FFmpeg
mpegaudiodec_float.c
Go to the documentation of this file.
1 /*
2  * Float MPEG Audio decoder
3  * Copyright (c) 2010 Michael Niedermayer
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 #include "config.h"
23 #include "config_components.h"
24 #include "libavutil/samplefmt.h"
25 
26 #define USE_FLOATS 1
27 
28 #include "codec_internal.h"
29 #include "mpegaudio.h"
30 
31 #define SHR(a,b) ((a)*(1.0f/(1<<(b))))
32 #define FIXR_OLD(a) ((int)((a) * FRAC_ONE + 0.5))
33 #define FIXR(x) ((float)(x))
34 #define FIXHR(x) ((float)(x))
35 #define MULH3(x, y, s) ((s)*(y)*(x))
36 #define MULLx(x, y, s) ((y)*(x))
37 #define RENAME(a) a ## _float
38 #define OUT_FMT AV_SAMPLE_FMT_FLT
39 #define OUT_FMT_P AV_SAMPLE_FMT_FLTP
40 
41 /* Intensity stereo table. See commit b91d46614df189e7905538e7f5c4ed9c7ed0d274
42  * (float based mp1/mp2/mp3 decoders.) for how they were created. */
43 static const float is_table[2][16] = {
44  { 0.000000000000000000e+00, 2.113248705863952637e-01, 3.660253882408142090e-01,
45  5.000000000000000000e-01, 6.339746117591857910e-01, 7.886751294136047363e-01,
46  1.000000000000000000e+00 },
47  { 1.000000000000000000e+00, 7.886751294136047363e-01, 6.339746117591857910e-01,
48  5.000000000000000000e-01, 3.660253882408142090e-01, 2.113248705863952637e-01,
49  0.000000000000000000e+00 }
50 };
51 
52 /* Antialiasing table. See commit 6f1ec38ce2193d3d4cacd87edb452c6d7ba751ec
53  * (mpegaudio: clean up compute_antialias() definition) for how they were
54  * created. */
55 static const float csa_table[8][4] = {
56  { 8.574929237365722656e-01, -5.144957900047302246e-01,
57  3.429971337318420410e-01, -1.371988654136657715e+00 },
58  { 8.817420005798339844e-01, -4.717319905757904053e-01,
59  4.100100100040435791e-01, -1.353474020957946777e+00 },
60  { 9.496286511421203613e-01, -3.133774697780609131e-01,
61  6.362511515617370605e-01, -1.263006091117858887e+00 },
62  { 9.833145737648010254e-01, -1.819131970405578613e-01,
63  8.014013767242431641e-01, -1.165227770805358887e+00 },
64  { 9.955177903175354004e-01, -9.457419067621231079e-02,
65  9.009436368942260742e-01, -1.090092062950134277e+00 },
66  { 9.991605877876281738e-01, -4.096558317542076111e-02,
67  9.581949710845947266e-01, -1.040126085281372070e+00 },
68  { 9.998992085456848145e-01, -1.419856864959001541e-02,
69  9.857006072998046875e-01, -1.014097809791564941e+00 },
70  { 9.999931454658508301e-01, -3.699974622577428818e-03,
71  9.962931871414184570e-01, -1.003693103790283203e+00 }
72 };
73 
74 #include "mpegaudiodec_template.c"
75 
76 #if CONFIG_MP1FLOAT_DECODER
78  .p.name = "mp1float",
79  CODEC_LONG_NAME("MP1 (MPEG audio layer 1)"),
80  .p.type = AVMEDIA_TYPE_AUDIO,
81  .p.id = AV_CODEC_ID_MP1,
82  .priv_data_size = sizeof(MPADecodeContext),
83  .init = decode_init,
85  .p.capabilities = AV_CODEC_CAP_CHANNEL_CONF |
87  .flush = flush,
88  .p.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
91 };
92 #endif
93 #if CONFIG_MP2FLOAT_DECODER
95  .p.name = "mp2float",
96  CODEC_LONG_NAME("MP2 (MPEG audio layer 2)"),
97  .p.type = AVMEDIA_TYPE_AUDIO,
98  .p.id = AV_CODEC_ID_MP2,
99  .priv_data_size = sizeof(MPADecodeContext),
100  .init = decode_init,
102  .p.capabilities = AV_CODEC_CAP_CHANNEL_CONF |
104  .flush = flush,
105  .p.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
108 };
109 #endif
110 #if CONFIG_MP3FLOAT_DECODER
112  .p.name = "mp3float",
113  CODEC_LONG_NAME("MP3 (MPEG audio layer 3)"),
114  .p.type = AVMEDIA_TYPE_AUDIO,
