1 /*
2  * jpeglib.h
3  *
4  * Copyright (C) 1991-1998, Thomas G. Lane.
5  * This file is part of the Independent JPEG Group's software.
6  * For conditions of distribution and use, see the accompanying README file.
7  *
8  * This file defines the application interface for the JPEG library.
9  * Most applications using the library need only include this file,
10  * and perhaps jerror.h if they want to know the exact error codes.
11  */
12 
13 #ifndef JPEGLIB_H
14 #define JPEGLIB_H
15 
16 #define FOXIT_PREFIX(origName)  FPDFAPIJPEG_##origName
17 
18 #define jcopy_block_row FOXIT_PREFIX(jcopy_block_row)
19 #define jcopy_sample_rows FOXIT_PREFIX(jcopy_sample_rows)
20 #define jdiv_round_up FOXIT_PREFIX(jdiv_round_up)
21 #define jinit_1pass_quantizer FOXIT_PREFIX(jinit_1pass_quantizer)
22 #define jinit_2pass_quantizer FOXIT_PREFIX(jinit_2pass_quantizer)
23 #define jinit_c_coef_controller FOXIT_PREFIX(jinit_c_coef_controller)
24 #define jinit_c_main_controller FOXIT_PREFIX(jinit_c_main_controller)
25 #define jinit_c_master_control FOXIT_PREFIX(jinit_c_master_control)
26 #define jinit_c_prep_controller FOXIT_PREFIX(jinit_c_prep_controller)
27 #define jinit_color_converter FOXIT_PREFIX(jinit_color_converter)
28 #define jinit_color_deconverter FOXIT_PREFIX(jinit_color_deconverter)
29 #define jinit_compress_master FOXIT_PREFIX(jinit_compress_master)
30 #define jinit_d_coef_controller FOXIT_PREFIX(jinit_d_coef_controller)
31 #define jinit_d_main_controller FOXIT_PREFIX(jinit_d_main_controller)
32 #define jinit_d_post_controller FOXIT_PREFIX(jinit_d_post_controller)
33 #define jinit_downsampler FOXIT_PREFIX(jinit_downsampler)
34 #define jinit_forward_dct FOXIT_PREFIX(jinit_forward_dct)
35 #define jinit_huff_decoder FOXIT_PREFIX(jinit_huff_decoder)
36 #define jinit_huff_encoder FOXIT_PREFIX(jinit_huff_encoder)
37 #define jinit_input_controller FOXIT_PREFIX(jinit_input_controller)
38 #define jinit_inverse_dct FOXIT_PREFIX(jinit_inverse_dct)
39 #define jinit_marker_reader FOXIT_PREFIX(jinit_marker_reader)
40 #define jinit_marker_writer FOXIT_PREFIX(jinit_marker_writer)
41 #define jinit_master_decompress FOXIT_PREFIX(jinit_master_decompress)
42 #define jinit_memory_mgr FOXIT_PREFIX(jinit_memory_mgr)
43 #define jinit_merged_upsampler FOXIT_PREFIX(jinit_merged_upsampler)
44 #define jinit_phuff_decoder FOXIT_PREFIX(jinit_phuff_decoder)
45 #define jinit_phuff_encoder FOXIT_PREFIX(jinit_phuff_encoder)
46 #define jinit_upsampler FOXIT_PREFIX(jinit_upsampler)
47 #define jpeg_CreateCompress FOXIT_PREFIX(jpeg_CreateCompress)
48 #define jpeg_CreateDecompress FOXIT_PREFIX(jpeg_CreateDecompress)
49 #define jpeg_abort FOXIT_PREFIX(jpeg_abort)
50 #define jpeg_abort_compress FOXIT_PREFIX(jpeg_abort_compress)
51 #define jpeg_abort_decompress FOXIT_PREFIX(jpeg_abort_decompress)
52 #define jpeg_add_quant_table FOXIT_PREFIX(jpeg_add_quant_table)
53 #define jpeg_alloc_huff_table FOXIT_PREFIX(jpeg_alloc_huff_table)
54 #define jpeg_alloc_quant_table FOXIT_PREFIX(jpeg_alloc_quant_table)
55 #define jpeg_calc_output_dimensions FOXIT_PREFIX(jpeg_calc_output_dimensions)
56 #define jpeg_consume_input FOXIT_PREFIX(jpeg_consume_input)
57 #define jpeg_default_colorspace FOXIT_PREFIX(jpeg_default_colorspace)
58 #define jpeg_destroy FOXIT_PREFIX(jpeg_destroy)
59 #define jpeg_destroy_compress FOXIT_PREFIX(jpeg_destroy_compress)
60 #define jpeg_destroy_decompress FOXIT_PREFIX(jpeg_destroy_decompress)
61 #define jpeg_fdct_ifast FOXIT_PREFIX(jpeg_fdct_ifast)
62 #define jpeg_fdct_islow FOXIT_PREFIX(jpeg_fdct_islow)
63 #define jpeg_fill_bit_buffer FOXIT_PREFIX(jpeg_fill_bit_buffer)
64 #define jpeg_finish_compress FOXIT_PREFIX(jpeg_finish_compress)
65 #define jpeg_finish_decompress FOXIT_PREFIX(jpeg_finish_decompress)
66 #define jpeg_finish_output FOXIT_PREFIX(jpeg_finish_output)
67 #define jpeg_free_large FOXIT_PREFIX(jpeg_free_large)
68 #define jpeg_free_small FOXIT_PREFIX(jpeg_free_small)
69 #define jpeg_gen_optimal_table FOXIT_PREFIX(jpeg_gen_optimal_table)
70 #define jpeg_get_large FOXIT_PREFIX(jpeg_get_large)
71 #define jpeg_get_small FOXIT_PREFIX(jpeg_get_small)
72 #define jpeg_has_multiple_scans FOXIT_PREFIX(jpeg_has_multiple_scans)
73 #define jpeg_huff_decode FOXIT_PREFIX(jpeg_huff_decode)
74 #define jpeg_idct_1x1 FOXIT_PREFIX(jpeg_idct_1x1)
75 #define jpeg_idct_2x2 FOXIT_PREFIX(jpeg_idct_2x2)
76 #define jpeg_idct_4x4 FOXIT_PREFIX(jpeg_idct_4x4)
77 #define jpeg_idct_float FOXIT_PREFIX(jpeg_idct_float)
78 #define jpeg_idct_ifast FOXIT_PREFIX(jpeg_idct_ifast)
79 #define jpeg_idct_islow FOXIT_PREFIX(jpeg_idct_islow)
80 #define jpeg_input_complete FOXIT_PREFIX(jpeg_input_complete)
81 #define jpeg_make_c_derived_tbl FOXIT_PREFIX(jpeg_make_c_derived_tbl)
82 #define jpeg_make_d_derived_tbl FOXIT_PREFIX(jpeg_make_d_derived_tbl)
83 #define jpeg_mem_available FOXIT_PREFIX(jpeg_mem_available)
84 #define jpeg_mem_init FOXIT_PREFIX(jpeg_mem_init)
85 #define jpeg_mem_term FOXIT_PREFIX(jpeg_mem_term)
86 #define jpeg_natural_order FOXIT_PREFIX(jpeg_natural_order)
87 #define jpeg_new_colormap FOXIT_PREFIX(jpeg_new_colormap)
88 #define jpeg_open_backing_store FOXIT_PREFIX(jpeg_open_backing_store)
89 #define jpeg_quality_scaling FOXIT_PREFIX(jpeg_quality_scaling)
90 #define jpeg_read_coefficients FOXIT_PREFIX(jpeg_read_coefficients)
91 #define jpeg_read_header FOXIT_PREFIX(jpeg_read_header)
92 #define jpeg_read_raw_data FOXIT_PREFIX(jpeg_read_raw_data)
93 #define jpeg_read_scanlines FOXIT_PREFIX(jpeg_read_scanlines)
94 #define jpeg_resync_to_restart FOXIT_PREFIX(jpeg_resync_to_restart)
95 #define jpeg_save_markers FOXIT_PREFIX(jpeg_save_markers)
96 #define jpeg_set_colorspace FOXIT_PREFIX(jpeg_set_colorspace)
97 #define jpeg_set_defaults FOXIT_PREFIX(jpeg_set_defaults)
98 #define jpeg_set_linear_quality FOXIT_PREFIX(jpeg_set_linear_quality)
99 #define jpeg_set_marker_processor FOXIT_PREFIX(jpeg_set_marker_processor)
100 #define jpeg_set_quality FOXIT_PREFIX(jpeg_set_quality)
101 #define jpeg_simple_progression FOXIT_PREFIX(jpeg_simple_progression)
102 #define jpeg_start_compress FOXIT_PREFIX(jpeg_start_compress)
103 #define jpeg_start_decompress FOXIT_PREFIX(jpeg_start_decompress)
104 #define jpeg_start_output FOXIT_PREFIX(jpeg_start_output)
105 #define jpeg_std_error FOXIT_PREFIX(jpeg_std_error)
106 #define jpeg_std_message_table FOXIT_PREFIX(jpeg_std_message_table)
