1 /* 2 * jpegint.h 3 * 4 * Copyright (C) 1991-1997, Thomas G. Lane. 5 * Modified 1997-2019 by Guido Vollbeding. 6 * This file is part of the Independent JPEG Group's software. 7 * For conditions of distribution and use, see the accompanying README file. 8 * 9 * This file provides common declarations for the various JPEG modules. 10 * These declarations are considered internal to the JPEG library; most 11 * applications using the library shouldn't need to include this file. 12 */ 13 14 15 /* Declarations for both compression & decompression */ 16 17 typedef enum { /* Operating modes for buffer controllers */ 18 JBUF_PASS_THRU, /* Plain stripwise operation */ 19 /* Remaining modes require a full-image buffer to have been created */ 20 JBUF_SAVE_SOURCE, /* Run source subobject only, save output */ 21 JBUF_CRANK_DEST, /* Run dest subobject only, using saved data */ 22 JBUF_SAVE_AND_PASS /* Run both subobjects, save output */ 23 } J_BUF_MODE; 24 25 /* Values of global_state field (jdapi.c has some dependencies on ordering!) */ 26 #define CSTATE_START 100 /* after create_compress */ 27 #define CSTATE_SCANNING 101 /* start_compress done, write_scanlines OK */ 28 #define CSTATE_RAW_OK 102 /* start_compress done, write_raw_data OK */ 29 #define CSTATE_WRCOEFS 103 /* jpeg_write_coefficients done */ 30 #define DSTATE_START 200 /* after create_decompress */ 31 #define DSTATE_INHEADER 201 /* reading header markers, no SOS yet */ 32 #define DSTATE_READY 202 /* found SOS, ready for start_decompress */ 33 #define DSTATE_PRELOAD 203 /* reading multiscan file in start_decompress*/ 34 #define DSTATE_PRESCAN 204 /* performing dummy pass for 2-pass quant */ 35 #define DSTATE_SCANNING 205 /* start_decompress done, read_scanlines OK */ 36 #define DSTATE_RAW_OK 206 /* start_decompress done, read_raw_data OK */ 37 #define DSTATE_BUFIMAGE 207 /* expecting jpeg_start_output */ 38 #define DSTATE_BUFPOST 208 /* looking for SOS/EOI in jpeg_finish_output */ 39 #define DSTATE_RDCOEFS 209 /* reading file in jpeg_read_coefficients */ 40 #define DSTATE_STOPPING 210 /* looking for EOI in jpeg_finish_decompress */ 41 42 43 /* Declarations for compression modules */ 44 45 /* Master control module */ 46 struct jpeg_comp_master { 47 JMETHOD(void, prepare_for_pass, (j_compress_ptr cinfo)); 48 JMETHOD(void, pass_startup, (j_compress_ptr cinfo)); 49 JMETHOD(void, finish_pass, (j_compress_ptr cinfo)); 50 51 /* State variables made visible to other modules */ 52 boolean call_pass_startup; /* True if pass_startup must be called */ 53 boolean is_last_pass; /* True during last pass */ 54 }; 55 56 /* Main buffer control (downsampled-data buffer) */ 57 struct jpeg_c_main_controller { 58 JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); 59 JMETHOD(void, process_data, (j_compress_ptr cinfo, 60 JSAMPARRAY input_buf, JDIMENSION *in_row_ctr, 61 JDIMENSION in_rows_avail)); 62 }; 63 64 /* Compression preprocessing (downsampling input buffer control) */ 65 struct jpeg_c_prep_controller { 66 JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); 67 JMETHOD(void, pre_process_data, (j_compress_ptr cinfo, 68 JSAMPARRAY input_buf, 69 JDIMENSION *in_row_ctr, 70 JDIMENSION in_rows_avail, 71 JSAMPIMAGE output_buf, 72 JDIMENSION *out_row_group_ctr, 73 JDIMENSION out_row_groups_avail)); 74 }; 75 76 /* Coefficient buffer control */ 77 struct jpeg_c_coef_controller { 78 JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode)); 79 JMETHOD(boolean, compress_data, (j_compress_ptr cinfo, 80 JSAMPIMAGE input_buf)); 81 }; 82 83 /* Colorspace conversion */ 84 struct jpeg_color_converter { 85 JMETHOD(void, start_pass, (j_compress_ptr cinfo)); 86 JMETHOD(void, color_convert, (j_compress_ptr cinfo, 87 JSAMPARRAY input_buf, JSAMPIMAGE output_buf, 