FFmpeg
mpegaudiodec_fixed.c
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1 /*
2  * Fixed-point MPEG audio decoder
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "config.h"
22 #include "libavutil/samplefmt.h"
23 
24 #define USE_FLOATS 0
25 
26 #include "mpegaudio.h"
27 
28 #define SHR(a,b) (((int)(a))>>(b))
29 /* WARNING: only correct for positive numbers */
30 #define FIXR_OLD(a) ((int)((a) * FRAC_ONE + 0.5))
31 #define FIXR(a) ((int)((a) * FRAC_ONE + 0.5))
32 #define FIXHR(a) ((int)((a) * (1LL<<32) + 0.5))
33 #define MULH3(x, y, s) MULH((s)*(x), y)
34 #define MULLx(x, y, s) MULL((int)(x),(y),s)
35 #define RENAME(a) a ## _fixed
36 #define OUT_FMT AV_SAMPLE_FMT_S16
37 #define OUT_FMT_P AV_SAMPLE_FMT_S16P
38 
39 /* Intensity stereo table. See commit b91d46614df189e7905538e7f5c4ed9c7ed0d274
40  * (float based mp1/mp2/mp3 decoders.) for how they were created. */
41 static const int32_t is_table[2][16] = {
42  { 0x000000, 0x1B0CB1, 0x2ED9EC, 0x400000, 0x512614, 0x64F34F, 0x800000 },
43  { 0x800000, 0x64F34F, 0x512614, 0x400000, 0x2ED9EC, 0x1B0CB1, 0x000000 }
44 };
45 
46 /* Antialiasing table. See commit ce4a29c066cddfc180979ed86396812f24337985
47  * (optimize antialias) for how they were created. */
48 static const int32_t csa_table[8][4] = {
49  { 0x36E129F8, 0xDF128056, 0x15F3AA4E, 0xA831565E },
50  { 0x386E75F2, 0xE1CF24A5, 0x1A3D9A97, 0xA960AEB3 },
51  { 0x3CC6B73A, 0xEBF19FA6, 0x28B856E0, 0xAF2AE86C },
52  { 0x3EEEA054, 0xF45B88BC, 0x334A2910, 0xB56CE868 },
53  { 0x3FB6905C, 0xF9F27F18, 0x39A90F74, 0xBA3BEEBC },
54  { 0x3FF23F20, 0xFD60D1E4, 0x3D531104, 0xBD6E92C4 },
55  { 0x3FFE5932, 0xFF175EE4, 0x3F15B816, 0xBF1905B2 },
56  { 0x3FFFE34A, 0xFFC3612F, 0x3FC34479, 0xBFC37DE5 }
57 };
58 
59 #include "mpegaudiodec_template.c"
60 
61 #if CONFIG_MP1_DECODER
62 const AVCodec ff_mp1_decoder = {
63  .name = "mp1",
64  .long_name = NULL_IF_CONFIG_SMALL("MP1 (MPEG audio layer 1)"),
65  .type = AVMEDIA_TYPE_AUDIO,
66  .id = AV_CODEC_ID_MP1,
67  .priv_data_size = sizeof(MPADecodeContext),
68  .init = decode_init,
70  .capabilities = AV_CODEC_CAP_CHANNEL_CONF |
72  .flush = flush,
73  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
76  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
77 };
78 #endif
79 #if CONFIG_MP2_DECODER
80 const AVCodec ff_mp2_decoder = {
81  .name = "mp2",
82  .long_name = NULL_IF_CONFIG_SMALL("MP2 (MPEG audio layer 2)"),
83  .type = AVMEDIA_TYPE_AUDIO,
84  .id = AV_CODEC_ID_MP2,
85  .priv_data_size = sizeof(MPADecodeContext),
86  .init = decode_init,
88  .capabilities = AV_CODEC_CAP_CHANNEL_CONF |
90  .flush = flush,
91  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
94  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
95 };
96 #endif
97 #if CONFIG_MP3_DECODER
98 const AVCodec ff_mp3_decoder = {
99  .name = "mp3",
100  .long_name = NULL_IF_CONFIG_SMALL("MP3 (MPEG audio layer 3)"),
101  .type = AVMEDIA_TYPE_AUDIO,
102  .id = AV_CODEC_ID_MP3,
103  .priv_data_size = sizeof(MPADecodeContext),
104  .init = decode_init,
105  .decode = decode_frame,
106  .capabilities = AV_CODEC_CAP_CHANNEL_CONF |
