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mjpegdec.h
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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
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 
38 #define MAX_COMPONENTS 4
39 
40 typedef struct MJpegDecodeContext {
41  AVClass *class;
44 
45  int start_code; /* current start code */
48 
49  int16_t quant_matrixes[4][64];
50  VLC vlcs[3][4];
51  int qscale[4]; ///< quantizer scale calculated from quant_matrixes
52 
53  int org_height; /* size given at codec init */
54  int first_picture; /* true if decoding first picture */
55  int interlaced; /* true if interlaced */
56  int bottom_field; /* true if bottom field */
57  int lossless;
58  int ls;
60  int rgb;
61  int upscale_h;
63  int upscale_v;
64  int rct; /* standard rct */
65  int pegasus_rct; /* pegasus reversible colorspace transform */
66  int bits; /* bits per component */
67 
68  int maxval;
69  int near; ///< near lossless bound (si 0 for lossless)
70  int t1,t2,t3;
71  int reset; ///< context halfing interval ?rename
72 
73  int width, height;
78  int h_count[MAX_COMPONENTS]; /* horizontal and vertical count for each component */
86  int h_max, v_max; /* maximum h and v counts */
87  int quant_index[4]; /* quant table index for each component */
88  int last_dc[MAX_COMPONENTS]; /* last DEQUANTIZED dc (XXX: am I right to do that ?) */
89  AVFrame picture; /* picture structure */
90  AVFrame *picture_ptr; /* pointer to picture structure */
91  int got_picture; ///< we found a SOF and picture is valid, too.
92  int linesize[MAX_COMPONENTS]; ///< linesize << interlaced
93  int8_t *qscale_table;
95  DCTELEM (*blocks[MAX_COMPONENTS])[64]; ///< intermediate sums (progressive mode)
97  uint64_t coefs_finished[MAX_COMPONENTS]; ///< bitmask of which coefs have been completely decoded (progressive mode)
100 
103 
107 
109 
110  int cur_scan; /* current scan, used by JPEG-LS */
111  int flipped; /* true if picture is flipped */
112 
113  uint16_t (*ljpeg_buffer)[4];
114  unsigned int ljpeg_buffer_size;
115 
118 
122  void *data, int *got_frame,
123  AVPacket *avpkt);
128  const uint8_t *mb_bitmask, const AVFrame *reference);
130  const uint8_t **buf_ptr, const uint8_t *buf_end,
131  const uint8_t **unescaped_buf_ptr, int *unescaped_buf_size);
132 
133 #endif /* AVCODEC_MJPEGDEC_H */