88 JDIMENSION output_row, int num_rows)); 89 }; 90 91 /* Downsampling */ 92 struct jpeg_downsampler { 93 JMETHOD(void, start_pass, (j_compress_ptr cinfo)); 94 JMETHOD(void, downsample, (j_compress_ptr cinfo, 95 JSAMPIMAGE input_buf, JDIMENSION in_row_index, 96 JSAMPIMAGE output_buf, 97 JDIMENSION out_row_group_index)); 98 99 boolean need_context_rows; /* TRUE if need rows above & below */ 100 }; 101 102 /* Forward DCT (also controls coefficient quantization) */ 103 typedef JMETHOD(void, forward_DCT_ptr, 104 (j_compress_ptr cinfo, jpeg_component_info * compptr, 105 JSAMPARRAY sample_data, JBLOCKROW coef_blocks, 106 JDIMENSION start_row, JDIMENSION start_col, 107 JDIMENSION num_blocks)); 108 109 struct jpeg_forward_dct { 110 JMETHOD(void, start_pass, (j_compress_ptr cinfo)); 111 /* It is useful to allow each component to have a separate FDCT method. */ 112 forward_DCT_ptr forward_DCT[MAX_COMPONENTS]; 113 }; 114 115 /* Entropy encoding */ 116 struct jpeg_entropy_encoder { 117 JMETHOD(void, start_pass, (j_compress_ptr cinfo, boolean gather_statistics)); 118 JMETHOD(boolean, encode_mcu, (j_compress_ptr cinfo, JBLOCKROW *MCU_data)); 119 JMETHOD(void, finish_pass, (j_compress_ptr cinfo)); 120 }; 121 122 /* Marker writing */ 123 struct jpeg_marker_writer { 124 JMETHOD(void, write_file_header, (j_compress_ptr cinfo)); 125 JMETHOD(void, write_frame_header, (j_compress_ptr cinfo)); 126 JMETHOD(void, write_scan_header, (j_compress_ptr cinfo)); 127 JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo)); 128 JMETHOD(void, write_tables_only, (j_compress_ptr cinfo)); 129 /* These routines are exported to allow insertion of extra markers */ 130 /* Probably only COM and APPn markers should be written this way */ 131 JMETHOD(void, write_marker_header, (j_compress_ptr cinfo, int marker, 132 unsigned int datalen)); 133 JMETHOD(void, write_marker_byte, (j_compress_ptr cinfo, int val)); 134 }; 135 136 137 /* Declarations for decompression modules */ 138 139 /* Master control module */ 140 struct jpeg_decomp_master { 141 JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo)); 142 JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo)); 143 144 /* State variables made visible to other modules */ 145 boolean is_dummy_pass; /* True during 1st pass for 2-pass quant */ 146 }; 147 148 /* Input control module */ 149 struct jpeg_input_controller { 150 JMETHOD(int, consume_input, (j_decompress_ptr cinfo)); 151 JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo)); 152 JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo)); 153 JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo)); 154 155 /* State variables made visible to other modules */ 156 boolean has_multiple_scans; /* True if file has multiple scans */ 157 boolean eoi_reached; /* True when EOI has been consumed */ 158 }; 159 160 /* Main buffer control (downsampled-data buffer) */ 161 struct jpeg_d_main_controller { 162 JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); 163 JMETHOD(void, process_data, (j_decompress_ptr cinfo, 164 JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, 165 JDIMENSION out_rows_avail)); 166 }; 167 168 /* Coefficient buffer control */ 169 struct jpeg_d_coef_controller { 170 JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo)); 171 JMETHOD(int, consume_data, (j_decompress_ptr cinfo)); 172 JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo)); 173 JMETHOD(int, decompress_data, (j_decompress_ptr cinfo, 174 JSAMPIMAGE output_buf)); 175 /* Pointer to array of coefficient virtual arrays, or NULL if none */ 176 jvirt_barray_ptr *coef_arrays; 177 }; 178 179 /* Decompression postprocessing (color quantization buffer control) */ 180 struct jpeg_d_post_controller { 181 JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); 