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, D. R. Commander. 9 * Copyright (C) 2015, Google, Inc. 10 * For conditions of distribution and use, see the accompanying README.ijg 11 * file. 12 * 13 * This file provides common declarations for the various JPEG modules. 14 * These declarations are considered internal to the JPEG library; most 15 * applications using the library shouldn't need to include this file. 16 */ 17 18 19 /* Declarations for both compression & decompression */ 20 21 typedef enum { /* Operating modes for buffer controllers */ 22 JBUF_PASS_THRU, /* Plain stripwise operation */ 23 /* Remaining modes require a full-image buffer to have been created */ 24 JBUF_SAVE_SOURCE, /* Run source subobject only, save output */ 25 JBUF_CRANK_DEST, /* Run dest subobject only, using saved data */ 26 JBUF_SAVE_AND_PASS /* Run both subobjects, save output */ 27 } J_BUF_MODE; 28 29 /* Values of global_state field (jdapi.c has some dependencies on ordering!) */ 30 #define CSTATE_START 100 /* after create_compress */ 31 #define CSTATE_SCANNING 101 /* start_compress done, write_scanlines OK */ 32 #define CSTATE_RAW_OK 102 /* start_compress done, write_raw_data OK */ 33 #define CSTATE_WRCOEFS 103 /* jpeg_write_coefficients done */ 34 #define DSTATE_START 200 /* after create_decompress */ 35 #define DSTATE_INHEADER 201 /* reading header markers, no SOS yet */ 36 #define DSTATE_READY 202 /* found SOS, ready for start_decompress */ 37 #define DSTATE_PRELOAD 203 /* reading multiscan file in start_decompress*/ 38 #define DSTATE_PRESCAN 204 /* performing dummy pass for 2-pass quant */ 39 #define DSTATE_SCANNING 205 /* start_decompress done, read_scanlines OK */ 40 #define DSTATE_RAW_OK 206 /* start_decompress done, read_raw_data OK */ 41 #define DSTATE_BUFIMAGE 207 /* expecting jpeg_start_output */ 42 #define DSTATE_BUFPOST 208 /* looking for SOS/EOI in jpeg_finish_output */ 43 #define DSTATE_RDCOEFS 209 /* reading file in jpeg_read_coefficients */ 44 #define DSTATE_STOPPING 210 /* looking for EOI in jpeg_finish_decompress */ 45 46 47 /* JLONG must hold at least signed 32-bit values. */ 48 typedef long JLONG; 49 50 51 /* 52 * Left shift macro that handles a negative operand without causing any 53 * sanitizer warnings 54 */ 55 56 #define LEFT_SHIFT(a, b) ((JLONG)((unsigned long)(a) << (b))) 57 58 59 /* Declarations for compression modules */ 60 61 /* Master control module */ 62 struct jpeg_comp_master { 63 void (*prepare_for_pass) (j_compress_ptr cinfo); 64 void (*pass_startup) (j_compress_ptr cinfo); 65 void (*finish_pass) (j_compress_ptr cinfo); 66 67 /* State variables made visible to other modules */ 68 boolean call_pass_startup; /* True if pass_startup must be called */ 69 boolean is_last_pass; /* True during last pass */ 70 }; 71 72 /* Main buffer control (downsampled-data buffer) */ 73 struct jpeg_c_main_controller { 74 void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode); 75 void (*process_data) (j_compress_ptr cinfo, JSAMPARRAY input_buf, 76 JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail); 77 }; 78 79 /* Compression preprocessing (downsampling input buffer control) */ 80 struct jpeg_c_prep_controller { 81 void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode); 82 void (*pre_process_data) (j_compress_ptr cinfo, JSAMPARRAY input_buf, 83 JDIMENSION *in_row_ctr, JDIMENSION in_rows_avail, 84 JSAMPIMAGE output_buf, 85 JDIMENSION *out_row_group_ctr, 86 JDIMENSION out_row_groups_avail); 87 }; 88 89 /* Coefficient buffer control */ 90 struct jpeg_c_coef_controller { 91 void (*start_pass) (j_compress_ptr cinfo, J_BUF_MODE pass_mode); 92 boolean (*compress_data) (j_compress_ptr cinfo, JSAMPIMAGE input_buf); 93 }; 94 95 /* Colorspace conversion */ 96 struct jpeg_color_converter { 97 