jpegint.h

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          http://www.mrpt.org/                          |
   |                                                                        |
   | Copyright (c) 2005-2017, Individual contributors, see AUTHORS file     |
   | See: http://www.mrpt.org/Authors - All rights reserved.                |
   | Released under BSD License. See details in http://www.mrpt.org/License |
   +------------------------------------------------------------------------+ */

/* 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 nullptr 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_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_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
#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_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_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 */

/* 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 */