FFmpeg
mpc.h
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1 /*
2  * Musepack decoder
3  * Copyright (c) 2006 Konstantin Shishkov
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 /**
23  * @file
24  * Musepack decoder
25  * MPEG Audio Layer 1/2 -like codec with frames of 1152 samples
26  * divided into 32 subbands.
27  */
28 
29 #ifndef AVCODEC_MPC_H
30 #define AVCODEC_MPC_H
31 
32 #include "libavutil/lfg.h"
33 
34 #include "avcodec.h"
35 #include "bswapdsp.h"
36 #include "mpegaudio.h"
37 #include "mpegaudiodsp.h"
38 
39 #define BANDS 32
40 #define SAMPLES_PER_BAND 36
41 #define MPC_FRAME_SIZE (BANDS * SAMPLES_PER_BAND)
42 
43 /** Subband structure - hold all variables for each subband */
44 typedef struct Band {
45  int msf; ///< mid-stereo flag
46  int res[2];
47  int scfi[2];
48  int scf_idx[2][3];
49  int Q[2];
50 }Band;
51 
52 typedef struct MPCContext {
55  int IS, MSS, gapless;
57  int maxbands, last_max_band;
59  int oldDSCF[2][BANDS];
61  int Q[2][MPC_FRAME_SIZE];
62  int cur_frame, frames;
64  int buf_size;
67  /* for synthesis */
68  DECLARE_ALIGNED(16, MPA_INT, synth_buf)[MPA_MAX_CHANNELS][512*2];
69  int synth_buf_offset[MPA_MAX_CHANNELS];
71 } MPCContext;
72 
73 void ff_mpc_init(void);
74 void ff_mpc_dequantize_and_synth(MPCContext *c, int maxband, int16_t **out, int channels);
75 
76 #endif /* AVCODEC_MPC_H */
Definition: lfg.h:27
int Q[2]
Definition: mpc.h:49
#define SBLIMIT
Definition: mpegaudio.h:44
MPADSPContext mpadsp
Definition: mpc.h:54
int msf
mid-stereo flag
Definition: mpc.h:45
channels
Definition: aptx.c:30
int res[2]
Definition: mpc.h:46
AVLFG rnd
Definition: mpc.h:65
int buf_size
Definition: mpc.h:64
int32_t MPA_INT
Definition: mpegaudio.h:75
int lastframelen
Definition: mpc.h:56
uint8_t
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
int scf_idx[2][3]
Definition: mpc.h:48
#define DECLARE_ALIGNED(n, t, v)
Declare a variable that is aligned in memory.
Definition: mem.h:112
void ff_mpc_init(void)
Definition: mpc.c:37
int last_bits_used
Definition: mpc.h:58
int maxbands
Definition: mpc.h:57
#define MPA_MAX_CHANNELS
Definition: mpegaudio.h:42
uint8_t * bits
Definition: mpc.h:63
#define MPC_FRAME_SIZE
Definition: mpc.h:41
void ff_mpc_dequantize_and_synth(MPCContext *c, int maxband, int16_t **out, int channels)
Definition: mpc.c:61
#define BANDS
Definition: mpc.h:39
int32_t
BswapDSPContext bdsp
Definition: mpc.h:53
Libavcodec external API header.
int scfi[2]
Definition: mpc.h:47
static const float bands[]
mpeg audio declarations for both encoder and decoder.
int MSS
Definition: mpc.h:55
int frames
Definition: mpc.h:62
FILE * out
Definition: movenc.c:54
Subband structure - hold all variables for each subband.
Definition: mpc.h:44
Definition: mpc.h:52
int frames_to_skip
Definition: mpc.h:66