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      1 /*
      2  * jpegint.h
      3  *
      4  * Copyright (C) 1991-1997, Thomas G. Lane.
      5  * Modified 1997-2011 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,
    215                                 JBLOCKROW *MCU_data));
    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 /* Miscellaneous useful macros */
    264 
    265 #undef MAX
    266 #define MAX(a,b)	((a) > (b) ? (a) : (b))
    267 #undef MIN
    268 #define MIN(a,b)	((a) < (b) ? (a) : (b))
    269 
    270 
    271 /* We assume that right shift corresponds to signed division by 2 with
    272  * rounding towards minus infinity.  This is correct for typical "arithmetic
    273  * shift" instructions that shift in copies of the sign bit.  But some
    274  * C compilers implement >> with an unsigned shift.  For these machines you
    275  * must define RIGHT_SHIFT_IS_UNSIGNED.
    276  * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity.
    277  * It is only applied with constant shift counts.  SHIFT_TEMPS must be
    278  * included in the variables of any routine using RIGHT_SHIFT.
    279  */
    280 
    281 #ifdef RIGHT_SHIFT_IS_UNSIGNED
    282 #define SHIFT_TEMPS	INT32 shift_temp;
    283 #define RIGHT_SHIFT(x,shft)  \
    284         ((shift_temp = (x)) < 0 ? \
    285          (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \
    286          (shift_temp >> (shft)))
    287 #else
    288 #define SHIFT_TEMPS
    289 #define RIGHT_SHIFT(x,shft)	((x) >> (shft))
    290 #endif
    291 
    292 
    293 /* Short forms of external names for systems with brain-damaged linkers. */
    294 
    295 #ifdef NEED_SHORT_EXTERNAL_NAMES
    296 #define jinit_compress_master	jICompress
    297 #define jinit_c_master_control	jICMaster
    298 #define jinit_c_main_controller	jICMainC
    299 #define jinit_c_prep_controller	jICPrepC
    300 #define jinit_c_coef_controller	jICCoefC
    301 #define jinit_color_converter	jICColor
    302 #define jinit_downsampler	jIDownsampler
    303 #define jinit_forward_dct	jIFDCT
    304 #define jinit_huff_encoder	jIHEncoder
    305 #define jinit_arith_encoder	jIAEncoder
    306 #define jinit_marker_writer	jIMWriter
    307 #define jinit_master_decompress	jIDMaster
    308 #define jinit_d_main_controller	jIDMainC
    309 #define jinit_d_coef_controller	jIDCoefC
    310 #define jinit_d_post_controller	jIDPostC
    311 #define jinit_input_controller	jIInCtlr
    312 #define jinit_marker_reader	jIMReader
    313 #define jinit_huff_decoder	jIHDecoder
    314 #define jinit_arith_decoder	jIADecoder
    315 #define jinit_inverse_dct	jIIDCT
    316 #define jinit_upsampler		jIUpsampler
    317 #define jinit_color_deconverter	jIDColor
    318 #define jinit_1pass_quantizer	jI1Quant
    319 #define jinit_2pass_quantizer	jI2Quant
    320 #define jinit_merged_upsampler	jIMUpsampler
    321 #define jinit_memory_mgr	jIMemMgr
    322 #define jdiv_round_up		jDivRound
    323 #define jround_up		jRound
    324 #define jzero_far		jZeroFar
    325 #define jcopy_sample_rows	jCopySamples
    326 #define jcopy_block_row		jCopyBlocks
    327 #define jpeg_zigzag_order	jZIGTable
    328 #define jpeg_natural_order	jZAGTable
    329 #define jpeg_natural_order7	jZAG7Table
    330 #define jpeg_natural_order6	jZAG6Table
    331 #define jpeg_natural_order5	jZAG5Table
    332 #define jpeg_natural_order4	jZAG4Table
    333 #define jpeg_natural_order3	jZAG3Table
    334 #define jpeg_natural_order2	jZAG2Table
    335 #define jpeg_aritab		jAriTab
    336 #endif /* NEED_SHORT_EXTERNAL_NAMES */
    337 
    338 
    339 /* On normal machines we can apply MEMCOPY() and MEMZERO() to sample arrays
    340  * and coefficient-block arrays.  This won't work on 80x86 because the arrays
    341  * are FAR and we're assuming a small-pointer memory model.  However, some
    342  * DOS compilers provide far-pointer versions of memcpy() and memset() even
    343  * in the small-model libraries.  These will be used if USE_FMEM is defined.
