DCTSIZE 8 /* The basic DCT block is 8x8 samples */
46 #define DCTSIZE2 64 /* DCTSIZE squared; # of elements in a block */
47 #define NUM_QUANT_TBLS 4 /* Quantization tables are numbered 0..3 */
48 #define NUM_HUFF_TBLS 4 /* Huffman tables are numbered 0..3 */
49 #define NUM_ARITH_TBLS 16 /* Arith-coding tables are numbered 0..15 */
50 #define MAX_COMPS_IN_SCAN 4 /* JPEG limit on # of components in one scan */
51 #define MAX_SAMP_FACTOR 4 /* JPEG limit on sampling factors */
52 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
53 * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
54 * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
55 * to handle it. We even let you do this from the jconfig.h file. However,
56 * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
57 * sometimes emits noncompliant files doesn't mean you should too.
59 #define C_MAX_BLOCKS_IN_MCU 10 /* compressor's limit on blocks per MCU */
60 #ifndef D_MAX_BLOCKS_IN_MCU
61 #define D_MAX_BLOCKS_IN_MCU 10 /* decompressor's limit on blocks per MCU */
65 /* Data structures for images (arrays of samples and of DCT coefficients).
68 typedef JSAMPLE *JSAMPROW; /* ptr to one image row of pixel samples. */
69 typedef JSAMPROW *JSAMPARRAY; /* ptr to some rows (a 2-D sample array) */
70 typedef JSAMPARRAY *JSAMPIMAGE; /* a 3-D sample array: top index is color */
72 typedef JCOEF JBLOCK[DCTSIZE2]; /* one block of coefficients */
73 typedef JBLOCK *JBLOCKROW; /* pointer to one row of coefficient blocks */
74 typedef JBLOCKROW *JBLOCKARRAY; /* a 2-D array of coefficient blocks */
75 typedef JBLOCKARRAY *JBLOCKIMAGE; /* a 3-D array of coefficient blocks */
77 typedef JCOEF *JCOEFPTR; /* useful in a couple of places */
80 /* Types for JPEG compression parameters and working tables. */
83 /* DCT coefficient quantization tables. */
86 /* This array gives the coefficient quantizers in natural array order
87 * (not the zigzag order in which they are stored in a JPEG DQT marker).
88 * CAUTION: IJG versions prior to v6a kept this array in zigzag order.
90 UINT16 quantval[DCTSIZE2]; /* quantization step for each coefficient */
91 /* This field is used only during compression. It's initialized FALSE when
92 * the table is created, and set TRUE when it's been output to the file.
93 * You could suppress output of a table by setting this to TRUE.
94 * (See jpeg_suppress_tables for an example.)
96 boolean sent_table; /* TRUE when table has been output */
100 /* Huffman coding tables. */
103 /* These two fields directly represent the contents of a JPEG DHT marker */
104 UINT8 bits[17]; /* bits[k] = # of symbols with codes of */
105 /* length k bits; bits[0] is unused */
106 UINT8 huffval[256]; /* The symbols, in order of incr code length */
107 /* This field is used only during compression. It's initialized FALSE when
108 * the table is created, and set TRUE when it's been output to the file.
109 * You could suppress output of a table by setting this to TRUE.
110 * (See jpeg_suppress_tables for an example.)
112 boolean sent_table; /* TRUE when table has been output */
116 /* Basic info about one component (color channel). */
119 /* These values are fixed over the whole image. */
120 /* For compression, they must be supplied by parameter setup; */
121 /* for decompression, they are read from the SOF marker. */
122 int component_id; /* identifier for this component (0..255) */
123 int component_index; /* its index in SOF or cinfo->comp_info[] */
124 int h_samp_factor; /* horizontal sampling factor (1..4) */
125 int v_samp_factor; /* vertical sampling factor (1..4) */
126 int quant_tbl_no; /* quantization table selector (0..3) */
127 /* These values may vary between scans. */
128 /* For compression, they must be supplied by parameter setup; */
129 /* for decompression, they are read from the SOS marker. */
130 /* The decompressor output side may not use these variables. */
131 int dc_tbl_no; /* DC entropy table selector (0..3) */
132 int ac_tbl_no; /* AC entropy table selector (0..3) */
134 /* Remaining fields should be treated as private by applications. */
136 /* These values are computed during compression or decompression startup: */
137 /* Component's size in DCT blocks.
138 * Any dummy blocks added to complete an MCU are not counted; therefore
139 * these values do not depend on whether a scan is interleaved or not.
141 JDIMENSION width_in_blocks;
142 JDIMENSION height_in_blocks;
143 /* Size of a DCT block in samples. Always DCTSIZE for compression.
144 * For decompression this is the size of the output from one DCT block,
145 * reflecting any scaling we choose to apply during the IDCT step.
146 * Values from 1 to 16 are supported.
147 * Note that different components may receive different IDCT scalings.