107 #define jpeg_stdio_src FOXIT_PREFIX(jpeg_stdio_src)
108 #define jpeg_suppress_tables FOXIT_PREFIX(jpeg_suppress_tables)
109 #define jpeg_write_m_byte FOXIT_PREFIX(jpeg_write_m_byte)
110 #define jpeg_write_m_header FOXIT_PREFIX(jpeg_write_m_header)
111 #define jpeg_write_marker FOXIT_PREFIX(jpeg_write_marker)
112 #define jpeg_write_raw_data FOXIT_PREFIX(jpeg_write_raw_data)
113 #define jpeg_write_scanlines FOXIT_PREFIX(jpeg_write_scanlines)
114 #define jpeg_write_tables FOXIT_PREFIX(jpeg_write_tables)
115 #define jround_up FOXIT_PREFIX(jround_up)
116 #define jzero_far FOXIT_PREFIX(jzero_far)
117 
118  /*
119  * First we include the configuration files that record how this
120  * installation of the JPEG library is set up.  jconfig.h can be
121  * generated automatically for many systems.  jmorecfg.h contains
122  * manual configuration options that most people need not worry about.
123  */
124 
125 #ifndef JCONFIG_INCLUDED	/* in case jinclude.h already did */
126 #include "jconfig.h"		/* widely used configuration options */
127 #endif
128 #include "jmorecfg.h"		/* seldom changed options */
129 
130 
131 /* Version ID for the JPEG library.
132  * Might be useful for tests like "#if JPEG_LIB_VERSION >= 60".
133  */
134 
135 #define JPEG_LIB_VERSION  62	/* Version 6b */
136 
137 
138 /* Various constants determining the sizes of things.
139  * All of these are specified by the JPEG standard, so don't change them
140  * if you want to be compatible.
141  */
142 
143 #define DCTSIZE		    8	/* The basic DCT block is 8x8 samples */
144 #define DCTSIZE2	    64	/* DCTSIZE squared; # of elements in a block */
145 #define NUM_QUANT_TBLS      4	/* Quantization tables are numbered 0..3 */
146 #define NUM_HUFF_TBLS       4	/* Huffman tables are numbered 0..3 */
147 #define NUM_ARITH_TBLS      16	/* Arith-coding tables are numbered 0..15 */
148 #define MAX_COMPS_IN_SCAN   4	/* JPEG limit on # of components in one scan */
149 #define MAX_SAMP_FACTOR     4	/* JPEG limit on sampling factors */
150 /* Unfortunately, some bozo at Adobe saw no reason to be bound by the standard;
151  * the PostScript DCT filter can emit files with many more than 10 blocks/MCU.
152  * If you happen to run across such a file, you can up D_MAX_BLOCKS_IN_MCU
153  * to handle it.  We even let you do this from the jconfig.h file.  However,
154  * we strongly discourage changing C_MAX_BLOCKS_IN_MCU; just because Adobe
155  * sometimes emits noncompliant files doesn't mean you should too.
156  */
157 #define C_MAX_BLOCKS_IN_MCU   10 /* compressor's limit on blocks per MCU */
158 #ifndef D_MAX_BLOCKS_IN_MCU
159 #define D_MAX_BLOCKS_IN_MCU   10 /* decompressor's limit on blocks per MCU */
160 #endif
161 
162 
163 /* Data structures for images (arrays of samples and of DCT coefficients).
164  * On 80x86 machines, the image arrays are too big for near pointers,
165  * but the pointer arrays can fit in near memory.
166  */
167 
168 typedef JSAMPLE  *JSAMPROW;	/* ptr to one image row of pixel samples. */
169 typedef JSAMPROW *JSAMPARRAY;	/* ptr to some rows (a 2-D sample array) */
170 typedef JSAMPARRAY *JSAMPIMAGE;	/* a 3-D sample array: top index is color */
171 
172 typedef JCOEF JBLOCK[DCTSIZE2];	/* one block of coefficients */
173 typedef JBLOCK  *JBLOCKROW;	/* pointer to one row of coefficient blocks */
174 typedef JBLOCKROW *JBLOCKARRAY;		/* a 2-D array of coefficient blocks */
175 typedef JBLOCKARRAY *JBLOCKIMAGE;	/* a 3-D array of coefficient blocks */
176 
177 typedef JCOEF  *JCOEFPTR;	/* useful in a couple of places */
178 
179 
180 /* Types for JPEG compression parameters and working tables. */
181 
182 
183 /* DCT coefficient quantization tables. */
184 
185 typedef struct {
186   /* This array gives the coefficient quantizers in natural array order
187    * (not the zigzag order in which they are stored in a JPEG DQT marker).
188    * CAUTION: IJG versions prior to v6a kept this array in zigzag order.
189    */
190   UINT16 quantval[DCTSIZE2];	/* quantization step for each coefficient */
191   /* This field is used only during compression.  It's initialized FALSE when
192    * the table is created, and set TRUE when it's been output to the file.
193    * You could suppress output of a table by setting this to TRUE.
194    * (See jpeg_suppress_tables for an example.)
195    */
196   boolean sent_table;		/* TRUE when table has been output */
197 } JQUANT_TBL;
198 
199 
200 /* Huffman coding tables. */
201 
202 typedef struct {
203   /* These two fields directly represent the contents of a JPEG DHT marker */
204   UINT8 bits[17];		/* bits[k] = # of symbols with codes of */
205 				/* length k bits; bits[0] is unused */
206   UINT8 huffval[256];		/* The symbols, in order of incr code length */
207   /* This field is used only during compression.  It's initialized FALSE when
208    * the table is created, and set TRUE when it's been output to the file.
209    * You could suppress output of a table by setting this to TRUE.
210    * (See jpeg_suppress_tables for an example.)
211    */
212   boolean sent_table;		/* TRUE when table has been output */
213 } JHUFF_TBL;
214 
215 
216 /* Basic info about one component (color channel). */
217 
218 typedef struct {
219   /* These values are fixed over the whole image. */
220   /* For compression, they must be supplied by parameter setup; */
221   /* for decompression, they are read from the SOF marker. */
222   int component_id;		/* identifier for this component (0..255) */
223   int component_index;		/* its index in SOF or cinfo->comp_info[] */
224   int h_samp_factor;		/* horizontal sampling factor (1..4) */
225   int v_samp_factor;		/* vertical sampling factor (1..4) */
226   int quant_tbl_no;		/* quantization table selector (0..3) */
227   /* These values may vary between scans. */
228   /* For compression, they must be supplied by parameter setup; */
229   /* for decompression, they are read from the SOS marker. */
230   /* The decompressor output side may not use these variables. */
231   int dc_tbl_no;		/* DC entropy table selector (0..3) */
232   int ac_tbl_no;		/* AC entropy table selector (0..3) */
233 
234   /* Remaining fields should be treated as private by applications. */
235 
236   /* These values are computed during compression or decompression startup: */
237   /* Component's size in DCT blocks.
