ffmpeg/libavcodec/libspeexdec.c

186 lines
6.0 KiB
C

/*
* Copyright (C) 2008 David Conrad
*
* 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 <speex/speex.h>
#include <speex/speex_header.h>
#include <speex/speex_stereo.h>
#include <speex/speex_callbacks.h>
#include "libavutil/audioconvert.h"
#include "libavutil/common.h"
#include "avcodec.h"
typedef struct {
AVFrame frame;
SpeexBits bits;
SpeexStereoState stereo;
void *dec_state;
int frame_size;
} LibSpeexContext;
static av_cold int libspeex_decode_init(AVCodecContext *avctx)
{
LibSpeexContext *s = avctx->priv_data;
const SpeexMode *mode;
SpeexHeader *header = NULL;
int spx_mode;
avctx->sample_fmt = AV_SAMPLE_FMT_S16;
if (avctx->extradata && avctx->extradata_size >= 80) {
header = speex_packet_to_header(avctx->extradata,
avctx->extradata_size);
if (!header)
av_log(avctx, AV_LOG_WARNING, "Invalid Speex header\n");
}
if (header) {
avctx->channels = header->nb_channels;
spx_mode = header->mode;
speex_header_free(header);
} else {
switch (avctx->sample_rate) {
case 8000: spx_mode = 0; break;
case 16000: spx_mode = 1; break;
case 32000: spx_mode = 2; break;
default:
/* libspeex can handle any mode if initialized as ultra-wideband */
av_log(avctx, AV_LOG_WARNING, "Invalid sample rate: %d\n"
"Decoding as 32kHz ultra-wideband\n",
avctx->sample_rate);
spx_mode = 2;
}
}
mode = speex_lib_get_mode(spx_mode);
if (!mode) {
av_log(avctx, AV_LOG_ERROR, "Unknown Speex mode %d", spx_mode);
return AVERROR_INVALIDDATA;
}
avctx->sample_rate = 8000 << spx_mode;
s->frame_size = 160 << spx_mode;
if (avctx->channels < 1 || avctx->channels > 2) {
/* libspeex can handle mono or stereo if initialized as stereo */
av_log(avctx, AV_LOG_ERROR, "Invalid channel count: %d.\n"
"Decoding as stereo.\n", avctx->channels);
avctx->channels = 2;
}
avctx->channel_layout = avctx->channels == 2 ? AV_CH_LAYOUT_STEREO :
AV_CH_LAYOUT_MONO;
speex_bits_init(&s->bits);
s->dec_state = speex_decoder_init(mode);
if (!s->dec_state) {
av_log(avctx, AV_LOG_ERROR, "Error initializing libspeex decoder.\n");
return -1;
}
if (avctx->channels == 2) {
SpeexCallback callback;
callback.callback_id = SPEEX_INBAND_STEREO;
callback.func = speex_std_stereo_request_handler;
callback.data = &s->stereo;
s->stereo = (SpeexStereoState)SPEEX_STEREO_STATE_INIT;
speex_decoder_ctl(s->dec_state, SPEEX_SET_HANDLER, &callback);
}
avcodec_get_frame_defaults(&s->frame);
avctx->coded_frame = &s->frame;
return 0;
}
static int libspeex_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame_ptr, AVPacket *avpkt)
{
uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
LibSpeexContext *s = avctx->priv_data;
int16_t *output;
int ret, consumed = 0;
/* get output buffer */
s->frame.nb_samples = s->frame_size;
if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
}
output = (int16_t *)s->frame.data[0];
/* if there is not enough data left for the smallest possible frame or the
next 5 bits are a terminator code, reset the libspeex buffer using the
current packet, otherwise ignore the current packet and keep decoding
frames from the libspeex buffer. */
if (speex_bits_remaining(&s->bits) < 5 ||
speex_bits_peek_unsigned(&s->bits, 5) == 0x1F) {
/* check for flush packet */
if (!buf || !buf_size) {
*got_frame_ptr = 0;
return buf_size;
}
/* set new buffer */
speex_bits_read_from(&s->bits, buf, buf_size);
consumed = buf_size;
}
/* decode a single frame */
ret = speex_decode_int(s->dec_state, &s->bits, output);
if (ret <= -2) {
av_log(avctx, AV_LOG_ERROR, "Error decoding Speex frame.\n");
return AVERROR_INVALIDDATA;
}
if (avctx->channels == 2)
speex_decode_stereo_int(output, s->frame_size, &s->stereo);
*got_frame_ptr = 1;
*(AVFrame *)data = s->frame;
return consumed;
}
static av_cold int libspeex_decode_close(AVCodecContext *avctx)
{
LibSpeexContext *s = avctx->priv_data;
speex_bits_destroy(&s->bits);
speex_decoder_destroy(s->dec_state);
return 0;
}
static av_cold void libspeex_decode_flush(AVCodecContext *avctx)
{
LibSpeexContext *s = avctx->priv_data;
speex_bits_reset(&s->bits);
}
AVCodec ff_libspeex_decoder = {
.name = "libspeex",
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_SPEEX,
.priv_data_size = sizeof(LibSpeexContext),
.init = libspeex_decode_init,
.close = libspeex_decode_close,
.decode = libspeex_decode_frame,
.flush = libspeex_decode_flush,
.capabilities = CODEC_CAP_SUBFRAMES | CODEC_CAP_DELAY | CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("libspeex Speex"),
};