text: /*
   * jpegint.h
   *
   * Copyright (C) 1991-1997, Thomas G. Lane.
   * Modified 1997-2009 by Guido Vollbeding.
   * This file is part of the Independent JPEG Group's software.
   * For conditions of distribution and use, see the accompanying README file.
   *
   * This file provides common declarations for the various JPEG modules.
   * These declarations are considered internal to the JPEG library; most
   * applications using the library shouldn't need to include this file.
   */
  
  
  /* Declarations for both compression & decompression */
  
  typedef enum {            /* Operating modes for buffer controllers */
    JBUF_PASS_THRU,         /* Plain stripwise operation */
    /* Remaining modes require a full-image buffer to have been created */
    JBUF_SAVE_SOURCE,       /* Run source subobject only, save output */
    JBUF_CRANK_DEST,        /* Run dest subobject only, using saved data */
    JBUF_SAVE_AND_PASS      /* Run both subobjects, save output */
  } J_BUF_MODE;
  
  /* Values of global_state field (jdapi.c has some dependencies on ordering!) */
  #define CSTATE_START    100     /* after create_compress */
  #define CSTATE_SCANNING 101     /* start_compress done, write_scanlines OK */
  #define CSTATE_RAW_OK   102     /* start_compress done, write_raw_data OK */
  #define CSTATE_WRCOEFS  103     /* jpeg_write_coefficients done */
  #define DSTATE_START    200     /* after create_decompress */
  #define DSTATE_INHEADER 201     /* reading header markers, no SOS yet */
  #define DSTATE_READY    202     /* found SOS, ready for start_decompress */
  #define DSTATE_PRELOAD  203     /* reading multiscan file in start_decompress*/
  #define DSTATE_PRESCAN  204     /* performing dummy pass for 2-pass quant */
  #define DSTATE_SCANNING 205     /* start_decompress done, read_scanlines OK */
  #define DSTATE_RAW_OK   206     /* start_decompress done, read_raw_data OK */
  #define DSTATE_BUFIMAGE 207     /* expecting jpeg_start_output */
  #define DSTATE_BUFPOST  208     /* looking for SOS/EOI in jpeg_finish_output */
  #define DSTATE_RDCOEFS  209     /* reading file in jpeg_read_coefficients */
  #define DSTATE_STOPPING 210     /* looking for EOI in jpeg_finish_decompress */
  
  
  /* Declarations for compression modules */
  
  /* Master control module */
  struct jpeg_comp_master {
    JMETHOD(void, prepare_for_pass, (j_compress_ptr cinfo));
    JMETHOD(void, pass_startup, (j_compress_ptr cinfo));
    JMETHOD(void, finish_pass, (j_compress_ptr cinfo));
  
    /* State variables made visible to other modules */
    boolean call_pass_startup;    /* True if pass_startup must be called */
    boolean is_last_pass;         /* True during last pass */
  };
  
  /* Main buffer control (downsampled-data buffer) */
  struct jpeg_c_main_controller {
    JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
    JMETHOD(void, process_data, (j_compress_ptr cinfo,
                                 JSAMPARRAY input_buf, JDIMENSION *in_row_ctr,
                                 JDIMENSION in_rows_avail));
  };
  
  /* Compression preprocessing (downsampling input buffer control) */
  struct jpeg_c_prep_controller {
    JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
    JMETHOD(void, pre_process_data, (j_compress_ptr cinfo,
                                     JSAMPARRAY input_buf,
                                     JDIMENSION *in_row_ctr,
                                     JDIMENSION in_rows_avail,
                                     JSAMPIMAGE output_buf,
                                     JDIMENSION *out_row_group_ctr,
                                     JDIMENSION out_row_groups_avail));
  };
  
  /* Coefficient buffer control */
  struct jpeg_c_coef_controller {
    JMETHOD(void, start_pass, (j_compress_ptr cinfo, J_BUF_MODE pass_mode));
    JMETHOD(boolean, compress_data, (j_compress_ptr cinfo,
                                     JSAMPIMAGE input_buf));
  };
  