149 #if JPEG_LIB_VERSION >= 70
150 int DCT_h_scaled_size;
151 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), thus
157 * downsampled_width = ceil(image_width * Hi/Hmax)
158 * and similarly for height. For decompression, IDCT scaling is included, so
159 * downsampled_width = ceil(image_width * Hi/Hmax * DCT_[h_]scaled_size/DCTSIZE)
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 *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 *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. */
213 #define JCS_EXTENSIONS 1
214 #define JCS_ALPHA_EXTENSIONS 1
217 JCS_UNKNOWN, /* error/unspecified */
218 JCS_GRAYSCALE, /* monochrome */
219 JCS_RGB, /* red/green/blue as specified by the RGB_RED,
220 RGB_GREEN, RGB_BLUE, and RGB_PIXELSIZE macros */
221 JCS_YCbCr, /* Y/Cb/Cr (also known as YUV) */
222 JCS_CMYK, /* C/M/Y/K */
223 JCS_YCCK, /* Y/Cb/Cr/K */
224 JCS_EXT_RGB, /* red/green/blue */
225 JCS_EXT_RGBX, /* red/green/blue/x */
226 JCS_EXT_BGR, /* blue/green/red */
227 JCS_EXT_BGRX, /* blue/green/red/x */
228 JCS_EXT_XBGR, /* x/blue/green/red */
229 JCS_EXT_XRGB, /* x/red/green/blue */
230 /* When out_color_space it set to JCS_EXT_RGBX, JCS_EXT_BGRX, JCS_EXT_XBGR,
231 or JCS_EXT_XRGB during decompression, the X byte is undefined, and in
232 order to ensure the best performance, libjpeg-turbo can set that byte to
233 whatever value it wishes. Use the following colorspace constants to
234 ensure that the X byte is set to 0xFF, so that it can be interpreted as an
235 opaque alpha channel. */
236 JCS_EXT_RGBA, /* red/green/blue/alpha */
237 JCS_EXT_BGRA, /* blue/green/red/alpha */
238 JCS_EXT_ABGR, /* alpha/blue/green/red */
239 JCS_EXT_ARGB, /* alpha/red/green/blue */
240 JCS_RGB565 /* 5-bit red/6-bit green/5-bit blue */
243 /* DCT/IDCT algorithm options. */
246 JDCT_ISLOW, /* accurate integer method */
247 JDCT_IFAST, /* less accurate integer method [legacy feature] */
248 JDCT_FLOAT /* floating-point method [legacy feature] */
251 #ifndef JDCT_DEFAULT /* may be overridden in jconfig.h */
252 #define JDCT_DEFAULT JDCT_ISLOW
254 #ifndef JDCT_FASTEST /* may be overridden in jconfig.h */
255 #define JDCT_FASTEST JDCT_IFAST
258 /* Dithering options for decompression. */
261 JDITHER_NONE, /* no dithering */
262 JDITHER_ORDERED, /* simple ordered dither */
263 JDITHER_FS /* Floyd-Steinberg error diffusion dither */
267 /* Common fields between JPEG compression and decompression master structs. */
269 #define jpeg_common_fields \
270 struct jpeg_error_mgr *err; /* Error handler module */ \
271 struct jpeg_memory_mgr *mem; /* Memory manager module */ \
272 struct jpeg_progress_mgr *progress; /* Progress monitor, or NULL if none */ \
273 void *client_data; /* Available for use by application */ \
274 boolean is_decompressor; /* So common code can tell which is which */ \
275 int global_state /* For checking call sequence validity */
277 /* Routines that are to be used by both halves of the library are declared
278 * to receive a pointer to this structure. There are no actual instances of
279 * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
281 struct jpeg_common_struct {
282 jpeg_common_fields; /* Fields common to both master struct types */
283 /* Additional fields follow in an actual jpeg_compress_struct or
284 * jpeg_decompress_struct. All three structs must agree on these
285 * initial fields! (This would be a lot cleaner in C++.)
289 typedef struct jpeg_common_struct *j_common_ptr;
290 typedef struct jpeg_compress_struct *j_compress_ptr;
291 typedef struct jpeg_decompress_struct *j_decompress_ptr;
293 typedef struct _Pick_Color_
306 /* Master record for a compression instance */
308 struct jpeg_compress_struct {
309 jpeg_common_fields; /* Fields shared with jpeg_decompress_struct */
311 /* Destination for compressed data */
312 struct jpeg_destination_mgr *dest;
314 /* Description of source image --- these fields must be filled in by
315 * outer application before starting compression. in_color_space must
316 * be correct before you can even call jpeg_set_defaults().
319 JDIMENSION image_width; /* input image width */
320 JDIMENSION image_height; /* input image height */
321 int input_components; /* # of color components in input image */
322 J_COLOR_SPACE in_color_space; /* colorspace of input image */
324 double input_gamma; /* image gamma of input image */
326 /* Compression parameters --- these fields must be set before calling
327 * jpeg_start_compress(). We recommend calling jpeg_set_defaults() to
328 * initialize everything to reasonable defaults, then changing anything
329 * the application specifically wants to change. That way you won't get
330 * burnt when new parameters are added. Also note that there are several
331 * helper routines to simplify changing parameters.
334 #if JPEG_LIB_VERSION >= 70
335 unsigned int scale_num, scale_denom; /* fraction by which to scale image */
337 JDIMENSION jpeg_width; /* scaled JPEG image width */
338 JDIMENSION jpeg_height; /* scaled JPEG image height */
339 /* Dimensions of actual JPEG image that will be written to file,
340 * derived from input dimensions by scaling factors above.
341 * These fields are computed by jpeg_start_compress().
342 * You can also use jpeg_calc_jpeg_dimensions() to determine these values
343 * in advance of calling jpeg_start_compress().
347 int data_precision; /* bits of precision in image data */
349 int num_components; /* # of color components in JPEG image */
350 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
352 jpeg_component_info *comp_info;
353 /* comp_info[i] describes component that appears i'th in SOF */
355 JQUANT_TBL *quant_tbl_ptrs[NUM_QUANT_TBLS];
356 #if JPEG_LIB_VERSION >= 70
357 int q_scale_factor[NUM_QUANT_TBLS];
359 /* ptrs to coefficient quantization tables, or NULL if not defined,
360 * and corresponding scale factors (percentage, initialized 100).
363 JHUFF_TBL *dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
364 JHUFF_TBL *ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
365 /* ptrs to Huffman coding tables, or NULL if not defined */
367 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
368 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
369 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
371 int num_scans; /* # of entries in scan_info array */
372 const jpeg_scan_info *scan_info; /* script for multi-scan file, or NULL */
373 /* The default value of scan_info is NULL, which causes a single-scan
374 * sequential JPEG file to be emitted. To create a multi-scan file,
375 * set num_scans and scan_info to point to an array of scan definitions.
