FFmpeg
libgsmenc.c
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1 /*
2  * Interface to libgsm for GSM encoding
3  * Copyright (c) 2005 Alban Bedel <albeu@free.fr>
4  * Copyright (c) 2006, 2007 Michel Bardiaux <mbardiaux@mediaxim.be>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * Interface to libgsm for GSM encoding
26  */
27 
28 // The idiosyncrasies of GSM-in-WAV are explained at http://kbs.cs.tu-berlin.de/~jutta/toast.html
29 
30 #include "config.h"
31 #include "config_components.h"
32 #if HAVE_GSM_H
33 #include <gsm.h>
34 #else
35 #include <gsm/gsm.h>
36 #endif
37 
39 #include "libavutil/common.h"
40 
41 #include "avcodec.h"
42 #include "codec_internal.h"
43 #include "encode.h"
44 #include "gsm.h"
45 
47  gsm_destroy(avctx->priv_data);
48  avctx->priv_data = NULL;
49  return 0;
50 }
51 
53  if (avctx->sample_rate != 8000) {
54  av_log(avctx, AV_LOG_ERROR, "Sample rate 8000Hz required for GSM, got %dHz\n",
55  avctx->sample_rate);
57  return -1;
58  }
59  if (avctx->bit_rate != 13000 /* Official */ &&
60  avctx->bit_rate != 13200 /* Very common */ &&
61  avctx->bit_rate != 0 /* Unknown; a.o. mov does not set bitrate when decoding */ ) {
62  av_log(avctx, AV_LOG_ERROR, "Bitrate 13000bps required for GSM, got %"PRId64"bps\n",
63  avctx->bit_rate);
65  return -1;
66  }
67 
68  avctx->priv_data = gsm_create();
69  if (!avctx->priv_data)
70  goto error;
71 
72  switch(avctx->codec_id) {
73  case AV_CODEC_ID_GSM:
74  avctx->frame_size = GSM_FRAME_SIZE;
75  avctx->block_align = GSM_BLOCK_SIZE;
76  break;
77  case AV_CODEC_ID_GSM_MS: {
78  int one = 1;
79  gsm_option(avctx->priv_data, GSM_OPT_WAV49, &one);
80  avctx->frame_size = 2*GSM_FRAME_SIZE;
82  }
83  }
84 
85  return 0;
86 error:
87  libgsm_encode_close(avctx);
88  return -1;
89 }
90 
91 static int libgsm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
92  const AVFrame *frame, int *got_packet_ptr)
93 {
94  int ret;
95  gsm_signal *samples = (gsm_signal *)frame->data[0];
96  struct gsm_state *state = avctx->priv_data;
97 
98  if ((ret = ff_get_encode_buffer(avctx, avpkt, avctx->block_align, 0)) < 0)
99  return ret;
100 
101  switch(avctx->codec_id) {
102  case AV_CODEC_ID_GSM:
103  gsm_encode(state, samples, avpkt->data);
104  break;
105  case AV_CODEC_ID_GSM_MS:
106  gsm_encode(state, samples, avpkt->data);
107  gsm_encode(state, samples + GSM_FRAME_SIZE, avpkt->data + 32);
108  }
109 
110  *got_packet_ptr = 1;
111  return 0;
112 }
113 
114 static const FFCodecDefault libgsm_defaults[] = {
115  { "b", "13000" },
116  { NULL },
117 };
118 
119 #if CONFIG_LIBGSM_ENCODER
120 const FFCodec ff_libgsm_encoder = {
121  .p.name = "libgsm",
122  CODEC_LONG_NAME("libgsm GSM"),
123  .p.type = AVMEDIA_TYPE_AUDIO,
124  .p.id = AV_CODEC_ID_GSM,
126  .init = libgsm_encode_init,
128  .close = libgsm_encode_close,
129  .defaults = libgsm_defaults,
131  .p.ch_layouts = (const AVChannelLayout[]) { AV_CHANNEL_LAYOUT_MONO, { 0 } },
132  .p.sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
134  .p.wrapper_name = "libgsm",
135  .caps_internal = FF_CODEC_CAP_NOT_INIT_THREADSAFE,
136 };
137 #endif
138 #if CONFIG_LIBGSM_MS_ENCODER
140  .p.name = "libgsm_ms",
141  CODEC_LONG_NAME("libgsm GSM Microsoft variant"),
142  .p.type = AVMEDIA_TYPE_AUDIO,
143  .p.id = AV_CODEC_ID_GSM_MS,
145  .init = libgsm_encode_init,
147  .close = libgsm_encode_close,
148  .defaults = libgsm_defaults,
150  .p.ch_layouts = (const AVChannelLayout[]) { AV_CHANNEL_LAYOUT_MONO, { 0 } },
151  .p.sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
153  .p.wrapper_name = "libgsm",
154  .caps_internal = FF_CODEC_CAP_NOT_INIT_THREADSAFE,
155 };
156 #endif
error
static void error(const char *err)
Definition: target_bsf_fuzzer.c:31
AVCodecContext::frame_size
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1096
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1068
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:214
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
AVPacket::data
uint8_t * data
Definition: packet.h:522
encode.h
FF_CODEC_CAP_NOT_INIT_THREADSAFE
#define FF_CODEC_CAP_NOT_INIT_THREADSAFE
The codec is not known to be init-threadsafe (i.e.
