FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
mjpegdec.h
Go to the documentation of this file.
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
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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  */
23 
24 /**
25  * @file
26  * MJPEG decoder.
27  */
28 
29 #ifndef AVCODEC_MJPEGDEC_H
30 #define AVCODEC_MJPEGDEC_H
31 
32 #include "libavutil/log.h"
33 
34 #include "avcodec.h"
35 #include "get_bits.h"
36 #include "dsputil.h"
37 #include "hpeldsp.h"
38 
39 #define MAX_COMPONENTS 4
40 
41 typedef struct MJpegDecodeContext {
42  AVClass *class;
45 
46  int start_code; /* current start code */
49 
50  int16_t quant_matrixes[4][64];
51  VLC vlcs[3][4];
52  int qscale[4]; ///< quantizer scale calculated from quant_matrixes
53 
54  int org_height; /* size given at codec init */
55  int first_picture; /* true if decoding first picture */
56  int interlaced; /* true if interlaced */
57  int bottom_field; /* true if bottom field */
58  int lossless;
59  int ls;
61  int rgb;
62  int upscale_h;
64  int upscale_v;
65  int rct; /* standard rct */
66  int pegasus_rct; /* pegasus reversible colorspace transform */
67  int bits; /* bits per component */
68  int colr;
69  int xfrm;
70 
71  int maxval;
72  int near; ///< near lossless bound (si 0 for lossless)
73  int t1,t2,t3;
74  int reset; ///< context halfing interval ?rename
75 
76  int width, height;
81  int h_count[MAX_COMPONENTS]; /* horizontal and vertical count for each component */
90  int h_max, v_max; /* maximum h and v counts */
91  int quant_index[4]; /* quant table index for each component */
92  int last_dc[MAX_COMPONENTS]; /* last DEQUANTIZED dc (XXX: am I right to do that ?) */
93  AVFrame *picture; /* picture structure */
94  AVFrame *picture_ptr; /* pointer to picture structure */
95  int got_picture; ///< we found a SOF and picture is valid, too.
96  int linesize[MAX_COMPONENTS]; ///< linesize << interlaced
97  int8_t *qscale_table;
98  DECLARE_ALIGNED(16, int16_t, block)[64];
99  int16_t (*blocks[MAX_COMPONENTS])[64]; ///< intermediate sums (progressive mode)
101  uint64_t coefs_finished[MAX_COMPONENTS]; ///< bitmask of which coefs have been completely decoded (progressive mode)
105 
108 
112 
114 
115  int cur_scan; /* current scan, used by JPEG-LS */
116  int flipped; /* true if picture is flipped */
117 
118  uint16_t (*ljpeg_buffer)[4];
119  unsigned int ljpeg_buffer_size;
120 
124 
128  void *data, int *got_frame,
129  AVPacket *avpkt);
134  const uint8_t *mb_bitmask, const AVFrame *reference);
136  const uint8_t **buf_ptr, const uint8_t *buf_end,
137  const uint8_t **unescaped_buf_ptr, int *unescaped_buf_size);
138 
139 #endif /* AVCODEC_MJPEGDEC_H */