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 16typedef 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 */ 45struct 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) */ 56struct 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) */ 64struct 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 */ 76struct 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 */ 83struct 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 */ 91struct 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) */ 102struct 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 */ 113struct 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 */ 120struct 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 */ 137struct 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 */ 146struct jpeg_input_controller { 147 JMETHOD(int, consume_input, (j_decompress_ptr cinfo)); 148 JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo)); 149 JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo)); 150 JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo)); 151 152 /* State variables made visible to other modules */ 153 boolean has_multiple_scans; /* True if file has multiple scans */ 154 boolean eoi_reached; /* True when EOI has been consumed */ 155}; 156 157/* Main buffer control (downsampled-data buffer) */ 158struct jpeg_d_main_controller { 159 JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); 160 JMETHOD(void, process_data, (j_decompress_ptr cinfo, 161 JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, 162 JDIMENSION out_rows_avail)); 163}; 164 165/* Coefficient buffer control */ 166struct jpeg_d_coef_controller { 167 JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo)); 168 JMETHOD(int, consume_data, (j_decompress_ptr cinfo)); 169 JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo)); 170 JMETHOD(int, decompress_data, (j_decompress_ptr cinfo, 171 JSAMPIMAGE output_buf)); 172 /* Pointer to array of coefficient virtual arrays, or NULL if none */ 173 jvirt_barray_ptr *coef_arrays; 174}; 175 176/* Decompression postprocessing (color quantization buffer control) */ 177struct jpeg_d_post_controller { 178 JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)); 179 JMETHOD(void, post_process_data, (j_decompress_ptr cinfo, 180 JSAMPIMAGE input_buf, 181 JDIMENSION *in_row_group_ctr, 182 JDIMENSION in_row_groups_avail, 183 JSAMPARRAY output_buf, 184 JDIMENSION *out_row_ctr, 185 JDIMENSION out_rows_avail)); 186}; 187 188/* Marker reading & parsing */ 189struct jpeg_marker_reader { 190 JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo)); 191 /* Read markers until SOS or EOI. 192 * Returns same codes as are defined for jpeg_consume_input: 193 * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. 194 */ 195 JMETHOD(int, read_markers, (j_decompress_ptr cinfo)); 196 /* Read a restart marker --- exported for use by entropy decoder only */ 197 jpeg_marker_parser_method read_restart_marker; 198 199 /* State of marker reader --- nominally internal, but applications 200 * supplying COM or APPn handlers might like to know the state. 201 */ 202 boolean saw_SOI; /* found SOI? */ 203 boolean saw_SOF; /* found SOF? */ 204 int next_restart_num; /* next restart number expected (0-7) */ 205 unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */ 206}; 207 208/* Entropy decoding */ 209struct jpeg_entropy_decoder { 210 JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); 211 JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo, 212 JBLOCKROW *MCU_data)); 213 214 /* This is here to share code between baseline and progressive decoders; */ 215 /* other modules probably should not use it */ 216 boolean insufficient_data; /* set TRUE after emitting warning */ 217}; 218 219/* Inverse DCT (also performs dequantization) */ 220typedef JMETHOD(void, inverse_DCT_method_ptr, 221 (j_decompress_ptr cinfo, jpeg_component_info * compptr, 222 JCOEFPTR coef_block, 223 JSAMPARRAY output_buf, JDIMENSION output_col)); 224 225struct jpeg_inverse_dct { 226 JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); 227 /* It is useful to allow each component to have a separate IDCT method. */ 228 inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS]; 229}; 230 231/* Upsampling (note that upsampler must also call color converter) */ 232struct jpeg_upsampler { 233 JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); 234 JMETHOD(void, upsample, (j_decompress_ptr cinfo, 235 JSAMPIMAGE input_buf, 236 JDIMENSION *in_row_group_ctr, 237 JDIMENSION in_row_groups_avail, 238 JSAMPARRAY output_buf, 239 JDIMENSION *out_row_ctr, 240 JDIMENSION out_rows_avail)); 241 242 boolean need_context_rows; /* TRUE if need rows above & below */ 243}; 244 245/* Colorspace conversion */ 246struct jpeg_color_deconverter { 247 JMETHOD(void, start_pass, (j_decompress_ptr cinfo)); 248 JMETHOD(void, color_convert, (j_decompress_ptr cinfo, 249 JSAMPIMAGE input_buf, JDIMENSION input_row, 250 JSAMPARRAY output_buf, int num_rows)); 251}; 252 253/* Color quantization or color precision reduction */ 254struct jpeg_color_quantizer { 255 JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan)); 256 JMETHOD(void, color_quantize, (j_decompress_ptr cinfo, 257 JSAMPARRAY input_buf, JSAMPARRAY output_buf, 258 int num_rows)); 259 JMETHOD(void, finish_pass, (j_decompress_ptr cinfo)); 260 JMETHOD(void, new_color_map, (j_decompress_ptr cinfo)); 261}; 262 263 264/* Miscellaneous useful macros */ 265 266#undef MAX 267#define MAX(a,b) ((a) > (b) ? (a) : (b)) 268#undef MIN 269#define MIN(a,b) ((a) < (b) ? (a) : (b)) 270 271 272/* We assume that right shift corresponds to signed division by 2 with 273 * rounding towards minus infinity. This is correct for typical "arithmetic 274 * shift" instructions that shift in copies of the sign bit. But some 275 * C compilers implement >> with an unsigned shift. For these machines you 276 * must define RIGHT_SHIFT_IS_UNSIGNED. 