1 /* 2 * jpegint.h 3 * 4 * This file was part of the Independent JPEG Group's software: 5 * Copyright (C) 1991-1997, Thomas G. Lane. 6 * Modified 1997-2009 by Guido Vollbeding. 7 * libjpeg-turbo Modifications: 8 * Copyright (C) 2015-2016, 2019, 2021, D. R. Commander. 9 * Copyright (C) 2015, Google, Inc. 10 * Copyright (C) 2021, Alex Richardson. 11 * For conditions of distribution and use, see the accompanying README.ijg 12 * file. 13 * 14 * This file provides common declarations for the various JPEG modules. 15 * These declarations are considered internal to the JPEG library; most 16 * applications using the library shouldn't need to include this file. 17 */ 18 19 20 /* Declarations for both compression & decompression */ 21 22 typedef enum { /* Operating modes for buffer controllers */ 23 JBUF_PASS_THRU, /* Plain stripwise operation */ 24 /* Remaining modes require a full-image buffer to have been created */ 25 JBUF_SAVE_SOURCE, /* Run source subobject only, save output */ 26 JBUF_CRANK_DEST, /* Run dest subobject only, using saved data */ 27 JBUF_SAVE_AND_PASS /* Run both subobjects, save output */ 28 } J_BUF_MODE; 29 30 /* Values of global_state field (jdapi.c has some dependencies on ordering!) */ 31 #define CSTATE_START 100 /* after create_compress */ 32 #define CSTATE_SCANNING 101 /* start_compress done, write_scanlines OK */ 33 #define CSTATE_RAW_OK 102 /* start_compress done, write_raw_data OK */ 34 #define CSTATE_WRCOEFS 103 /* jpeg_write_coefficients done */ 35 #define DSTATE_START 200 /* after create_decompress */ 36 #define DSTATE_INHEADER 201 /* reading header markers, no SOS yet */ 37 #define DSTATE_READY 202 /* found SOS, ready for start_decompress */ 38 #define DSTATE_PRELOAD 203 /* reading multiscan file in start_decompress*/ 39 #define DSTATE_PRESCAN 204 /* performing dummy pass for 2-pass quant */ 40 #define DSTATE_SCANNING 205 /* start_decompress done, read_scanlines OK */ 41 #define DSTATE_RAW_OK 206 /* start_decompress done, read_raw_data OK */ 42 #define DSTATE_BUFIMAGE 207 /* expecting jpeg_start_output */ 43 #define DSTATE_BUFPOST 208 /* looking for SOS/EOI in jpeg_finish_output */ 44 #define DSTATE_RDCOEFS 209 /* reading file in jpeg_read_coefficients */ 45 #define DSTATE_STOPPING 210 /* looking for EOI in jpeg_finish_decompress */ 46 47 48 /* JLONG must hold at least signed 32-bit values. */ 49 typedef long JLONG; 50 51 /* JUINTPTR must hold pointer values. */ 52 #ifdef __UINTPTR_TYPE__ 53 /* 54 * __UINTPTR_TYPE__ is GNU-specific and available in GCC 4.6+ and Clang 3.0+. 55 * Fortunately, that is sufficient to support the few architectures for which 56 * sizeof(void *) != sizeof(size_t). The only other options would require C99 57 * or Clang-specific builtins. 58 */ 59 typedef __UINTPTR_TYPE__ JUINTPTR; 60 #else 61 typedef size_t JUINTPTR; 62 #endif 63 64 /* 65 * Left shift macro that handles a negative operand without causing any 66 * sanitizer warnings 67 */ 68 69 #define LEFT_SHIFT(a, b) ((JLONG)((unsigned long)(a) << (b))) 70 71 72 /* Declarations for compression modules */ 73 74 /* Master control module */ 75 struct jpeg_comp_master { 76 void (*prepare_for_pass) (j_compress_ptr cinfo); 77 void (*pass_startup) (j_compress_ptr cinfo); 78 void (*finish_pass) (j_compress_ptr cinfo); 79 80 /* State variables made visible to other modules */ 81 boolean call_pass_startup; /* True if pass_startup must be called */ 82 boolean is_last_pass; /* True during last pass */ 83 }; 84 85 /* Main buffer control (downsampled-data buffer) */ 86 struct jpeg_c_main_controller { 87 void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode); 88 void (*process_data) (j_compress_ptr cinfo, JSAMPARRAY input_buf, 89 JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail); 90 }; 91 92 /* Compression preprocessing (downsampling input buffer