void (*start_pass) (j_compress_ptr cinfo); 98 void (*color_convert) (j_compress_ptr cinfo, JSAMPARRAY input_buf, 99 JSAMPIMAGE output_buf, JDIMENSION output_row, 100 int num_rows); 101 }; 102 103 /* Downsampling */ 104 struct jpeg_downsampler { 105 void (*start_pass) (j_compress_ptr cinfo); 106 void (*downsample) (j_compress_ptr cinfo, JSAMPIMAGE input_buf, 107 JDIMENSION in_row_index, JSAMPIMAGE output_buf, 108 JDIMENSION out_row_group_index); 109 110 boolean need_context_rows; /* TRUE if need rows above & below */ 111 }; 112 113 /* Forward DCT (also controls coefficient quantization) */ 114 struct jpeg_forward_dct { 115 void (*start_pass) (j_compress_ptr cinfo); 116 /* perhaps this should be an array??? */ 117 void (*forward_DCT) (j_compress_ptr cinfo, jpeg_component_info *compptr, 118 JSAMPARRAY sample_data, JBLOCKROW coef_blocks, 119 JDIMENSION start_row, JDIMENSION start_col, 120 JDIMENSION num_blocks); 121 }; 122 123 /* Entropy encoding */ 124 struct jpeg_entropy_encoder { 125 void (*start_pass) (j_compress_ptr cinfo, boolean gather_statistics); 126 boolean (*encode_mcu) (j_compress_ptr cinfo, JBLOCKROW *MCU_data); 127 void (*finish_pass) (j_compress_ptr cinfo); 128 }; 129 130 /* Marker writing */ 131 struct jpeg_marker_writer { 132 void (*write_file_header) (j_compress_ptr cinfo); 133 void (*write_frame_header) (j_compress_ptr cinfo); 134 void (*write_scan_header) (j_compress_ptr cinfo); 135 void (*write_file_trailer) (j_compress_ptr cinfo); 136 void (*write_tables_only) (j_compress_ptr cinfo); 137 /* These routines are exported to allow insertion of extra markers */ 138 /* Probably only COM and APPn markers should be written this way */ 139 void (*write_marker_header) (j_compress_ptr cinfo, int marker, 140 unsigned int datalen); 141 void (*write_marker_byte) (j_compress_ptr cinfo, int val); 142 }; 143 144 145 /* Declarations for decompression modules */ 146 147 /* Master control module */ 148 struct jpeg_decomp_master { 149 void (*prepare_for_output_pass) (j_decompress_ptr cinfo); 150 void (*finish_output_pass) (j_decompress_ptr cinfo); 151 152 /* State variables made visible to other modules */ 153 boolean is_dummy_pass; /* True during 1st pass for 2-pass quant */ 154 155 /* Partial decompression variables */ 156 JDIMENSION first_iMCU_col; 157 JDIMENSION last_iMCU_col; 158 JDIMENSION first_MCU_col[MAX_COMPONENTS]; 159 JDIMENSION last_MCU_col[MAX_COMPONENTS]; 160 boolean jinit_upsampler_no_alloc; 161 }; 162 163 /* Input control module */ 164 struct jpeg_input_controller { 165 int (*consume_input) (j_decompress_ptr cinfo); 166 void (*reset_input_controller) (j_decompress_ptr cinfo); 167 void (*start_input_pass) (j_decompress_ptr cinfo); 168 void (*finish_input_pass) (j_decompress_ptr cinfo); 169 170 /* State variables made visible to other modules */ 171 boolean has_multiple_scans; /* True if file has multiple scans */ 172 boolean eoi_reached; /* True when EOI has been consumed */ 173 }; 174 175 /* Main buffer control (downsampled-data buffer) */ 176 struct jpeg_d_main_controller { 177 void (*start_pass) (j_decompress_ptr cinfo, J_BUF_MODE pass_mode); 178 void (*process_data) (j_decompress_ptr cinfo, JSAMPARRAY output_buf, 179 JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail); 180 }; 181 182 /* Coefficient buffer control */ 183 struct jpeg_d_coef_controller { 184 void (*start_input_pass) (j_decompress_ptr cinfo); 185 int (*consume_data) (j_decompress_ptr cinfo); 186 void (*start_output_pass) (j_decompress_ptr cinfo); 187 int (*decompress_data) (j_decompress_ptr cinfo, JSAMPIMAGE output_buf); 188 /* Pointer to array of coefficient virtual arrays, or NULL if none */ 189 jvirt_barray_ptr *coef_arrays; 190 }; 191 192 /* Decompression postprocessing (color quantization buffer control) */ 193 