Libav
mpeg12.h
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1 /*
2  * MPEG1/2 common code
3  * Copyright (c) 2007 Aurelien Jacobs <aurel@gnuage.org>
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #ifndef AVCODEC_MPEG12_H
23 #define AVCODEC_MPEG12_H
24 
25 #include "mpegvideo.h"
26 
27 #define DC_VLC_BITS 9
28 #define MV_VLC_BITS 9
29 #define TEX_VLC_BITS 9
30 
31 #define MBINCR_VLC_BITS 9
32 #define MB_PAT_VLC_BITS 9
33 #define MB_PTYPE_VLC_BITS 6
34 #define MB_BTYPE_VLC_BITS 6
35 
36 extern VLC ff_dc_lum_vlc;
37 extern VLC ff_dc_chroma_vlc;
38 extern VLC ff_mbincr_vlc;
39 extern VLC ff_mb_ptype_vlc;
40 extern VLC ff_mb_btype_vlc;
41 extern VLC ff_mb_pat_vlc;
42 extern VLC ff_mv_vlc;
43 
45 
47 void ff_mpeg12_init_vlcs(void);
48 
49 static inline int decode_dc(GetBitContext *gb, int component)
50 {
51  int code, diff;
52 
53  if (component == 0) {
54  code = get_vlc2(gb, ff_dc_lum_vlc.table, DC_VLC_BITS, 2);
55  } else {
56  code = get_vlc2(gb, ff_dc_chroma_vlc.table, DC_VLC_BITS, 2);
57  }
58  if (code < 0){
59  av_log(NULL, AV_LOG_ERROR, "invalid dc code at\n");
60  return 0xffff;
61  }
62  if (code == 0) {
63  diff = 0;
64  } else {
65  diff = get_xbits(gb, code);
66  }
67  return diff;
68 }
69 
70 int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n);
72 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s);
73 
74 #endif /* AVCODEC_MPEG12_H */
#define DC_VLC_BITS
Definition: mpeg12.h:27
mpegvideo header.
VLC ff_mb_btype_vlc
Definition: mpeg12.c:136
uint8_t ff_mpeg12_static_rl_table_store[2][2][2 *MAX_RUN+MAX_LEVEL+3]
Definition: mpeg12.c:39
uint8_t
void ff_mpeg12_common_init(MpegEncContext *s)
Definition: mpeg12.c:109
VLC ff_mb_ptype_vlc
Definition: mpeg12.c:135
#define MAX_LEVEL
Definition: rl.h:35
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:148
static int decode_dc(GetBitContext *gb, int component)
Definition: mpeg12.h:49
Definition: get_bits.h:64
static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE(*table)[2], int bits, int max_depth)
Parse a vlc code.
Definition: get_bits.h:522
VLC ff_mbincr_vlc
Definition: mpeg12.c:134
NULL
Definition: eval.c:55
VLC ff_dc_lum_vlc
Definition: mpeg12.c:131
static int get_xbits(GetBitContext *s, int n)
read mpeg1 dc style vlc (sign bit + mantisse with no MSB).
Definition: get_bits.h:213
void ff_mpeg1_clean_buffers(MpegEncContext *s)
Definition: mpeg12.c:117
int ff_mpeg1_decode_block_intra(MpegEncContext *s, int16_t *block, int n)
Definition: mpeg12dec.c:208
MpegEncContext.
Definition: mpegvideo.h:264
#define MAX_RUN
Definition: rl.h:34
void ff_mpeg12_init_vlcs(void)
Definition: mpeg12.c:139
VLC ff_mb_pat_vlc
Definition: mpeg12.c:137
VLC ff_dc_chroma_vlc
Definition: mpeg12.c:132
VLC_TYPE(* table)[2]
code, bits
Definition: get_bits.h:66
VLC ff_mv_vlc
Definition: mpeg12.c:129
int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s)
Find the end of the current frame in the bitstream.
Definition: mpeg12.c:180
static int16_t block[64]
Definition: dct-test.c:170