  /* Colorspace conversion */
  struct jpeg_color_converter {
    JMETHOD(void, start_pass, (j_compress_ptr cinfo));
    JMETHOD(void, color_convert, (j_compress_ptr cinfo,
                                  JSAMPARRAY input_buf, JSAMPIMAGE output_buf,
                                  JDIMENSION output_row, int num_rows));
  };
  
  /* Downsampling */
  struct jpeg_downsampler {
    JMETHOD(void, start_pass, (j_compress_ptr cinfo));
    JMETHOD(void, downsample, (j_compress_ptr cinfo,
                               JSAMPIMAGE input_buf, JDIMENSION in_row_index,
                               JSAMPIMAGE output_buf,
                               JDIMENSION out_row_group_index));
  
    boolean need_context_rows;    /* TRUE if need rows above & below */
  };
  
  /* Forward DCT (also controls coefficient quantization) */
  struct jpeg_forward_dct {
    JMETHOD(void, start_pass, (j_compress_ptr cinfo));
    /* perhaps this should be an array??? */
    JMETHOD(void, forward_DCT, (j_compress_ptr cinfo,
                                jpeg_component_info * compptr,
                                JSAMPARRAY sample_data, JBLOCKROW coef_blocks,
                                JDIMENSION start_row, JDIMENSION start_col,
                                JDIMENSION num_blocks));
  };
  
  /* Entropy encoding */
  struct jpeg_entropy_encoder {
    JMETHOD(void, start_pass, (j_compress_ptr cinfo, boolean gather_statistics));
    JMETHOD(boolean, encode_mcu, (j_compress_ptr cinfo, JBLOCKROW *MCU_data));
    JMETHOD(void, finish_pass, (j_compress_ptr cinfo));
  };
  
  /* Marker writing */
  struct jpeg_marker_writer {
    JMETHOD(void, write_file_header, (j_compress_ptr cinfo));
    JMETHOD(void, write_frame_header, (j_compress_ptr cinfo));
    JMETHOD(void, write_scan_header, (j_compress_ptr cinfo));
    JMETHOD(void, write_file_trailer, (j_compress_ptr cinfo));
    JMETHOD(void, write_tables_only, (j_compress_ptr cinfo));
    /* These routines are exported to allow insertion of extra markers */
    /* Probably only COM and APPn markers should be written this way */
    JMETHOD(void, write_marker_header, (j_compress_ptr cinfo, int marker,
                                        unsigned int datalen));
    JMETHOD(void, write_marker_byte, (j_compress_ptr cinfo, int val));
  };
  
  
  /* Declarations for decompression modules */
  
  /* Master control module */
  struct jpeg_decomp_master {
    JMETHOD(void, prepare_for_output_pass, (j_decompress_ptr cinfo));
    JMETHOD(void, finish_output_pass, (j_decompress_ptr cinfo));
  
    /* State variables made visible to other modules */
    boolean is_dummy_pass;        /* True during 1st pass for 2-pass quant */
  };
  
  /* Input control module */
  struct jpeg_input_controller {
    JMETHOD(int, consume_input, (j_decompress_ptr cinfo));
    JMETHOD(void, reset_input_controller, (j_decompress_ptr cinfo));
    JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
    JMETHOD(void, finish_input_pass, (j_decompress_ptr cinfo));
  
    /* State variables made visible to other modules */
    boolean has_multiple_scans;   /* True if file has multiple scans */
    boolean eoi_reached;          /* True when EOI has been consumed */
  };
  
  /* Main buffer control (downsampled-data buffer) */
  struct jpeg_d_main_controller {
    JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
    JMETHOD(void, process_data, (j_decompress_ptr cinfo,
                                 JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
                                 JDIMENSION out_rows_avail));
  };
  