238    * Any dummy blocks added to complete an MCU are not counted; therefore
239    * these values do not depend on whether a scan is interleaved or not.
240    */
241   JDIMENSION width_in_blocks;
242   JDIMENSION height_in_blocks;
243   /* Size of a DCT block in samples.  Always DCTSIZE for compression.
244    * For decompression this is the size of the output from one DCT block,
245    * reflecting any scaling we choose to apply during the IDCT step.
246    * Values of 1,2,4,8 are likely to be supported.  Note that different
247    * components may receive different IDCT scalings.
248    */
249   int DCT_scaled_size;
250   /* The downsampled dimensions are the component's actual, unpadded number
251    * of samples at the main buffer (preprocessing/compression interface), thus
252    * downsampled_width = ceil(image_width * Hi/Hmax)
253    * and similarly for height.  For decompression, IDCT scaling is included, so
254    * downsampled_width = ceil(image_width * Hi/Hmax * DCT_scaled_size/DCTSIZE)
255    */
256   JDIMENSION downsampled_width;	 /* actual width in samples */
257   JDIMENSION downsampled_height; /* actual height in samples */
258   /* This flag is used only for decompression.  In cases where some of the
259    * components will be ignored (eg grayscale output from YCbCr image),
260    * we can skip most computations for the unused components.
261    */
262   boolean component_needed;	/* do we need the value of this component? */
263 
264   /* These values are computed before starting a scan of the component. */
265   /* The decompressor output side may not use these variables. */
266   int MCU_width;		/* number of blocks per MCU, horizontally */
267   int MCU_height;		/* number of blocks per MCU, vertically */
268   int MCU_blocks;		/* MCU_width * MCU_height */
269   int MCU_sample_width;		/* MCU width in samples, MCU_width*DCT_scaled_size */
270   int last_col_width;		/* # of non-dummy blocks across in last MCU */
271   int last_row_height;		/* # of non-dummy blocks down in last MCU */
272 
273   /* Saved quantization table for component; NULL if none yet saved.
274    * See jdinput.c comments about the need for this information.
275    * This field is currently used only for decompression.
276    */
277   JQUANT_TBL * quant_table;
278 
279   /* Private per-component storage for DCT or IDCT subsystem. */
280   void * dct_table;
281 } jpeg_component_info;
282 
283 
284 /* The script for encoding a multiple-scan file is an array of these: */
285 
286 typedef struct {
287   int comps_in_scan;		/* number of components encoded in this scan */
288   int component_index[MAX_COMPS_IN_SCAN]; /* their SOF/comp_info[] indexes */
289   int Ss, Se;			/* progressive JPEG spectral selection parms */
290   int Ah, Al;			/* progressive JPEG successive approx. parms */
291 } jpeg_scan_info;
292 
293 /* The decompressor can save APPn and COM markers in a list of these: */
294 
295 typedef struct jpeg_marker_struct  * jpeg_saved_marker_ptr;
296 
297 struct jpeg_marker_struct {
298   jpeg_saved_marker_ptr next;	/* next in list, or NULL */
299   UINT8 marker;			/* marker code: JPEG_COM, or JPEG_APP0+n */
300   unsigned int original_length;	/* # bytes of data in the file */
301   unsigned int data_length;	/* # bytes of data saved at data[] */
302   JOCTET  * data;		/* the data contained in the marker */
303   /* the marker length word is not counted in data_length or original_length */
304 };
305 
306 /* Known color spaces. */
307 
308 typedef enum {
309 	JCS_UNKNOWN,		/* error/unspecified */
310 	JCS_GRAYSCALE,		/* monochrome */
311 	JCS_RGB,		/* red/green/blue */
312 	JCS_YCbCr,		/* Y/Cb/Cr (also known as YUV) */
313 	JCS_CMYK,		/* C/M/Y/K */
314 	JCS_YCCK		/* Y/Cb/Cr/K */
315 } J_COLOR_SPACE;
316 
317 /* DCT/IDCT algorithm options. */
318 
319 typedef enum {
320 	JDCT_ISLOW,		/* slow but accurate integer algorithm */
321 	JDCT_IFAST,		/* faster, less accurate integer method */
322 	JDCT_FLOAT		/* floating-point: accurate, fast on fast HW */
323 } J_DCT_METHOD;
324 
325 #ifndef JDCT_DEFAULT		/* may be overridden in jconfig.h */
326 #define JDCT_DEFAULT  JDCT_ISLOW
327 #endif
328 #ifndef JDCT_FASTEST		/* may be overridden in jconfig.h */
329 #define JDCT_FASTEST  JDCT_IFAST
330 #endif
331 
332 /* Dithering options for decompression. */
333 
334 typedef enum {
335 	JDITHER_NONE,		/* no dithering */
336 	JDITHER_ORDERED,	/* simple ordered dither */
337 	JDITHER_FS		/* Floyd-Steinberg error diffusion dither */
338 } J_DITHER_MODE;
339 
340 
341 /* Common fields between JPEG compression and decompression master structs. */
342 
343 #define jpeg_common_fields \
344   struct jpeg_error_mgr * err;	/* Error handler module */\
345   struct jpeg_memory_mgr * mem;	/* Memory manager module */\
346   struct jpeg_progress_mgr * progress; /* Progress monitor, or NULL if none */\
347   void * client_data;		/* Available for use by application */\
348   boolean is_decompressor;	/* So common code can tell which is which */\
349   int global_state		/* For checking call sequence validity */
350 
351 /* Routines that are to be used by both halves of the library are declared
352  * to receive a pointer to this structure.  There are no actual instances of
353  * jpeg_common_struct, only of jpeg_compress_struct and jpeg_decompress_struct.
354  */
355 struct jpeg_common_struct {
356   jpeg_common_fields;		/* Fields common to both master struct types */
357   /* Additional fields follow in an actual jpeg_compress_struct or
358    * jpeg_decompress_struct.  All three structs must agree on these
359    * initial fields!  (This would be a lot cleaner in C++.)
360    */
361 };
362 
363 typedef struct jpeg_common_struct * j_common_ptr;
364 typedef struct jpeg_compress_struct * j_compress_ptr;
365 typedef struct jpeg_decompress_struct * j_decompress_ptr;
366 
367 
368 /* Master record for a compression instance */
369 
370 struct jpeg_compress_struct {
371   jpeg_common_fields;		/* Fields shared with jpeg_decompress_struct */
372 
373   /* Destination for compressed data */
374   struct jpeg_destination_mgr * dest;
375 
376   /* Description of source image --- these fields must be filled in by
377    * outer application before starting compression.  in_color_space must
378    * be correct before you can even call jpeg_set_defaults().
379    */
380 
381   JDIMENSION image_width;	/* input image width */
382   JDIMENSION image_height;	/* input image height */
383   int input_components;		/* # of color components in input image */
384   J_COLOR_SPACE in_color_space;	/* colorspace of input image */
385 
386   double input_gamma;		/* image gamma of input image */
387 
388   /* Compression parameters --- these fields must be set before calling
389    * jpeg_start_compress().  We recommend calling jpeg_set_defaults() to
390    * initialize everything to reasonable defaults, then changing anything
391    * the application specifically wants to change.  That way you won't get
392    * burnt when new parameters are added.  Also note that there are several
393    * helper routines to simplify changing parameters.
