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/*
* Small jpeg decoder library (Internal header)
*
* Copyright (c) 2006, Luc Saillard <luc@saillard.org>
* All rights reserved.
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* - Neither the name of the author nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
*/
#ifndef __TINYJPEG_INTERNAL_H_
#define __TINYJPEG_INTERNAL_H_
#include <setjmp.h>
#define SANITY_CHECK 1
struct jdec_private;
#define HUFFMAN_HASH_NBITS 9
#define HUFFMAN_HASH_SIZE (1UL<<HUFFMAN_HASH_NBITS)
#define HUFFMAN_HASH_MASK (HUFFMAN_HASH_SIZE-1)
#define HUFFMAN_TABLES 4
#define COMPONENTS 3
#define JPEG_MAX_WIDTH 2048
#define JPEG_MAX_HEIGHT 2048
struct huffman_table {
/* Fast look up table, using HUFFMAN_HASH_NBITS bits we can have directly the symbol,
* if the symbol is <0, then we need to look into the tree table */
short int lookup[HUFFMAN_HASH_SIZE];
/* code size: give the number of bits of a symbol is encoded */
unsigned char code_size[HUFFMAN_HASH_SIZE];
/* some place to store value that is not encoded in the lookup table
* IMPROVEME: Calculate if 256 value is enough to store all values
*/
uint16_t slowtable[16 - HUFFMAN_HASH_NBITS][256];
};
struct component {
unsigned int Hfactor;
unsigned int Vfactor;
float *Q_table; /* Pointer to the quantisation table to use */
struct huffman_table *AC_table;
struct huffman_table *DC_table;
short int previous_DC; /* Previous DC coefficient */
short int DCT[64]; /* DCT coef */
#if SANITY_CHECK
unsigned int cid;
#endif
};
typedef void (*decode_MCU_fct) (struct jdec_private *priv);
typedef void (*convert_colorspace_fct) (struct jdec_private *priv);
struct jdec_private {
/* Public variables */
uint8_t *components[COMPONENTS];
unsigned int width, height; /* Size of the image */
unsigned int flags;
/* Private variables */
const unsigned char *stream_end;
const unsigned char *stream; /* Pointer to the current stream */
unsigned char *stream_filtered;
int stream_filtered_bufsize;
unsigned int reservoir, nbits_in_reservoir;
struct component component_infos[COMPONENTS];
float Q_tables[COMPONENTS][64]; /* quantization tables */
struct huffman_table HTDC[HUFFMAN_TABLES]; /* DC huffman tables */
struct huffman_table HTAC[HUFFMAN_TABLES]; /* AC huffman tables */
int default_huffman_table_initialized;
int restart_interval;
int restarts_to_go; /* MCUs left in this restart interval */
int last_rst_marker_seen; /* Rst marker is incremented each time */
#if SANITY_CHECK
unsigned int current_cid; /* For planar JPEG */
#endif
unsigned char marker; /* for PJPG (Pixart JPEG) */
unsigned char first_marker; /* for PJPG (Pixart JPEG) */
/* Temp space used after the IDCT to store each components */
uint8_t Y[64 * 4], Cr[64], Cb[64];
jmp_buf jump_state;
/* Internal Pointer use for colorspace conversion, do not modify it !!! */
uint8_t *plane[COMPONENTS];
char error_string[256];
/* Temp buffers for multipass planar JPG -> RGB decoding */
int tmp_buf_y_size;
uint8_t *tmp_buf[COMPONENTS];
};
#define IDCT tinyjpeg_idct_float
void tinyjpeg_idct_float (struct component *compptr, uint8_t *output_buf, int stride);
#endif
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