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/*
* AMR Audio encoder stub
* Copyright (c) 2003 the ffmpeg project
*
* 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 <vo-amrwbenc/enc_if.h>
#include "avcodec.h"
static const char wb_bitrate_unsupported[] =
"bitrate not supported: use one of 6.6k, 8.85k, 12.65k, 14.25k, 15.85k, "
"18.25k, 19.85k, 23.05k, or 23.85k\n";
typedef struct AMRWB_bitrates {
int rate;
int mode;
} AMRWB_bitrates;
typedef struct AMRWBContext {
void *state;
int mode;
int allow_dtx;
} AMRWBContext;
static int getWBBitrateMode(int bitrate)
{
/* make the correspondance between bitrate and mode */
AMRWB_bitrates rates[] = { { 6600, 0},
{ 8850, 1},
{12650, 2},
{14250, 3},
{15850, 4},
{18250, 5},
{19850, 6},
{23050, 7},
{23850, 8}, };
int i;
for (i = 0; i < 9; i++)
if (rates[i].rate == bitrate)
return rates[i].mode;
/* no bitrate matching, return an error */
return -1;
}
static av_cold int amr_wb_encode_init(AVCodecContext *avctx)
{
AMRWBContext *s = avctx->priv_data;
if (avctx->sample_rate != 16000) {
av_log(avctx, AV_LOG_ERROR, "Only 16000Hz sample rate supported\n");
return -1;
}
if (avctx->channels != 1) {
av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");
return -1;
}
if ((s->mode = getWBBitrateMode(avctx->bit_rate)) < 0) {
av_log(avctx, AV_LOG_ERROR, wb_bitrate_unsupported);
return -1;
}
avctx->frame_size = 320;
avctx->coded_frame = avcodec_alloc_frame();
s->state = E_IF_init();
s->allow_dtx = 0;
return 0;
}
static int amr_wb_encode_close(AVCodecContext *avctx)
{
AMRWBContext *s = avctx->priv_data;
E_IF_exit(s->state);
av_freep(&avctx->coded_frame);
return 0;
}
static int amr_wb_encode_frame(AVCodecContext *avctx,
unsigned char *frame/*out*/,
int buf_size, void *data/*in*/)
{
AMRWBContext *s = avctx->priv_data;
int size;
if ((s->mode = getWBBitrateMode(avctx->bit_rate)) < 0) {
av_log(avctx, AV_LOG_ERROR, wb_bitrate_unsupported);
return -1;
}
size = E_IF_encode(s->state, s->mode, data, frame, s->allow_dtx);
return size;
}
AVCodec ff_libvo_amrwbenc_encoder = {
"libvo_amrwbenc",
CODEC_TYPE_AUDIO,
CODEC_ID_AMR_WB,
sizeof(AMRWBContext),
amr_wb_encode_init,
amr_wb_encode_frame,
amr_wb_encode_close,
NULL,
.sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE},
.long_name = NULL_IF_CONFIG_SMALL("libvo-amrwbenc Adaptive Multi-Rate "
"(AMR) Wide-Band"),
};
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