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/*
* MJPEG decoder
* Copyright (c) 2000, 2001 Fabrice Bellard
* Copyright (c) 2003 Alex Beregszaszi
* Copyright (c) 2003-2004 Michael Niedermayer
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* MJPEG decoder.
*/
#ifndef AVCODEC_MJPEGDEC_H
#define AVCODEC_MJPEGDEC_H
#include "avcodec.h"
#include "get_bits.h"
#include "dsputil.h"
#define MAX_COMPONENTS 4
typedef struct MJpegDecodeContext {
AVCodecContext *avctx;
GetBitContext gb;
int start_code; /* current start code */
int buffer_size;
uint8_t *buffer;
int16_t quant_matrixes[4][64];
VLC vlcs[3][4];
int qscale[4]; ///< quantizer scale calculated from quant_matrixes
int org_height; /* size given at codec init */
int first_picture; /* true if decoding first picture */
int interlaced; /* true if interlaced */
int bottom_field; /* true if bottom field */
int lossless;
int ls;
int progressive;
int rgb;
int rct; /* standard rct */
int pegasus_rct; /* pegasus reversible colorspace transform */
int bits; /* bits per component */
int maxval;
int near; ///< near lossless bound (si 0 for lossless)
int t1,t2,t3;
int reset; ///< context halfing intervall ?rename
int width, height;
int mb_width, mb_height;
int nb_components;
int block_stride[MAX_COMPONENTS];
int component_id[MAX_COMPONENTS];
int h_count[MAX_COMPONENTS]; /* horizontal and vertical count for each component */
int v_count[MAX_COMPONENTS];
int comp_index[MAX_COMPONENTS];
int dc_index[MAX_COMPONENTS];
int ac_index[MAX_COMPONENTS];
int nb_blocks[MAX_COMPONENTS];
int h_scount[MAX_COMPONENTS];
int v_scount[MAX_COMPONENTS];
int h_max, v_max; /* maximum h and v counts */
int quant_index[4]; /* quant table index for each component */
int last_dc[MAX_COMPONENTS]; /* last DEQUANTIZED dc (XXX: am I right to do that ?) */
AVFrame picture; /* picture structure */
AVFrame *picture_ptr; /* pointer to picture structure */
int got_picture; ///< we found a SOF and picture is valid, too.
int linesize[MAX_COMPONENTS]; ///< linesize << interlaced
int8_t *qscale_table;
DECLARE_ALIGNED(16, DCTELEM, block)[64];
DCTELEM (*blocks[MAX_COMPONENTS])[64]; ///< intermediate sums (progressive mode)
uint8_t *last_nnz[MAX_COMPONENTS];
uint64_t coefs_finished[MAX_COMPONENTS]; ///< bitmask of which coefs have been completely decoded (progressive mode)
ScanTable scantable;
DSPContext dsp;
int restart_interval;
int restart_count;
int buggy_avid;
int cs_itu601;
int interlace_polarity;
int mjpb_skiptosod;
int cur_scan; /* current scan, used by JPEG-LS */
int flipped; /* true if picture is flipped */
uint16_t (*ljpeg_buffer)[4];
unsigned int ljpeg_buffer_size;
} MJpegDecodeContext;
int ff_mjpeg_decode_init(AVCodecContext *avctx);
int ff_mjpeg_decode_end(AVCodecContext *avctx);
int ff_mjpeg_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
AVPacket *avpkt);
int ff_mjpeg_decode_dqt(MJpegDecodeContext *s);
int ff_mjpeg_decode_dht(MJpegDecodeContext *s);
int ff_mjpeg_decode_sof(MJpegDecodeContext *s);
int ff_mjpeg_decode_sos(MJpegDecodeContext *s,
const uint8_t *mb_bitmask, const AVFrame *reference);
int ff_mjpeg_find_marker(MJpegDecodeContext *s,
const uint8_t **buf_ptr, const uint8_t *buf_end,
const uint8_t **unescaped_buf_ptr, int *unescaped_buf_size);
#endif /* AVCODEC_MJPEGDEC_H */
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