ffmpeg/libavcodec/libspeexenc.c

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/*
* Copyright (c) 2009 by Xuggle Incorporated. All rights reserved.
* This file is part of FFmpeg.
*
* FFmpeg 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.
*
* FFmpeg 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 FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <libavcodec/avcodec.h>
#include <speex/speex.h>
#include <speex/speex_header.h>
#include <speex/speex_stereo.h>
typedef struct {
SpeexBits bits;
void *enc_state;
SpeexHeader header;
} LibSpeexEncContext;
static av_cold int libspeex_encode_init(AVCodecContext *avctx)
{
LibSpeexEncContext *s = (LibSpeexEncContext*)avctx->priv_data;
const SpeexMode *mode;
if ((avctx->sample_fmt != SAMPLE_FMT_S16 && avctx->sample_fmt != SAMPLE_FMT_FLT) ||
avctx->sample_rate <= 0 ||
avctx->channels <= 0 ||
avctx->channels > 2)
{
av_log(avctx, AV_LOG_ERROR, "Unsupported sample format, rate, or channels for speex");
return -1;
}
if (avctx->sample_rate <= 8000)
mode = &speex_nb_mode;
else if (avctx->sample_rate <= 16000)
mode = &speex_wb_mode;
else
mode = &speex_uwb_mode;
speex_bits_init(&s->bits);
s->enc_state = speex_encoder_init(mode);
if (!s->enc_state)
{
av_log(avctx, AV_LOG_ERROR, "could not initialize speex encoder");
return -1;
}
// initialize the header
speex_init_header(&s->header, avctx->sample_rate,
avctx->channels, mode);
// TODO: It'd be nice to support VBR here, but
// I'm uncertain what AVCodecContext options to use
// to signal whether to turn it on.
if (avctx->flags & CODEC_FLAG_QSCALE) {
spx_int32_t quality = 0;
// Map global_quality's mpeg 1/2/4 scale into Speex's 0-10 scale
if (avctx->global_quality > FF_LAMBDA_MAX)
quality = 0; // lowest possible quality
else
quality = (spx_int32_t)((FF_LAMBDA_MAX-avctx->global_quality)*10.0/FF_LAMBDA_MAX);
speex_encoder_ctl(s->enc_state, SPEEX_SET_QUALITY, &quality);
} else {
// default to CBR
if (avctx->bit_rate > 0)
speex_encoder_ctl(s->enc_state, SPEEX_SET_BITRATE, &avctx->bit_rate);
// otherwise just take the default quality setting
}
// reset the bit-rate to the actual bit rate speex will use
speex_encoder_ctl(s->enc_state, SPEEX_GET_BITRATE, &s->header.bitrate);
avctx->bit_rate = s->header.bitrate;
// get the actual sample rate
speex_encoder_ctl(s->enc_state, SPEEX_GET_SAMPLING_RATE, &s->header.rate);
avctx->sample_rate = s->header.rate;
// get the frame-size. To align with FLV, we're going to put 2 frames
// per packet. If someone can tell me how to make this configurable
// from the avcodec contents, I'll mod this so it's not hard-coded.
// but without this, FLV files with speex data won't play correctly
// in flash player 10.
speex_encoder_ctl(s->enc_state, SPEEX_GET_FRAME_SIZE, &s->header.frame_size);
s->header.frames_per_packet = 2; // Need for FLV container support
avctx->frame_size = s->header.frame_size*s->header.frames_per_packet;
// and we'll put a speex header packet into extradata so that muxers
// can use it.
avctx->extradata = speex_header_to_packet(&s->header, &avctx->extradata_size);
return 0;
}
static av_cold int libspeex_encode_frame(
AVCodecContext *avctx, uint8_t *frame,
int buf_size, void *data)
{
LibSpeexEncContext *s = (LibSpeexEncContext*)avctx->priv_data;
int i = 0;
if (!data)
// nothing to flush
return 0;
speex_bits_reset(&s->bits);
for(i = 0; i < s->header.frames_per_packet; i++)
{
if (avctx->sample_fmt == SAMPLE_FMT_FLT)
{
if (avctx->channels == 2) {
speex_encode_stereo(
(float*)data+i*s->header.frame_size,
s->header.frame_size,
&s->bits);
}
speex_encode(s->enc_state,
(float*)data+i*s->header.frame_size, &s->bits);
} else {
if (avctx->channels == 2) {
speex_encode_stereo_int(
(spx_int16_t*)data+i*s->header.frame_size,
s->header.frame_size,
&s->bits);
}
speex_encode_int(s->enc_state,
(spx_int16_t*)data+i*s->header.frame_size, &s->bits);
}
}
// put in a terminator so this will fit in a OGG or FLV packet
speex_bits_insert_terminator(&s->bits);
if (buf_size >= speex_bits_nbytes(&s->bits)) {
return speex_bits_write(&s->bits, frame, buf_size);
} else {
av_log(avctx, AV_LOG_ERROR, "output buffer too small");
return -1;
}
}
static av_cold int libspeex_encode_close(AVCodecContext *avctx)
{
LibSpeexEncContext *s = (LibSpeexEncContext*)avctx->priv_data;
speex_bits_destroy(&s->bits);
speex_encoder_destroy(s->enc_state);
s->enc_state = 0;
if (avctx->extradata)
speex_header_free(avctx->extradata);
avctx->extradata = 0;
avctx->extradata_size = 0;
return 0;
}
AVCodec ff_libspeex_encoder = {
"libspeex",
AVMEDIA_TYPE_AUDIO,
CODEC_ID_SPEEX,
sizeof(LibSpeexEncContext),
libspeex_encode_init,
libspeex_encode_frame,
libspeex_encode_close,
0,
.capabilities = CODEC_CAP_DELAY,
.supported_samplerates = (const int[]){8000, 16000, 32000, 0},
.sample_fmts = (enum SampleFormat[]){SAMPLE_FMT_S16,SAMPLE_FMT_FLT,SAMPLE_FMT_NONE},
.long_name = NULL_IF_CONFIG_SMALL("libspeex Speex Encoder"),
};