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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* JPEG image viewer
* (This is a real mess if it has to be coded in one single C file)
*
* File scrolling addition (C) 2005 Alexander Spyridakis
* Copyright (C) 2004 Jörg Hohensohn aka [IDC]Dragon
* Heavily borrowed from the IJG implementation (C) Thomas G. Lane
* Small & fast downscaling IDCT (C) 2002 by Guido Vollbeding JPEGclub.org
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef _JPEG_JPEG_DECODER_H
#define _JPEG_JPEG_DECODER_H
#include "jpeg_common.h"
struct jpeg
{
int x_size, y_size; /* size of image (can be less than block boundary) */
int x_phys, y_phys; /* physical size, block aligned */
int x_mbl; /* x dimension of MBL */
int y_mbl; /* y dimension of MBL */
int blocks; /* blocks per MB */
int restart_interval; /* number of MCUs between RSTm markers */
int store_pos[4]; /* for Y block ordering */
unsigned char* p_entropy_data;
unsigned char* p_entropy_end;
int quanttable[4][QUANT_TABLE_LENGTH]; /* raw quantization tables 0-3 */
int qt_idct[2][QUANT_TABLE_LENGTH]; /* quantization tables for IDCT */
struct huffman_table hufftable[2]; /* Huffman tables */
struct derived_tbl dc_derived_tbls[2]; /* Huffman-LUTs */
struct derived_tbl ac_derived_tbls[2];
struct frame_component frameheader[3]; /* Component descriptor */
struct scan_component scanheader[3]; /* currently not used */
int mcu_membership[6]; /* info per block */
int tab_membership[6];
int subsample_x[3]; /* info per component */
int subsample_y[3];
};
/* various helper functions */
void default_huff_tbl(struct jpeg* p_jpeg);
void build_lut(struct jpeg* p_jpeg);
int process_markers(unsigned char* p_src, long size, struct jpeg* p_jpeg);
/* the main decode function */
#ifdef HAVE_LCD_COLOR
int jpeg_decode(struct jpeg* p_jpeg, unsigned char* p_pixel[3],
int downscale, void (*pf_progress)(int current, int total));
#else
int jpeg_decode(struct jpeg* p_jpeg, unsigned char* p_pixel[1], int downscale,
void (*pf_progress)(int current, int total));
#endif
#endif /* _JPEG_JPEG_DECODER_H */
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