    344  * Otherwise, the routines in jutils.c do it the hard way.
    345  */
    346 
    347 #ifndef NEED_FAR_POINTERS	/* normal case, same as regular macro */
    348 #define FMEMZERO(target,size)	MEMZERO(target,size)
    349 #else				/* 80x86 case */
    350 #ifdef USE_FMEM
    351 #define FMEMZERO(target,size)	_fmemset((void FAR *)(target), 0, (size_t)(size))
    352 #else
    353 EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero));
    354 #define FMEMZERO(target,size)	jzero_far(target, size)
    355 #endif
    356 #endif
    357 
    358 
    359 /* Compression module initialization routines */
    360 EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
    361 EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
    362                                          boolean transcode_only));
    363 EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
    364                                           boolean need_full_buffer));
    365 EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
    366                                           boolean need_full_buffer));
    367 EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
    368                                           boolean need_full_buffer));
    369 EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
    370 EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
    371 EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
    372 EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
    373 EXTERN(void) jinit_arith_encoder JPP((j_compress_ptr cinfo));
    374 EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
    375 /* Decompression module initialization routines */
    376 EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
    377 EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
    378                                           boolean need_full_buffer));
    379 EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
    380                                           boolean need_full_buffer));
    381 EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
    382                                           boolean need_full_buffer));
    383 EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
    384 EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
    385 EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
    386 EXTERN(void) jinit_arith_decoder JPP((j_decompress_ptr cinfo));
    387 EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo));
    388 EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo));
    389 EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo));
    390 EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));
    391 EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));
    392 EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo));
    393 /* Memory manager initialization */
    394 EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo));
    395 
    396 /* Utility routines in jutils.c */
    397 EXTERN(long) jdiv_round_up JPP((long a, long b));
    398 EXTERN(long) jround_up JPP((long a, long b));
    399 EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row,
    400                                     JSAMPARRAY output_array, int dest_row,
    401                                     int num_rows, JDIMENSION num_cols));
    402 EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,
    403                                   JDIMENSION num_blocks));
    404 /* Constant tables in jutils.c */
    405 #if 0				/* This table is not actually needed in v6a */
    406 extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
    407 #endif
    408 extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
    409 extern const int jpeg_natural_order7[]; /* zz to natural order for 7x7 block */
    410 extern const int jpeg_natural_order6[]; /* zz to natural order for 6x6 block */
    411 extern const int jpeg_natural_order5[]; /* zz to natural order for 5x5 block */
    412 extern const int jpeg_natural_order4[]; /* zz to natural order for 4x4 block */
    413 extern const int jpeg_natural_order3[]; /* zz to natural order for 3x3 block */
    414 extern const int jpeg_natural_order2[]; /* zz to natural order for 2x2 block */
    415 
    416 /* Arithmetic coding probability estimation tables in jaricom.c */
    417 extern const INT32 jpeg_aritab[];
    418 
    419 /* Suppress undefined-structure complaints if necessary. */
    420 
    421 #ifdef INCOMPLETE_TYPES_BROKEN
    422 #ifndef AM_MEMORY_MANAGER	/* only jmemmgr.c defines these */
    423 struct jvirt_sarray_control { long dummy; };
    424 struct jvirt_barray_control { long dummy; };
    425 #endif
    426 #endif /* INCOMPLETE_TYPES_BROKEN */
    427