control) */ 93 struct jpeg_c_prep_controller { 94 void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode); 95 void (*pre_process_data) (j_compress_ptr cinfo, JSAMPARRAY input_buf, 96 JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail, 97 JSAMPIMAGE output_buf, 98 JDIMENSION *out_row_group_ctr, 99 JDIMENSION out_row_groups_avail); 100 }; 101 102 /* Coefficient buffer control */ 103 struct jpeg_c_coef_controller { 104 void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode); 105 boolean (*compress_data) (j_compress_ptr cinfo, JSAMPIMAGE input_buf); 106 }; 107 108 /* Colorspace conversion */ 109 struct jpeg_color_converter { 110 void (*start_pass) (j_compress_ptr cinfo); 111 void (*color_convert) (j_compress_ptr cinfo, JSAMPARRAY input_buf, 112 JSAMPIMAGE output_buf, JDIMENSION output_row, 113 int num_rows); 114 }; 115 116 /* Downsampling */ 117 struct jpeg_downsampler { 118 void (*start_pass) (j_compress_ptr cinfo); 119 void (*downsample) (j_compress_ptr cinfo, JSAMPIMAGE input_buf, 120 JDIMENSION in_row_index, JSAMPIMAGE output_buf, 121 JDIMENSION out_row_group_index); 122 123 boolean need_context_rows; /* TRUE if need rows above & below */ 124 }; 125 126 /* Forward DCT (also controls coefficient quantization) */ 127 struct jpeg_forward_dct { 128 void (*start_pass) (j_compress_ptr cinfo); 129 /* perhaps this should be an array??? */ 130 void (*forward_DCT) (j_compress_ptr cinfo, jpeg_component_info *compptr, 131 JSAMPARRAY sample_data, JBLOCKROW coef_blocks, 132 JDIMENSION start_row, JDIMENSION start_col, 133 JDIMENSION num_blocks); 134 }; 135 136 /* Entropy encoding */ 137 struct jpeg_entropy_encoder { 138 void (*start_pass) (j_compress_ptr cinfo, boolean gather_statistics); 139 boolean (*encode_mcu) (j_compress_ptr cinfo, JBLOCKROW *MCU_data); 140 void (*finish_pass) (j_compress_ptr cinfo); 141 }; 142 143 /* Marker writing */ 144 struct jpeg_marker_writer { 145 void (*write_file_header) (j_compress_ptr cinfo); 146 void (*write_frame_header) (j_compress_ptr cinfo); 147 void (*write_scan_header) (j_compress_ptr cinfo); 148 void (*write_file_trailer) (j_compress_ptr cinfo); 149 void (*write_tables_only) (j_compress_ptr cinfo); 150 /* These routines are exported to allow insertion of extra markers */ 151 /* Probably only COM and APPn markers should be written this way */ 152 void (*write_marker_header) (j_compress_ptr cinfo, int marker, 153 unsigned int datalen); 154 void (*write_marker_byte) (j_compress_ptr cinfo, int val); 155 }; 156 157 158 /* Declarations for decompression modules */ 159 160 /* Master control module */ 161 struct jpeg_decomp_master { 162 void (*prepare_for_output_pass) (j_decompress_ptr cinfo); 163 void (*finish_output_pass) (j_decompress_ptr cinfo); 164 165 /* State variables made visible to other modules */ 166 boolean is_dummy_pass; /* True during 1st pass for 2-pass quant */ 167 168 /* Partial decompression variables */ 169 JDIMENSION first_iMCU_col; 170 JDIMENSION last_iMCU_col; 171 JDIMENSION first_MCU_col[MAX_COMPONENTS]; 172 JDIMENSION last_MCU_col[MAX_COMPONENTS]; 173 boolean jinit_upsampler_no_alloc; 174 175 /* Last iMCU row that was successfully decoded */ 176 JDIMENSION last_good_iMCU_row; 177 }; 178 179 /* Input control module */ 180 struct jpeg_input_controller { 181 int (*consume_input) (j_decompress_ptr cinfo); 182 void (*reset_input_controller) (j_decompress_ptr cinfo); 183 void (*start_input_pass) (j_decompress_ptr cinfo); 184 void (*finish_input_pass) (j_decompress_ptr cinfo); 185 186 /* State variables made visible to other modules */ 187 boolean has_multiple_scans; /* True if file has multiple scans */ 188 boolean eoi_reached; /* True when EOI has been consumed */ 189 }; 190 191 /* Main buffer control (downsampled-data buffer) */ 192 struct jpeg_d_main_controller { 193 void (*start_pass) (j_decompress_ptr