media/libjpeg/jpegint.h

   1 /*
   2  * jpegint.h
   3  *
   4  * Copyright (C) 1991-1997, Thomas G. Lane.
   5  * Modified 1997-2009 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 struct jpeg_forward_dct {
 104   JMETHOD(void, start_pass, (j_compress_ptr cinfo));
 105   /* perhaps this should be an array??? */
 106   JMETHOD(void, forward_DCT, (j_compress_ptr cinfo,
 107                               jpeg_component_info * compptr,
 108                               JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
 109                               JDIMENSION start_row, JDIMENSION start_col,
 110                               JDIMENSION num_blocks));
 111 };
 112
 113 /* Entropy encoding */
 114 struct jpeg_entropy_encoder {
 115   JMETHOD(void, start_pass, (j_compress_ptr cinfo, boolean gather_statistics));
 116   JMETHOD(boolean, encode_mcu, (j_compress_ptr cinfo, JBLOCKROW *MCU_data));
 117   JMETHOD(void, finish_pass, (j_compress_ptr cinfo));
 118 };
 119
 120 /* Marker writing */
 121 struct jpeg_marker_writer {
 122   JMETHOD(void, write_file_header, (j_compress_ptr cinfo));
 123   JMETHOD(void, write_frame_header, (j_compress_ptr cinfo));
 124   JMETHOD(void, write_scan_header, (j_compress_ptr cinfo));
 125   JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo));
 126   JMETHOD(void, write_tables_only, (j_compress_ptr cinfo));
 127   /* These routines are exported to allow insertion of extra markers */
 128   /* Probably only COM and APPn markers should be written this way */
 129   JMETHOD(void, write_marker_header, (j_compress_ptr cinfo, int marker,
 130                                       unsigned int datalen));
 131   JMETHOD(void, write_marker_byte, (j_compress_ptr cinfo, int val));
 132 };
 133
 134
 135 /* Declarations for decompression modules */
 136
 137 /* Master control module */
 138 struct jpeg_decomp_master {
 139   JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo));
 140   JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo));
 141
 142   /* State variables made visible to other modules */
 143   boolean is_dummy_pass;        /* True during 1st pass for 2-pass quant */
 144 };
 145
 146 /* Input control module */
 147 struct jpeg_input_controller {
 148   JMETHOD(int, consume_input, (j_decompress_ptr cinfo));
 149   JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo));
 150   JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
 151   JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo));
 152
 153   /* State variables made visible to other modules */
 154   boolean has_multiple_scans;   /* True if file has multiple scans */
 155   boolean eoi_reached;          /* True when EOI has been consumed */
 156 };
 157
 158 /* Main buffer control (downsampled-data buffer) */
 159 struct jpeg_d_main_controller {
 160   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
 161   JMETHOD(void, process_data, (j_decompress_ptr cinfo,
 162                                JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
 163                                JDIMENSION out_rows_avail));
 164 };
 165
 166 /* Coefficient buffer control */
 167 struct jpeg_d_coef_controller {
 168   JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
 169   JMETHOD(int, consume_data, (j_decompress_ptr cinfo));
 170   JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo));
 171   JMETHOD(int, decompress_data, (j_decompress_ptr cinfo,
 172                                  JSAMPIMAGE output_buf));
 173   /* Pointer to array of coefficient virtual arrays, or NULL if none */
 174   jvirt_barray_ptr *coef_arrays;
 175 };
 176
 177 /* Decompression postprocessing (color quantization buffer control) */
 178 struct jpeg_d_post_controller {
 179   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
 180   JMETHOD(void, post_process_data, (j_decompress_ptr cinfo,
 181                                     JSAMPIMAGE input_buf,
 182                                     JDIMENSION *in_row_group_ctr,
 183                                     JDIMENSION in_row_groups_avail,
 184                                     JSAMPARRAY output_buf,
 185                                     JDIMENSION *out_row_ctr,
 186                                     JDIMENSION out_rows_avail));
 187 };
 188
 189 /* Marker reading & parsing */
 190 struct jpeg_marker_reader {
 191   JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo));
 192   /* Read markers until SOS or EOI.