378 boolean raw_data_in; /* TRUE=caller supplies downsampled data */
379 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
380 boolean optimize_coding; /* TRUE=optimize entropy encoding parms */
381 boolean CCIR601_sampling; /* TRUE=first samples are cosited */
382 #if JPEG_LIB_VERSION >= 70
383 boolean do_fancy_downsampling; /* TRUE=apply fancy downsampling */
385 int smoothing_factor; /* 1..100, or 0 for no input smoothing */
386 J_DCT_METHOD dct_method; /* DCT algorithm selector */
388 /* The restart interval can be specified in absolute MCUs by setting
389 * restart_interval, or in MCU rows by setting restart_in_rows
390 * (in which case the correct restart_interval will be figured
393 unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
394 int restart_in_rows; /* if > 0, MCU rows per restart interval */
396 /* Parameters controlling emission of special markers. */
398 boolean write_JFIF_header; /* should a JFIF marker be written? */
399 UINT8 JFIF_major_version; /* What to write for the JFIF version number */
400 UINT8 JFIF_minor_version;
401 /* These three values are not used by the JPEG code, merely copied */
402 /* into the JFIF APP0 marker. density_unit can be 0 for unknown, */
403 /* 1 for dots/inch, or 2 for dots/cm. Note that the pixel aspect */
404 /* ratio is defined by X_density/Y_density even when density_unit=0. */
405 UINT8 density_unit; /* JFIF code for pixel size units */
406 UINT16 X_density; /* Horizontal pixel density */
407 UINT16 Y_density; /* Vertical pixel density */
408 boolean write_Adobe_marker; /* should an Adobe marker be written? */
410 /* State variable: index of next scanline to be written to
411 * jpeg_write_scanlines(). Application may use this to control its
412 * processing loop, e.g., "while (next_scanline < image_height)".
415 JDIMENSION next_scanline; /* 0 .. image_height-1 */
417 /* Remaining fields are known throughout compressor, but generally
418 * should not be touched by a surrounding application.
422 * These fields are computed during compression startup
424 boolean progressive_mode; /* TRUE if scan script uses progressive mode */
425 int max_h_samp_factor; /* largest h_samp_factor */
426 int max_v_samp_factor; /* largest v_samp_factor */
428 #if JPEG_LIB_VERSION >= 70
429 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */
430 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */
433 JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coef ctlr */
434 /* The coefficient controller receives data in units of MCU rows as defined
435 * for fully interleaved scans (whether the JPEG file is interleaved or not).
436 * There are v_samp_factor * DCTSIZE sample rows of each component in an
437 * "iMCU" (interleaved MCU) row.
441 * These fields are valid during any one scan.
442 * They describe the components and MCUs actually appearing in the scan.
444 int comps_in_scan; /* # of JPEG components in this scan */
445 jpeg_component_info *cur_comp_info[MAX_COMPS_IN_SCAN];
446 /* *cur_comp_info[i] describes component that appears i'th in SOS */
448 JDIMENSION MCUs_per_row; /* # of MCUs across the image */
449 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */
451 int blocks_in_MCU; /* # of DCT blocks per MCU */
452 int MCU_membership[C_MAX_BLOCKS_IN_MCU];
453 /* MCU_membership[i] is index in cur_comp_info of component owning */
454 /* i'th block in an MCU */
456 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */
458 #if JPEG_LIB_VERSION >= 80
459 int block_size; /* the basic DCT block size: 1..16 */
460 const int *natural_order; /* natural-order position array */
461 int lim_Se; /* min( Se, DCTSIZE2-1 ) */
465 * Links to compression subobjects (methods and private variables of modules)
467 struct jpeg_comp_master *master;
468 struct jpeg_c_main_controller *main;
469 struct jpeg_c_prep_controller *prep;
470 struct jpeg_c_coef_controller *coef;
471 struct jpeg_marker_writer *marker;
472 struct jpeg_color_converter *cconvert;
473 struct jpeg_downsampler *downsample;
474 struct jpeg_forward_dct *fdct;
475 struct jpeg_entropy_encoder *entropy;
476 jpeg_scan_info *script_space; /* workspace for jpeg_simple_progression */
477 int script_space_size;
481 /* Master record for a decompression instance */
483 struct jpeg_decompress_struct {
484 jpeg_common_fields; /* Fields shared with jpeg_compress_struct */
486 /* Source of compressed data */
487 struct jpeg_source_mgr *src;
489 /* Basic description of image --- filled in by jpeg_read_header(). */
490 /* Application may inspect these values to decide how to process image. */
492 JDIMENSION image_width; /* nominal image width (from SOF marker) */
493 JDIMENSION image_height; /* nominal image height */
494 int num_components; /* # of color components in JPEG image */
495 J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
497 /* Decompression processing parameters --- these fields must be set before
498 * calling jpeg_start_decompress(). Note that jpeg_read_header() initializes
499 * them to default values.
