FFmpeg: libavcodec/mpc.h Source File

FFmpeg

libavcodec

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 <stdint.h>

33

34 #include "libavutil/lfg.h"

35 #include "libavutil/mem_internal.h"

36

37 #include "bswapdsp.h"

38 #include "mpegaudio.h"

39 #include "mpegaudiodsp.h"

40

41 #define BANDS 32

42 #define SAMPLES_PER_BAND 36

43 #define MPC_FRAME_SIZE (BANDS * SAMPLES_PER_BAND)

44

45 /** Subband structure - hold all variables for each subband */

46 typedef struct Band {

47 int msf; ///< mid-stereo flag

48 int res[2];

49 int scfi[2];

50 int scf_idx[2][3];

51 int Q[2];

52 }Band;

53

54 typedef struct MPCContext {

55 BswapDSPContext bdsp;

56 MPADSPContext mpadsp;

57 int IS, MSS, gapless;

58 int lastframelen;

59 int maxbands, last_max_band;

60 int last_bits_used;

61 int oldDSCF[2][BANDS];

62 Band bands[BANDS];

63 int Q[2][MPC_FRAME_SIZE];

64 int cur_frame, frames;

65 uint8_t *bits;

66 int buf_size;

68 int frames_to_skip;

69 /* for synthesis */

70 DECLARE_ALIGNED(16, MPA_INT, synth_buf)[MPA_MAX_CHANNELS][512*2];

71 int synth_buf_offset[MPA_MAX_CHANNELS];

72 DECLARE_ALIGNED(16, int32_t, sb_samples)[MPA_MAX_CHANNELS][36][SBLIMIT];

73 } MPCContext;

74

75 void ff_mpc_dequantize_and_synth(MPCContext *c, int maxband, int16_t **out, int channels);

76

77 #endif /* AVCODEC_MPC_H */

FILE * out

Definition: movenc.c:55

MPCContext::frames_to_skip

int frames_to_skip

Definition: mpc.h:68

MPCContext::last_max_band

int last_max_band

Definition: mpc.h:59

int msf

mid-stereo flag

Definition: mpc.h:47

Definition: mpegaudiodsp.h:28

MPCContext::lastframelen

int lastframelen

Definition: mpc.h:58

MPCContext::sb_samples

int32_t sb_samples[MPA_MAX_CHANNELS][36][SBLIMIT]

Definition: mpc.h:72

Definition: mpc.h:54

MPCContext::gapless

int gapless

Definition: mpc.h:57

int res[2]

Definition: mpc.h:48

MPCContext::mpadsp

MPADSPContext mpadsp

Definition: mpc.h:56

MPCContext::rnd

AVLFG rnd

Definition: mpc.h:67

MPCContext::last_bits_used

int last_bits_used

Definition: mpc.h:60

MPCContext::synth_buf

MPA_INT synth_buf[MPA_MAX_CHANNELS][512 *2]

Definition: mpc.h:70

MPCContext::buf_size

int buf_size

Definition: mpc.h:66

MPCContext::cur_frame

int cur_frame

Definition: mpc.h:64

MPCContext::maxbands

int maxbands

Definition: mpc.h:59

int scf_idx[2][3]

Definition: mpc.h:50

MPCContext::bits

uint8_t * bits

Definition: mpc.h:65

channels

Definition: aptx.h:31

ff_mpc_dequantize_and_synth

void ff_mpc_dequantize_and_synth(MPCContext *c, int maxband, int16_t **out, int channels)

Definition: mpc.c:55

int IS

Definition: mpc.h:57

#define MPC_FRAME_SIZE

Definition: mpc.h:43

int scfi[2]

Definition: mpc.h:49

#define SBLIMIT

Definition: mpegaudio.h:44

c

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

#define BANDS

Definition: mpc.h:41

Context structure for the Lagged Fibonacci PRNG.

Definition: lfg.h:33

DECLARE_ALIGNED

#define DECLARE_ALIGNED(n, t, v)

Definition: mem_internal.h:104

MPCContext::oldDSCF

int oldDSCF[2][BANDS]

Definition: mpc.h:61

MPCContext::bands

Band bands[BANDS]

Definition: mpc.h:62

MPCContext::bdsp

BswapDSPContext bdsp

Definition: mpc.h:55

MPCContext::MSS

int MSS

Definition: mpc.h:57

MPCContext::synth_buf_offset

int synth_buf_offset[MPA_MAX_CHANNELS]

Definition: mpc.h:71

Subband structure - hold all variables for each subband.

Definition: mpc.h:46

int32_t MPA_INT

Definition: mpegaudio.h:75

int Q[2]

Definition: mpc.h:51

int32_t

Definition: audioconvert.c:56

MPA_MAX_CHANNELS

#define MPA_MAX_CHANNELS

Definition: mpegaudio.h:42

BswapDSPContext

Definition: bswapdsp.h:24

MPCContext::frames

int frames

Definition: mpc.h:64

int Q[2][MPC_FRAME_SIZE]

Definition: mpc.h:63

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