 193    * Returns same codes as are defined for jpeg_consume_input:
 194    * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
 195    */
 196   JMETHOD(int, read_markers, (j_decompress_ptr cinfo));
 197   /* Read a restart marker --- exported for use by entropy decoder only */
 198   jpeg_marker_parser_method read_restart_marker;
 199
 200   /* State of marker reader --- nominally internal, but applications
 201    * supplying COM or APPn handlers might like to know the state.
 202    */
 203   boolean saw_SOI;              /* found SOI? */
 204   boolean saw_SOF;              /* found SOF? */
 205   int next_restart_num;         /* next restart number expected (0-7) */
 206   unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */
 207 };
 208
 209 /* Entropy decoding */
 210 struct jpeg_entropy_decoder {
 211   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
 212   JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo,
 213                                 JBLOCKROW *MCU_data));
 214
 215   /* This is here to share code between baseline and progressive decoders; */
 216   /* other modules probably should not use it */
 217   boolean insufficient_data;    /* set TRUE after emitting warning */
 218 };
 219
 220 /* Inverse DCT (also performs dequantization) */
 221 typedef JMETHOD(void, inverse_DCT_method_ptr,
 222                 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
 223                  JCOEFPTR coef_block,
 224                  JSAMPARRAY output_buf, JDIMENSION output_col));
 225
 226 struct jpeg_inverse_dct {
 227   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
 228   /* It is useful to allow each component to have a separate IDCT method. */
 229   inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS];
 230 };
 231
 232 /* Upsampling (note that upsampler must also call color converter) */
 233 struct jpeg_upsampler {
 234   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
 235   JMETHOD(void, upsample, (j_decompress_ptr cinfo,
 236                            JSAMPIMAGE input_buf,
 237                            JDIMENSION *in_row_group_ctr,
 238                            JDIMENSION in_row_groups_avail,
 239                            JSAMPARRAY output_buf,
 240                            JDIMENSION *out_row_ctr,
 241                            JDIMENSION out_rows_avail));
 242
 243   boolean need_context_rows;    /* TRUE if need rows above & below */
 244 };
 245
 246 /* Colorspace conversion */
 247 struct jpeg_color_deconverter {
 248   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
 249   JMETHOD(void, color_convert, (j_decompress_ptr cinfo,
 250                                 JSAMPIMAGE input_buf, JDIMENSION input_row,
 251                                 JSAMPARRAY output_buf, int num_rows));
 252 };
 253
 254 /* Color quantization or color precision reduction */
 255 struct jpeg_color_quantizer {
 256   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan));
 257   JMETHOD(void, color_quantize, (j_decompress_ptr cinfo,
 258                                  JSAMPARRAY input_buf, JSAMPARRAY output_buf,
 259                                  int num_rows));
 260   JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));
 261   JMETHOD(void, new_color_map, (j_decompress_ptr cinfo));
 262 };
 263
 264
 265 /* Miscellaneous useful macros */
 266
 267 #undef MAX
 268 #define MAX(a,b)        ((a) > (b) ? (a) : (b))
 269 #undef MIN
 270 #define MIN(a,b)        ((a) < (b) ? (a) : (b))
 271
 272
 273 /* We assume that right shift corresponds to signed division by 2 with
 274  * rounding towards minus infinity.  This is correct for typical "arithmetic
 275  * shift" instructions that shift in copies of the sign bit.  But some
 276  * C compilers implement >> with an unsigned shift.  For these machines you
 277  * must define RIGHT_SHIFT_IS_UNSIGNED.
 278  * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity.
 279  * It is only applied with constant shift counts.  SHIFT_TEMPS must be
 280  * included in the variables of any routine using RIGHT_SHIFT.
