FFmpeg/libavcodec/libilbc.c

196 lines
5.8 KiB
C

/*
* iLBC decoder/encoder stub
* Copyright (c) 2012 Martin Storsjo
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <ilbc.h>
#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "libavutil/opt.h"
#include "avcodec.h"
#include "internal.h"
static int get_mode(AVCodecContext *avctx)
{
if (avctx->block_align == 38)
return 20;
else if (avctx->block_align == 50)
return 30;
else if (avctx->bit_rate > 0)
return avctx->bit_rate <= 14000 ? 30 : 20;
else
return -1;
}
typedef struct ILBCDecContext {
const AVClass *class;
iLBC_Dec_Inst_t decoder;
int enhance;
} ILBCDecContext;
static const AVOption ilbc_dec_options[] = {
{ "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 },
{ NULL }
};
static const AVClass ilbc_dec_class = {
"libilbc", av_default_item_name, ilbc_dec_options, LIBAVUTIL_VERSION_INT
};
static av_cold int ilbc_decode_init(AVCodecContext *avctx)
{
ILBCDecContext *s = avctx->priv_data;
int mode;
if ((mode = get_mode(avctx)) < 0) {
av_log(avctx, AV_LOG_ERROR, "iLBC frame mode not indicated\n");
return AVERROR(EINVAL);
}
WebRtcIlbcfix_InitDecode(&s->decoder, mode, s->enhance);
avctx->channels = 1;
avctx->channel_layout = AV_CH_LAYOUT_MONO;
avctx->sample_rate = 8000;
avctx->sample_fmt = AV_SAMPLE_FMT_S16;
return 0;
}
static int ilbc_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame_ptr, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
ILBCDecContext *s = avctx->priv_data;
AVFrame *frame = data;
int ret;
if (s->decoder.no_of_bytes > buf_size) {
av_log(avctx, AV_LOG_ERROR, "iLBC frame too short (%u, should be %u)\n",
buf_size, s->decoder.no_of_bytes);
return AVERROR_INVALIDDATA;
}
frame->nb_samples = s->decoder.blockl;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
}
WebRtcIlbcfix_DecodeImpl((WebRtc_Word16*) frame->data[0],
(const WebRtc_UWord16*) buf, &s->decoder, 1);
*got_frame_ptr = 1;
return s->decoder.no_of_bytes;
}
AVCodec ff_libilbc_decoder = {
.name = "libilbc",
.long_name = NULL_IF_CONFIG_SMALL("iLBC (Internet Low Bitrate Codec)"),
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_ILBC,
.priv_data_size = sizeof(ILBCDecContext),
.init = ilbc_decode_init,
.decode = ilbc_decode_frame,
.capabilities = CODEC_CAP_DR1,
.priv_class = &ilbc_dec_class,
};
typedef struct ILBCEncContext {
const AVClass *class;
iLBC_Enc_Inst_t encoder;
int mode;
} ILBCEncContext;
static const AVOption ilbc_enc_options[] = {
{ "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 },
{ NULL }
};
static const AVClass ilbc_enc_class = {
"libilbc", av_default_item_name, ilbc_enc_options, LIBAVUTIL_VERSION_INT
};
static av_cold int ilbc_encode_init(AVCodecContext *avctx)
{
ILBCEncContext *s = avctx->priv_data;
int mode;
if (avctx->sample_rate != 8000) {
av_log(avctx, AV_LOG_ERROR, "Only 8000Hz sample rate supported\n");
return AVERROR(EINVAL);
}
if (avctx->channels != 1) {
av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");
return AVERROR(EINVAL);
}
if ((mode = get_mode(avctx)) > 0)
s->mode = mode;
else
s->mode = s->mode != 30 ? 20 : 30;
WebRtcIlbcfix_InitEncode(&s->encoder, s->mode);
avctx->block_align = s->encoder.no_of_bytes;
avctx->frame_size = s->encoder.blockl;
return 0;
}
static int ilbc_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
const AVFrame *frame, int *got_packet_ptr)
{
ILBCEncContext *s = avctx->priv_data;
int ret;
if ((ret = ff_alloc_packet(avpkt, 50))) {
av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
return ret;
}
WebRtcIlbcfix_EncodeImpl((WebRtc_UWord16*) avpkt->data, (const WebRtc_Word16*) frame->data[0], &s->encoder);
avpkt->size = s->encoder.no_of_bytes;
*got_packet_ptr = 1;
return 0;
}
static const AVCodecDefault ilbc_encode_defaults[] = {
{ "b", "0" },
{ NULL }
};
AVCodec ff_libilbc_encoder = {
.name = "libilbc",
.long_name = NULL_IF_CONFIG_SMALL("iLBC (Internet Low Bitrate Codec)"),
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_ILBC,
.priv_data_size = sizeof(ILBCEncContext),
.init = ilbc_encode_init,
.encode2 = ilbc_encode_frame,
.sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
AV_SAMPLE_FMT_NONE },
.defaults = ilbc_encode_defaults,
.priv_class = &ilbc_enc_class,
};