394    */
395 
396   int data_precision;		/* bits of precision in image data */
397 
398   int num_components;		/* # of color components in JPEG image */
399   J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
400 
401   jpeg_component_info * comp_info;
402   /* comp_info[i] describes component that appears i'th in SOF */
403 
404   JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
405   /* ptrs to coefficient quantization tables, or NULL if not defined */
406 
407   JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
408   JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
409   /* ptrs to Huffman coding tables, or NULL if not defined */
410 
411   UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
412   UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
413   UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
414 
415   int num_scans;		/* # of entries in scan_info array */
416   const jpeg_scan_info * scan_info; /* script for multi-scan file, or NULL */
417   /* The default value of scan_info is NULL, which causes a single-scan
418    * sequential JPEG file to be emitted.  To create a multi-scan file,
419    * set num_scans and scan_info to point to an array of scan definitions.
420    */
421 
422   boolean raw_data_in;		/* TRUE=caller supplies downsampled data */
423   boolean arith_code;		/* TRUE=arithmetic coding, FALSE=Huffman */
424   boolean optimize_coding;	/* TRUE=optimize entropy encoding parms */
425   boolean CCIR601_sampling;	/* TRUE=first samples are cosited */
426   int smoothing_factor;		/* 1..100, or 0 for no input smoothing */
427   J_DCT_METHOD dct_method;	/* DCT algorithm selector */
428 
429   /* The restart interval can be specified in absolute MCUs by setting
430    * restart_interval, or in MCU rows by setting restart_in_rows
431    * (in which case the correct restart_interval will be figured
432    * for each scan).
433    */
434   unsigned int restart_interval; /* MCUs per restart, or 0 for no restart */
435   int restart_in_rows;		/* if > 0, MCU rows per restart interval */
436 
437   /* Parameters controlling emission of special markers. */
438 
439   boolean write_JFIF_header;	/* should a JFIF marker be written? */
440   UINT8 JFIF_major_version;	/* What to write for the JFIF version number */
441   UINT8 JFIF_minor_version;
442   /* These three values are not used by the JPEG code, merely copied */
443   /* into the JFIF APP0 marker.  density_unit can be 0 for unknown, */
444   /* 1 for dots/inch, or 2 for dots/cm.  Note that the pixel aspect */
445   /* ratio is defined by X_density/Y_density even when density_unit=0. */
446   UINT8 density_unit;		/* JFIF code for pixel size units */
447   UINT16 X_density;		/* Horizontal pixel density */
448   UINT16 Y_density;		/* Vertical pixel density */
449   boolean write_Adobe_marker;	/* should an Adobe marker be written? */
450 
451   /* State variable: index of next scanline to be written to
452    * jpeg_write_scanlines().  Application may use this to control its
453    * processing loop, e.g., "while (next_scanline < image_height)".
454    */
455 
456   JDIMENSION next_scanline;	/* 0 .. image_height-1  */
457 
458   /* Remaining fields are known throughout compressor, but generally
459    * should not be touched by a surrounding application.
460    */
461 
462   /*
463    * These fields are computed during compression startup
464    */
465   boolean progressive_mode;	/* TRUE if scan script uses progressive mode */
466   int max_h_samp_factor;	/* largest h_samp_factor */
467   int max_v_samp_factor;	/* largest v_samp_factor */
468 
469   JDIMENSION total_iMCU_rows;	/* # of iMCU rows to be input to coef ctlr */
470   /* The coefficient controller receives data in units of MCU rows as defined
471    * for fully interleaved scans (whether the JPEG file is interleaved or not).
472    * There are v_samp_factor * DCTSIZE sample rows of each component in an
473    * "iMCU" (interleaved MCU) row.
474    */
475 
476   /*
477    * These fields are valid during any one scan.
478    * They describe the components and MCUs actually appearing in the scan.
479    */
480   int comps_in_scan;		/* # of JPEG components in this scan */
481   jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
482   /* *cur_comp_info[i] describes component that appears i'th in SOS */
483 
484   JDIMENSION MCUs_per_row;	/* # of MCUs across the image */
485   JDIMENSION MCU_rows_in_scan;	/* # of MCU rows in the image */
486 
487   int blocks_in_MCU;		/* # of DCT blocks per MCU */
488   int MCU_membership[C_MAX_BLOCKS_IN_MCU];
489   /* MCU_membership[i] is index in cur_comp_info of component owning */
490   /* i'th block in an MCU */
491 
492   int Ss, Se, Ah, Al;		/* progressive JPEG parameters for scan */
493 
494   /*
495    * Links to compression subobjects (methods and private variables of modules)
496    */
497   struct jpeg_comp_master * master;
498   struct jpeg_c_main_controller * main;
499   struct jpeg_c_prep_controller * prep;
500   struct jpeg_c_coef_controller * coef;
501   struct jpeg_marker_writer * marker;
502   struct jpeg_color_converter * cconvert;
503   struct jpeg_downsampler * downsample;
504   struct jpeg_forward_dct * fdct;
505   struct jpeg_entropy_encoder * entropy;
506   jpeg_scan_info * script_space; /* workspace for jpeg_simple_progression */
507   int script_space_size;
508 };
509 
510 
511 /* Master record for a decompression instance */
512 
513 struct jpeg_decompress_struct {
514   jpeg_common_fields;		/* Fields shared with jpeg_compress_struct */
515 
516   /* Source of compressed data */
517   struct jpeg_source_mgr * src;
518 
519   /* Basic description of image --- filled in by jpeg_read_header(). */
520   /* Application may inspect these values to decide how to process image. */
521 
522   JDIMENSION image_width;	/* nominal image width (from SOF marker) */
523   JDIMENSION image_height;	/* nominal image height */
524   int num_components;		/* # of color components in JPEG image */
525   J_COLOR_SPACE jpeg_color_space; /* colorspace of JPEG image */
526 
527   /* Decompression processing parameters --- these fields must be set before
528    * calling jpeg_start_decompress().  Note that jpeg_read_header() initializes
529    * them to default values.
530    */
531 
532   J_COLOR_SPACE out_color_space; /* colorspace for output */
533 
534   unsigned int scale_num, scale_denom; /* fraction by which to scale image */
535 
536   double output_gamma;		/* image gamma wanted in output */
537 
538   boolean buffered_image;	/* TRUE=multiple output passes */
539   boolean raw_data_out;		/* TRUE=downsampled data wanted */
540 
541   J_DCT_METHOD dct_method;	/* IDCT algorithm selector */
542   boolean do_fancy_upsampling;	/* TRUE=apply fancy upsampling */
543   boolean do_block_smoothing;	/* TRUE=apply interblock smoothing */
544 
545   boolean quantize_colors;	/* TRUE=colormapped output wanted */
546   /* the following are ignored if not quantize_colors: */
547   J_DITHER_MODE dither_mode;	/* type of color dithering to use */
548   boolean two_pass_quantize;	/* TRUE=use two-pass color quantization */
549   int desired_number_of_colors;	/* max # colors to use in created colormap */
550   /* these are significant only in buffered-image mode: */
551   boolean enable_1pass_quant;	/* enable future use of 1-pass quantizer */
552   boolean enable_external_quant;/* enable future use of external colormap */
553   boolean enable_2pass_quant;	/* enable future use of 2-pass quantizer */
554 
555   /* Description of actual output image that will be returned to application.
556    * These fields are computed by jpeg_start_decompress().
557    * You can also use jpeg_calc_output_dimensions() to determine these values
558    * in advance of calling jpeg_start_decompress().
559    */
560 
561   JDIMENSION output_width;	/* scaled image width */
562   JDIMENSION output_height;	/* scaled image height */
563   int out_color_components;	/* # of color components in out_color_space */
564   int output_components;	/* # of color components returned */
565   /* output_components is 1 (a colormap index) when quantizing colors;
566    * otherwise it equals out_color_components.