502 J_COLOR_SPACE out_color_space; /* colorspace for output */
504 unsigned int scale_num, scale_denom; /* fraction by which to scale image */
506 #if COLOR_PICKER_ENABLE == 1
507 unsigned int region_x, region_y, region_w, region_h; /* if region_w && region_h > 0, then use this region to decode. scale above is done prior to region select */
510 double output_gamma; /* image gamma wanted in output */
512 boolean buffered_image; /* TRUE=multiple output passes */
513 boolean raw_data_out; /* TRUE=downsampled data wanted */
515 J_DCT_METHOD dct_method; /* IDCT algorithm selector */
516 boolean do_fancy_upsampling; /* TRUE=apply fancy upsampling */
517 boolean do_block_smoothing; /* TRUE=apply interblock smoothing */
519 boolean quantize_colors; /* TRUE=colormapped output wanted */
520 /* the following are ignored if not quantize_colors: */
521 J_DITHER_MODE dither_mode; /* type of color dithering to use */
522 boolean two_pass_quantize; /* TRUE=use two-pass color quantization */
523 int desired_number_of_colors; /* max # colors to use in created colormap */
524 /* these are significant only in buffered-image mode: */
525 boolean enable_1pass_quant; /* enable future use of 1-pass quantizer */
526 boolean enable_external_quant;/* enable future use of external colormap */
527 boolean enable_2pass_quant; /* enable future use of 2-pass quantizer */
529 /* Description of actual output image that will be returned to application.
530 * These fields are computed by jpeg_start_decompress().
531 * You can also use jpeg_calc_output_dimensions() to determine these values
532 * in advance of calling jpeg_start_decompress().
535 JDIMENSION output_width; /* scaled image width */
536 JDIMENSION output_height; /* scaled image height */
537 int out_color_components; /* # of color components in out_color_space */
538 int output_components; /* # of color components returned */
539 /* output_components is 1 (a colormap index) when quantizing colors;
540 * otherwise it equals out_color_components.
542 int rec_outbuf_height; /* min recommended height of scanline buffer */
543 /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
544 * high, space and time will be wasted due to unnecessary data copying.
545 * Usually rec_outbuf_height will be 1 or 2, at most 4.
548 /* When quantizing colors, the output colormap is described by these fields.
549 * The application can supply a colormap by setting colormap non-NULL before
550 * calling jpeg_start_decompress; otherwise a colormap is created during
551 * jpeg_start_decompress or jpeg_start_output.
552 * The map has out_color_components rows and actual_number_of_colors columns.
554 int actual_number_of_colors; /* number of entries in use */
555 JSAMPARRAY colormap; /* The color map as a 2-D pixel array */
557 /* State variables: these variables indicate the progress of decompression.
558 * The application may examine these but must not modify them.
561 /* Row index of next scanline to be read from jpeg_read_scanlines().
562 * Application may use this to control its processing loop, e.g.,
563 * "while (output_scanline < output_height)".
565 JDIMENSION output_scanline; /* 0 .. output_height-1 */
567 /* Current input scan number and number of iMCU rows completed in scan.
568 * These indicate the progress of the decompressor input side.
570 int input_scan_number; /* Number of SOS markers seen so far */
571 JDIMENSION input_iMCU_row; /* Number of iMCU rows completed */
573 /* The "output scan number" is the notional scan being displayed by the
574 * output side. The decompressor will not allow output scan/row number
575 * to get ahead of input scan/row, but it can fall arbitrarily far behind.
577 int output_scan_number; /* Nominal scan number being displayed */
578 JDIMENSION output_iMCU_row; /* Number of iMCU rows read */
580 /* Current progression status. coef_bits[c][i] indicates the precision
581 * with which component c's DCT coefficient i (in zigzag order) is known.
582 * It is -1 when no data has yet been received, otherwise it is the point
583 * transform (shift) value for the most recent scan of the coefficient
584 * (thus, 0 at completion of the progression).
585 * This pointer is NULL when reading a non-progressive file.
587 int (*coef_bits)[DCTSIZE2]; /* -1 or current Al value for each coef */
589 /* Internal JPEG parameters --- the application usually need not look at
590 * these fields. Note that the decompressor output side may not use
591 * any parameters that can change between scans.
594 /* Quantization and Huffman tables are carried forward across input
595 * datastreams when processing abbreviated JPEG datastreams.
598 JQUANT_TBL *quant_tbl_ptrs[NUM_QUANT_TBLS];
599 /* ptrs to coefficient quantization tables, or NULL if not defined */
601 JHUFF_TBL *dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
602 JHUFF_TBL *ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
603 /* ptrs to Huffman coding tables, or NULL if not defined */
605 /* These parameters are never carried across datastreams, since they
606 * are given in SOF/SOS markers or defined to be reset by SOI.
609 int data_precision; /* bits of precision in image data */
611 jpeg_component_info *comp_info;
612 /* comp_info[i] describes component that appears i'th in SOF */
614 #if JPEG_LIB_VERSION >= 80
615 boolean is_baseline; /* TRUE if Baseline SOF0 encountered */
617 boolean progressive_mode; /* TRUE if SOFn specifies progressive mode */
618 boolean arith_code; /* TRUE=arithmetic coding, FALSE=Huffman */
620 UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
621 UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
622 UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
624 unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */
626 /* These fields record data obtained from optional markers recognized by
629 boolean saw_JFIF_marker; /* TRUE iff a JFIF APP0 marker was found */
630 /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */
631 UINT8 JFIF_major_version; /* JFIF version number */
632 UINT8 JFIF_minor_version;
633 UINT8 density_unit; /* JFIF code for pixel size units */
634 UINT16 X_density; /* Horizontal pixel density */
635 UINT16 Y_density; /* Vertical pixel density */
636 boolean saw_Adobe_marker; /* TRUE iff an Adobe APP14 marker was found */
637 UINT8 Adobe_transform; /* Color transform code from Adobe marker */
639 boolean CCIR601_sampling; /* TRUE=first samples are cosited */
641 /* Aside from the specific data retained from APPn markers known to the
642 * library, the uninterpreted contents of any or all APPn and COM markers
643 * can be saved in a list for examination by the application.
645 jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */
647 /* Remaining fields are known throughout decompressor, but generally
648 * should not be touched by a surrounding application.
