FFmpeg  4.0
ac3dec_float.c
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1 /*
2  * AC-3 Audio Decoder
3  * This code was developed as part of Google Summer of Code 2006.
4  * E-AC-3 support was added as part of Google Summer of Code 2007.
5  *
6  * Copyright (c) 2006 Kartikey Mahendra BHATT (bhattkm at gmail dot com)
7  * Copyright (c) 2007-2008 Bartlomiej Wolowiec <bartek.wolowiec@gmail.com>
8  * Copyright (c) 2007 Justin Ruggles <justin.ruggles@gmail.com>
9  *
10  * This file is part of FFmpeg.
11  *
12  * FFmpeg is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU Lesser General Public
14  * License as published by the Free Software Foundation; either
15  * version 2.1 of the License, or (at your option) any later version.
16  *
17  * FFmpeg is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20  * Lesser General Public License for more details.
21  *
22  * You should have received a copy of the GNU Lesser General Public
23  * License along with FFmpeg; if not, write to the Free Software
24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25  */
26 
27 /**
28  * Upmix delay samples from stereo to original channel layout.
29  */
30 #include "ac3dec.h"
31 #include "eac3dec.c"
32 #include "ac3dec.c"
33 
34 static const AVOption options[] = {
35  { "cons_noisegen", "enable consistent noise generation", OFFSET(consistent_noise_generation), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, PAR },
36  { "drc_scale", "percentage of dynamic range compression to apply", OFFSET(drc_scale), AV_OPT_TYPE_FLOAT, {.dbl = 1.0}, 0.0, 6.0, PAR },
37  { "heavy_compr", "enable heavy dynamic range compression", OFFSET(heavy_compression), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, PAR },
38  { "target_level", "target level in -dBFS (0 not applied)", OFFSET(target_level), AV_OPT_TYPE_INT, {.i64 = 0 }, -31, 0, PAR },
39 
40 {"dmix_mode", "Preferred Stereo Downmix Mode", OFFSET(preferred_stereo_downmix), AV_OPT_TYPE_INT, {.i64 = -1 }, -1, 2, 0, "dmix_mode"},
41 {"ltrt_cmixlev", "Lt/Rt Center Mix Level", OFFSET(ltrt_center_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, 0},
42 {"ltrt_surmixlev", "Lt/Rt Surround Mix Level", OFFSET(ltrt_surround_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, 0},
43 {"loro_cmixlev", "Lo/Ro Center Mix Level", OFFSET(loro_center_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, 0},
44 {"loro_surmixlev", "Lo/Ro Surround Mix Level", OFFSET(loro_surround_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, 0},
45 
46  { NULL},
47 };
48 
49 static const AVClass ac3_decoder_class = {
50  .class_name = "AC3 decoder",
51  .item_name = av_default_item_name,
52  .option = options,
53  .version = LIBAVUTIL_VERSION_INT,
54 };
55 
57  .name = "ac3",
58  .type = AVMEDIA_TYPE_AUDIO,
59  .id = AV_CODEC_ID_AC3,
60  .priv_data_size = sizeof (AC3DecodeContext),
62  .close = ac3_decode_end,
64  .capabilities = AV_CODEC_CAP_DR1,
65  .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"),
66  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
68  .priv_class = &ac3_decoder_class,
69 };
70 
71 #if CONFIG_EAC3_DECODER
72 static const AVClass eac3_decoder_class = {
73  .class_name = "E-AC3 decoder",
74  .item_name = av_default_item_name,
75  .option = options,
76  .version = LIBAVUTIL_VERSION_INT,
77 };
78 
80  .name = "eac3",
81  .type = AVMEDIA_TYPE_AUDIO,
82  .id = AV_CODEC_ID_EAC3,
83  .priv_data_size = sizeof (AC3DecodeContext),
85  .close = ac3_decode_end,
87  .capabilities = AV_CODEC_CAP_DR1,
88  .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52B (AC-3, E-AC-3)"),
89  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
91  .priv_class = &eac3_decoder_class,
92 };
93 #endif
float, planar
Definition: samplefmt.h:69
#define NULL
Definition: coverity.c:32
AVCodec ff_ac3_decoder
Definition: ac3dec_float.c:56
AVOption.
Definition: opt.h:246
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
AVCodec.
Definition: avcodec.h:3408
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
static av_cold int ac3_decode_end(AVCodecContext *avctx)
Uninitialize the AC-3 decoder.
Definition: ac3dec.c:1809
static const AVOption options[]
Upmix delay samples from stereo to original channel layout.
Definition: ac3dec_float.c:34
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * name
Name of the codec implementation.
Definition: avcodec.h:3415
static int ac3_decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Decode a single AC-3 frame.
Definition: ac3dec.c:1481
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
Describe the class of an AVClass context structure.
Definition: log.h:67
Definition: af_afade.c:60
static const AVClass ac3_decoder_class
Definition: ac3dec_float.c:49
AVCodec ff_eac3_decoder
#define OFFSET(x)
Definition: ffmpeg_opt.c:3291
static av_cold int ac3_decode_init(AVCodecContext *avctx)
AVCodec initialization.
Definition: ac3dec.c:203
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:959