567    */
568   int rec_outbuf_height;	/* min recommended height of scanline buffer */
569   /* If the buffer passed to jpeg_read_scanlines() is less than this many rows
570    * high, space and time will be wasted due to unnecessary data copying.
571    * Usually rec_outbuf_height will be 1 or 2, at most 4.
572    */
573 
574   /* When quantizing colors, the output colormap is described by these fields.
575    * The application can supply a colormap by setting colormap non-NULL before
576    * calling jpeg_start_decompress; otherwise a colormap is created during
577    * jpeg_start_decompress or jpeg_start_output.
578    * The map has out_color_components rows and actual_number_of_colors columns.
579    */
580   int actual_number_of_colors;	/* number of entries in use */
581   JSAMPARRAY colormap;		/* The color map as a 2-D pixel array */
582 
583   /* State variables: these variables indicate the progress of decompression.
584    * The application may examine these but must not modify them.
585    */
586 
587   /* Row index of next scanline to be read from jpeg_read_scanlines().
588    * Application may use this to control its processing loop, e.g.,
589    * "while (output_scanline < output_height)".
590    */
591   JDIMENSION output_scanline;	/* 0 .. output_height-1  */
592 
593   /* Current input scan number and number of iMCU rows completed in scan.
594    * These indicate the progress of the decompressor input side.
595    */
596   int input_scan_number;	/* Number of SOS markers seen so far */
597   JDIMENSION input_iMCU_row;	/* Number of iMCU rows completed */
598 
599   /* The "output scan number" is the notional scan being displayed by the
600    * output side.  The decompressor will not allow output scan/row number
601    * to get ahead of input scan/row, but it can fall arbitrarily far behind.
602    */
603   int output_scan_number;	/* Nominal scan number being displayed */
604   JDIMENSION output_iMCU_row;	/* Number of iMCU rows read */
605 
606   /* Current progression status.  coef_bits[c][i] indicates the precision
607    * with which component c's DCT coefficient i (in zigzag order) is known.
608    * It is -1 when no data has yet been received, otherwise it is the point
609    * transform (shift) value for the most recent scan of the coefficient
610    * (thus, 0 at completion of the progression).
611    * This pointer is NULL when reading a non-progressive file.
612    */
613   int (*coef_bits)[DCTSIZE2];	/* -1 or current Al value for each coef */
614 
615   /* Internal JPEG parameters --- the application usually need not look at
616    * these fields.  Note that the decompressor output side may not use
617    * any parameters that can change between scans.
618    */
619 
620   /* Quantization and Huffman tables are carried forward across input
621    * datastreams when processing abbreviated JPEG datastreams.
622    */
623 
624   JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS];
625   /* ptrs to coefficient quantization tables, or NULL if not defined */
626 
627   JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
628   JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
629   /* ptrs to Huffman coding tables, or NULL if not defined */
630 
631   /* These parameters are never carried across datastreams, since they
632    * are given in SOF/SOS markers or defined to be reset by SOI.
633    */
634 
635   int data_precision;		/* bits of precision in image data */
636 
637   jpeg_component_info * comp_info;
638   /* comp_info[i] describes component that appears i'th in SOF */
639 
640   boolean progressive_mode;	/* TRUE if SOFn specifies progressive mode */
641   boolean arith_code;		/* TRUE=arithmetic coding, FALSE=Huffman */
642 
643   UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */
644   UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */
645   UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */
646 
647   unsigned int restart_interval; /* MCUs per restart interval, or 0 for no restart */
648 
649   /* These fields record data obtained from optional markers recognized by
650    * the JPEG library.
651    */
652   boolean saw_JFIF_marker;	/* TRUE iff a JFIF APP0 marker was found */
653   /* Data copied from JFIF marker; only valid if saw_JFIF_marker is TRUE: */
654   UINT8 JFIF_major_version;	/* JFIF version number */
655   UINT8 JFIF_minor_version;
656   UINT8 density_unit;		/* JFIF code for pixel size units */
657   UINT16 X_density;		/* Horizontal pixel density */
658   UINT16 Y_density;		/* Vertical pixel density */
659   boolean saw_Adobe_marker;	/* TRUE iff an Adobe APP14 marker was found */
660   UINT8 Adobe_transform;	/* Color transform code from Adobe marker */
661 
662   boolean CCIR601_sampling;	/* TRUE=first samples are cosited */
663 
664   /* Aside from the specific data retained from APPn markers known to the
665    * library, the uninterpreted contents of any or all APPn and COM markers
666    * can be saved in a list for examination by the application.
667    */
668   jpeg_saved_marker_ptr marker_list; /* Head of list of saved markers */
669 
670   /* Remaining fields are known throughout decompressor, but generally
671    * should not be touched by a surrounding application.
672    */
673 
674   /*
675    * These fields are computed during decompression startup
676    */
677   int max_h_samp_factor;	/* largest h_samp_factor */
678   int max_v_samp_factor;	/* largest v_samp_factor */
679 
680   int min_DCT_scaled_size;	/* smallest DCT_scaled_size of any component */
681 
682   JDIMENSION total_iMCU_rows;	/* # of iMCU rows in image */
683   /* The coefficient controller's input and output progress is measured in
684    * units of "iMCU" (interleaved MCU) rows.  These are the same as MCU rows
685    * in fully interleaved JPEG scans, but are used whether the scan is
686    * interleaved or not.  We define an iMCU row as v_samp_factor DCT block
687    * rows of each component.  Therefore, the IDCT output contains
688    * v_samp_factor*DCT_scaled_size sample rows of a component per iMCU row.
689    */
690 
691   JSAMPLE * sample_range_limit; /* table for fast range-limiting */
692 
693   /*
694    * These fields are valid during any one scan.
695    * They describe the components and MCUs actually appearing in the scan.
696    * Note that the decompressor output side must not use these fields.
697    */
698   int comps_in_scan;		/* # of JPEG components in this scan */
699   jpeg_component_info * cur_comp_info[MAX_COMPS_IN_SCAN];
700   /* *cur_comp_info[i] describes component that appears i'th in SOS */
701 
702   JDIMENSION MCUs_per_row;	/* # of MCUs across the image */
703   JDIMENSION MCU_rows_in_scan;	/* # of MCU rows in the image */
704 
705   int blocks_in_MCU;		/* # of DCT blocks per MCU */
706   int MCU_membership[D_MAX_BLOCKS_IN_MCU];
707   /* MCU_membership[i] is index in cur_comp_info of component owning */
708   /* i'th block in an MCU */
709 
710   int Ss, Se, Ah, Al;		/* progressive JPEG parameters for scan */
711 
712   /* This field is shared between entropy decoder and marker parser.
713    * It is either zero or the code of a JPEG marker that has been
714    * read from the data source, but has not yet been processed.
715    */
716   int unread_marker;
717 
718   /*
719    * Links to decompression subobjects (methods, private variables of modules)
720    */
721   struct jpeg_decomp_master * master;
722   struct jpeg_d_main_controller * main;
723   struct jpeg_d_coef_controller * coef;
724   struct jpeg_d_post_controller * post;
725   struct jpeg_input_controller * inputctl;
726   struct jpeg_marker_reader * marker;
727   struct jpeg_entropy_decoder * entropy;
728   struct jpeg_inverse_dct * idct;
729   struct jpeg_upsampler * upsample;
730   struct jpeg_color_deconverter * cconvert;
731   struct jpeg_color_quantizer * cquantize;
732 };
733 
734 
735 /* "Object" declarations for JPEG modules that may be supplied or called
736  * directly by the surrounding application.
737  * As with all objects in the JPEG library, these structs only define the
738  * publicly visible methods and state variables of a module.  Additional
739  * private fields may exist after the public ones.