652 * These fields are computed during decompression startup
654 int max_h_samp_factor; /* largest h_samp_factor */
655 int max_v_samp_factor; /* largest v_samp_factor */
657 #if JPEG_LIB_VERSION >= 70
658 int min_DCT_h_scaled_size; /* smallest DCT_h_scaled_size of any component */
659 int min_DCT_v_scaled_size; /* smallest DCT_v_scaled_size of any component */
661 int min_DCT_scaled_size; /* smallest DCT_scaled_size of any component */
664 JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */
665 /* The coefficient controller's input and output progress is measured in
666 * units of "iMCU" (interleaved MCU) rows. These are the same as MCU rows
667 * in fully interleaved JPEG scans, but are used whether the scan is
668 * interleaved or not. We define an iMCU row as v_samp_factor DCT block
669 * rows of each component. Therefore, the IDCT output contains
670 * v_samp_factor*DCT_[v_]scaled_size sample rows of a component per iMCU row.
673 JSAMPLE *sample_range_limit; /* table for fast range-limiting */
676 * These fields are valid during any one scan.
677 * They describe the components and MCUs actually appearing in the scan.
678 * Note that the decompressor output side must not use these fields.
680 int comps_in_scan; /* # of JPEG components in this scan */
681 jpeg_component_info *cur_comp_info[MAX_COMPS_IN_SCAN];
682 /* *cur_comp_info[i] describes component that appears i'th in SOS */
684 JDIMENSION MCUs_per_row; /* # of MCUs across the image */
685 JDIMENSION MCU_rows_in_scan; /* # of MCU rows in the image */
687 int blocks_in_MCU; /* # of DCT blocks per MCU */
688 int MCU_membership[D_MAX_BLOCKS_IN_MCU];
689 /* MCU_membership[i] is index in cur_comp_info of component owning */
690 /* i'th block in an MCU */
692 int Ss, Se, Ah, Al; /* progressive JPEG parameters for scan */
694 #if JPEG_LIB_VERSION >= 80
695 /* These fields are derived from Se of first SOS marker.
697 int block_size; /* the basic DCT block size: 1..16 */
698 const int *natural_order; /* natural-order position array for entropy decode */
699 int lim_Se; /* min( Se, DCTSIZE2-1 ) for entropy decode */
702 /* This field is shared between entropy decoder and marker parser.
703 * It is either zero or the code of a JPEG marker that has been
704 * read from the data source, but has not yet been processed.
709 * Links to decompression subobjects (methods, private variables of modules)
711 struct jpeg_decomp_master *master;
712 struct jpeg_d_main_controller *main;
713 struct jpeg_d_coef_controller *coef;
714 struct jpeg_d_post_controller *post;
715 struct jpeg_input_controller *inputctl;
716 struct jpeg_marker_reader *marker;
717 struct jpeg_entropy_decoder *entropy;
718 struct jpeg_inverse_dct *idct;
719 struct jpeg_upsampler *upsample;
720 struct jpeg_color_deconverter *cconvert;
721 struct jpeg_color_quantizer *cquantize;
723 #if COLOR_PICKER_ENABLE == 1
724 struct _Pick_Color_ *pick_color_data;
729 /* "Object" declarations for JPEG modules that may be supplied or called
730 * directly by the surrounding application.
731 * As with all objects in the JPEG library, these structs only define the
732 * publicly visible methods and state variables of a module. Additional
733 * private fields may exist after the public ones.
737 /* Error handler object */
739 struct jpeg_error_mgr {
740 /* Error exit handler: does not return to caller */
741 void (*error_exit) (j_common_ptr cinfo);
742 /* Conditionally emit a trace or warning message */
743 void (*emit_message) (j_common_ptr cinfo, int msg_level);
744 /* Routine that actually outputs a trace or error message */
745 void (*output_message) (j_common_ptr cinfo);
746 /* Format a message string for the most recent JPEG error or message */
747 void (*format_message) (j_common_ptr cinfo, char *buffer);
748 #define JMSG_LENGTH_MAX 200 /* recommended size of format_message buffer */
749 /* Reset error state variables at start of a new image */
750 void (*reset_error_mgr) (j_common_ptr cinfo);
752 /* The message ID code and any parameters are saved here.
753 * A message can have one string parameter or up to 8 int parameters.
756 #define JMSG_STR_PARM_MAX 80
759 char s[JMSG_STR_PARM_MAX];
762 /* Standard state variables for error facility */
764 int trace_level; /* max msg_level that will be displayed */
766 /* For recoverable corrupt-data errors, we emit a warning message,
767 * but keep going unless emit_message chooses to abort. emit_message
768 * should count warnings in num_warnings. The surrounding application
769 * can check for bad data by seeing if num_warnings is nonzero at the
772 long num_warnings; /* number of corrupt-data warnings */
774 /* These fields point to the table(s) of error message strings.
775 * An application can change the table pointer to switch to a different
776 * message list (typically, to change the language in which errors are
777 * reported). Some applications may wish to add additional error codes
778 * that will be handled by the JPEG library error mechanism; the second
779 * table pointer is used for this purpose.
781 * First table includes all errors generated by JPEG library itself.
782 * Error code 0 is reserved for a "no such error string" message.
784 const char * const *jpeg_message_table; /* Library errors */
785 int last_jpeg_message; /* Table contains strings 0..last_jpeg_message */
786 /* Second table can be added by application (see cjpeg/djpeg for example).
787 * It contains strings numbered first_addon_message..last_addon_message.
