189 lines
7.2 KiB
C
189 lines
7.2 KiB
C
|
/*
|
||
|
|
* SMPTE 302M encoder
|
||
|
|
* Copyright (c) 2010 Google, Inc.
|
||
|
|
* Copyright (c) 2013 Darryl Wallace <wallacdj@gmail.com>
|
||
|
|
*
|
||
|
|
* 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 "avcodec.h"
|
||
|
|
#include "internal.h"
|
||
|
|
#include "mathops.h"
|
||
|
|
#include "put_bits.h"
|
||
|
|
|
||
|
|
#define AES3_HEADER_LEN 4
|
||
|
|
|
||
|
|
typedef struct S302MEncContext {
|
||
|
|
uint8_t framing_index; /* Set for even channels on multiple of 192 samples */
|
||
|
|
} S302MEncContext;
|
||
|
|
|
||
|
|
static av_cold int s302m_encode_init(AVCodecContext *avctx)
|
||
|
|
{
|
||
|
|
S302MEncContext *s = avctx->priv_data;
|
||
|
|
|
||
|
|
if (avctx->channels & 1 || avctx->channels > 8) {
|
||
|
|
av_log(avctx, AV_LOG_ERROR,
|
||
|
|
"Encoding %d channel(s) is not allowed. Only 2, 4, 6 and 8 channels are supported.\n",
|
||
|
|
avctx->channels);
|
||
|
|
return AVERROR(EINVAL);
|
||
|
|
}
|
||
|
|
|
||
|
|
switch (avctx->sample_fmt) {
|
||
|
|
case AV_SAMPLE_FMT_S16:
|
||
|
|
avctx->bits_per_raw_sample = 16;
|
||
|
|
break;
|
||
|
|
case AV_SAMPLE_FMT_S32:
|
||
|
|
if (avctx->bits_per_raw_sample > 20) {
|
||
|
|
if (avctx->bits_per_raw_sample > 24)
|
||
|
|
av_log(avctx, AV_LOG_WARNING, "encoding as 24 bits-per-sample\n");
|
||
|
|
avctx->bits_per_raw_sample = 24;
|
||
|
|
} else if (!avctx->bits_per_raw_sample) {
|
||
|
|
avctx->bits_per_raw_sample = 24;
|
||
|
|
} else if (avctx->bits_per_raw_sample <= 20) {
|
||
|
|
avctx->bits_per_raw_sample = 20;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
avctx->frame_size = 0;
|
||
|
|
avctx->bit_rate = 48000 * avctx->channels *
|
||
|
|
(avctx->bits_per_raw_sample + 4);
|
||
|
|
s->framing_index = 0;
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int s302m_encode2_frame(AVCodecContext *avctx, AVPacket *avpkt,
|
||
|
|
const AVFrame *frame, int *got_packet_ptr)
|
||
|
|
{
|
||
|
|
S302MEncContext *s = avctx->priv_data;
|
||
|
|
const int buf_size = AES3_HEADER_LEN +
|
||
|
|
(frame->nb_samples *
|
||
|
|
avctx->channels *
|
||
|
|
(avctx->bits_per_raw_sample + 4)) / 8;
|
||
|
|
int ret, c, channels;
|
||
|
|
uint8_t *o;
|
||
|
|
PutBitContext pb;
|
||
|
|
|
||
|
|
if (buf_size - AES3_HEADER_LEN > UINT16_MAX) {
|
||
|
|
av_log(avctx, AV_LOG_ERROR, "number of samples in frame too big\n");
|
||
|
|
return AVERROR(EINVAL);
|
||
|
|
}
|
||
|
|
|
||
|
|
if ((ret = ff_alloc_packet2(avctx, avpkt, buf_size, 0)) < 0)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
o = avpkt->data;
|
||
|
|
init_put_bits(&pb, o, buf_size);
|
||
|
|
put_bits(&pb, 16, buf_size - AES3_HEADER_LEN);
|
||
|
|
put_bits(&pb, 2, (avctx->channels - 2) >> 1); // number of channels
|
||
|
|
put_bits(&pb, 8, 0); // channel ID
|
||
|
|
put_bits(&pb, 2, (avctx->bits_per_raw_sample - 16) / 4); // bits per samples (0 = 16bit, 1 = 20bit, 2 = 24bit)
|
||
|
|
put_bits(&pb, 4, 0); // alignments
|
||
|
|
flush_put_bits(&pb);
|
||
|
|
o += AES3_HEADER_LEN;
|
||
|
|
|
||
|
|
if (avctx->bits_per_raw_sample == 24) {
|
||
|
|
const uint32_t *samples = (uint32_t *)frame->data[0];
|
||
|
|
|
||
|
|
for (c = 0; c < frame->nb_samples; c++) {
|
||
|
|
uint8_t vucf = s->framing_index == 0 ? 0x10: 0;
|
||
|
|
|
||
|
|