740  */
741 
742 
743 /* Error handler object */
744 
745 struct jpeg_error_mgr {
746   /* Error exit handler: does not return to caller */
747   JMETHOD(void, error_exit, (j_common_ptr cinfo));
748   /* Conditionally emit a trace or warning message */
749   JMETHOD(void, emit_message, (j_common_ptr cinfo, int msg_level));
750   /* Routine that actually outputs a trace or error message */
751   JMETHOD(void, output_message, (j_common_ptr cinfo));
752   /* Format a message string for the most recent JPEG error or message */
753   JMETHOD(void, format_message, (j_common_ptr cinfo, char * buffer));
754 #define JMSG_LENGTH_MAX  200	/* recommended size of format_message buffer */
755   /* Reset error state variables at start of a new image */
756   JMETHOD(void, reset_error_mgr, (j_common_ptr cinfo));
757 
758   /* The message ID code and any parameters are saved here.
759    * A message can have one string parameter or up to 8 int parameters.
760    */
761   int msg_code;
762 #define JMSG_STR_PARM_MAX  80
763   union {
764     int i[8];
765     char s[JMSG_STR_PARM_MAX];
766   } msg_parm;
767 
768   /* Standard state variables for error facility */
769 
770   int trace_level;		/* max msg_level that will be displayed */
771 
772   /* For recoverable corrupt-data errors, we emit a warning message,
773    * but keep going unless emit_message chooses to abort.  emit_message
774    * should count warnings in num_warnings.  The surrounding application
775    * can check for bad data by seeing if num_warnings is nonzero at the
776    * end of processing.
777    */
778   long num_warnings;		/* number of corrupt-data warnings */
779 
780   /* These fields point to the table(s) of error message strings.
781    * An application can change the table pointer to switch to a different
782    * message list (typically, to change the language in which errors are
783    * reported).  Some applications may wish to add additional error codes
784    * that will be handled by the JPEG library error mechanism; the second
785    * table pointer is used for this purpose.
786    *
787    * First table includes all errors generated by JPEG library itself.
788    * Error code 0 is reserved for a "no such error string" message.
789    */
790   const char * const * jpeg_message_table; /* Library errors */
791   int last_jpeg_message;    /* Table contains strings 0..last_jpeg_message */
792   /* Second table can be added by application (see cjpeg/djpeg for example).
793    * It contains strings numbered first_addon_message..last_addon_message.
794    */
795   const char * const * addon_message_table; /* Non-library errors */
796   int first_addon_message;	/* code for first string in addon table */
797   int last_addon_message;	/* code for last string in addon table */
798 };
799 
800 
801 /* Progress monitor object */
802 
803 struct jpeg_progress_mgr {
804   JMETHOD(void, progress_monitor, (j_common_ptr cinfo));
805 
806   long pass_counter;		/* work units completed in this pass */
807   long pass_limit;		/* total number of work units in this pass */
808   int completed_passes;		/* passes completed so far */
809   int total_passes;		/* total number of passes expected */
810 };
811 
812 
813 /* Data destination object for compression */
814 
815 struct jpeg_destination_mgr {
816   JOCTET * next_output_byte;	/* => next byte to write in buffer */
817   size_t free_in_buffer;	/* # of byte spaces remaining in buffer */
818 
819   JMETHOD(void, init_destination, (j_compress_ptr cinfo));
820   JMETHOD(boolean, empty_output_buffer, (j_compress_ptr cinfo));
821   JMETHOD(void, term_destination, (j_compress_ptr cinfo));
822 };
823 
824 
825 /* Data source object for decompression */
826 
827 struct jpeg_source_mgr {
828   const JOCTET * next_input_byte; /* => next byte to read from buffer */
829   size_t bytes_in_buffer;	/* # of bytes remaining in buffer */
830 
831   JMETHOD(void, init_source, (j_decompress_ptr cinfo));
832   JMETHOD(boolean, fill_input_buffer, (j_decompress_ptr cinfo));
833   JMETHOD(void, skip_input_data, (j_decompress_ptr cinfo, long num_bytes));
834   JMETHOD(boolean, resync_to_restart, (j_decompress_ptr cinfo, int desired));
835   JMETHOD(void, term_source, (j_decompress_ptr cinfo));
836 };
837 
838 
839 /* Memory manager object.
840  * Allocates "small" objects (a few K total), "large" objects (tens of K),
841  * and "really big" objects (virtual arrays with backing store if needed).
842  * The memory manager does not allow individual objects to be freed; rather,
843  * each created object is assigned to a pool, and whole pools can be freed
844  * at once.  This is faster and more convenient than remembering exactly what
845  * to free, especially where malloc()/free() are not too speedy.
846  * NB: alloc routines never return NULL.  They exit to error_exit if not
847  * successful.
848  */
849 
850 #define JPOOL_PERMANENT	0	/* lasts until master record is destroyed */
851 #define JPOOL_IMAGE	1	/* lasts until done with image/datastream */
852 #define JPOOL_NUMPOOLS	2
853 
854 typedef struct jvirt_sarray_control * jvirt_sarray_ptr;
855 typedef struct jvirt_barray_control * jvirt_barray_ptr;
856 
857 
858 struct jpeg_memory_mgr {
859   /* Method pointers */
860   JMETHOD(void *, alloc_small, (j_common_ptr cinfo, int pool_id,
861 				size_t sizeofobject));
862   JMETHOD(void  *, alloc_large, (j_common_ptr cinfo, int pool_id,
863 				     size_t sizeofobject));
864   JMETHOD(JSAMPARRAY, alloc_sarray, (j_common_ptr cinfo, int pool_id,
865 				     JDIMENSION samplesperrow,
866 				     JDIMENSION numrows));
867   JMETHOD(JBLOCKARRAY, alloc_barray, (j_common_ptr cinfo, int pool_id,
868 				      JDIMENSION blocksperrow,
869 				      JDIMENSION numrows));
870   JMETHOD(jvirt_sarray_ptr, request_virt_sarray, (j_common_ptr cinfo,
871 						  int pool_id,
872 						  boolean pre_zero,
873 						  JDIMENSION samplesperrow,
874 						  JDIMENSION numrows,
875 						  JDIMENSION maxaccess));
876   JMETHOD(jvirt_barray_ptr, request_virt_barray, (j_common_ptr cinfo,
877 						  int pool_id,
878 						  boolean pre_zero,
879 						  JDIMENSION blocksperrow,
880 						  JDIMENSION numrows,
881 						  JDIMENSION maxaccess));
882   JMETHOD(void, realize_virt_arrays, (j_common_ptr cinfo));
883   JMETHOD(JSAMPARRAY, access_virt_sarray, (j_common_ptr cinfo,
884 					   jvirt_sarray_ptr ptr,
885 					   JDIMENSION start_row,
886 					   JDIMENSION num_rows,
887 					   boolean writable));
888   JMETHOD(JBLOCKARRAY, access_virt_barray, (j_common_ptr cinfo,
889 					    jvirt_barray_ptr ptr,
890 					    JDIMENSION start_row,
891 					    JDIMENSION num_rows,
892 					    boolean writable));
893   JMETHOD(void, free_pool, (j_common_ptr cinfo, int pool_id));
894   JMETHOD(void, self_destruct, (j_common_ptr cinfo));
895 
896   /* Limit on memory allocation for this JPEG object.  (Note that this is
897    * merely advisory, not a guaranteed maximum; it only affects the space
898    * used for virtual-array buffers.)  May be changed by outer application
899    * after creating the JPEG object.
900    */
901   long max_memory_to_use;
902 
903   /* Maximum allocation request accepted by alloc_large. */
904   long max_alloc_chunk;
905 };
906 
907 
908 /* Routine signature for application-supplied marker processing methods.
909  * Need not pass marker code since it is stored in cinfo->unread_marker.
910  */
911 typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo));
912 
913 
914 /* Declarations for routines called by application.
915  * The JPP macro hides prototype parameters from compilers that can't cope.
916  * Note JPP requires double parentheses.