  /* Coefficient buffer control */
  struct jpeg_d_coef_controller {
    JMETHOD(void, start_input_pass, (j_decompress_ptr cinfo));
    JMETHOD(int, consume_data, (j_decompress_ptr cinfo));
    JMETHOD(void, start_output_pass, (j_decompress_ptr cinfo));
    JMETHOD(int, decompress_data, (j_decompress_ptr cinfo,
                                   JSAMPIMAGE output_buf));
    /* Pointer to array of coefficient virtual arrays, or NULL if none */
    jvirt_barray_ptr *coef_arrays;
  };
  
  /* Decompression postprocessing (color quantization buffer control) */
  struct jpeg_d_post_controller {
    JMETHOD(void, start_pass, (j_decompress_ptr cinfo, J_BUF_MODE pass_mode));
    JMETHOD(void, post_process_data, (j_decompress_ptr cinfo,
                                      JSAMPIMAGE input_buf,
                                      JDIMENSION *in_row_group_ctr,
                                      JDIMENSION in_row_groups_avail,
                                      JSAMPARRAY output_buf,
                                      JDIMENSION *out_row_ctr,
                                      JDIMENSION out_rows_avail));
  };
  
  /* Marker reading & parsing */
  struct jpeg_marker_reader {
    JMETHOD(void, reset_marker_reader, (j_decompress_ptr cinfo));
    /* Read markers until SOS or EOI.
     * Returns same codes as are defined for jpeg_consume_input:
     * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
     */
    JMETHOD(int, read_markers, (j_decompress_ptr cinfo));
    /* Read a restart marker --- exported for use by entropy decoder only */
    jpeg_marker_parser_method read_restart_marker;
  
    /* State of marker reader --- nominally internal, but applications
     * supplying COM or APPn handlers might like to know the state.
     */
    boolean saw_SOI;              /* found SOI? */
    boolean saw_SOF;              /* found SOF? */
    int next_restart_num;         /* next restart number expected (0-7) */
    unsigned int discarded_bytes; /* # of bytes skipped looking for a marker */
  };
  
  /* Entropy decoding */
  struct jpeg_entropy_decoder {
    JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
    JMETHOD(boolean, decode_mcu, (j_decompress_ptr cinfo,
                                  JBLOCKROW *MCU_data));
  
    /* This is here to share code between baseline and progressive decoders; */
    /* other modules probably should not use it */
    boolean insufficient_data;    /* set TRUE after emitting warning */
  };
  
  /* Inverse DCT (also performs dequantization) */
  typedef JMETHOD(void, inverse_DCT_method_ptr,
                  (j_decompress_ptr cinfo, jpeg_component_info * compptr,
                   JCOEFPTR coef_block,
                   JSAMPARRAY output_buf, JDIMENSION output_col));
  
  struct jpeg_inverse_dct {
    JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
    /* It is useful to allow each component to have a separate IDCT method. */
    inverse_DCT_method_ptr inverse_DCT[MAX_COMPONENTS];
  };
  
  /* Upsampling (note that upsampler must also call color converter) */
  struct jpeg_upsampler {
    JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
    JMETHOD(void, upsample, (j_decompress_ptr cinfo,
                             JSAMPIMAGE input_buf,
                             JDIMENSION *in_row_group_ctr,
                             JDIMENSION in_row_groups_avail,
                             JSAMPARRAY output_buf,
                             JDIMENSION *out_row_ctr,
                             JDIMENSION out_rows_avail));
  
    boolean need_context_rows;    /* TRUE if need rows above & below */
  };
  
  /* Colorspace conversion */
  struct jpeg_color_deconverter {
    JMETHOD(void, start_pass, (j_decompress_ptr cinfo));
    JMETHOD(void, color_convert, (j_decompress_ptr cinfo,
                                  JSAMPIMAGE input_buf, JDIMENSION input_row,
                                  JSAMPARRAY output_buf, int num_rows));
  };
  
