| 0,0 → 1,161 |
|---|
| /* |
| * SMPTE 302M decoder |
| * Copyright (c) 2008 Laurent Aimar <fenrir@videolan.org> |
| * Copyright (c) 2009 Baptiste Coudurier <baptiste.coudurier@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 "libavutil/intreadwrite.h" |
| #include "libavutil/log.h" |
| #include "avcodec.h" |
| #include "internal.h" |
| #include "mathops.h" |
| |
| #define AES3_HEADER_LEN 4 |
| |
| static int s302m_parse_frame_header(AVCodecContext *avctx, const uint8_t *buf, |
| int buf_size) |
| { |
| uint32_t h; |
| int frame_size, channels, bits; |
| |
| if (buf_size <= AES3_HEADER_LEN) { |
| av_log(avctx, AV_LOG_ERROR, "frame is too short\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| /* |
| * AES3 header : |
| * size: 16 |
| * number channels 2 |
| * channel_id 8 |
| * bits per samples 2 |
| * alignments 4 |
| */ |
| |
| h = AV_RB32(buf); |
| frame_size = (h >> 16) & 0xffff; |
| channels = ((h >> 14) & 0x0003) * 2 + 2; |
| bits = ((h >> 4) & 0x0003) * 4 + 16; |
| |
| if (AES3_HEADER_LEN + frame_size != buf_size || bits > 24) { |
| av_log(avctx, AV_LOG_ERROR, "frame has invalid header\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| /* Set output properties */ |
| avctx->bits_per_raw_sample = bits; |
| if (bits > 16) |
| avctx->sample_fmt = AV_SAMPLE_FMT_S32; |
| else |
| avctx->sample_fmt = AV_SAMPLE_FMT_S16; |
| |
| avctx->channels = channels; |
| switch(channels) { |
| case 2: |
| avctx->channel_layout = AV_CH_LAYOUT_STEREO; |
| break; |
| case 4: |
| avctx->channel_layout = AV_CH_LAYOUT_QUAD; |
| break; |
| case 6: |
| avctx->channel_layout = AV_CH_LAYOUT_5POINT1_BACK; |
| break; |
| case 8: |
| avctx->channel_layout = AV_CH_LAYOUT_5POINT1_BACK | AV_CH_LAYOUT_STEREO_DOWNMIX; |
| } |
| avctx->sample_rate = 48000; |
| avctx->bit_rate = 48000 * avctx->channels * (avctx->bits_per_raw_sample + 4) + |
| 32 * (48000 / (buf_size * 8 / |
| (avctx->channels * |
| (avctx->bits_per_raw_sample + 4)))); |
| |
| return frame_size; |
| } |
| |
| static int s302m_decode_frame(AVCodecContext *avctx, void *data, |
| int *got_frame_ptr, AVPacket *avpkt) |
| { |
| AVFrame *frame = data; |
| const uint8_t *buf = avpkt->data; |
| int buf_size = avpkt->size; |
| int block_size, ret; |
| |
| int frame_size = s302m_parse_frame_header(avctx, buf, buf_size); |
| if (frame_size < 0) |
| return frame_size; |
| |
| buf_size -= AES3_HEADER_LEN; |
| buf += AES3_HEADER_LEN; |
| |
| /* get output buffer */ |
| block_size = (avctx->bits_per_raw_sample + 4) / 4; |
| frame->nb_samples = 2 * (buf_size / block_size) / avctx->channels; |
| if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) |
| return ret; |
| |
| buf_size = (frame->nb_samples * avctx->channels / 2) * block_size; |
| |
| if (avctx->bits_per_raw_sample == 24) { |
| uint32_t *o = (uint32_t *)frame->data[0]; |
| for (; buf_size > 6; buf_size -= 7) { |
| *o++ = (ff_reverse[buf[2]] << 24) | |
| (ff_reverse[buf[1]] << 16) | |
| (ff_reverse[buf[0]] << 8); |
| *o++ = (ff_reverse[buf[6] & 0xf0] << 28) | |
| (ff_reverse[buf[5]] << 20) | |
| (ff_reverse[buf[4]] << 12) | |
| (ff_reverse[buf[3] & 0x0f] << 4); |
| buf += 7; |
| } |
| } else if (avctx->bits_per_raw_sample == 20) { |
| uint32_t *o = (uint32_t *)frame->data[0]; |
| for (; buf_size > 5; buf_size -= 6) { |
| *o++ = (ff_reverse[buf[2] & 0xf0] << 28) | |
| (ff_reverse[buf[1]] << 20) | |
| (ff_reverse[buf[0]] << 12); |
| *o++ = (ff_reverse[buf[5] & 0xf0] << 28) | |
| (ff_reverse[buf[4]] << 20) | |
| (ff_reverse[buf[3]] << 12); |
| buf += 6; |
| } |
| } else { |
| uint16_t *o = (uint16_t *)frame->data[0]; |
| for (; buf_size > 4; buf_size -= 5) { |
| *o++ = (ff_reverse[buf[1]] << 8) | |
| ff_reverse[buf[0]]; |
| *o++ = (ff_reverse[buf[4] & 0xf0] << 12) | |
| (ff_reverse[buf[3]] << 4) | |
| (ff_reverse[buf[2]] >> 4); |
| buf += 5; |
| } |
| } |
| |
| *got_frame_ptr = 1; |
| |
| return avpkt->size; |
| } |
| |
| AVCodec ff_s302m_decoder = { |
| .name = "s302m", |
| .long_name = NULL_IF_CONFIG_SMALL("SMPTE 302M"), |
| .type = AVMEDIA_TYPE_AUDIO, |
| .id = AV_CODEC_ID_S302M, |
| .decode = s302m_decode_frame, |
| .capabilities = CODEC_CAP_DR1, |
| }; |