277 * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity. 278 * It is only applied with constant shift counts. SHIFT_TEMPS must be 279 * included in the variables of any routine using RIGHT_SHIFT. 280 */ 281 282#ifdef RIGHT_SHIFT_IS_UNSIGNED 283#define SHIFT_TEMPS INT32 shift_temp; 284#define RIGHT_SHIFT(x,shft) \ 285 ((shift_temp = (x)) < 0 ? \ 286 (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \ 287 (shift_temp >> (shft))) 288#else 289#define SHIFT_TEMPS 290#define RIGHT_SHIFT(x,shft) ((x) >> (shft)) 291#endif 292 293 294/* Short forms of external names for systems with brain-damaged linkers. */ 295 296#ifdef NEED_SHORT_EXTERNAL_NAMES 297#define jinit_compress_master jICompress 298#define jinit_c_master_control jICMaster 299#define jinit_c_main_controller jICMainC 300#define jinit_c_prep_controller jICPrepC 301#define jinit_c_coef_controller jICCoefC 302#define jinit_color_converter jICColor 303#define jinit_downsampler jIDownsampler 304#define jinit_forward_dct jIFDCT 305#define jinit_huff_encoder jIHEncoder 306#define jinit_phuff_encoder jIPHEncoder 307#define jinit_marker_writer jIMWriter 308#define jinit_master_decompress jIDMaster 309#define jinit_d_main_controller jIDMainC 310#define jinit_d_coef_controller jIDCoefC 311#define jinit_d_post_controller jIDPostC 312#define jinit_input_controller jIInCtlr 313#define jinit_marker_reader jIMReader 314#define jinit_huff_decoder jIHDecoder 315#define jinit_phuff_decoder jIPHDecoder 316#define jinit_inverse_dct jIIDCT 317#define jinit_upsampler jIUpsampler 318#define jinit_color_deconverter jIDColor 319#define jinit_1pass_quantizer jI1Quant 320#define jinit_2pass_quantizer jI2Quant 321#define jinit_merged_upsampler jIMUpsampler 322#define jinit_memory_mgr jIMemMgr 323#define jdiv_round_up jDivRound 324#define jround_up jRound 325#define jcopy_sample_rows jCopySamples 326#define jcopy_block_row jCopyBlocks 327#define jzero_far jZeroFar 328#define jpeg_zigzag_order jZIGTable 329#define jpeg_natural_order jZAGTable 330#endif /* NEED_SHORT_EXTERNAL_NAMES */ 331 332 333/* Compression module initialization routines */ 334EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo)); 335EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo, 336 boolean transcode_only)); 337EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo, 338 boolean need_full_buffer)); 339EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo, 340 boolean need_full_buffer)); 341EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo, 342 boolean need_full_buffer)); 343EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo)); 344EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo)); 345EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo)); 346EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo)); 347EXTERN(void) jinit_phuff_encoder JPP((j_compress_ptr cinfo)); 348EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo)); 349/* Decompression module initialization routines */ 350EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo)); 351EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo, 352 boolean need_full_buffer)); 353EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo, 354 boolean need_full_buffer)); 355EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo, 356 boolean need_full_buffer)); 357EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo)); 358EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo)); 359EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo)); 360EXTERN(void) jinit_phuff_decoder JPP((j_decompress_ptr cinfo)); 361EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo)); 362EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo)); 363EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo)); 364EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo)); 365EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo)); 366EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo)); 367/* Memory manager initialization */ 368EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo)); 369 370/* Utility routines in jutils.c */ 371EXTERN(long) jdiv_round_up JPP((long a, long b)); 372EXTERN(long) jround_up JPP((long a, long b)); 373EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row, 374 JSAMPARRAY output_array, int dest_row, 375 int num_rows, JDIMENSION num_cols)); 376EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row, 377 JDIMENSION num_blocks)); 378EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero)); 379/* Constant tables in jutils.c */ 380#if 0 /* This table is not actually needed in v6a */ 381extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */ 382#endif 383extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */ 384 385/* Suppress undefined-structure complaints if necessary. */ 386 387#ifdef INCOMPLETE_TYPES_BROKEN 388#ifndef AM_MEMORY_MANAGER /* only jmemmgr.c defines these */ 389struct jvirt_sarray_control { long dummy; }; 390struct jvirt_barray_control { long dummy; }; 391#endif 392#endif /* INCOMPLETE_TYPES_BROKEN */ 393