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
|
/*
* MPEG1/2 common code
* Copyright (c) 2007 Aurelien Jacobs <aurel@gnuage.org>
*
* 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
*/
#ifndef AVCODEC_MPEG12_H
#define AVCODEC_MPEG12_H
#include "mpegvideo.h"
#define DC_VLC_BITS 9
#define TEX_VLC_BITS 9
extern VLC ff_dc_lum_vlc;
extern VLC ff_dc_chroma_vlc;
typedef struct Mpeg1Context {
MpegEncContext mpeg_enc_ctx;
int mpeg_enc_ctx_allocated; /* true if decoding context allocated */
int repeat_field; /* true if we must repeat the field */
AVPanScan pan_scan; /**< some temporary storage for the panscan */
int slice_count;
int swap_uv;//indicate VCR2
int save_aspect_info;
int save_width, save_height, save_progressive_seq;
AVRational frame_rate_ext; ///< MPEG-2 specific framerate modificator
int sync; ///< Did we reach a sync point like a GOP/SEQ/KEYFrame?
int closed_gop; ///< GOP is closed
} Mpeg1Context;
extern uint8_t ff_mpeg12_static_rl_table_store[2][2][2*MAX_RUN + MAX_LEVEL + 3];
void ff_mpeg12_common_init(MpegEncContext *s);
void ff_mpeg12_init_vlcs(void);
static inline int decode_dc(GetBitContext *gb, int component)
{
int code, diff;
if (component == 0) {
code = get_vlc2(gb, ff_dc_lum_vlc.table, DC_VLC_BITS, 2);
} else {
code = get_vlc2(gb, ff_dc_chroma_vlc.table, DC_VLC_BITS, 2);
}
if (code < 0){
av_log(NULL, AV_LOG_ERROR, "invalid dc code at\n");
return 0xffff;
}
if (code == 0) {
diff = 0;
} else {
diff = get_xbits(gb, code);
}
return diff;
}
extern int ff_mpeg1_decode_block_intra(MpegEncContext *s, DCTELEM *block, int n);
#endif /* AVCODEC_MPEG12_H */
|
