1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
|
/*
* 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 "libavutil/log.h"
#include "avcodec.h"
#include "get_bits.h"
#include "dsputil.h"
#define MAX_COMPONENTS 4
typedef struct MJpegDecodeContext {
AVClass *class;
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;
int extern_huff;
} 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 */
|