Definition: codec_internal.h:34
FFCodec
Definition: codec_internal.h:127
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:361
libgsm_defaults
static const FFCodecDefault libgsm_defaults[]
Definition: libgsmenc.c:114
FFCodecDefault
Definition: codec_internal.h:97
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
GSM_FRAME_SIZE
#define GSM_FRAME_SIZE
Definition: gsm.h:30
FF_CODEC_ENCODE_CB
#define FF_CODEC_ENCODE_CB(func)
Definition: codec_internal.h:315
libgsm_encode_init
static av_cold int libgsm_encode_init(AVCodecContext *avctx)
Definition: libgsmenc.c:52
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
gsm.h
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE
#define AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE
This encoder can reorder user opaque values from input AVFrames and return them with corresponding ou...
Definition: codec.h:159
CODEC_OLD_CHANNEL_LAYOUTS
#define CODEC_OLD_CHANNEL_LAYOUTS(...)
Definition: codec_internal.h:302
state
static struct @376 state
libgsm_encode_frame
static int libgsm_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Definition: libgsmenc.c:91
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:272
frame
static AVFrame * frame
Definition: demux_decode.c:54
GSM_MS_BLOCK_SIZE
#define GSM_MS_BLOCK_SIZE
Definition: gsm.h:26
AVCodecContext::codec_id
enum AVCodecID codec_id
Definition: avcodec.h:455
if
if(ret)
Definition: filter_design.txt:179
ff_libgsm_encoder
const FFCodec ff_libgsm_encoder
NULL
#define NULL
Definition: coverity.c:32
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:495
AV_CODEC_ID_GSM
@ AV_CODEC_ID_GSM
as in Berlin toast format
Definition: codec_id.h:461
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
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:313
codec_internal.h
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:56
FF_COMPLIANCE_UNOFFICIAL
#define FF_COMPLIANCE_UNOFFICIAL
Allow unofficial extensions.
Definition: defs.h:61
ff_libgsm_ms_encoder
const FFCodec ff_libgsm_ms_encoder
GSM_BLOCK_SIZE
#define GSM_BLOCK_SIZE
Definition: gsm.h:25
common.h
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:58
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
libgsm_encode_close
static av_cold int libgsm_encode_close(AVCodecContext *avctx)
Definition: libgsmenc.c:46
avcodec.h
AV_CODEC_ID_GSM_MS
@ AV_CODEC_ID_GSM_MS
Definition: codec_id.h:473
ret
ret
Definition: filter_design.txt:187
AVCodecContext::block_align
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs.
Definition: avcodec.h:1117
AVCodecContext::strict_std_compliance
int strict_std_compliance
strictly follow the standard (MPEG-4, ...).
Definition: avcodec.h:1375
AVCodecContext
main external API structure.
Definition: avcodec.h:445
channel_layout.h
ff_get_encode_buffer
int ff_get_encode_buffer(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int flags)
Get a buffer for a packet.
Definition: encode.c:105
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:388
AVPacket
This structure stores compressed data.
Definition: packet.h:499
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27