struct jpeg_d_post_controller { 194 void (*start_pass) (j_decompress_ptr cinfo, J_BUF_MODE pass_mode); 195 void (*post_process_data) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, 196 JDIMENSION *in_row_group_ctr, 197 JDIMENSION in_row_groups_avail, 198 JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, 199 JDIMENSION out_rows_avail); 200 }; 201 202 /* Marker reading & parsing */ 203 struct jpeg_marker_reader { 204 void (*reset_marker_reader) (j_decompress_ptr cinfo); 205 /* Read markers until SOS or EOI. 206 * Returns same codes as are defined for jpeg_consume_input: 207 * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. 208 */ 209 int (*read_markers) (j_decompress_ptr cinfo); 210 /* Read a restart marker --- exported for use by entropy decoder only */ 211 jpeg_marker_parser_method read_restart_marker; 212 213 /* State of marker reader --- nominally internal, but applications 214 * supplying COM or APPn handlers might like to know the state. 215 */ 216 boolean saw_SOI; /* found SOI? */ 217 boolean saw_SOF; /* found SOF? */ 218 int next_restart_num; /* next restart number expected (0-7) */ 219 unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */ 220 }; 221 222 /* Entropy decoding */ 223 struct jpeg_entropy_decoder { 224 void (*start_pass) (j_decompress_ptr cinfo); 225 boolean (*decode_mcu) (j_decompress_ptr cinfo, JBLOCKROW *MCU_data); 226 227 /* This is here to share code between baseline and progressive decoders; */ 228 /* other modules probably should not use it */ 229 boolean insufficient_data; /* set TRUE after emitting warning */ 230 }; 231 232 /* Inverse DCT (also performs dequantization) */ 233 typedef void (*inverse_DCT_method_ptr) (j_decompress_ptr cinfo, 234 jpeg_component_info *compptr, 235 JCOEFPTR coef_block, 236 JSAMPARRAY output_buf, 237 JDIMENSION output_col); 238 239 struct jpeg_inverse_dct { 240 void (*start_pass) (j_decompress_ptr cinfo); 241 /* It is useful to allow each component to have a separate IDCT method. */ 242 inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS]; 243 }; 244 245 /* Upsampling (note that upsampler must also call color converter) */ 246 struct jpeg_upsampler { 247 void (*start_pass) (j_decompress_ptr cinfo); 248 void (*upsample) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, 249 JDIMENSION *in_row_group_ctr, 250 JDIMENSION in_row_groups_avail, JSAMPARRAY output_buf, 251 JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail); 252 253 boolean need_context_rows; /* TRUE if need rows above & below */ 254 }; 255 256 /* Colorspace conversion */ 257 struct jpeg_color_deconverter { 258 void (*start_pass) (j_decompress_ptr cinfo); 259 void (*color_convert) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf, 260 JDIMENSION input_row, JSAMPARRAY output_buf, 261 int num_rows); 262 }; 263 264 /* Color quantization or color precision reduction */ 265 struct jpeg_color_quantizer { 266 void (*start_pass) (j_decompress_ptr cinfo, boolean is_pre_scan); 267 void (*color_quantize) (j_decompress_ptr cinfo, JSAMPARRAY input_buf, 268 JSAMPARRAY output_buf, int num_rows); 269 void (*finish_pass) (j_decompress_ptr cinfo); 270 void (*new_color_map) (j_decompress_ptr cinfo); 271 }; 272 273 274 /* Miscellaneous useful macros */ 275 276 #undef MAX 277 #define MAX(a,b) ((a) > (b) ? (a) : (b)) 278 #undef MIN 279 #define MIN(a,b) ((a) < (b) ? (a) : (b)) 280 281 282 /* We assume that right shift corresponds to signed division by 2 with 283 * rounding towards minus infinity. This is correct for typical "arithmetic 284 * shift" instructions that shift in copies of the sign bit. But some 285 * C compilers implement >> with an unsigned shift. For these machines you 286 * must define RIGHT_SHIFT_IS_UNSIGNED. 287 * RIGHT_SHIFT provides a proper signed right shift of a JLONG quantity. 