3 * Copyright (c) 2008 Laurent Aimar <fenrir@videolan.org>
4 * Copyright (c) 2009 Baptiste Coudurier <baptiste.coudurier@gmail.com>
6 * This file is part of Libav.
8 * Libav is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * Libav is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with Libav; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "libavutil/intreadwrite.h"
24 #include "libavutil/log.h"
29 #define AES3_HEADER_LEN 4
31 static int s302m_parse_frame_header(AVCodecContext *avctx, const uint8_t *buf,
35 int frame_size, channels, bits;
37 if (buf_size <= AES3_HEADER_LEN) {
38 av_log(avctx, AV_LOG_ERROR, "frame is too short\n");
39 return AVERROR_INVALIDDATA;
52 frame_size = (h >> 16) & 0xffff;
53 channels = ((h >> 14) & 0x0003) * 2 + 2;
54 bits = ((h >> 4) & 0x0003) * 4 + 16;
56 if (AES3_HEADER_LEN + frame_size != buf_size || bits > 24) {
57 av_log(avctx, AV_LOG_ERROR, "frame has invalid header\n");
58 return AVERROR_INVALIDDATA;
61 /* Set output properties */
62 avctx->bits_per_coded_sample = bits;
64 avctx->sample_fmt = AV_SAMPLE_FMT_S32;
66 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
68 avctx->channels = channels;
69 avctx->sample_rate = 48000;
70 avctx->bit_rate = 48000 * avctx->channels * (avctx->bits_per_coded_sample + 4) +
71 32 * (48000 / (buf_size * 8 /
73 (avctx->bits_per_coded_sample + 4))));
78 static int s302m_decode_frame(AVCodecContext *avctx, void *data,
79 int *got_frame_ptr, AVPacket *avpkt)
81 AVFrame *frame = data;
82 const uint8_t *buf = avpkt->data;
83 int buf_size = avpkt->size;
86 int frame_size = s302m_parse_frame_header(avctx, buf, buf_size);
90 buf_size -= AES3_HEADER_LEN;
91 buf += AES3_HEADER_LEN;
93 /* get output buffer */
94 block_size = (avctx->bits_per_coded_sample + 4) / 4;
95 frame->nb_samples = 2 * (buf_size / block_size) / avctx->channels;
96 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
97 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
101 buf_size = (frame->nb_samples * avctx->channels / 2) * block_size;
103 if (avctx->bits_per_coded_sample == 24) {
104 uint32_t *o = (uint32_t *)frame->data[0];
105 for (; buf_size > 6; buf_size -= 7) {
106 *o++ = (ff_reverse[buf[2]] << 24) |
107 (ff_reverse[buf[1]] << 16) |
108 (ff_reverse[buf[0]] << 8);
109 *o++ = (ff_reverse[buf[6] & 0xf0] << 28) |
110 (ff_reverse[buf[5]] << 20) |
111 (ff_reverse[buf[4]] << 12) |
112 (ff_reverse[buf[3] & 0x0f] << 4);
115 } else if (avctx->bits_per_coded_sample == 20) {
116 uint32_t *o = (uint32_t *)frame->data[0];
117 for (; buf_size > 5; buf_size -= 6) {
118 *o++ = (ff_reverse[buf[2] & 0xf0] << 28) |
119 (ff_reverse[buf[1]] << 20) |
120 (ff_reverse[buf[0]] << 12);
121 *o++ = (ff_reverse[buf[5] & 0xf0] << 28) |
122 (ff_reverse[buf[4]] << 20) |
123 (ff_reverse[buf[3]] << 12);
127 uint16_t *o = (uint16_t *)frame->data[0];
128 for (; buf_size > 4; buf_size -= 5) {
129 *o++ = (ff_reverse[buf[1]] << 8) |
131 *o++ = (ff_reverse[buf[4] & 0xf0] << 12) |
132 (ff_reverse[buf[3]] << 4) |
133 (ff_reverse[buf[2]] >> 4);
143 AVCodec ff_s302m_decoder = {
145 .long_name = NULL_IF_CONFIG_SMALL("SMPTE 302M"),
146 .type = AVMEDIA_TYPE_AUDIO,
147 .id = AV_CODEC_ID_S302M,
148 .decode = s302m_decode_frame,
149 .capabilities = AV_CODEC_CAP_DR1,