115  .p.id = AV_CODEC_ID_MP3,
116  .priv_data_size = sizeof(MPADecodeContext),
117  .init = decode_init,
119  .p.capabilities = AV_CODEC_CAP_CHANNEL_CONF |
121  .flush = flush,
122  .p.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
125 };
126 #endif
127 #if CONFIG_MP3ADUFLOAT_DECODER
129  .p.name = "mp3adufloat",
130  CODEC_LONG_NAME("ADU (Application Data Unit) MP3 (MPEG audio layer 3)"),
131  .p.type = AVMEDIA_TYPE_AUDIO,
132  .p.id = AV_CODEC_ID_MP3ADU,
133  .priv_data_size = sizeof(MPADecodeContext),
134  .init = decode_init,
135  FF_CODEC_DECODE_CB(decode_frame_adu),
136  .p.capabilities = AV_CODEC_CAP_CHANNEL_CONF |
138  .flush = flush,
139  .p.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
142 };
143 #endif
144 #if CONFIG_MP3ON4FLOAT_DECODER
146  .p.name = "mp3on4float",
147  CODEC_LONG_NAME("MP3onMP4"),
148  .p.type = AVMEDIA_TYPE_AUDIO,
149  .p.id = AV_CODEC_ID_MP3ON4,
150  .priv_data_size = sizeof(MP3On4DecodeContext),
151  .init = decode_init_mp3on4,
152  .close = decode_close_mp3on4,
153  FF_CODEC_DECODE_CB(decode_frame_mp3on4),
154  .p.capabilities = AV_CODEC_CAP_CHANNEL_CONF |
156  .flush = flush_mp3on4,
157  .p.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
159  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
160 };
161 #endif
AV_SAMPLE_FMT_FLTP
@ AV_SAMPLE_FMT_FLTP
float, planar
Definition: samplefmt.h:66
FF_CODEC_CAP_INIT_CLEANUP
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: codec_internal.h:43
decode_frame
static int decode_frame(AVCodecContext *avctx, AVFrame *picture, int *got_frame, AVPacket *avpkt)
Definition: 4xm.c:836
AV_CODEC_ID_MP3ON4
@ AV_CODEC_ID_MP3ON4
Definition: codec_id.h:460
FFCodec
Definition: codec_internal.h:127
MPADecodeContext
Definition: mpegaudiodec_template.c:77
ff_mp3on4float_decoder
const FFCodec ff_mp3on4float_decoder
AV_CODEC_ID_MP3ADU
@ AV_CODEC_ID_MP3ADU
Definition: codec_id.h:459
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
csa_table
static const float csa_table[8][4]
Definition: mpegaudiodec_float.c:55
samplefmt.h
AV_CODEC_ID_MP3
@ AV_CODEC_ID_MP3
preferred ID for decoding MPEG audio layer 1, 2 or 3
Definition: codec_id.h:447
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:311
mpegaudiodec_template.c
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AV_CODEC_ID_MP2
@ AV_CODEC_ID_MP2
Definition: codec_id.h:446
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:296
flush
void(* flush)(AVBSFContext *ctx)
Definition: dts2pts.c:370
ff_mp2float_decoder
const FFCodec ff_mp2float_decoder
AV_CODEC_CAP_CHANNEL_CONF
#define AV_CODEC_CAP_CHANNEL_CONF
Codec should fill in channel configuration and samplerate instead of container.
Definition: codec.h:106
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:368
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
codec_internal.h
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:56
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
ff_mp1float_decoder
const FFCodec ff_mp1float_decoder
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: 4xm.c:994
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
ff_mp3adufloat_decoder
const FFCodec ff_mp3adufloat_decoder
mpegaudio.h
ff_mp3float_decoder
const FFCodec ff_mp3float_decoder
is_table
static const float is_table[2][16]
Definition: mpegaudiodec_float.c:43
AV_CODEC_ID_MP1
@ AV_CODEC_ID_MP1
Definition: codec_id.h:488
AV_SAMPLE_FMT_FLT
@ AV_SAMPLE_FMT_FLT
float
Definition: samplefmt.h:60