789 const char * const *addon_message_table; /* Non-library errors */
790 int first_addon_message; /* code for first string in addon table */
791 int last_addon_message; /* code for last string in addon table */
795 /* Progress monitor object */
797 struct jpeg_progress_mgr {
798 void (*progress_monitor) (j_common_ptr cinfo);
800 long pass_counter; /* work units completed in this pass */
801 long pass_limit; /* total number of work units in this pass */
802 int completed_passes; /* passes completed so far */
803 int total_passes; /* total number of passes expected */
807 /* Data destination object for compression */
809 struct jpeg_destination_mgr {
810 JOCTET *next_output_byte; /* => next byte to write in buffer */
811 size_t free_in_buffer; /* # of byte spaces remaining in buffer */
813 void (*init_destination) (j_compress_ptr cinfo);
814 boolean (*empty_output_buffer) (j_compress_ptr cinfo);
815 void (*term_destination) (j_compress_ptr cinfo);
819 /* Data source object for decompression */
821 struct jpeg_source_mgr {
822 const JOCTET *next_input_byte; /* => next byte to read from buffer */
823 size_t bytes_in_buffer; /* # of bytes remaining in buffer */
825 void (*init_source) (j_decompress_ptr cinfo);
826 boolean (*fill_input_buffer) (j_decompress_ptr cinfo);
827 void (*skip_input_data) (j_decompress_ptr cinfo, long num_bytes);
828 boolean (*resync_to_restart) (j_decompress_ptr cinfo, int desired);
829 void (*term_source) (j_decompress_ptr cinfo);
833 /* Memory manager object.
834 * Allocates "small" objects (a few K total), "large" objects (tens of K),
835 * and "really big" objects (virtual arrays with backing store if needed).
836 * The memory manager does not allow individual objects to be freed; rather,
837 * each created object is assigned to a pool, and whole pools can be freed
838 * at once. This is faster and more convenient than remembering exactly what
839 * to free, especially where malloc()/free() are not too speedy.
840 * NB: alloc routines never return NULL. They exit to error_exit if not
844 #define JPOOL_PERMANENT 0 /* lasts until master record is destroyed */
845 #define JPOOL_IMAGE 1 /* lasts until done with image/datastream */
846 #define JPOOL_NUMPOOLS 2
848 typedef struct jvirt_sarray_control *jvirt_sarray_ptr;
849 typedef struct jvirt_barray_control *jvirt_barray_ptr;
852 struct jpeg_memory_mgr {
853 /* Method pointers */
854 void *(*alloc_small) (j_common_ptr cinfo, int pool_id, size_t sizeofobject);
855 void *(*alloc_large) (j_common_ptr cinfo, int pool_id,
856 size_t sizeofobject);
857 JSAMPARRAY (*alloc_sarray) (j_common_ptr cinfo, int pool_id,
858 JDIMENSION samplesperrow, JDIMENSION numrows);
859 JBLOCKARRAY (*alloc_barray) (j_common_ptr cinfo, int pool_id,
860 JDIMENSION blocksperrow, JDIMENSION numrows);
861 jvirt_sarray_ptr (*request_virt_sarray) (j_common_ptr cinfo, int pool_id,
863 JDIMENSION samplesperrow,
865 JDIMENSION maxaccess);
866 jvirt_barray_ptr (*request_virt_barray) (j_common_ptr cinfo, int pool_id,
868 JDIMENSION blocksperrow,
870 JDIMENSION maxaccess);
871 void (*realize_virt_arrays) (j_common_ptr cinfo);
872 JSAMPARRAY (*access_virt_sarray) (j_common_ptr cinfo, jvirt_sarray_ptr ptr,
873 JDIMENSION start_row, JDIMENSION num_rows,
875 JBLOCKARRAY (*access_virt_barray) (j_common_ptr cinfo, jvirt_barray_ptr ptr,
876 JDIMENSION start_row, JDIMENSION num_rows,
878 void (*free_pool) (j_common_ptr cinfo, int pool_id);
879 void (*self_destruct) (j_common_ptr cinfo);
881 /* Limit on memory allocation for this JPEG object. (Note that this is
882 * merely advisory, not a guaranteed maximum; it only affects the space
883 * used for virtual-array buffers.) May be changed by outer application
884 * after creating the JPEG object.
886 long max_memory_to_use;
888 /* Maximum allocation request accepted by alloc_large. */
889 long max_alloc_chunk;
893 /* Routine signature for application-supplied marker processing methods.
894 * Need not pass marker code since it is stored in cinfo->unread_marker.
896 typedef boolean (*jpeg_marker_parser_method) (j_decompress_ptr cinfo);
899 /* Originally, this macro was used as a way of defining function prototypes
900 * for both modern compilers as well as older compilers that did not support
901 * prototype parameters. libjpeg-turbo has never supported these older,
902 * non-ANSI compilers, but the macro is still included because there is some
903 * software out there that uses it.
906 #define JPP(arglist) arglist
909 /* Default error-management setup */
910 EXTERN(struct jpeg_error_mgr *) jpeg_std_error(struct jpeg_error_mgr *err);
912 /* Initialization of JPEG compression objects.
913 * jpeg_create_compress() and jpeg_create_decompress() are the exported
914 * names that applications should call. These expand to calls on
915 * jpeg_CreateCompress and jpeg_CreateDecompress with additional information
916 * passed for version mismatch checking.
917 * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx.
