mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-29 10:52:20 +00:00
312 lines
12 KiB
C
312 lines
12 KiB
C
/*
|
|
* LPCM codecs for PCM formats found in MPEG streams
|
|
* Copyright (c) 2009 Christian Schmidt
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* PCM codecs for encodings found in MPEG streams (DVD/Blu-ray)
|
|
*/
|
|
|
|
#include "libavutil/audioconvert.h"
|
|
#include "avcodec.h"
|
|
#include "bytestream.h"
|
|
|
|
/*
|
|
* Channel Mapping according to
|
|
* Blu-ray Disc Read-Only Format Version 1
|
|
* Part 3: Audio Visual Basic Specifications
|
|
* mono M1 X
|
|
* stereo L R
|
|
* 3/0 L R C X
|
|
* 2/1 L R S X
|
|
* 3/1 L R C S
|
|
* 2/2 L R LS RS
|
|
* 3/2 L R C LS RS X
|
|
* 3/2+lfe L R C LS RS lfe
|
|
* 3/4 L R C LS Rls Rrs RS X
|
|
* 3/4+lfe L R C LS Rls Rrs RS lfe
|
|
*/
|
|
|
|
/**
|
|
* Parse the header of a LPCM frame read from a MPEG-TS stream
|
|
* @param avctx the codec context
|
|
* @param header pointer to the first four bytes of the data packet
|
|
*/
|
|
static int pcm_bluray_parse_header(AVCodecContext *avctx,
|
|
const uint8_t *header)
|
|
{
|
|
static const uint8_t bits_per_samples[4] = { 0, 16, 20, 24 };
|
|
static const uint32_t channel_layouts[16] = {
|
|
0, AV_CH_LAYOUT_MONO, 0, AV_CH_LAYOUT_STEREO, AV_CH_LAYOUT_SURROUND,
|
|
AV_CH_LAYOUT_2_1, AV_CH_LAYOUT_4POINT0, AV_CH_LAYOUT_2_2, AV_CH_LAYOUT_5POINT0,
|
|
AV_CH_LAYOUT_5POINT1, AV_CH_LAYOUT_7POINT0, AV_CH_LAYOUT_7POINT1, 0, 0, 0, 0
|
|
};
|
|
static const uint8_t channels[16] = {
|
|
0, 1, 0, 2, 3, 3, 4, 4, 5, 6, 7, 8, 0, 0, 0, 0
|
|
};
|
|
uint8_t channel_layout = header[2] >> 4;
|
|
|
|
if (avctx->debug & FF_DEBUG_PICT_INFO)
|
|
av_dlog(avctx, "pcm_bluray_parse_header: header = %02x%02x%02x%02x\n",
|
|
header[0], header[1], header[2], header[3]);
|
|
|
|
/* get the sample depth and derive the sample format from it */
|
|
avctx->bits_per_coded_sample = bits_per_samples[header[3] >> 6];
|
|
if (!avctx->bits_per_coded_sample) {
|
|
av_log(avctx, AV_LOG_ERROR, "unsupported sample depth (0)\n");
|
|
return -1;
|
|
}
|
|
avctx->sample_fmt = avctx->bits_per_coded_sample == 16 ? AV_SAMPLE_FMT_S16 :
|
|
AV_SAMPLE_FMT_S32;
|
|
|
|
/* get the sample rate. Not all values are known or exist. */
|
|
switch (header[2] & 0x0f) {
|
|
case 1:
|
|
avctx->sample_rate = 48000;
|
|
break;
|
|
case 4:
|
|
avctx->sample_rate = 96000;
|
|
break;
|
|
case 5:
|
|
avctx->sample_rate = 192000;
|
|
break;
|
|
default:
|
|
avctx->sample_rate = 0;
|
|
av_log(avctx, AV_LOG_ERROR, "unsupported sample rate (%d)\n",
|
|
header[2] & 0x0f);
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* get the channel number (and mapping). Not all values are known or exist.
|
|
* It must be noted that the number of channels in the MPEG stream can
|
|
* differ from the actual meaningful number, e.g. mono audio still has two
|
|
* channels, one being empty.