  /* Color quantization or color precision reduction */
  struct jpeg_color_quantizer {
    JMETHOD(void, start_pass, (j_decompress_ptr cinfo, boolean is_pre_scan));
    JMETHOD(void, color_quantize, (j_decompress_ptr cinfo,
                                   JSAMPARRAY input_buf, JSAMPARRAY output_buf,
                                   int num_rows));
    JMETHOD(void, finish_pass, (j_decompress_ptr cinfo));
    JMETHOD(void, new_color_map, (j_decompress_ptr cinfo));
  };
  
  
  /* Miscellaneous useful macros */
  
  #undef MAX
  #define MAX(a,b)        ((a) > (b) ? (a) : (b))
  #undef MIN
  #define MIN(a,b)        ((a) < (b) ? (a) : (b))
  
  
  /* We assume that right shift corresponds to signed division by 2 with
   * rounding towards minus infinity.  This is correct for typical "arithmetic
   * shift" instructions that shift in copies of the sign bit.  But some
   * C compilers implement >> with an unsigned shift.  For these machines you
   * must define RIGHT_SHIFT_IS_UNSIGNED.
   * RIGHT_SHIFT provides a proper signed right shift of an INT32 quantity.
   * It is only applied with constant shift counts.  SHIFT_TEMPS must be
   * included in the variables of any routine using RIGHT_SHIFT.
   */
  
  #ifdef RIGHT_SHIFT_IS_UNSIGNED
  #define SHIFT_TEMPS     INT32 shift_temp;
  #define RIGHT_SHIFT(x,shft)  \
          ((shift_temp = (x)) < 0 ? \
           (shift_temp >> (shft)) | ((~((INT32) 0)) << (32-(shft))) : \
           (shift_temp >> (shft)))
  #else
  #define SHIFT_TEMPS
  #define RIGHT_SHIFT(x,shft)     ((x) >> (shft))
  #endif
  
  
  /* Short forms of external names for systems with brain-damaged linkers. */
  
  #ifdef NEED_SHORT_EXTERNAL_NAMES
  #define jinit_compress_master   jICompress
  #define jinit_c_master_control  jICMaster
  #define jinit_c_main_controller jICMainC
  #define jinit_c_prep_controller jICPrepC
  #define jinit_c_coef_controller jICCoefC
  #define jinit_color_converter   jICColor
  #define jinit_downsampler       jIDownsampler
  #define jinit_forward_dct       jIFDCT
  #define jinit_huff_encoder      jIHEncoder
  #define jinit_phuff_encoder     jIPHEncoder
  #define jinit_arith_encoder     jIAEncoder
  #define jinit_marker_writer     jIMWriter
  #define jinit_master_decompress jIDMaster
  #define jinit_d_main_controller jIDMainC
  #define jinit_d_coef_controller jIDCoefC
  #define jinit_d_post_controller jIDPostC
  #define jinit_input_controller  jIInCtlr
  #define jinit_marker_reader     jIMReader
  #define jinit_huff_decoder      jIHDecoder
  #define jinit_phuff_decoder     jIPHDecoder
  #define jinit_arith_decoder     jIADecoder
  #define jinit_inverse_dct       jIIDCT
  #define jinit_upsampler         jIUpsampler
  #define jinit_color_deconverter jIDColor
  #define jinit_1pass_quantizer   jI1Quant
  #define jinit_2pass_quantizer   jI2Quant
  #define jinit_merged_upsampler  jIMUpsampler
  #define jinit_memory_mgr        jIMemMgr
  #define jdiv_round_up           jDivRound
  #define jround_up               jRound
  #define jcopy_sample_rows       jCopySamples
  #define jcopy_block_row         jCopyBlocks
  #define jzero_far               jZeroFar
  #define jpeg_zigzag_order       jZIGTable
  #define jpeg_natural_order      jZAGTable
  #define jpeg_aritab             jAriTab
  #endif /* NEED_SHORT_EXTERNAL_NAMES */
  
