FFmpeg
mpeg12dec.h
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1 /*
2  * MPEG-1/2 decoder header
3  * Copyright (c) 2007 Aurelien Jacobs <aurel@gnuage.org>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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_MPEG12DEC_H
23 #define AVCODEC_MPEG12DEC_H
24 
25 #include "get_bits.h"
26 #include "mpeg12vlc.h"
27 
28 static inline int decode_dc(GetBitContext *gb, int component)
29 {
30  int code, diff;
31 
32  if (component == 0) {
34  } else {
36  }
37  if (code == 0) {
38  diff = 0;
39  } else {
40  diff = get_xbits(gb, code);
41  }
42  return diff;
43 }
44 
46  const uint16_t *quant_matrix,
47  const uint8_t *scantable, int last_dc[3],
48  int16_t *block, int index, int qscale);
49 
50 #endif /* AVCODEC_MPEG12DEC_H */
ff_dc_chroma_vlc
VLC ff_dc_chroma_vlc
Definition: mpeg12.c:121
GetBitContext
Definition: get_bits.h:61
mpeg12vlc.h
get_bits.h
get_vlc2
static av_always_inline int get_vlc2(GetBitContext *s, const VLCElem *table, int bits, int max_depth)
Parse a vlc code.
Definition: get_bits.h:787
index
int index
Definition: gxfenc.c:89
get_xbits
static int get_xbits(GetBitContext *s, int n)
Read MPEG-1 dc-style VLC (sign bit + mantissa with no MSB).
Definition: get_bits.h:321
code
and forward the test the status of outputs and forward it to the corresponding return FFERROR_NOT_READY If the filters stores internally one or a few frame for some it can consider them to be part of the FIFO and delay acknowledging a status change accordingly Example code
Definition: filter_design.txt:178
ff_dc_lum_vlc
VLC ff_dc_lum_vlc
Definition: mpeg12.c:120
VLC::table
VLCElem * table
Definition: vlc.h:33
diff
static av_always_inline int diff(const uint32_t a, const uint32_t b)
Definition: vf_palettegen.c:139
ff_mpeg1_decode_block_intra
int ff_mpeg1_decode_block_intra(GetBitContext *gb, const uint16_t *quant_matrix, const uint8_t *scantable, int last_dc[3], int16_t *block, int index, int qscale)
Definition: mpeg12.c:238
block
The exact code depends on how similar the blocks are and how related they are to the block
Definition: filter_design.txt:207
DC_VLC_BITS
#define DC_VLC_BITS
Definition: intrax8.c:40
decode_dc
static int decode_dc(GetBitContext *gb, int component)
Definition: mpeg12dec.h:28