FFmpeg  1.2.12
libilbc.c
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1 /*
2  * iLBC decoder/encoder stub
3  * Copyright (c) 2012 Martin Storsjo
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 <ilbc.h>
23 
24 #include "libavutil/channel_layout.h"
25 #include "libavutil/common.h"
26 #include "libavutil/opt.h"
27 #include "avcodec.h"
28 #include "internal.h"
29 
30 static int get_mode(AVCodecContext *avctx)
31 {
32  if (avctx->block_align == 38)
33  return 20;
34  else if (avctx->block_align == 50)
35  return 30;
36  else if (avctx->bit_rate > 0)
37  return avctx->bit_rate <= 14000 ? 30 : 20;
38  else
39  return -1;
40 }
41 
42 typedef struct ILBCDecContext {
43  const AVClass *class;
44  iLBC_Dec_Inst_t decoder;
45  int enhance;
47 
48 static const AVOption ilbc_dec_options[] = {
49  { "enhance", "Enhance the decoded audio (adds delay)", offsetof(ILBCDecContext, enhance), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_DECODING_PARAM },
50  { NULL }
51 };
52 
53 static const AVClass ilbc_dec_class = {
54  .class_name = "libilbc",
55  .item_name = av_default_item_name,
56  .option = ilbc_dec_options,
57  .version = LIBAVUTIL_VERSION_INT,
58 };
59 
61 {
62  ILBCDecContext *s = avctx->priv_data;
63  int mode;
64 
65  if ((mode = get_mode(avctx)) < 0) {
66  av_log(avctx, AV_LOG_ERROR, "iLBC frame mode not indicated\n");
67  return AVERROR(EINVAL);
68  }
69 
70  WebRtcIlbcfix_InitDecode(&s->decoder, mode, s->enhance);
71 
72  avctx->channels = 1;
74  avctx->sample_rate = 8000;
76 
77  return 0;
78 }
79 
80 static int ilbc_decode_frame(AVCodecContext *avctx, void *data,
81  int *got_frame_ptr, AVPacket *avpkt)
82 {
83  const uint8_t *buf = avpkt->data;
84  int buf_size = avpkt->size;
85  ILBCDecContext *s = avctx->priv_data;
86  AVFrame *frame = data;
87  int ret;
88 
89  if (s->decoder.no_of_bytes > buf_size) {
90  av_log(avctx, AV_LOG_ERROR, "iLBC frame too short (%u, should be %u)\n",
91  buf_size, s->decoder.no_of_bytes);
92  return AVERROR_INVALIDDATA;
93  }
94 
95  frame->nb_samples = s->decoder.blockl;
96  if ((ret = ff_get_buffer(avctx, frame)) < 0) {
97  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
98  return ret;
99  }
100 
101  WebRtcIlbcfix_DecodeImpl((int16_t *) frame->data[0], (const uint16_t *) buf, &s->decoder, 1);
102 
103  *got_frame_ptr = 1;
104 
105  return s->decoder.no_of_bytes;
106 }
107 
109  .name = "libilbc",
110  .type = AVMEDIA_TYPE_AUDIO,
111  .id = AV_CODEC_ID_ILBC,
112  .priv_data_size = sizeof(ILBCDecContext),
115  .capabilities = CODEC_CAP_DR1,
116  .long_name = NULL_IF_CONFIG_SMALL("iLBC (Internet Low Bitrate Codec)"),
117  .priv_class = &ilbc_dec_class,
118 };
119 
120 typedef struct ILBCEncContext {
121  const AVClass *class;
122  iLBC_Enc_Inst_t encoder;
123  int mode;
125 
126 static const AVOption ilbc_enc_options[] = {
127  { "mode", "iLBC mode (20 or 30 ms frames)", offsetof(ILBCEncContext, mode), AV_OPT_TYPE_INT, { .i64 = 20 }, 20, 30, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM },
128  { NULL }
129 };
130 
131 static const AVClass ilbc_enc_class = {
132  .class_name = "libilbc",
133  .item_name = av_default_item_name,
134  .option = ilbc_enc_options,
135  .version = LIBAVUTIL_VERSION_INT,
136 };
137 
139 {
140  ILBCEncContext *s = avctx->priv_data;
141  int mode;
142 
143  if (avctx->sample_rate != 8000) {
144  av_log(avctx, AV_LOG_ERROR, "Only 8000Hz sample rate supported\n");
145  return AVERROR(EINVAL);
146  }
147 
148  if (avctx->channels != 1) {
149  av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");
150  return AVERROR(EINVAL);
151  }
152 
153  if ((mode = get_mode(avctx)) > 0)
154  s->mode = mode;
155  else
156  s->mode = s->mode != 30 ? 20 : 30;
157  WebRtcIlbcfix_InitEncode(&s->encoder, s->mode);
158 
159  avctx->block_align = s->encoder.no_of_bytes;
160  avctx->frame_size = s->encoder.blockl;
161 #if FF_API_OLD_ENCODE_AUDIO
162  avctx->coded_frame = avcodec_alloc_frame();
163  if (!avctx->coded_frame)
164  return AVERROR(ENOMEM);
165 #endif
166 
167  return 0;
168 }
169 
171 {
172 #if FF_API_OLD_ENCODE_AUDIO
173  av_freep(&avctx->coded_frame);
174 #endif
175  return 0;
176 }
177 
178 static int ilbc_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
179  const AVFrame *frame, int *got_packet_ptr)
180 {
181  ILBCEncContext *s = avctx->priv_data;
182  int ret;
183 
184  if ((ret = ff_alloc_packet2(avctx, avpkt, 50)) < 0)
185  return ret;
186 
187  WebRtcIlbcfix_EncodeImpl((uint16_t *) avpkt->data, (const int16_t *) frame->data[0], &s->encoder);
188 
189  avpkt->size = s->encoder.no_of_bytes;
190  *got_packet_ptr = 1;
191  return 0;
192 }
193 
195  { "b", "0" },
196  { NULL }
197 };
198 
200  .name = "libilbc",
201  .type = AVMEDIA_TYPE_AUDIO,
202  .id = AV_CODEC_ID_ILBC,
203  .priv_data_size = sizeof(ILBCEncContext),
205  .encode2 = ilbc_encode_frame,
207  .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
209  .long_name = NULL_IF_CONFIG_SMALL("iLBC (Internet Low Bitrate Codec)"),
210  .defaults = ilbc_encode_defaults,
211  .priv_class = &ilbc_enc_class,
212 };