917  */
918 
919 #ifdef HAVE_PROTOTYPES
920 #define JPP(arglist)	arglist
921 #else
922 #define JPP(arglist)	()
923 #endif
924 
925 
926 /* Short forms of external names for systems with brain-damaged linkers.
927  * We shorten external names to be unique in the first six letters, which
928  * is good enough for all known systems.
929  * (If your compiler itself needs names to be unique in less than 15
930  * characters, you are out of luck.  Get a better compiler.)
931  */
932 
933 #ifdef NEED_SHORT_EXTERNAL_NAMES
934 #define jpeg_std_error		jStdError
935 #define jpeg_CreateCompress	jCreaCompress
936 #define jpeg_CreateDecompress	jCreaDecompress
937 #define jpeg_destroy_compress	jDestCompress
938 #define jpeg_destroy_decompress	jDestDecompress
939 #define jpeg_stdio_dest		jStdDest
940 #define jpeg_stdio_src		jStdSrc
941 #define jpeg_set_defaults	jSetDefaults
942 #define jpeg_set_colorspace	jSetColorspace
943 #define jpeg_default_colorspace	jDefColorspace
944 #define jpeg_set_quality	jSetQuality
945 #define jpeg_set_linear_quality	jSetLQuality
946 #define jpeg_add_quant_table	jAddQuantTable
947 #define jpeg_quality_scaling	jQualityScaling
948 #define jpeg_simple_progression	jSimProgress
949 #define jpeg_suppress_tables	jSuppressTables
950 #define jpeg_alloc_quant_table	jAlcQTable
951 #define jpeg_alloc_huff_table	jAlcHTable
952 #define jpeg_start_compress	jStrtCompress
953 #define jpeg_write_scanlines	jWrtScanlines
954 #define jpeg_finish_compress	jFinCompress
955 #define jpeg_write_raw_data	jWrtRawData
956 #define jpeg_write_marker	jWrtMarker
957 #define jpeg_write_m_header	jWrtMHeader
958 #define jpeg_write_m_byte	jWrtMByte
959 #define jpeg_write_tables	jWrtTables
960 #define jpeg_read_header	jReadHeader
961 #define jpeg_start_decompress	jStrtDecompress
962 #define jpeg_read_scanlines	jReadScanlines
963 #define jpeg_finish_decompress	jFinDecompress
964 #define jpeg_read_raw_data	jReadRawData
965 #define jpeg_has_multiple_scans	jHasMultScn
966 #define jpeg_start_output	jStrtOutput
967 #define jpeg_finish_output	jFinOutput
968 #define jpeg_input_complete	jInComplete
969 #define jpeg_new_colormap	jNewCMap
970 #define jpeg_consume_input	jConsumeInput
971 #define jpeg_calc_output_dimensions	jCalcDimensions
972 #define jpeg_save_markers	jSaveMarkers
973 #define jpeg_set_marker_processor	jSetMarker
974 #define jpeg_read_coefficients	jReadCoefs
975 #define jpeg_write_coefficients	jWrtCoefs
976 #define jpeg_copy_critical_parameters	jCopyCrit
977 #define jpeg_abort_compress	jAbrtCompress
978 #define jpeg_abort_decompress	jAbrtDecompress
979 #define jpeg_abort		jAbort
980 #define jpeg_destroy		jDestroy
981 #define jpeg_resync_to_restart	jResyncRestart
982 #endif /* NEED_SHORT_EXTERNAL_NAMES */
983 
984 
985 /* Default error-management setup */
986 EXTERN(struct jpeg_error_mgr *) jpeg_std_error
987 	JPP((struct jpeg_error_mgr * err));
988 
989 /* Initialization of JPEG compression objects.
990  * jpeg_create_compress() and jpeg_create_decompress() are the exported
991  * names that applications should call.  These expand to calls on
992  * jpeg_CreateCompress and jpeg_CreateDecompress with additional information
993  * passed for version mismatch checking.
994  * NB: you must set up the error-manager BEFORE calling jpeg_create_xxx.
995  */
996 #define jpeg_create_compress(cinfo) \
997     jpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, \
998 			(size_t) sizeof(struct jpeg_compress_struct))
999 #define jpeg_create_decompress(cinfo) \
1000     jpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, \
1001 			  (size_t) sizeof(struct jpeg_decompress_struct))
1002 EXTERN(void) jpeg_CreateCompress JPP((j_compress_ptr cinfo,
1003 				      int version, size_t structsize));
1004 EXTERN(void) jpeg_CreateDecompress JPP((j_decompress_ptr cinfo,
1005 					int version, size_t structsize));
1006 /* Destruction of JPEG compression objects */
1007 EXTERN(void) jpeg_destroy_compress JPP((j_compress_ptr cinfo));
1008 EXTERN(void) jpeg_destroy_decompress JPP((j_decompress_ptr cinfo));
1009 
1010 #if 0
1011 /* Standard data source and destination managers: stdio streams. */
1012 /* Caller is responsible for opening the file before and closing after. */
1013 EXTERN(void) jpeg_stdio_dest JPP((j_compress_ptr cinfo, FXSYS_FILE * outfile));
1014 EXTERN(void) jpeg_stdio_src JPP((j_decompress_ptr cinfo, FXSYS_FILE * infile));
1015 #endif
1016 
1017 /* Default parameter setup for compression */
1018 EXTERN(void) jpeg_set_defaults JPP((j_compress_ptr cinfo));
1019 /* Compression parameter setup aids */
1020 EXTERN(void) jpeg_set_colorspace JPP((j_compress_ptr cinfo,
1021 				      J_COLOR_SPACE colorspace));
1022 EXTERN(void) jpeg_default_colorspace JPP((j_compress_ptr cinfo));
1023 EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality,
1024 				   boolean force_baseline));
1025 EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo,
1026 					  int scale_factor,
1027 					  boolean force_baseline));
1028 EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl,
1029 				       const unsigned int *basic_table,
1030 				       int scale_factor,
1031 				       boolean force_baseline));
1032 EXTERN(int) jpeg_quality_scaling JPP((int quality));
1033 EXTERN(void) jpeg_simple_progression JPP((j_compress_ptr cinfo));
1034 EXTERN(void) jpeg_suppress_tables JPP((j_compress_ptr cinfo,
1035 				       boolean suppress));
1036 EXTERN(JQUANT_TBL *) jpeg_alloc_quant_table JPP((j_common_ptr cinfo));
1037 EXTERN(JHUFF_TBL *) jpeg_alloc_huff_table JPP((j_common_ptr cinfo));
1038 
1039 /* Main entry points for compression */
1040 EXTERN(void) jpeg_start_compress JPP((j_compress_ptr cinfo,
1041 				      boolean write_all_tables));
1042 EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo,
1043 					     JSAMPARRAY scanlines,
1044 					     JDIMENSION num_lines));
1045 EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo));
1046 
1047 /* Replaces jpeg_write_scanlines when writing raw downsampled data. */
1048 EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo,
1049 					    JSAMPIMAGE data,
1050 					    JDIMENSION num_lines));
1051 
1052 /* Write a special marker.  See libjpeg.doc concerning safe usage. */
1053 EXTERN(void) jpeg_write_marker
1054 	JPP((j_compress_ptr cinfo, int marker,
1055 	     const JOCTET * dataptr, unsigned int datalen));
1056 /* Same, but piecemeal. */
1057 EXTERN(void) jpeg_write_m_header
1058 	JPP((j_compress_ptr cinfo, int marker, unsigned int datalen));
1059 EXTERN(void) jpeg_write_m_byte
1060 	JPP((j_compress_ptr cinfo, int val));
1061 
1062 /* Alternate compression function: just write an abbreviated table file */
1063 EXTERN(void) jpeg_write_tables JPP((j_compress_ptr cinfo));
1064 
1065 /* Decompression startup: read start of JPEG datastream to see what's there */
1066 EXTERN(int) jpeg_read_header JPP((j_decompress_ptr cinfo,
1067 				  boolean require_image));
1068 /* Return value is one of: */
1069 #define JPEG_SUSPENDED		0 /* Suspended due to lack of input data */
1070 #define JPEG_HEADER_OK		1 /* Found valid image datastream */
1071 #define JPEG_HEADER_TABLES_ONLY	2 /* Found valid table-specs-only datastream */
1072 /* If you pass require_image = TRUE (normal case), you need not check for
1073  * a TABLES_ONLY return code; an abbreviated file will cause an error exit.