288 * It is only applied with constant shift counts. SHIFT_TEMPS must be 289 * included in the variables of any routine using RIGHT_SHIFT. 290 */ 291 292 #ifdef RIGHT_SHIFT_IS_UNSIGNED 293 #define SHIFT_TEMPS JLONG shift_temp; 294 #define RIGHT_SHIFT(x,shft) \ 295 ((shift_temp = (x)) < 0 ? \ 296 (shift_temp >> (shft)) | ((~((JLONG) 0)) << (32-(shft))) : \ 297 (shift_temp >> (shft))) 298 #else 299 #define SHIFT_TEMPS 300 #define RIGHT_SHIFT(x,shft) ((x) >> (shft)) 301 #endif 302 303 304 /* Compression module initialization routines */ 305 EXTERN(void) jinit_compress_master (j_compress_ptr cinfo); 306 EXTERN(void) jinit_c_master_control (j_compress_ptr cinfo, 307 boolean transcode_only); 308 EXTERN(void) jinit_c_main_controller (j_compress_ptr cinfo, 309 boolean need_full_buffer); 310 EXTERN(void) jinit_c_prep_controller (j_compress_ptr cinfo, 311 boolean need_full_buffer); 312 EXTERN(void) jinit_c_coef_controller (j_compress_ptr cinfo, 313 boolean need_full_buffer); 314 EXTERN(void) jinit_color_converter (j_compress_ptr cinfo); 315 EXTERN(void) jinit_downsampler (j_compress_ptr cinfo); 316 EXTERN(void) jinit_forward_dct (j_compress_ptr cinfo); 317 EXTERN(void) jinit_huff_encoder (j_compress_ptr cinfo); 318 EXTERN(void) jinit_phuff_encoder (j_compress_ptr cinfo); 319 EXTERN(void) jinit_arith_encoder (j_compress_ptr cinfo); 320 EXTERN(void) jinit_marker_writer (j_compress_ptr cinfo); 321 /* Decompression module initialization routines */ 322 EXTERN(void) jinit_master_decompress (j_decompress_ptr cinfo); 323 EXTERN(void) jinit_d_main_controller (j_decompress_ptr cinfo, 324 boolean need_full_buffer); 325 EXTERN(void) jinit_d_coef_controller (j_decompress_ptr cinfo, 326 boolean need_full_buffer); 327 EXTERN(void) jinit_d_post_controller (j_decompress_ptr cinfo, 328 boolean need_full_buffer); 329 EXTERN(void) jinit_input_controller (j_decompress_ptr cinfo); 330 EXTERN(void) jinit_marker_reader (j_decompress_ptr cinfo); 331 EXTERN(void) jinit_huff_decoder (j_decompress_ptr cinfo); 332 EXTERN(void) jinit_phuff_decoder (j_decompress_ptr cinfo); 333 EXTERN(void) jinit_arith_decoder (j_decompress_ptr cinfo); 334 EXTERN(void) jinit_inverse_dct (j_decompress_ptr cinfo); 335 EXTERN(void) jinit_upsampler (j_decompress_ptr cinfo); 336 EXTERN(void) jinit_color_deconverter (j_decompress_ptr cinfo); 337 EXTERN(void) jinit_1pass_quantizer (j_decompress_ptr cinfo); 338 EXTERN(void) jinit_2pass_quantizer (j_decompress_ptr cinfo); 339 EXTERN(void) jinit_merged_upsampler (j_decompress_ptr cinfo); 340 /* Memory manager initialization */ 341 EXTERN(void) jinit_memory_mgr (j_common_ptr cinfo); 342 343 /* Utility routines in jutils.c */ 344 EXTERN(long) jdiv_round_up (long a, long b); 345 EXTERN(long) jround_up (long a, long b); 346 EXTERN(void) jcopy_sample_rows (JSAMPARRAY input_array, int source_row, 347 JSAMPARRAY output_array, int dest_row, 348 int num_rows, JDIMENSION num_cols); 349 EXTERN(void) jcopy_block_row (JBLOCKROW input_row, JBLOCKROW output_row, 350 JDIMENSION num_blocks); 351 EXTERN(void) jzero_far (void *target, size_t bytestozero); 352 /* Constant tables in jutils.c */ 353 #if 0 /* This table is not actually needed in v6a */ 354 extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */ 355 #endif 356 extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */ 357 358 /* Arithmetic coding probability estimation tables in jaricom.c */ 359 extern const JLONG jpeg_aritab[]; 360 361 /* Suppress undefined-structure complaints if necessary. */ 362 363 #ifdef INCOMPLETE_TYPES_BROKEN 364 #ifndef AM_MEMORY_MANAGER /* only jmemmgr.c defines these */ 365 struct jvirt_sarray_control { long dummy; }; 366 struct jvirt_barray_control { long dummy; }; 367 #endif 368 #endif /* INCOMPLETE_TYPES_BROKEN */ 369