1 /*
   2  * jpegint.h
   3  *
   4  * Copyright (C) 1991-1997, Thomas G. Lane.
   5  * Modified 1997-2017 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 typedef JMETHOD(void, forward_DCT_ptr,
 104                 (j_compress_ptr cinfo, jpeg_component_info * compptr,
 105                  JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
 106                  JDIMENSION start_row, JDIMENSION start_col,
 107                  JDIMENSION num_blocks));
 108 
 109 struct jpeg_forward_dct {
 110   JMETHOD(void, start_pass, (j_compress_ptr cinfo));
 111   /* It is useful to allow each component to have a separate FDCT method. */
 112   forward_DCT_ptr forward_DCT[MAX_COMPONENTS];
 113 };
 114 
 115 /* Entropy encoding */
 116 struct jpeg_entropy_encoder {
 117   JMETHOD(void, start_pass, (j_compress_ptr cinfo, boolean gather_statistics));
 118   JMETHOD(boolean, encode_mcu, (j_compress_ptr cinfo, JBLOCKROW *MCU_data));
 119   JMETHOD(void, finish_pass, (j_compress_ptr cinfo));
 120 };
 121 
 122 /* Marker writing */
 123 struct jpeg_marker_writer {
 124   JMETHOD(void, write_file_header, (j_compress_ptr cinfo));
 125   JMETHOD(void, write_frame_header, (j_compress_ptr cinfo));
 126   JMETHOD(void, write_scan_header, (j_compress_ptr cinfo));
 127   JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo));
 128   JMETHOD(void, write_tables_only, (j_compress_ptr cinfo));
 129   /* These routines are exported to allow insertion of extra markers */
 130   /* Probably only COM and APPn markers should be written this way */
 131   JMETHOD(void, write_marker_header, (j_compress_ptr cinfo, int marker,
 132                                       unsigned int datalen));
 133   JMETHOD(void, write_marker_byte, (j_compress_ptr cinfo, int val));
 134 };
 135 
 136 
 137 /* Declarations for decompression modules */
 138 
 139 /* Master control module */
 140 struct jpeg_decomp_master {
 141   JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo));
 142   JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo));
 143 
 144   /* State variables made visible to other modules */
 145   boolean is_dummy_pass;        /* True during 1st pass for 2-pass quant */
 146 };
 147 
 148 /* Input control module */
 149 struct jpeg_input_controller {
 150   JMETHOD(int, consume_input, (j_decompress_ptr cinfo));
 151   JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo));
 152   JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
 153   JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo));
 154 
 155   /* State variables made visible to other modules */
 156   boolean has_multiple_scans;   /* True if file has multiple scans */
 157   boolean eoi_reached;          /* True when EOI has been consumed */
 158 };
 159 
 160 /* Main buffer control (downsampled-data buffer) */
 161 struct jpeg_d_main_controller {
 162   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
 163   JMETHOD(void, process_data, (j_decompress_ptr cinfo,
 164                                JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
 165                                JDIMENSION out_rows_avail));
 166 };
 167 
 168 /* Coefficient buffer control */
 169 struct jpeg_d_coef_controller {
 170   JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
 171   JMETHOD(int, consume_data, (j_decompress_ptr cinfo));
 172   JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo));
 173   JMETHOD(int, decompress_data, (j_decompress_ptr cinfo,
 174                                  JSAMPIMAGE output_buf));
 175   /* Pointer to array of coefficient virtual arrays, or NULL if none */
 176   jvirt_barray_ptr *coef_arrays;
 177 };
 178 
 179 /* Decompression postprocessing (color quantization buffer control) */
 180 struct jpeg_d_post_controller {
 181   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
 182   JMETHOD(void, post_process_data, (j_decompress_ptr cinfo,
 183                                     JSAMPIMAGE input_buf,
 184                                     JDIMENSION *in_row_group_ctr,
 185                                     JDIMENSION in_row_groups_avail,
 186                                     JSAMPARRAY output_buf,
 187                                     JDIMENSION *out_row_ctr,
 188                                     JDIMENSION out_rows_avail));
 189 };
 190 
 191 /* Marker reading & parsing */
 192 struct jpeg_marker_reader {
 193   JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo));
 194   /* Read markers until SOS or EOI.
 195    * Returns same codes as are defined for jpeg_consume_input:
 196    * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
 197    */
 198   JMETHOD(int, read_markers, (j_decompress_ptr cinfo));
 199   /* Read a restart marker --- exported for use by entropy decoder only */
 200   jpeg_marker_parser_method read_restart_marker;
 201 
 202   /* State of marker reader --- nominally internal, but applications
 203    * supplying COM or APPn handlers might like to know the state.