1074  * JPEG_SUSPENDED is only possible if you use a data source module that can
1075  * give a suspension return (the stdio source module doesn't).
1076  */
1077 
1078 /* Main entry points for decompression */
1079 EXTERN(boolean) jpeg_start_decompress JPP((j_decompress_ptr cinfo));
1080 EXTERN(JDIMENSION) jpeg_read_scanlines JPP((j_decompress_ptr cinfo,
1081 					    JSAMPARRAY scanlines,
1082 					    JDIMENSION max_lines));
1083 EXTERN(boolean) jpeg_finish_decompress JPP((j_decompress_ptr cinfo));
1084 
1085 /* Replaces jpeg_read_scanlines when reading raw downsampled data. */
1086 EXTERN(JDIMENSION) jpeg_read_raw_data JPP((j_decompress_ptr cinfo,
1087 					   JSAMPIMAGE data,
1088 					   JDIMENSION max_lines));
1089 
1090 /* Additional entry points for buffered-image mode. */
1091 EXTERN(boolean) jpeg_has_multiple_scans JPP((j_decompress_ptr cinfo));
1092 EXTERN(boolean) jpeg_start_output JPP((j_decompress_ptr cinfo,
1093 				       int scan_number));
1094 EXTERN(boolean) jpeg_finish_output JPP((j_decompress_ptr cinfo));
1095 EXTERN(boolean) jpeg_input_complete JPP((j_decompress_ptr cinfo));
1096 EXTERN(void) jpeg_new_colormap JPP((j_decompress_ptr cinfo));
1097 EXTERN(int) jpeg_consume_input JPP((j_decompress_ptr cinfo));
1098 /* Return value is one of: */
1099 /* #define JPEG_SUSPENDED	0    Suspended due to lack of input data */
1100 #define JPEG_REACHED_SOS	1 /* Reached start of new scan */
1101 #define JPEG_REACHED_EOI	2 /* Reached end of image */
1102 #define JPEG_ROW_COMPLETED	3 /* Completed one iMCU row */
1103 #define JPEG_SCAN_COMPLETED	4 /* Completed last iMCU row of a scan */
1104 
1105 /* Precalculate output dimensions for current decompression parameters. */
1106 EXTERN(void) jpeg_calc_output_dimensions JPP((j_decompress_ptr cinfo));
1107 
1108 /* Control saving of COM and APPn markers into marker_list. */
1109 EXTERN(void) jpeg_save_markers
1110 	JPP((j_decompress_ptr cinfo, int marker_code,
1111 	     unsigned int length_limit));
1112 
1113 /* Install a special processing method for COM or APPn markers. */
1114 EXTERN(void) jpeg_set_marker_processor
1115 	JPP((j_decompress_ptr cinfo, int marker_code,
1116 	     jpeg_marker_parser_method routine));
1117 
1118 /* Read or write raw DCT coefficients --- useful for lossless transcoding. */
1119 EXTERN(jvirt_barray_ptr *) jpeg_read_coefficients JPP((j_decompress_ptr cinfo));
1120 EXTERN(void) jpeg_write_coefficients JPP((j_compress_ptr cinfo,
1121 					  jvirt_barray_ptr * coef_arrays));
1122 EXTERN(void) jpeg_copy_critical_parameters JPP((j_decompress_ptr srcinfo,
1123 						j_compress_ptr dstinfo));
1124 
1125 /* If you choose to abort compression or decompression before completing
1126  * jpeg_finish_(de)compress, then you need to clean up to release memory,
1127  * temporary files, etc.  You can just call jpeg_destroy_(de)compress
1128  * if you're done with the JPEG object, but if you want to clean it up and
1129  * reuse it, call this:
1130  */
1131 EXTERN(void) jpeg_abort_compress JPP((j_compress_ptr cinfo));
1132 EXTERN(void) jpeg_abort_decompress JPP((j_decompress_ptr cinfo));
1133 
1134 /* Generic versions of jpeg_abort and jpeg_destroy that work on either
1135  * flavor of JPEG object.  These may be more convenient in some places.
1136  */
1137 EXTERN(void) jpeg_abort JPP((j_common_ptr cinfo));
1138 EXTERN(void) jpeg_destroy JPP((j_common_ptr cinfo));
1139 
1140 /* Default restart-marker-resync procedure for use by data source modules */
1141 EXTERN(boolean) jpeg_resync_to_restart JPP((j_decompress_ptr cinfo,
1142 					    int desired));
1143 
1144 
1145 /* These marker codes are exported since applications and data source modules
1146  * are likely to want to use them.
1147  */
1148 
1149 #define JPEG_RST0	0xD0	/* RST0 marker code */
1150 #define JPEG_EOI	0xD9	/* EOI marker code */
1151 #define JPEG_APP0	0xE0	/* APP0 marker code */
1152 #define JPEG_COM	0xFE	/* COM marker code */
1153 
1154 
1155 /* If we have a brain-damaged compiler that emits warnings (or worse, errors)
1156  * for structure definitions that are never filled in, keep it quiet by
1157  * supplying dummy definitions for the various substructures.
1158  */
1159 
1160 #ifdef INCOMPLETE_TYPES_BROKEN
1161 #ifndef JPEG_INTERNALS		/* will be defined in jpegint.h */
1162 struct jvirt_sarray_control { long dummy; };
1163 struct jvirt_barray_control { long dummy; };
1164 struct jpeg_comp_master { long dummy; };
1165 struct jpeg_c_main_controller { long dummy; };
1166 struct jpeg_c_prep_controller { long dummy; };
1167 struct jpeg_c_coef_controller { long dummy; };
1168 struct jpeg_marker_writer { long dummy; };
1169 struct jpeg_color_converter { long dummy; };
1170 struct jpeg_downsampler { long dummy; };
1171 struct jpeg_forward_dct { long dummy; };
1172 struct jpeg_entropy_encoder { long dummy; };
1173 struct jpeg_decomp_master { long dummy; };
1174 struct jpeg_d_main_controller { long dummy; };
1175 struct jpeg_d_coef_controller { long dummy; };
1176 struct jpeg_d_post_controller { long dummy; };
1177 struct jpeg_input_controller { long dummy; };
1178 struct jpeg_marker_reader { long dummy; };
1179 struct jpeg_entropy_decoder { long dummy; };
1180 struct jpeg_inverse_dct { long dummy; };
1181 struct jpeg_upsampler { long dummy; };
1182 struct jpeg_color_deconverter { long dummy; };
1183 struct jpeg_color_quantizer { long dummy; };
1184 #endif /* JPEG_INTERNALS */
1185 #endif /* INCOMPLETE_TYPES_BROKEN */
1186 
1187 
1188 /*
1189  * The JPEG library modules define JPEG_INTERNALS before including this file.
1190  * The internal structure declarations are read only when that is true.
1191  * Applications using the library should not include jpegint.h, but may wish
1192  * to include jerror.h.
1193  */
1194 
1195 #ifdef JPEG_INTERNALS
1196 #include "jpegint.h"		/* fetch private declarations */
1197 #include "jerror.h"		/* fetch error codes too */
1198 #endif
1199 
1200 #endif /* JPEGLIB_H */
1201