|
|
*/
|
|
avctx->channel_layout = channel_layouts[channel_layout];
|
|
avctx->channels = channels[channel_layout];
|
|
if (!avctx->channels) {
|
|
av_log(avctx, AV_LOG_ERROR, "unsupported channel configuration (%d)\n",
|
|
channel_layout);
|
|
return -1;
|
|
}
|
|
|
|
avctx->bit_rate = avctx->channels * avctx->sample_rate *
|
|
avctx->bits_per_coded_sample;
|
|
|
|
if (avctx->debug & FF_DEBUG_PICT_INFO)
|
|
av_dlog(avctx,
|
|
"pcm_bluray_parse_header: %d channels, %d bits per sample, %d kHz, %d kbit\n",
|
|
avctx->channels, avctx->bits_per_coded_sample,
|
|
avctx->sample_rate, avctx->bit_rate);
|
|
return 0;
|
|
}
|
|
|
|
static int pcm_bluray_decode_frame(AVCodecContext *avctx,
|
|
void *data,
|
|
int *data_size,
|
|
AVPacket *avpkt)
|
|
{
|
|
const uint8_t *src = avpkt->data;
|
|
int buf_size = avpkt->size;
|
|
int num_source_channels, channel, retval;
|
|
int sample_size, samples, output_size;
|
|
int16_t *dst16 = data;
|
|
int32_t *dst32 = data;
|
|
|
|
if (buf_size < 4) {
|
|
av_log(avctx, AV_LOG_ERROR, "PCM packet too small\n");
|
|
return -1;
|
|
}
|
|
|
|
if (pcm_bluray_parse_header(avctx, src))
|
|
return -1;
|
|
src += 4;
|
|
buf_size -= 4;
|
|
|
|
/* There's always an even number of channels in the source */
|
|
num_source_channels = FFALIGN(avctx->channels, 2);
|
|
sample_size = (num_source_channels * avctx->bits_per_coded_sample) >> 3;
|
|
samples = buf_size / sample_size;
|
|
|
|
output_size = samples * avctx->channels *
|
|
(avctx->sample_fmt == AV_SAMPLE_FMT_S32 ? 4 : 2);
|
|
if (output_size > *data_size) {
|
|
av_log(avctx, AV_LOG_ERROR,
|
|
"Insufficient output buffer space (%d bytes, needed %d bytes)\n",
|
|
*data_size, output_size);
|
|
return -1;
|
|
}
|
|
*data_size = output_size;
|
|
|
|
if (samples) {
|
|
switch (avctx->channel_layout) {
|
|
/* cases with same number of source and coded channels */
|
|
case AV_CH_LAYOUT_STEREO:
|
|
case AV_CH_LAYOUT_4POINT0:
|
|
case AV_CH_LAYOUT_2_2:
|
|
samples *= num_source_channels;
|
|
if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
|
|
#if HAVE_BIGENDIAN
|
|
memcpy(dst16, src, output_size);
|
|
#else
|
|
do {
|
|
*dst16++ = bytestream_get_be16(&src);
|
|
} while (--samples);
|
|
#endif
|
|
} else {
|
|
do {
|
|
*dst32++ = bytestream_get_be24(&src) << 8;
|
|
} while (--samples);
|
|
}
|
|
break;
|
|
/* cases where number of source channels = coded channels + 1 */
|
|
case AV_CH_LAYOUT_MONO:
|
|
case AV_CH_LAYOUT_SURROUND:
|
|
case AV_CH_LAYOUT_2_1:
|
|
case AV_CH_LAYOUT_5POINT0:
|
|
if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
|
|
do {
|
|
#if HAVE_BIGENDIAN
|
|
memcpy(dst16, src, avctx->channels * 2);
|
|
dst16 += avctx->channels;
|
|
src += sample_size;
|
|
#else
|
|
channel = avctx->channels;
|
|
do {
|
|
*dst16++ = bytestream_get_be16(&src);
|
|
} while (--channel);
|
|
src += 2;
|
|
#endif
|
|
} while (--samples);
|
|
} else {
|
|
do {
|
|
channel = avctx->channels;
|
|
do {
|
|
*dst32++ = bytestream_get_be24(&src) << 8;
|
|
} while (--channel);
|
|
src += 3;
|
|
} while (--samples);
|
|
}
|
|
break;
|
|
/* remapping: L, R, C, LBack, RBack, LF */
|
|
case AV_CH_LAYOUT_5POINT1:
|
|
if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
|
|