919 #define jpeg_create_compress(cinfo) \
920 jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \
921 (size_t)sizeof(struct jpeg_compress_struct))
922 #define jpeg_create_decompress(cinfo) \
923 jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \
924 (size_t)sizeof(struct jpeg_decompress_struct))
925 EXTERN(void) jpeg_CreateCompress(j_compress_ptr cinfo, int version,
927 EXTERN(void) jpeg_CreateDecompress(j_decompress_ptr cinfo, int version,
929 /* Destruction of JPEG compression objects */
930 EXTERN(void) jpeg_destroy_compress(j_compress_ptr cinfo);
931 EXTERN(void) jpeg_destroy_decompress(j_decompress_ptr cinfo);
933 /* Standard data source and destination managers: stdio streams. */
934 /* Caller is responsible for opening the file before and closing after. */
935 EXTERN(void) jpeg_stdio_dest(j_compress_ptr cinfo, FILE *outfile);
936 EXTERN(void) jpeg_stdio_src(j_decompress_ptr cinfo, FILE *infile);
938 #if JPEG_LIB_VERSION >= 80 || defined(MEM_SRCDST_SUPPORTED)
939 /* Data source and destination managers: memory buffers. */
940 EXTERN(void) jpeg_mem_dest(j_compress_ptr cinfo, unsigned char **outbuffer,
941 unsigned long *outsize);
942 EXTERN(void) jpeg_mem_src(j_decompress_ptr cinfo,
943 const unsigned char *inbuffer, unsigned long insize);
946 /* Default parameter setup for compression */
947 EXTERN(void) jpeg_set_defaults(j_compress_ptr cinfo);
948 /* Compression parameter setup aids */
949 EXTERN(void) jpeg_set_colorspace(j_compress_ptr cinfo,
950 J_COLOR_SPACE colorspace);
951 EXTERN(void) jpeg_default_colorspace(j_compress_ptr cinfo);
952 EXTERN(void) jpeg_set_quality(j_compress_ptr cinfo, int quality,
953 boolean force_baseline);
954 EXTERN(void) jpeg_set_linear_quality(j_compress_ptr cinfo, int scale_factor,
955 boolean force_baseline);
956 #if JPEG_LIB_VERSION >= 70
957 EXTERN(void) jpeg_default_qtables(j_compress_ptr cinfo,
958 boolean force_baseline);
960 EXTERN(void) jpeg_add_quant_table(j_compress_ptr cinfo, int which_tbl,
961 const unsigned int *basic_table,
962 int scale_factor, boolean force_baseline);
963 EXTERN(int) jpeg_quality_scaling(int quality);
964 EXTERN(void) jpeg_simple_progression(j_compress_ptr cinfo);
965 EXTERN(void) jpeg_suppress_tables(j_compress_ptr cinfo, boolean suppress);
966 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table(j_common_ptr cinfo);
967 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table(j_common_ptr cinfo);
969 /* Main entry points for compression */
970 EXTERN(void) jpeg_start_compress(j_compress_ptr cinfo,
971 boolean write_all_tables);
972 EXTERN(JDIMENSION) jpeg_write_scanlines(j_compress_ptr cinfo,
973 JSAMPARRAY scanlines,
974 JDIMENSION num_lines);
975 EXTERN(void) jpeg_finish_compress(j_compress_ptr cinfo);
977 #if JPEG_LIB_VERSION >= 70
978 /* Precalculate JPEG dimensions for current compression parameters. */
979 EXTERN(void) jpeg_calc_jpeg_dimensions(j_compress_ptr cinfo);
982 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
983 EXTERN(JDIMENSION) jpeg_write_raw_data(j_compress_ptr cinfo, JSAMPIMAGE data,
984 JDIMENSION num_lines);
986 /* Write a special marker. See libjpeg.txt concerning safe usage. */
987 EXTERN(void) jpeg_write_marker(j_compress_ptr cinfo, int marker,
988 const JOCTET *dataptr, unsigned int datalen);
989 /* Same, but piecemeal. */
990 EXTERN(void) jpeg_write_m_header(j_compress_ptr cinfo, int marker,
991 unsigned int datalen);
992 EXTERN(void) jpeg_write_m_byte(j_compress_ptr cinfo, int val);
994 /* Alternate compression function: just write an abbreviated table file */
995 EXTERN(void) jpeg_write_tables(j_compress_ptr cinfo);
997 /* Write ICC profile. See libjpeg.txt for usage information. */
998 EXTERN(void) jpeg_write_icc_profile(j_compress_ptr cinfo,
999 const JOCTET *icc_data_ptr,
1000 unsigned int icc_data_len);
1003 /* Decompression startup: read start of JPEG datastream to see what's there */
1004 EXTERN(int) jpeg_read_header(j_decompress_ptr cinfo, boolean require_image);
1005 /* Return value is one of: */
1006 #define JPEG_SUSPENDED 0 /* Suspended due to lack of input data */
1007 #define JPEG_HEADER_OK 1 /* Found valid image datastream */
1008 #define JPEG_HEADER_TABLES_ONLY 2 /* Found valid table-specs-only datastream */
1009 /* If you pass require_image = TRUE (normal case), you need not check for
1010 * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
1011 * JPEG_SUSPENDED is only possible if you use a data source module that can
1012 * give a suspension return (the stdio source module doesn't).