  
  /* Compression module initialization routines */
  EXTERN(void) jinit_compress_master JPP((j_compress_ptr cinfo));
  EXTERN(void) jinit_c_master_control JPP((j_compress_ptr cinfo,
                                           boolean transcode_only));
  EXTERN(void) jinit_c_main_controller JPP((j_compress_ptr cinfo,
                                            boolean need_full_buffer));
  EXTERN(void) jinit_c_prep_controller JPP((j_compress_ptr cinfo,
                                            boolean need_full_buffer));
  EXTERN(void) jinit_c_coef_controller JPP((j_compress_ptr cinfo,
                                            boolean need_full_buffer));
  EXTERN(void) jinit_color_converter JPP((j_compress_ptr cinfo));
  EXTERN(void) jinit_downsampler JPP((j_compress_ptr cinfo));
  EXTERN(void) jinit_forward_dct JPP((j_compress_ptr cinfo));
  EXTERN(void) jinit_huff_encoder JPP((j_compress_ptr cinfo));
  EXTERN(void) jinit_phuff_encoder JPP((j_compress_ptr cinfo));
  EXTERN(void) jinit_arith_encoder JPP((j_compress_ptr cinfo));
  EXTERN(void) jinit_marker_writer JPP((j_compress_ptr cinfo));
  /* Decompression module initialization routines */
  EXTERN(void) jinit_master_decompress JPP((j_decompress_ptr cinfo));
  EXTERN(void) jinit_d_main_controller JPP((j_decompress_ptr cinfo,
                                            boolean need_full_buffer));
  EXTERN(void) jinit_d_coef_controller JPP((j_decompress_ptr cinfo,
                                            boolean need_full_buffer));
  EXTERN(void) jinit_d_post_controller JPP((j_decompress_ptr cinfo,
                                            boolean need_full_buffer));
  EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo));
  EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo));
  EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo));
  EXTERN(void) jinit_phuff_decoder JPP((j_decompress_ptr cinfo));
  EXTERN(void) jinit_arith_decoder JPP((j_decompress_ptr cinfo));
  EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo));
  EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo));
  EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo));
  EXTERN(void) jinit_1pass_quantizer JPP((j_decompress_ptr cinfo));
  EXTERN(void) jinit_2pass_quantizer JPP((j_decompress_ptr cinfo));
  EXTERN(void) jinit_merged_upsampler JPP((j_decompress_ptr cinfo));
  /* Memory manager initialization */
  EXTERN(void) jinit_memory_mgr JPP((j_common_ptr cinfo));
  
  /* Utility routines in jutils.c */
  EXTERN(long) jdiv_round_up JPP((long a, long b));
  EXTERN(long) jround_up JPP((long a, long b));
  EXTERN(void) jcopy_sample_rows JPP((JSAMPARRAY input_array, int source_row,
                                      JSAMPARRAY output_array, int dest_row,
                                      int num_rows, JDIMENSION num_cols));
  EXTERN(void) jcopy_block_row JPP((JBLOCKROW input_row, JBLOCKROW output_row,
                                    JDIMENSION num_blocks));
  EXTERN(void) jzero_far JPP((void FAR * target, size_t bytestozero));
  /* Constant tables in jutils.c */
  #if 0                           /* This table is not actually needed in v6a */
  extern const int jpeg_zigzag_order[]; /* natural coef order to zigzag order */
  #endif
  extern const int jpeg_natural_order[]; /* zigzag coef order to natural order */
  
  /* Arithmetic coding probability estimation tables in jaricom.c */
  extern const INT32 jpeg_aritab[];
  
  /* Suppress undefined-structure complaints if necessary. */
  
  #ifdef INCOMPLETE_TYPES_BROKEN
  #ifndef AM_MEMORY_MANAGER       /* only jmemmgr.c defines these */
  struct jvirt_sarray_control { long dummy; };
  struct jvirt_barray_control { long dummy; };
  #endif
  #endif /* INCOMPLETE_TYPES_BROKEN */
  