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