182 JMETHOD(void, post_process_data, (j_decompress_ptr cinfo, 183 JSAMPIMAGE input_buf, 184 JDIMENSION *in_row_group_ctr, 185 JDIMENSION in_row_groups_avail, 186 JSAMPARRAY output_buf, 187 JDIMENSION *out_row_ctr, 188 JDIMENSION out_rows_avail)); 189 }; 190 191 /* Marker reading & parsing */ 192 struct jpeg_marker_reader { 193 JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo)); 194 /* Read markers until SOS or EOI. 195 * Returns same codes as are defined for jpeg_consume_input: 196 * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. 197 */ 198 JMETHOD(int, read_markers, (j_decompress_ptr cinfo)); 199 /* Read a restart marker --- exported for use by entropy decoder only */ 200 jpeg_marker_parser_method read_restart_marker; 201 202 /* State of marker reader --- nominally internal, but applications 203 * supplying COM or APPn handlers might like to know the state. 204 */ 205 boolean saw_SOI; /* found SOI? */ 206 boolean saw_SOF; /* found SOF? */ 207 int next_restart_num; /* next restart number expected (0-7) */ 208 unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */ 209 }; 210 211 /* Entropy decoding */ 212 struct jpeg_entropy_decoder { 213 JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); 214 JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo, JBLOCKROW *MCU_data)); 215 JMETHOD(void, finish_pass, (j_decompress_ptr cinfo)); 216 }; 217 218 /* Inverse DCT (also performs dequantization) */ 219 typedef JMETHOD(void, inverse_DCT_method_ptr, 220 (j_decompress_ptr cinfo, jpeg_component_info * compptr, 221 JCOEFPTR coef_block, 222 JSAMPARRAY output_buf, JDIMENSION output_col)); 223 224 struct jpeg_inverse_dct { 225 JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); 226 /* It is useful to allow each component to have a separate IDCT method. */ 227 inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS]; 228 }; 229 230 /* Upsampling (note that upsampler must also call color converter) */ 231 struct jpeg_upsampler { 232 JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); 233 JMETHOD(void, upsample, (j_decompress_ptr cinfo, 234 JSAMPIMAGE input_buf, 235 JDIMENSION *in_row_group_ctr, 236 JDIMENSION in_row_groups_avail, 237 JSAMPARRAY output_buf, 238 JDIMENSION *out_row_ctr, 239 JDIMENSION out_rows_avail)); 240 241 boolean need_context_rows; /* TRUE if need rows above & below */ 242 }; 243 244 /* Colorspace conversion */ 245 struct jpeg_color_deconverter { 246 JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); 247 JMETHOD(void, color_convert, (j_decompress_ptr cinfo, 248 JSAMPIMAGE input_buf, JDIMENSION input_row, 249 JSAMPARRAY output_buf, int num_rows)); 250 }; 251 252 /* Color quantization or color precision reduction */ 253 struct jpeg_color_quantizer { 254 JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan)); 255 JMETHOD(void, color_quantize, (j_decompress_ptr cinfo, 256 JSAMPARRAY input_buf, JSAMPARRAY output_buf, 257 int num_rows)); 258 JMETHOD(void, finish_pass, (j_decompress_ptr cinfo)); 259 JMETHOD(void, new_color_map, (j_decompress_ptr cinfo)); 260 }; 261 262 263 /* Definition of range extension bits for decompression processes. 264 * See the comments with prepare_range_limit_table (in jdmaster.c) 265 * for more info. 266 * The recommended default value for normal applications is 2. 267 * Applications with special requirements may use a different value. 268 * For example, Ghostscript wants to use 3 for proper handling of 269 * wacky images with oversize coefficient values. 