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1 /*
2  * MJPEG decoder
3  * Copyright (c) 2000, 2001 Fabrice Bellard
4  * Copyright (c) 2003 Alex Beregszaszi
5  * Copyright (c) 2003-2004 Michael Niedermayer
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
24 /**
25  * @file
26  * MJPEG decoder.
27  */
32 #include "libavutil/log.h"
33 #include "libavutil/pixdesc.h"
34 #include "libavutil/stereo3d.h"
36 #include "avcodec.h"
37 #include "blockdsp.h"
38 #include "get_bits.h"
39 #include "hpeldsp.h"
40 #include "idctdsp.h"
42 #define MAX_COMPONENTS 4
44 typedef struct MJpegDecodeContext {
45  AVClass *class;
49  int start_code; /* current start code */
53  int16_t quant_matrixes[4][64];
54  VLC vlcs[3][4];
55  int qscale[4]; ///< quantizer scale calculated from quant_matrixes
57  int org_height; /* size given at codec init */
58  int first_picture; /* true if decoding first picture */
59  int interlaced; /* true if interlaced */
60  int bottom_field; /* true if bottom field */
61  int lossless;
62  int ls;
64  int rgb;
67  int rct; /* standard rct */
68  int pegasus_rct; /* pegasus reversible colorspace transform */
69  int bits; /* bits per component */
70  int colr;
71  int xfrm;
74  int maxval;
75  int near; ///< near lossless bound (si 0 for lossless)
76  int t1,t2,t3;
77  int reset; ///< context halfing interval ?rename
79  int width, height;
84  int h_count[MAX_COMPONENTS]; /* horizontal and vertical count for each component */
93  int h_max, v_max; /* maximum h and v counts */
94  int quant_index[4]; /* quant table index for each component */
95  int last_dc[MAX_COMPONENTS]; /* last DEQUANTIZED dc (XXX: am I right to do that ?) */
96  AVFrame *picture; /* picture structure */
97  AVFrame *picture_ptr; /* pointer to picture structure */
98  int got_picture; ///< we found a SOF and picture is valid, too.
99  int linesize[MAX_COMPONENTS]; ///< linesize << interlaced
100  int8_t *qscale_table;
101  DECLARE_ALIGNED(16, int16_t, block)[64];
102  int16_t (*blocks[MAX_COMPONENTS])[64]; ///< intermediate sums (progressive mode)
104  uint64_t coefs_finished[MAX_COMPONENTS]; ///< bitmask of which coefs have been completely decoded (progressive mode)
121  int cur_scan; /* current scan, used by JPEG-LS */
122  int flipped; /* true if picture is flipped */
124  uint16_t (*ljpeg_buffer)[4];
125  unsigned int ljpeg_buffer_size;
130  AVStereo3D *stereo3d; ///!< stereoscopic information (cached, since it is read before frame allocation)
138  void *data, int *got_frame,
139  AVPacket *avpkt);
144  const uint8_t *mb_bitmask,int mb_bitmask_size,
145  const AVFrame *reference);
147  const uint8_t **buf_ptr, const uint8_t *buf_end,
148  const uint8_t **unescaped_buf_ptr, int *unescaped_buf_size);
150 #endif /* AVCODEC_MJPEGDEC_H */
int block_stride[MAX_COMPONENTS]
Definition: mjpegdec.h:82
int ff_mjpeg_decode_sos(MJpegDecodeContext *s, const uint8_t *mb_bitmask, int mb_bitmask_size, const AVFrame *reference)
Definition: mjpegdec.c:1455
const AVPixFmtDescriptor * pix_desc
!< stereoscopic information (cached, since it is read before frame allocation)
Definition: mjpegdec.h:132
const char * s
Definition: avisynth_c.h:631
int v_count[MAX_COMPONENTS]
Definition: mjpegdec.h:85
This structure describes decoded (raw) audio or video data.