 281  */
 282
 283 #ifdef RIGHT_SHIFT_IS_UNSIGNED
 284 #define SHIFT_TEMPS     INT32 shift_temp;
 285 #define RIGHT_SHIFT(x,shft)  \
 286         ((shift_temp = (x)) < 0 ? \
 287          (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \
 288          (shift_temp >> (shft)))
 289 #else
 290 #define SHIFT_TEMPS
 291 #define RIGHT_SHIFT(x,shft)     ((x) >> (shft))
 292 #endif
 293
 294
 295 /* Short forms of external names for systems with brain-damaged linkers. */
 296
 297 #ifdef NEED_SHORT_EXTERNAL_NAMES
 298 #define jinit_compress_master   jICompress
 299 #define jinit_c_master_control  jICMaster
 300 #define jinit_c_main_controller jICMainC
 301 #define jinit_c_prep_controller jICPrepC
 302 #define jinit_c_coef_controller jICCoefC
 303 #define jinit_color_converter   jICColor
 304 #define jinit_downsampler       jIDownsampler
 305 #define jinit_forward_dct       jIFDCT
 306 #define jinit_huff_encoder      jIHEncoder
 307 #define jinit_phuff_encoder     jIPHEncoder
 308 #define jinit_arith_encoder     jIAEncoder
 309 #define jinit_marker_writer     jIMWriter
 310 #define jinit_master_decompress jIDMaster
 311 #define jinit_d_main_controller jIDMainC
 312 #define jinit_d_coef_controller jIDCoefC
 313 #define jinit_d_post_controller jIDPostC
 314 #define jinit_input_controller  jIInCtlr
 315 #define jinit_marker_reader     jIMReader
 316 #define jinit_huff_decoder      jIHDecoder
 317 #define jinit_phuff_decoder     jIPHDecoder
 318 #define jinit_arith_decoder     jIADecoder
 319 #define jinit_inverse_dct       jIIDCT
 320 #define jinit_upsampler         jIUpsampler
 321 #define jinit_color_deconverter jIDColor
 322 #define jinit_1pass_quantizer   jI1Quant
 323 #define jinit_2pass_quantizer   jI2Quant
 324 #define jinit_merged_upsampler  jIMUpsampler
 325 #define jinit_memory_mgr        jIMemMgr
 326 #define jdiv_round_up           jDivRound
 327 #define jround_up               jRound
 328 #define jcopy_sample_rows       jCopySamples
 329 #define jcopy_block_row         jCopyBlocks
 330 #define jzero_far               jZeroFar
 331 #define jpeg_zigzag_order       jZIGTable
 332 #define jpeg_natural_order      jZAGTable
 333 #define jpeg_aritab             jAriTab
 334 #endif /* NEED_SHORT_EXTERNAL_NAMES */
 335
 336
 337 /* Compression module initialization routines */
 338 EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
 339 EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
 340                                          boolean transcode_only));
 341 EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
 342                                           boolean need_full_buffer));
 343 EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
 344                                           boolean need_full_buffer));
 345 EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
 346                                           boolean need_full_buffer));
 347 EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
 348 EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
 349 EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
 350 EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
 351 EXTERN(void) jinit_phuff_encoder JPP((j_compress_ptr cinfo));
 352 EXTERN(void) jinit_arith_encoder JPP((j_compress_ptr cinfo));
 353 EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
 354 /* Decompression module initialization routines */
 355 EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
 356 EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
 357                                           boolean need_full_buffer));
 358 EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
 359                                           boolean need_full_buffer));
 360 EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
 361                                           boolean need_full_buffer));
 362 EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
 363 EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
 364 EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
 365 EXTERN(void) jinit_phuff_decoder JPP((j_decompress_ptr cinfo));
 366 EXTERN(void) jinit_arith_decoder JPP((j_decompress_ptr cinfo));
 367 EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo));
 368 EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo));
 369 EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo));
 370 EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));
 371 EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));
 372 EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo));
 373 /* Memory manager initialization */
 374 EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo));
 375
 376 /* Utility routines in jutils.c */
 377 EXTERN(long) jdiv_round_up JPP((long a, long b));
 378 EXTERN(long) jround_up JPP((long a, long b));
 379 EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row,
 380                                     JSAMPARRAY output_array, int dest_row,
 381                                     int num_rows, JDIMENSION num_cols));
 382 EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,
 383                                   JDIMENSION num_blocks));
 384 EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero));
 385 /* Constant tables in jutils.c */
 386 #if 0                           /* This table is not actually needed in v6a */
 387 extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
 388 #endif
 389 extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
 390
 391 /* Arithmetic coding probability estimation tables in jaricom.c */
 392 extern const INT32 jpeg_aritab[];
 393
 394 /* Suppress undefined-structure complaints if necessary. */
 395
 396 #ifdef INCOMPLETE_TYPES_BROKEN
 397 #ifndef AM_MEMORY_MANAGER       /* only jmemmgr.c defines these */
 398 struct jvirt_sarray_control { long dummy; };
 399 struct jvirt_barray_control { long dummy; };
 400 #endif
 401 #endif /* INCOMPLETE_TYPES_BROKEN */