270 */ 271 272 #define RANGE_BITS 2 273 #define RANGE_CENTER (CENTERJSAMPLE << RANGE_BITS) 274 275 276 /* Miscellaneous useful macros */ 277 278 #undef MAX 279 #define MAX(a,b) ((a) > (b) ? (a) : (b)) 280 #undef MIN 281 #define MIN(a,b) ((a) < (b) ? (a) : (b)) 282 283 284 /* We assume that right shift corresponds to signed division by 2 with 285 * rounding towards minus infinity. This is correct for typical "arithmetic 286 * shift" instructions that shift in copies of the sign bit. But some 287 * C compilers implement >> with an unsigned shift. For these machines you 288 * must define RIGHT_SHIFT_IS_UNSIGNED. 289 * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity. 290 * It is only applied with constant shift counts. SHIFT_TEMPS must be 291 * included in the variables of any routine using RIGHT_SHIFT. 292 */ 293 294 #ifdef RIGHT_SHIFT_IS_UNSIGNED 295 #define SHIFT_TEMPS INT32 shift_temp; 296 #define RIGHT_SHIFT(x,shft) \ 297 ((shift_temp = (x)) < 0 ? \ 298 (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \ 299 (shift_temp >> (shft))) 300 #else 301 #define SHIFT_TEMPS 302 #define RIGHT_SHIFT(x,shft) ((x) >> (shft)) 303 #endif 304 305 /* Descale and correctly round an INT32 value that's scaled by N bits. 306 * We assume RIGHT_SHIFT rounds towards minus infinity, so adding 307 * the fudge factor is correct for either sign of X. 308 */ 309 310 #define DESCALE(x,n) RIGHT_SHIFT((x) + ((INT32) 1 << ((n)-1)), n) 311 312 313 /* Short forms of external names for systems with brain-damaged linkers. */ 314 315 #ifdef NEED_SHORT_EXTERNAL_NAMES 316 #define jinit_compress_master jICompress 317 #define jinit_c_master_control jICMaster 318 #define jinit_c_main_controller jICMainC 319 #define jinit_c_prep_controller jICPrepC 320 #define jinit_c_coef_controller jICCoefC 321 #define jinit_color_converter jICColor 322 #define jinit_downsampler jIDownsampler 323 #define jinit_forward_dct jIFDCT 324 #define jinit_huff_encoder jIHEncoder 325 #define jinit_arith_encoder jIAEncoder 326 #define jinit_marker_writer jIMWriter 327 #define jinit_master_decompress jIDMaster 328 #define jinit_d_main_controller jIDMainC 329 #define jinit_d_coef_controller jIDCoefC 330 #define jinit_d_post_controller jIDPostC 331 #define jinit_input_controller jIInCtlr 332 #define jinit_marker_reader jIMReader 333 #define jinit_huff_decoder jIHDecoder 334 #define jinit_arith_decoder jIADecoder 335 #define jinit_inverse_dct jIIDCT 336 #define jinit_upsampler jIUpsampler 337 #define jinit_color_deconverter jIDColor 338 #define jinit_1pass_quantizer jI1Quant 339 #define jinit_2pass_quantizer jI2Quant 340 #define jinit_merged_upsampler jIMUpsampler 341 #define jinit_memory_mgr jIMemMgr 342 #define jdiv_round_up jDivRound 343 #define jround_up jRound 344 #define jzero_far jZeroFar 345 #define jcopy_sample_rows jCopySamples 346 #define jcopy_block_row jCopyBlocks 347 #define jpeg_zigzag_order jZIGTable 348 #define jpeg_natural_order jZAGTable 349 #define jpeg_natural_order7 jZAG7Table 350 #define jpeg_natural_order6 jZAG6Table 351 #define jpeg_natural_order5 jZAG5Table 352 #define jpeg_natural_order4 jZAG4Table 353 #define jpeg_natural_order3 jZAG3Table 354 #define jpeg_natural_order2 jZAG2Table 355 #define jpeg_aritab jAriTab 356 #endif /* NEED_SHORT_EXTERNAL_NAMES */ 357 358 359 /* On normal machines we can apply MEMCOPY() and MEMZERO() to sample arrays 360 * and coefficient-block arrays. This won't work on 80x86 because the arrays 361 * are FAR and we're assuming a small-pointer memory model. However, some 362 * DOS compilers provide far-pointer versions of memcpy() and memset() even 363 * in the small-model libraries. These will be used if USE_FMEM is defined. 