for (channels = 0; channels < avctx->channels; channels += 2) {
|
||
|
|
o[0] = ff_reverse[(samples[0] & 0x0000FF00) >> 8];
|
||
|
|
o[1] = ff_reverse[(samples[0] & 0x00FF0000) >> 16];
|
||
|
|
o[2] = ff_reverse[(samples[0] & 0xFF000000) >> 24];
|
||
|
|
o[3] = ff_reverse[(samples[1] & 0x00000F00) >> 4] | vucf;
|
||
|
|
o[4] = ff_reverse[(samples[1] & 0x000FF000) >> 12];
|
||
|
|
o[5] = ff_reverse[(samples[1] & 0x0FF00000) >> 20];
|
||
|
|
o[6] = ff_reverse[(samples[1] & 0xF0000000) >> 28];
|
||
|
|
o += 7;
|
||
|
|
samples += 2;
|
||
|
|
}
|
||
|
|
|
||
|
|
s->framing_index++;
|
||
|
|
if (s->framing_index >= 192)
|
||
|
|
s->framing_index = 0;
|
||
|
|
}
|
||
|
|
} else if (avctx->bits_per_raw_sample == 20) {
|
||
|
|
const uint32_t *samples = (uint32_t *)frame->data[0];
|
||
|
|
|
||
|
|
for (c = 0; c < frame->nb_samples; c++) {
|
||
|
|
uint8_t vucf = s->framing_index == 0 ? 0x80: 0;
|
||
|
|
|
||
|
|
for (channels = 0; channels < avctx->channels; channels += 2) {
|
||
|
|
o[0] = ff_reverse[ (samples[0] & 0x000FF000) >> 12];
|
||
|
|
o[1] = ff_reverse[ (samples[0] & 0x0FF00000) >> 20];
|
||
|
|
o[2] = ff_reverse[((samples[0] & 0xF0000000) >> 28) | vucf];
|
||
|
|
o[3] = ff_reverse[ (samples[1] & 0x000FF000) >> 12];
|
||
|
|
o[4] = ff_reverse[ (samples[1] & 0x0FF00000) >> 20];
|
||
|
|
o[5] = ff_reverse[ (samples[1] & 0xF0000000) >> 28];
|
||
|
|
o += 6;
|
||
|
|
samples += 2;
|
||
|
|
}
|
||
|
|
|
||
|
|
s->framing_index++;
|
||
|
|
if (s->framing_index >= 192)
|
||
|
|
s->framing_index = 0;
|
||
|
|
}
|
||
|
|
} else if (avctx->bits_per_raw_sample == 16) {
|
||
|
|
const uint16_t *samples = (uint16_t *)frame->data[0];
|
||
|
|
|
||
|
|
for (c = 0; c < frame->nb_samples; c++) {
|
||
|
|
uint8_t vucf = s->framing_index == 0 ? 0x10 : 0;
|
||
|
|
|
||
|
|
for (channels = 0; channels < avctx->channels; channels += 2) {
|
||
|
|
o[0] = ff_reverse[ samples[0] & 0xFF];
|
||
|
|
o[1] = ff_reverse[(samples[0] & 0xFF00) >> 8];
|
||
|
|
o[2] = ff_reverse[(samples[1] & 0x0F) << 4] | vucf;
|
||
|
|
o[3] = ff_reverse[(samples[1] & 0x0FF0) >> 4];
|
||
|
|
o[4] = ff_reverse[(samples[1] & 0xF000) >> 12];
|
||
|
|
o += 5;
|
||
|
|
samples += 2;
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
s->framing_index++;
|
||
|
|
if (s->framing_index >= 192)
|
||
|
|
s->framing_index = 0;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
*got_packet_ptr = 1;
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
AVCodec ff_s302m_encoder = {
|
||
|
|
.name = "s302m",
|
||
|
|
.long_name = NULL_IF_CONFIG_SMALL("SMPTE 302M"),
|
||
|
|
.type = AVMEDIA_TYPE_AUDIO,
|
||
|
|
.id = AV_CODEC_ID_S302M,
|
||
|
|
.priv_data_size = sizeof(S302MEncContext),
|
||
|
|
.init = s302m_encode_init,
|
||
|
|
.encode2 = s302m_encode2_frame,
|
||
|
|
.sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S32,
|
||
|
|
AV_SAMPLE_FMT_S16,
|
||
|
|
AV_SAMPLE_FMT_NONE },
|
||
|
|
.capabilities = AV_CODEC_CAP_VARIABLE_FRAME_SIZE | AV_CODEC_CAP_EXPERIMENTAL,
|
||
|
|
.supported_samplerates = (const int[]) { 48000, 0 },
|
||
|
|
/* .channel_layouts = (const uint64_t[]) { AV_CH_LAYOUT_STEREO,
|
||
|
|
AV_CH_LAYOUT_QUAD,
|
||
|
|
AV_CH_LAYOUT_5POINT1_BACK,
|
||
|
|
AV_CH_LAYOUT_5POINT1_BACK | AV_CH_LAYOUT_STEREO_DOWNMIX,
|
||
|
|
0 }, */
|
||
|
|
};
|