 204    */
 205   boolean saw_SOI;              /* found SOI? */
 206   boolean saw_SOF;              /* found SOF? */
 207   int next_restart_num;         /* next restart number expected (0-7) */
 208   unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */
 209 };
 210 
 211 /* Entropy decoding */
 212 struct jpeg_entropy_decoder {
 213   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
 214   JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo, JBLOCKROW *MCU_data));
 215   JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));
 216 };
 217 
 218 /* Inverse DCT (also performs dequantization) */
 219 typedef JMETHOD(void, inverse_DCT_method_ptr,
 220                 (j_decompress_ptr cinfo, jpeg_component_info * compptr,
 221                  JCOEFPTR coef_block,
 222                  JSAMPARRAY output_buf, JDIMENSION output_col));
 223 
 224 struct jpeg_inverse_dct {
 225   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
 226   /* It is useful to allow each component to have a separate IDCT method. */
 227   inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS];
 228 };
 229 
 230 /* Upsampling (note that upsampler must also call color converter) */
 231 struct jpeg_upsampler {
 232   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
 233   JMETHOD(void, upsample, (j_decompress_ptr cinfo,
 234                            JSAMPIMAGE input_buf,
 235                            JDIMENSION *in_row_group_ctr,
 236                            JDIMENSION in_row_groups_avail,
 237                            JSAMPARRAY output_buf,
 238                            JDIMENSION *out_row_ctr,
 239                            JDIMENSION out_rows_avail));
 240 
 241   boolean need_context_rows;    /* TRUE if need rows above & below */
 242 };
 243 
 244 /* Colorspace conversion */
 245 struct jpeg_color_deconverter {
 246   JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
 247   JMETHOD(void, color_convert, (j_decompress_ptr cinfo,
 248                                 JSAMPIMAGE input_buf, JDIMENSION input_row,
 249                                 JSAMPARRAY output_buf, int num_rows));
 250 };
 251 
 252 /* Color quantization or color precision reduction */
 253 struct jpeg_color_quantizer {
 254   JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan));
 255   JMETHOD(void, color_quantize, (j_decompress_ptr cinfo,
 256                                  JSAMPARRAY input_buf, JSAMPARRAY output_buf,
 257                                  int num_rows));
 258   JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));
 259   JMETHOD(void, new_color_map, (j_decompress_ptr cinfo));
 260 };
 261 
 262 
 263 /* Definition of range extension bits for decompression processes.
 264  * See the comments with prepare_range_limit_table (in jdmaster.c)
 265  * for more info.
 266  * The recommended default value for normal applications is 2.
 267  * Applications with special requirements may use a different value.
 268  * For example, Ghostscript wants to use 3 for proper handling of
 269  * wacky images with oversize coefficient values.
 270  */
 271 
 272 #define RANGE_BITS      2
 273 #define RANGE_CENTER    (CENTERJSAMPLE << RANGE_BITS)
 274 
 275 
 276 /* Miscellaneous useful macros */
 277 
 278 #undef MAX
 279 #define MAX(a,b)        ((a) > (b) ? (a) : (b))
 280 #undef MIN
 281 #define MIN(a,b)        ((a) < (b) ? (a) : (b))
 282 
 283 
 284 /* We assume that right shift corresponds to signed division by 2 with
 285  * rounding towards minus infinity.  This is correct for typical "arithmetic
 286  * shift" instructions that shift in copies of the sign bit.  But some
 287  * C compilers implement >> with an unsigned shift.  For these machines you
 288  * must define RIGHT_SHIFT_IS_UNSIGNED.
 289  * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity.
 290  * It is only applied with constant shift counts.  SHIFT_TEMPS must be
 291  * included in the variables of any routine using RIGHT_SHIFT.
 292  */
 293 
 294 #ifdef RIGHT_SHIFT_IS_UNSIGNED
 295 #define SHIFT_TEMPS     INT32 shift_temp;
 296 #define RIGHT_SHIFT(x,shft)  \
 297         ((shift_temp = (x)) < 0 ? \
 298          (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \
 299          (shift_temp >> (shft)))
 300 #else
 301 #define SHIFT_TEMPS
 302 #define RIGHT_SHIFT(x,shft)     ((x) >> (shft))
 303 #endif
 304 
 305 
 306 /* Short forms of external names for systems with brain-damaged linkers. */
 307 
 308 #ifdef NEED_SHORT_EXTERNAL_NAMES
 309 #define jinit_compress_master   jICompress
 310 #define jinit_c_master_control  jICMaster
 311 #define jinit_c_main_controller jICMainC
 312 #define jinit_c_prep_controller jICPrepC
 313 #define jinit_c_coef_controller jICCoefC
 314 #define jinit_color_converter   jICColor
 315 #define jinit_downsampler       jIDownsampler
 316 #define jinit_forward_dct       jIFDCT
 317 #define jinit_huff_encoder      jIHEncoder
 318 #define jinit_arith_encoder     jIAEncoder
 319 #define jinit_marker_writer     jIMWriter
 320 #define jinit_master_decompress jIDMaster
 321 #define jinit_d_main_controller jIDMainC
 322 #define jinit_d_coef_controller jIDCoefC
 323 #define jinit_d_post_controller jIDPostC
 324 #define jinit_input_controller  jIInCtlr
 325 #define jinit_marker_reader     jIMReader
 326 #define jinit_huff_decoder      jIHDecoder
 327 #define jinit_arith_decoder     jIADecoder
 328 #define jinit_inverse_dct       jIIDCT
 329 #define jinit_upsampler         jIUpsampler
 330 #define jinit_color_deconverter jIDColor
 331 #define jinit_1pass_quantizer   jI1Quant
 332 #define jinit_2pass_quantizer   jI2Quant
 333 #define jinit_merged_upsampler  jIMUpsampler
 334 #define jinit_memory_mgr        jIMemMgr