364 * Otherwise, the routines in jutils.c do it the hard way. 365 */ 366 367 #ifndef NEED_FAR_POINTERS /* normal case, same as regular macro */ 368 #define FMEMZERO(target,size) MEMZERO(target,size) 369 #else /* 80x86 case */ 370 #ifdef USE_FMEM 371 #define FMEMZERO(target,size) _fmemset((void FAR *)(target), 0, (size_t)(size)) 372 #else 373 EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero)); 374 #define FMEMZERO(target,size) jzero_far(target, size) 375 #endif 376 #endif 377 378 379 /* Compression module initialization routines */ 380 EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo)); 381 EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo, 382 boolean transcode_only)); 383 EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo, 384 boolean need_full_buffer)); 385 EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo, 386 boolean need_full_buffer)); 387 EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo, 388 boolean need_full_buffer)); 389 EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo)); 390 EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo)); 391 EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo)); 392 EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo)); 393 EXTERN(void) jinit_arith_encoder JPP((j_compress_ptr cinfo)); 394 EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo)); 395 /* Decompression module initialization routines */ 396 EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo)); 397 EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo, 398 boolean need_full_buffer)); 399 EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo, 400 boolean need_full_buffer)); 401 EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo, 402 boolean need_full_buffer)); 403 EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo)); 404 EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo)); 405 EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo)); 406 EXTERN(void) jinit_arith_decoder JPP((j_decompress_ptr cinfo)); 407 EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo)); 408 EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo)); 409 EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo)); 410 EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo)); 411 EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo)); 412 EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo)); 413 /* Memory manager initialization */ 414 EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo)); 415 416 /* Utility routines in jutils.c */ 417 EXTERN(long) jdiv_round_up JPP((long a, long b)); 418 EXTERN(long) jround_up JPP((long a, long b)); 419 EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row, 420 JSAMPARRAY output_array, int dest_row, 421 int num_rows, JDIMENSION num_cols)); 422 EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row, 423 JDIMENSION num_blocks)); 424 /* Constant tables in jutils.c */ 425 #if 0 /* This table is not actually needed in v6a */ 426 extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */ 427 #endif 428 extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */ 429 extern const int jpeg_natural_order7[]; /* zz to natural order for 7x7 block */ 430 extern const int jpeg_natural_order6[]; /* zz to natural order for 6x6 block */ 431 extern const int jpeg_natural_order5[]; /* zz to natural order for 5x5 block */ 432 extern const int jpeg_natural_order4[]; /* zz to natural order for 4x4 block */ 433 extern const int jpeg_natural_order3[]; /* zz to natural order for 3x3 block */ 434 extern const int jpeg_natural_order2[]; /* zz to natural order for 2x2 block */ 435 436 /* Arithmetic coding probability estimation tables in jaricom.c */ 437 extern const INT32 jpeg_aritab[]; 438 439 /* Suppress undefined-structure complaints if necessary. */ 440 441 #ifdef INCOMPLETE_TYPES_BROKEN 442 #ifndef AM_MEMORY_MANAGER /* only jmemmgr.c defines these */ 443 struct jvirt_sarray_control { long dummy; }; 444 struct jvirt_barray_control { long dummy; }; 445 #endif 446 #endif /* INCOMPLETE_TYPES_BROKEN */ 447