cinfo, J_BUF_MODE pass_mode); 194 void (*process_data) (j_decompress_ptr cinfo, JSAMPARRAY output_buf, 195 JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail); 196 }; 197 198 /* Coefficient buffer control */ 199 struct jpeg_d_coef_controller { 200 void (*start_input_pass) (j_decompress_ptr cinfo); 201 int (*consume_data) (j_decompress_ptr cinfo); 202 void (*start_output_pass) (j_decompress_ptr cinfo); 203 int (*decompress_data) (j_decompress_ptr cinfo, JSAMPIMAGE output_buf); 204 /* Pointer to array of coefficient virtual arrays, or NULL if none */ 205 jvirt_barray_ptr *coef_arrays; 206 }; 207 208 /* Decompression postprocessing (color quantization buffer control) */ 209 struct jpeg_d_post_controller { 210 void (*start_pass) (j_decompress_ptr cinfo, J_BUF_MODE pass_mode); 211 void (*post_process_data) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, 212 JDIMENSION *in_row_group_ctr, 213 JDIMENSION in_row_groups_avail, 214 JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, 215 JDIMENSION out_rows_avail); 216 }; 217 218 /* Marker reading & parsing */ 219 struct jpeg_marker_reader { 220 void (*reset_marker_reader) (j_decompress_ptr cinfo); 221 /* Read markers until SOS or EOI. 222 * Returns same codes as are defined for jpeg_consume_input: 223 * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. 224 */ 225 int (*read_markers) (j_decompress_ptr cinfo); 226 /* Read a restart marker --- exported for use by entropy decoder only */ 227 jpeg_marker_parser_method read_restart_marker; 228 229 /* State of marker reader --- nominally internal, but applications 230 * supplying COM or APPn handlers might like to know the state. 231 */ 232 boolean saw_SOI; /* found SOI? */ 233 boolean saw_SOF; /* found SOF? */ 234 int next_restart_num; /* next restart number expected (0-7) */ 235 unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */ 236 }; 237 238 /* Entropy decoding */ 239 struct jpeg_entropy_decoder { 240 void (*start_pass) (j_decompress_ptr cinfo); 241 boolean (*decode_mcu) (j_decompress_ptr cinfo, JBLOCKROW *MCU_data); 242 243 /* This is here to share code between baseline and progressive decoders; */ 244 /* other modules probably should not use it */ 245 boolean insufficient_data; /* set TRUE after emitting warning */ 246 }; 247 248 /* Inverse DCT (also performs dequantization) */ 249 typedef void (*inverse_DCT_method_ptr) (j_decompress_ptr cinfo, 250 jpeg_component_info *compptr, 251 JCOEFPTR coef_block, 252 JSAMPARRAY output_buf, 253 JDIMENSION output_col); 254 255 struct jpeg_inverse_dct { 256 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 void (*start_pass) (j_decompress_ptr cinfo); 264 void (*upsample) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, 265 JDIMENSION *in_row_group_ctr, 266 JDIMENSION in_row_groups_avail, JSAMPARRAY output_buf, 267 JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail); 268 269 boolean need_context_rows; /* TRUE if need rows above & below */ 270 }; 271 272 /* Colorspace conversion */ 273 struct jpeg_color_deconverter { 274 void (*start_pass) (j_decompress_ptr cinfo); 275 void (*color_convert) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, 276 JDIMENSION input_row, JSAMPARRAY output_buf, 277 int num_rows); 278 }; 279 280 /* Color quantization or color precision reduction */ 281 struct jpeg_color_quantizer { 282 void (*start_pass) (j_decompress_ptr cinfo, boolean is_pre_scan); 283 void (*color_quantize) (j_decompress_ptr cinfo, JSAMPARRAY input_buf, 284 JSAMPARRAY output_buf, int num_rows); 285 void (*finish_pass) (j_decompress_ptr cinfo); 286 void (*new_color_map) (j_decompress_ptr cinfo); 287 }; 288 289 290 /* Miscellaneous useful macros */ 291 292 #undef MAX 293 #define MAX(a, b) ((a) > (b) ? (a) : (b)) 294 #undef MIN 295 #define MIN(a, b) ((a) < (b) ? (a) : (b)) 296 297 298 /* We assume that right shift corresponds to signed division by 2 with 299 * rounding towards minus infinity. This is correct for typical "arithmetic 300 * shift" instructions that shift in copies of the sign bit. But some 301 * C compilers implement >> with an unsigned shift. For these machines you 302 * must define RIGHT_SHIFT_IS_UNSIGNED. 