do {
|
|
dst16[0] = bytestream_get_be16(&src);
|
|
dst16[1] = bytestream_get_be16(&src);
|
|
dst16[2] = bytestream_get_be16(&src);
|
|
dst16[4] = bytestream_get_be16(&src);
|
|
dst16[5] = bytestream_get_be16(&src);
|
|
dst16[3] = bytestream_get_be16(&src);
|
|
dst16 += 6;
|
|
} while (--samples);
|
|
} else {
|
|
do {
|
|
dst32[0] = bytestream_get_be24(&src) << 8;
|
|
dst32[1] = bytestream_get_be24(&src) << 8;
|
|
dst32[2] = bytestream_get_be24(&src) << 8;
|
|
dst32[4] = bytestream_get_be24(&src) << 8;
|
|
dst32[5] = bytestream_get_be24(&src) << 8;
|
|
dst32[3] = bytestream_get_be24(&src) << 8;
|
|
dst32 += 6;
|
|
} while (--samples);
|
|
}
|
|
break;
|
|
/* remapping: L, R, C, LSide, LBack, RBack, RSide, <unused> */
|
|
case AV_CH_LAYOUT_7POINT0:
|
|
if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
|
|
do {
|
|
dst16[0] = bytestream_get_be16(&src);
|
|
dst16[1] = bytestream_get_be16(&src);
|
|
dst16[2] = bytestream_get_be16(&src);
|
|
dst16[5] = bytestream_get_be16(&src);
|
|
dst16[3] = bytestream_get_be16(&src);
|
|
dst16[4] = bytestream_get_be16(&src);
|
|
dst16[6] = bytestream_get_be16(&src);
|
|
dst16 += 7;
|
|
src += 2;
|
|
} while (--samples);
|
|
} else {
|
|
do {
|
|
dst32[0] = bytestream_get_be24(&src) << 8;
|
|
dst32[1] = bytestream_get_be24(&src) << 8;
|
|
dst32[2] = bytestream_get_be24(&src) << 8;
|
|
dst32[5] = bytestream_get_be24(&src) << 8;
|
|
dst32[3] = bytestream_get_be24(&src) << 8;
|
|
dst32[4] = bytestream_get_be24(&src) << 8;
|
|
dst32[6] = bytestream_get_be24(&src) << 8;
|
|
dst32 += 7;
|
|
src += 3;
|
|
} while (--samples);
|
|
}
|
|
break;
|
|
/* remapping: L, R, C, LSide, LBack, RBack, RSide, LF */
|
|
case AV_CH_LAYOUT_7POINT1:
|
|
if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
|
|
do {
|
|
dst16[0] = bytestream_get_be16(&src);
|
|
dst16[1] = bytestream_get_be16(&src);
|
|
dst16[2] = bytestream_get_be16(&src);
|
|
dst16[6] = bytestream_get_be16(&src);
|
|
dst16[4] = bytestream_get_be16(&src);
|
|
dst16[5] = bytestream_get_be16(&src);
|
|
dst16[7] = bytestream_get_be16(&src);
|
|
dst16[3] = bytestream_get_be16(&src);
|
|
dst16 += 8;
|
|
} while (--samples);
|
|
} else {
|
|
do {
|
|
dst32[0] = bytestream_get_be24(&src) << 8;
|
|
dst32[1] = bytestream_get_be24(&src) << 8;
|
|
dst32[2] = bytestream_get_be24(&src) << 8;
|
|
dst32[6] = bytestream_get_be24(&src) << 8;
|
|
dst32[4] = bytestream_get_be24(&src) << 8;
|
|
dst32[5] = bytestream_get_be24(&src) << 8;
|
|
dst32[7] = bytestream_get_be24(&src) << 8;
|
|
dst32[3] = bytestream_get_be24(&src) << 8;
|
|
dst32 += 8;
|
|
} while (--samples);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
retval = src - avpkt->data;
|
|
if (avctx->debug & FF_DEBUG_BITSTREAM)
|
|
av_dlog(avctx, "pcm_bluray_decode_frame: decoded %d -> %d bytes\n",
|
|
retval, *data_size);
|
|
return retval;
|
|
}
|
|
|
|
AVCodec ff_pcm_bluray_decoder = {
|
|
"pcm_bluray",
|
|
AVMEDIA_TYPE_AUDIO,
|
|
CODEC_ID_PCM_BLURAY,
|
|
0,
|
|
NULL,
|
|
NULL,
|
|
NULL,
|
|
pcm_bluray_decode_frame,
|
|
.sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32,
|
|
AV_SAMPLE_FMT_NONE},
|
|
.long_name = NULL_IF_CONFIG_SMALL("PCM signed 16|20|24-bit big-endian for Blu-ray media"),
|
|
};
|