108  .flush = flush,
109  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
112  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
113 };
114 #endif
115 #if CONFIG_MP3ADU_DECODER
116 const AVCodec ff_mp3adu_decoder = {
117  .name = "mp3adu",
118  .long_name = NULL_IF_CONFIG_SMALL("ADU (Application Data Unit) MP3 (MPEG audio layer 3)"),
119  .type = AVMEDIA_TYPE_AUDIO,
120  .id = AV_CODEC_ID_MP3ADU,
121  .priv_data_size = sizeof(MPADecodeContext),
122  .init = decode_init,
123  .decode = decode_frame_adu,
124  .capabilities = AV_CODEC_CAP_CHANNEL_CONF |
126  .flush = flush,
127  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
130  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
131 };
132 #endif
133 #if CONFIG_MP3ON4_DECODER
134 const AVCodec ff_mp3on4_decoder = {
135  .name = "mp3on4",
136  .long_name = NULL_IF_CONFIG_SMALL("MP3onMP4"),
137  .type = AVMEDIA_TYPE_AUDIO,
138  .id = AV_CODEC_ID_MP3ON4,
139  .priv_data_size = sizeof(MP3On4DecodeContext),
140  .init = decode_init_mp3on4,
141  .close = decode_close_mp3on4,
142  .decode = decode_frame_mp3on4,
143  .capabilities = AV_CODEC_CAP_CHANNEL_CONF |
145  .flush = flush_mp3on4,
146  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
149 };
150 #endif
AVCodec
AVCodec.
Definition: codec.h:202
FF_CODEC_CAP_INIT_THREADSAFE
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:42
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:948
AV_CODEC_ID_MP3ON4
@ AV_CODEC_ID_MP3ON4
Definition: codec_id.h:437
MPADecodeContext
Definition: mpegaudiodec_template.c:74
AV_CODEC_ID_MP3ADU
@ AV_CODEC_ID_MP3ADU
Definition: codec_id.h:436
samplefmt.h
ff_mp3on4_decoder
const AVCodec ff_mp3on4_decoder
AV_CODEC_ID_MP3
@ AV_CODEC_ID_MP3
preferred ID for decoding MPEG audio layer 1, 2 or 3
Definition: codec_id.h:424
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
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:423
ff_mp3_decoder
const AVCodec ff_mp3_decoder
flush
static void flush(AVCodecContext *avctx)
Definition: aacdec_template.c:593
ff_mp2_decoder
const AVCodec ff_mp2_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:109
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
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
AV_SAMPLE_FMT_S16P
@ AV_SAMPLE_FMT_S16P
signed 16 bits, planar
Definition: samplefmt.h:67
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: internal.h:50
is_table
static const int32_t is_table[2][16]
Definition: mpegaudiodec_fixed.c:41
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
decode_init
static av_cold int decode_init(AVCodecContext *avctx)
Definition: 4xm.c:990
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:61
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:209
mpegaudio.h
decode_frame
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: 4xm.c:836
ff_mp3adu_decoder
const AVCodec ff_mp3adu_decoder
int32_t
int32_t
Definition: audioconvert.c:56
AV_CODEC_ID_MP1
@ AV_CODEC_ID_MP1
Definition: codec_id.h:465
ff_mp1_decoder
const AVCodec ff_mp1_decoder
csa_table
static const int32_t csa_table[8][4]
Definition: mpegaudiodec_fixed.c:48