1015 /* Main entry points for decompression */
1016 EXTERN(boolean) jpeg_start_decompress(j_decompress_ptr cinfo);
1017 EXTERN(JDIMENSION) jpeg_read_scanlines(j_decompress_ptr cinfo,
1018 JSAMPARRAY scanlines,
1019 JDIMENSION max_lines);
1020 EXTERN(JDIMENSION) jpeg_skip_scanlines(j_decompress_ptr cinfo,
1021 JDIMENSION num_lines);
1022 EXTERN(void) jpeg_crop_scanline(j_decompress_ptr cinfo, JDIMENSION *xoffset,
1024 EXTERN(boolean) jpeg_finish_decompress(j_decompress_ptr cinfo);
1026 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
1027 EXTERN(JDIMENSION) jpeg_read_raw_data(j_decompress_ptr cinfo, JSAMPIMAGE data,
1028 JDIMENSION max_lines);
1030 /* Additional entry points for buffered-image mode. */
1031 EXTERN(boolean) jpeg_has_multiple_scans(j_decompress_ptr cinfo);
1032 EXTERN(boolean) jpeg_start_output(j_decompress_ptr cinfo, int scan_number);
1033 EXTERN(boolean) jpeg_finish_output(j_decompress_ptr cinfo);
1034 EXTERN(boolean) jpeg_input_complete(j_decompress_ptr cinfo);
1035 EXTERN(void) jpeg_new_colormap(j_decompress_ptr cinfo);
1036 EXTERN(int) jpeg_consume_input(j_decompress_ptr cinfo);
1037 /* Return value is one of: */
1038 /* #define JPEG_SUSPENDED 0 Suspended due to lack of input data */
1039 #define JPEG_REACHED_SOS 1 /* Reached start of new scan */
1040 #define JPEG_REACHED_EOI 2 /* Reached end of image */
1041 #define JPEG_ROW_COMPLETED 3 /* Completed one iMCU row */
1042 #define JPEG_SCAN_COMPLETED 4 /* Completed last iMCU row of a scan */
1044 /* Precalculate output dimensions for current decompression parameters. */
1045 #if JPEG_LIB_VERSION >= 80
1046 EXTERN(void) jpeg_core_output_dimensions(j_decompress_ptr cinfo);
1048 EXTERN(void) jpeg_calc_output_dimensions(j_decompress_ptr cinfo);
1050 /* Control saving of COM and APPn markers into marker_list. */
1051 EXTERN(void) jpeg_save_markers(j_decompress_ptr cinfo, int marker_code,
1052 unsigned int length_limit);
1054 /* Install a special processing method for COM or APPn markers. */
1055 EXTERN(void) jpeg_set_marker_processor(j_decompress_ptr cinfo,
1057 jpeg_marker_parser_method routine);
1059 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */
1060 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients(j_decompress_ptr cinfo);
1061 EXTERN(void) jpeg_write_coefficients(j_compress_ptr cinfo,
1062 jvirt_barray_ptr *coef_arrays);
1063 EXTERN(void) jpeg_copy_critical_parameters(j_decompress_ptr srcinfo,
1064 j_compress_ptr dstinfo);
1066 /* If you choose to abort compression or decompression before completing
1067 * jpeg_finish_(de)compress, then you need to clean up to release memory,
1068 * temporary files, etc. You can just call jpeg_destroy_(de)compress
1069 * if you're done with the JPEG object, but if you want to clean it up and
1070 * reuse it, call this:
1072 EXTERN(void) jpeg_abort_compress(j_compress_ptr cinfo);
1073 EXTERN(void) jpeg_abort_decompress(j_decompress_ptr cinfo);
1075 /* Generic versions of jpeg_abort and jpeg_destroy that work on either
1076 * flavor of JPEG object. These may be more convenient in some places.
1078 EXTERN(void) jpeg_abort(j_common_ptr cinfo);
1079 EXTERN(void) jpeg_destroy(j_common_ptr cinfo);
1081 /* Default restart-marker-resync procedure for use by data source modules */
1082 EXTERN(boolean) jpeg_resync_to_restart(j_decompress_ptr cinfo, int desired);
1084 /* Read ICC profile. See libjpeg.txt for usage information. */
1085 EXTERN(boolean) jpeg_read_icc_profile(j_decompress_ptr cinfo,
1086 JOCTET **icc_data_ptr,
1087 unsigned int *icc_data_len);
1090 /* These marker codes are exported since applications and data source modules
1091 * are likely to want to use them.
1094 #define JPEG_RST0 0xD0 /* RST0 marker code */
1095 #define JPEG_EOI 0xD9 /* EOI marker code */
1096 #define JPEG_APP0 0xE0 /* APP0 marker code */
1097 #define JPEG_COM 0xFE /* COM marker code */
1100 /* If we have a brain-damaged compiler that emits warnings (or worse, errors)
1101 * for structure definitions that are never filled in, keep it quiet by
1102 * supplying dummy definitions for the various substructures.
1105 #ifdef INCOMPLETE_TYPES_BROKEN
1106 #ifndef JPEG_INTERNALS /* will be defined in jpegint.h */
1107 struct jvirt_sarray_control { long dummy; };
1108 struct jvirt_barray_control { long dummy; };
1109 struct jpeg_comp_master { long dummy; };
1110 struct jpeg_c_main_controller { long dummy; };
1111 struct jpeg_c_prep_controller { long dummy; };
1112 struct jpeg_c_coef_controller { long dummy; };
1113 struct jpeg_marker_writer { long dummy; };
1114 struct jpeg_color_converter { long dummy; };
1115 struct jpeg_downsampler { long dummy; };
1116 struct jpeg_forward_dct { long dummy; };
1117 struct jpeg_entropy_encoder { long dummy; };
1118 struct jpeg_decomp_master { long dummy; };
1119 struct jpeg_d_main_controller { long dummy; };
1120 struct jpeg_d_coef_controller { long dummy; };
1121 struct jpeg_d_post_controller { long dummy; };
1122 struct jpeg_input_controller { long dummy; };
1123 struct jpeg_marker_reader { long dummy; };
1124 struct jpeg_entropy_decoder { long dummy; };
1125 struct jpeg_inverse_dct { long dummy; };
1126 struct jpeg_upsampler { long dummy; };
1127 struct jpeg_color_deconverter { long dummy; };
1128 struct jpeg_color_quantizer { long dummy; };
1129 #endif /* JPEG_INTERNALS */
1130 #endif /* INCOMPLETE_TYPES_BROKEN */
1134 * The JPEG library modules define JPEG_INTERNALS before including this file.
1135 * The internal structure declarations are read only when that is true.
1136 * Applications using the library should not include jpegint.h, but may wish
1137 * to include jerror.h.
1140 #ifdef JPEG_INTERNALS
1141 #include "jpegint.h" /* fetch private declarations */
1142 #include "jerror.h" /* fetch error codes too */
1146 #ifndef DONT_USE_EXTERN_C
1151 #endif /* JPEGLIB_H */