Definition: frame.h:184
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
int h_scount[MAX_COMPONENTS]
Definition: mjpegdec.h:90
BlockDSPContext bdsp
Definition: mjpegdec.h:107
Definition: idctdsp.h:29
int qscale[4]
quantizer scale calculated from quant_matrixes
Definition: mjpegdec.h:55
#define DECLARE_ALIGNED(n, t, v)
Definition: mem.h:53
uint8_t * buffer
Definition: mjpegdec.h:51
int dc_index[MAX_COMPONENTS]
Definition: mjpegdec.h:87
int linesize[MAX_COMPONENTS]
linesize << interlaced
Definition: mjpegdec.h:99
uint8_t upscale_v[4]
Definition: mjpegdec.h:66
int ff_mjpeg_decode_init(AVCodecContext *avctx)
Definition: mjpegdec.c:110
int comp_index[MAX_COMPONENTS]
Definition: mjpegdec.h:86
HpelDSPContext hdsp
Definition: mjpegdec.h:108
int16_t block[64]
Definition: mjpegdec.h:101
Stereo 3D type: this structure describes how two videos are packed within a single video surface...
Definition: stereo3d.h:123
uint16_t(* ljpeg_buffer)[4]
Definition: mjpegdec.h:124
unsigned int ljpeg_buffer_size
Definition: mjpegdec.h:125
int16_t quant_matrixes[4][64]
Definition: mjpegdec.h:53
uint8_t * last_nnz[MAX_COMPONENTS]
Definition: mjpegdec.h:103
AVFrame * picture_ptr
Definition: mjpegdec.h:97
int quant_sindex[MAX_COMPONENTS]
Definition: mjpegdec.h:92
Definition: mjpegdec.h:42
int h_count[MAX_COMPONENTS]
Definition: mjpegdec.h:84
bitstream reader API header.
int ff_mjpeg_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: mjpegdec.c:2060
int ff_mjpeg_decode_dqt(MJpegDecodeContext *s)
Definition: mjpegdec.c:167
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)
Definition: mjpegdec.c:1940
AVDictionary * exif_metadata
Definition: mjpegdec.h:128
int nb_blocks[MAX_COMPONENTS]
Definition: mjpegdec.h:89
VLC vlcs[3][4]
Definition: mjpegdec.h:54
int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
Definition: mjpegdec.c:263
Definition: vlc.h:26
ScanTable scantable
Definition: mjpegdec.h:106
Half-pel DSP context.
Definition: hpeldsp.h:45
int near
near lossless bound (si 0 for lossless)
Definition: mjpegdec.h:75
int component_id[MAX_COMPONENTS]
Definition: mjpegdec.h:83
int quant_index[4]
Definition: mjpegdec.h:94
int v_scount[MAX_COMPONENTS]
Definition: mjpegdec.h:91
GetBitContext gb
Definition: mjpegdec.h:47
int ff_mjpeg_decode_dht(MJpegDecodeContext *s)
Definition: mjpegdec.c:204
IDCTDSPContext idsp
Definition: mjpegdec.h:109
Half-pel DSP functions.
Libavcodec external API header.
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:81
AVStereo3D * stereo3d
Definition: mjpegdec.h:130
main external API structure.
Definition: avcodec.h:1649
int8_t * qscale_table
Definition: mjpegdec.h:100
Describe the class of an AVClass context structure.
Definition: log.h:67
int ac_index[MAX_COMPONENTS]
Definition: mjpegdec.h:88
int reset
context halfing interval ?rename
Definition: mjpegdec.h:77
uint64_t coefs_finished[MAX_COMPONENTS]
bitmask of which coefs have been completely decoded (progressive mode)
Definition: mjpegdec.h:104
AVCodecContext * avctx
Definition: mjpegdec.h:46
int got_picture
we found a SOF and picture is valid, too.
Definition: mjpegdec.h:98
int16_t(*[MAX_COMPONENTS] blocks)[64]
intermediate sums (progressive mode)
Definition: mjpegdec.h:102
AVFrame * picture
Definition: mjpegdec.h:96
int last_dc[MAX_COMPONENTS]
Definition: mjpegdec.h:95
uint8_t upscale_h[4]
Definition: mjpegdec.h:65
int ff_mjpeg_decode_end(AVCodecContext *avctx)
Definition: mjpegdec.c:2476
This structure stores compressed data.
Definition: avcodec.h:1557