FFmpeg/libavcodec/mjpegdec.h
Nick Renieris 40abff05d2 lavc/mjpegdec: Decode Huffman-coded lossless JPEGs embedded in DNGs
Main image data in DNGs is usually comprised of tiles, each of which is a Huffman-encoded lossless JPEG.

Tested for ljpeg regressions with:
`ffmpeg -f lavfi -i testsrc=d=1 -vcodec ljpeg test.avi`
`ffmpeg test.avi out.avi`
The modified code in ljpeg_decode_rgb_scan runs without issues.

Signed-off-by: Nick Renieris <velocityra@gmail.com>
2019-09-02 09:26:52 +02:00

173 lines
5.6 KiB
C

/*
* MJPEG decoder
* Copyright (c) 2000, 2001 Fabrice Bellard
* Copyright (c) 2003 Alex Beregszaszi
* Copyright (c) 2003-2004 Michael Niedermayer
*
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; 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 "libavutil/log.h"
#include "libavutil/pixdesc.h"
#include "libavutil/stereo3d.h"
#include "avcodec.h"
#include "blockdsp.h"
#include "get_bits.h"
#include "hpeldsp.h"
#include "idctdsp.h"
#undef near /* This file uses struct member 'near' which in windows.h is defined as empty. */
#define MAX_COMPONENTS 4
typedef struct MJpegDecodeContext {
AVClass *class;
AVCodecContext *avctx;
GetBitContext gb;
int buf_size;
int start_code; /* current start code */
int buffer_size;
uint8_t *buffer;
uint16_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 bayer; /* true if it's a bayer-encoded JPEG embedded in a DNG */
int rgb;
uint8_t upscale_h[4];
uint8_t upscale_v[4];
int rct; /* standard rct */
int pegasus_rct; /* pegasus reversible colorspace transform */
int bits; /* bits per component */
int colr;
int xfrm;
int adobe_transform;
int maxval;
int near; ///< near lossless bound (si 0 for lossless)
int t1,t2,t3;
int reset; ///< context halfing interval ?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 quant_sindex[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(32, int16_t, block)[64];
int16_t (*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)
int palette_index;
ScanTable scantable;
BlockDSPContext bdsp;
HpelDSPContext hdsp;
IDCTDSPContext idsp;
int restart_interval;
int restart_count;
int buggy_avid;
int cs_itu601;
int interlace_polarity;
int multiscope;
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;
int extern_huff;
AVDictionary *exif_metadata;
AVStereo3D *stereo3d; ///!< stereoscopic information (cached, since it is read before frame allocation)
const AVPixFmtDescriptor *pix_desc;
uint8_t **iccdata;
int *iccdatalens;
int iccnum;
int iccread;
// Raw stream data for hwaccel use.
const uint8_t *raw_image_buffer;
size_t raw_image_buffer_size;
const uint8_t *raw_scan_buffer;
size_t raw_scan_buffer_size;
uint8_t raw_huffman_lengths[2][4][16];
uint8_t raw_huffman_values[2][4][256];
enum AVPixelFormat hwaccel_sw_pix_fmt;
enum AVPixelFormat hwaccel_pix_fmt;
void *hwaccel_picture_private;
} 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 *got_frame,
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,int mb_bitmask_size,
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 */