 335 #define jdiv_round_up           jDivRound
 336 #define jround_up               jRound
 337 #define jzero_far               jZeroFar
 338 #define jcopy_sample_rows       jCopySamples
 339 #define jcopy_block_row         jCopyBlocks
 340 #define jpeg_zigzag_order       jZIGTable
 341 #define jpeg_natural_order      jZAGTable
 342 #define jpeg_natural_order7     jZAG7Table
 343 #define jpeg_natural_order6     jZAG6Table
 344 #define jpeg_natural_order5     jZAG5Table
 345 #define jpeg_natural_order4     jZAG4Table
 346 #define jpeg_natural_order3     jZAG3Table
 347 #define jpeg_natural_order2     jZAG2Table
 348 #define jpeg_aritab             jAriTab
 349 #endif /* NEED_SHORT_EXTERNAL_NAMES */
 350 
 351 
 352 /* On normal machines we can apply MEMCOPY() and MEMZERO() to sample arrays
 353  * and coefficient-block arrays.  This won't work on 80x86 because the arrays
 354  * are FAR and we're assuming a small-pointer memory model.  However, some
 355  * DOS compilers provide far-pointer versions of memcpy() and memset() even
 356  * in the small-model libraries.  These will be used if USE_FMEM is defined.
 357  * Otherwise, the routines in jutils.c do it the hard way.
 358  */
 359 
 360 #ifndef NEED_FAR_POINTERS       /* normal case, same as regular macro */
 361 #define FMEMZERO(target,size)   MEMZERO(target,size)
 362 #else                           /* 80x86 case */
 363 #ifdef USE_FMEM
 364 #define FMEMZERO(target,size)   _fmemset((void FAR *)(target), 0, (size_t)(size))
 365 #else
 366 EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero));
 367 #define FMEMZERO(target,size)   jzero_far(target, size)
 368 #endif
 369 #endif
 370 
 371 
 372 /* Compression module initialization routines */
 373 EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
 374 EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
 375                                          boolean transcode_only));
 376 EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
 377                                           boolean need_full_buffer));
 378 EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
 379                                           boolean need_full_buffer));
 380 EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
 381                                           boolean need_full_buffer));
 382 EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
 383 EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
 384 EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
 385 EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
 386 EXTERN(void) jinit_arith_encoder JPP((j_compress_ptr cinfo));
 387 EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
 388 /* Decompression module initialization routines */
 389 EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
 390 EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
 391                                           boolean need_full_buffer));
 392 EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
 393                                           boolean need_full_buffer));
 394 EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
 395                                           boolean need_full_buffer));
 396 EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
 397 EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
 398 EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
 399 EXTERN(void) jinit_arith_decoder JPP((j_decompress_ptr cinfo));
 400 EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo));
 401 EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo));
 402 EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo));
 403 EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));
 404 EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));
 405 EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo));
 406 /* Memory manager initialization */
 407 EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo));
 408 
 409 /* Utility routines in jutils.c */
 410 EXTERN(long) jdiv_round_up JPP((long a, long b));
 411 EXTERN(long) jround_up JPP((long a, long b));
 412 EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row,
 413                                     JSAMPARRAY output_array, int dest_row,
 414                                     int num_rows, JDIMENSION num_cols));
 415 EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,
 416                                   JDIMENSION num_blocks));
 417 /* Constant tables in jutils.c */
 418 #if 0                           /* This table is not actually needed in v6a */
 419 extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
 420 #endif
 421 extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
 422 extern const int jpeg_natural_order7[]; /* zz to natural order for 7x7 block */
 423 extern const int jpeg_natural_order6[]; /* zz to natural order for 6x6 block */
 424 extern const int jpeg_natural_order5[]; /* zz to natural order for 5x5 block */
 425 extern const int jpeg_natural_order4[]; /* zz to natural order for 4x4 block */
 426 extern const int jpeg_natural_order3[]; /* zz to natural order for 3x3 block */
 427 extern const int jpeg_natural_order2[]; /* zz to natural order for 2x2 block */
 428 
 429 /* Arithmetic coding probability estimation tables in jaricom.c */
 430 extern const INT32 jpeg_aritab[];
 431 
 432 /* Suppress undefined-structure complaints if necessary. */
 433 
 434 #ifdef INCOMPLETE_TYPES_BROKEN
 435 #ifndef AM_MEMORY_MANAGER       /* only jmemmgr.c defines these */
 436 struct jvirt_sarray_control { long dummy; };
 437 struct jvirt_barray_control { long dummy; };
 438 #endif
 439 #endif /* INCOMPLETE_TYPES_BROKEN */