303 * RIGHT_SHIFT provides a proper signed right shift of a JLONG quantity. 304 * It is only applied with constant shift counts. SHIFT_TEMPS must be 305 * included in the variables of any routine using RIGHT_SHIFT. 306 */ 307 308 #ifdef RIGHT_SHIFT_IS_UNSIGNED 309 #define SHIFT_TEMPS JLONG shift_temp; 310 #define RIGHT_SHIFT(x, shft) \ 311 ((shift_temp = (x)) < 0 ? \ 312 (shift_temp >> (shft)) | ((~((JLONG)0)) << (32 - (shft))) : \ 313 (shift_temp >> (shft))) 314 #else 315 #define SHIFT_TEMPS 316 #define RIGHT_SHIFT(x, shft) ((x) >> (shft)) 317 #endif 318 319 320 /* Compression module initialization routines */ 321 EXTERN(void) jinit_compress_master(j_compress_ptr cinfo); 322 EXTERN(void) jinit_c_master_control(j_compress_ptr cinfo, 323 boolean transcode_only); 324 EXTERN(void) jinit_c_main_controller(j_compress_ptr cinfo, 325 boolean need_full_buffer); 326 EXTERN(void) jinit_c_prep_controller(j_compress_ptr cinfo, 327 boolean need_full_buffer); 328 EXTERN(void) jinit_c_coef_controller(j_compress_ptr cinfo, 329 boolean need_full_buffer); 330 EXTERN(void) jinit_color_converter(j_compress_ptr cinfo); 331 EXTERN(void) jinit_downsampler(j_compress_ptr cinfo); 332 EXTERN(void) jinit_forward_dct(j_compress_ptr cinfo); 333 EXTERN(void) jinit_huff_encoder(j_compress_ptr cinfo); 334 EXTERN(void) jinit_phuff_encoder(j_compress_ptr cinfo); 335 EXTERN(void) jinit_arith_encoder(j_compress_ptr cinfo); 336 EXTERN(void) jinit_marker_writer(j_compress_ptr cinfo); 337 /* Decompression module initialization routines */ 338 EXTERN(void) jinit_master_decompress(j_decompress_ptr cinfo); 339 EXTERN(void) jinit_d_main_controller(j_decompress_ptr cinfo, 340 boolean need_full_buffer); 341 EXTERN(void) jinit_d_coef_controller(j_decompress_ptr cinfo, 342 boolean need_full_buffer); 343 EXTERN(void) jinit_d_post_controller(j_decompress_ptr cinfo, 344 boolean need_full_buffer); 345 EXTERN(void) jinit_input_controller(j_decompress_ptr cinfo); 346 EXTERN(void) jinit_marker_reader(j_decompress_ptr cinfo); 347 EXTERN(void) jinit_huff_decoder(j_decompress_ptr cinfo); 348 EXTERN(void) jinit_phuff_decoder(j_decompress_ptr cinfo); 349 EXTERN(void) jinit_arith_decoder(j_decompress_ptr cinfo); 350 EXTERN(void) jinit_inverse_dct(j_decompress_ptr cinfo); 351 EXTERN(void) jinit_upsampler(j_decompress_ptr cinfo); 352 EXTERN(void) jinit_color_deconverter(j_decompress_ptr cinfo); 353 EXTERN(void) jinit_1pass_quantizer(j_decompress_ptr cinfo); 354 EXTERN(void) jinit_2pass_quantizer(j_decompress_ptr cinfo); 355 EXTERN(void) jinit_merged_upsampler(j_decompress_ptr cinfo); 356 /* Memory manager initialization */ 357 EXTERN(void) jinit_memory_mgr(j_common_ptr cinfo); 358 359 /* Utility routines in jutils.c */ 360 EXTERN(long) jdiv_round_up(long a, long b); 361 EXTERN(long) jround_up(long a, long b); 362 EXTERN(void) jcopy_sample_rows(JSAMPARRAY input_array, int source_row, 363 JSAMPARRAY output_array, int dest_row, 364 int num_rows, JDIMENSION num_cols); 365 EXTERN(void) jcopy_block_row(JBLOCKROW input_row, JBLOCKROW output_row, 366 JDIMENSION num_blocks); 367 EXTERN(void) jzero_far(void *target, size_t bytestozero); 368 /* Constant tables in jutils.c */ 369 #if 0 /* This table is not actually needed in v6a */ 370 extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */ 371 #endif 372 extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */ 373 374 /* Arithmetic coding probability estimation tables in jaricom.c */ 375 extern const JLONG jpeg_aritab[]; 376