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Diffstat (limited to 'ffmpeg/libavformat/spdifdec.c')
-rw-r--r--ffmpeg/libavformat/spdifdec.c240
1 files changed, 0 insertions, 240 deletions
diff --git a/ffmpeg/libavformat/spdifdec.c b/ffmpeg/libavformat/spdifdec.c
deleted file mode 100644
index 7da16c9..0000000
--- a/ffmpeg/libavformat/spdifdec.c
+++ /dev/null
@@ -1,240 +0,0 @@
-/*
- * IEC 61937 demuxer
- * Copyright (c) 2010 Anssi Hannula <anssi.hannula at iki.fi>
- *
- * 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
- * IEC 61937 demuxer, used for compressed data in S/PDIF
- * @author Anssi Hannula
- */
-
-#include "avformat.h"
-#include "spdif.h"
-#include "libavcodec/ac3.h"
-#include "libavcodec/aacadtsdec.h"
-
-static int spdif_get_offset_and_codec(AVFormatContext *s,
- enum IEC61937DataType data_type,
- const char *buf, int *offset,
- enum AVCodecID *codec)
-{
- AACADTSHeaderInfo aac_hdr;
- GetBitContext gbc;
-
- switch (data_type & 0xff) {
- case IEC61937_AC3:
- *offset = AC3_FRAME_SIZE << 2;
- *codec = AV_CODEC_ID_AC3;
- break;
- case IEC61937_MPEG1_LAYER1:
- *offset = spdif_mpeg_pkt_offset[1][0];
- *codec = AV_CODEC_ID_MP1;
- break;
- case IEC61937_MPEG1_LAYER23:
- *offset = spdif_mpeg_pkt_offset[1][0];
- *codec = AV_CODEC_ID_MP3;
- break;
- case IEC61937_MPEG2_EXT:
- *offset = 4608;
- *codec = AV_CODEC_ID_MP3;
- break;
- case IEC61937_MPEG2_AAC:
- init_get_bits(&gbc, buf, AAC_ADTS_HEADER_SIZE * 8);
- if (avpriv_aac_parse_header(&gbc, &aac_hdr) < 0) {
- if (s) /* be silent during a probe */
- av_log(s, AV_LOG_ERROR, "Invalid AAC packet in IEC 61937\n");
- return AVERROR_INVALIDDATA;
- }
- *offset = aac_hdr.samples << 2;
- *codec = AV_CODEC_ID_AAC;
- break;
- case IEC61937_MPEG2_LAYER1_LSF:
- *offset = spdif_mpeg_pkt_offset[0][0];
- *codec = AV_CODEC_ID_MP1;
- break;
- case IEC61937_MPEG2_LAYER2_LSF:
- *offset = spdif_mpeg_pkt_offset[0][1];
- *codec = AV_CODEC_ID_MP2;
- break;
- case IEC61937_MPEG2_LAYER3_LSF:
- *offset = spdif_mpeg_pkt_offset[0][2];
- *codec = AV_CODEC_ID_MP3;
- break;
- case IEC61937_DTS1:
- *offset = 2048;
- *codec = AV_CODEC_ID_DTS;
- break;
- case IEC61937_DTS2:
- *offset = 4096;
- *codec = AV_CODEC_ID_DTS;
- break;
- case IEC61937_DTS3:
- *offset = 8192;
- *codec = AV_CODEC_ID_DTS;
- break;
- default:
- if (s) { /* be silent during a probe */
- avpriv_request_sample(s, "Data type 0x%04x in IEC 61937",
- data_type);
- }
- return AVERROR_PATCHWELCOME;
- }
- return 0;
-}
-
-/* Largest offset between bursts we currently handle, i.e. AAC with
- aac_hdr.samples = 4096 */
-#define SPDIF_MAX_OFFSET 16384
-
-static int spdif_probe(AVProbeData *p)
-{
- enum AVCodecID codec;
- return ff_spdif_probe (p->buf, p->buf_size, &codec);
-}
-
-int ff_spdif_probe(const uint8_t *p_buf, int buf_size, enum AVCodecID *codec)
-{
- const uint8_t *buf = p_buf;
- const uint8_t *probe_end = p_buf + FFMIN(2 * SPDIF_MAX_OFFSET, buf_size - 1);
- const uint8_t *expected_code = buf + 7;
- uint32_t state = 0;
- int sync_codes = 0;
- int consecutive_codes = 0;
- int offset;
-
- for (; buf < probe_end; buf++) {
- state = (state << 8) | *buf;
-
- if (state == (AV_BSWAP16C(SYNCWORD1) << 16 | AV_BSWAP16C(SYNCWORD2))
- && buf[1] < 0x37) {
- sync_codes++;
-
- if (buf == expected_code) {
- if (++consecutive_codes >= 2)
- return AVPROBE_SCORE_MAX;
- } else
- consecutive_codes = 0;
-
- if (buf + 4 + AAC_ADTS_HEADER_SIZE > p_buf + buf_size)
- break;
-
- /* continue probing to find more sync codes */
- probe_end = FFMIN(buf + SPDIF_MAX_OFFSET, p_buf + buf_size - 1);
-
- /* skip directly to the next sync code */
- if (!spdif_get_offset_and_codec(NULL, (buf[2] << 8) | buf[1],
- &buf[5], &offset, codec)) {
- if (buf + offset >= p_buf + buf_size)
- break;
- expected_code = buf + offset;
- buf = expected_code - 7;
- }
- }
- }
-
- if (!sync_codes)
- return 0;
-
- if (sync_codes >= 6)
- /* good amount of sync codes but with unexpected offsets */
- return AVPROBE_SCORE_EXTENSION;
-
- /* some sync codes were found */
- return AVPROBE_SCORE_EXTENSION / 4;
-}
-
-static int spdif_read_header(AVFormatContext *s)
-{
- s->ctx_flags |= AVFMTCTX_NOHEADER;
- return 0;
-}
-
-int ff_spdif_read_packet(AVFormatContext *s, AVPacket *pkt)
-{
- AVIOContext *pb = s->pb;
- enum IEC61937DataType data_type;
- enum AVCodecID codec_id;
- uint32_t state = 0;
- int pkt_size_bits, offset, ret;
-
- while (state != (AV_BSWAP16C(SYNCWORD1) << 16 | AV_BSWAP16C(SYNCWORD2))) {
- state = (state << 8) | avio_r8(pb);
- if (url_feof(pb))
- return AVERROR_EOF;
- }
-
- data_type = avio_rl16(pb);
- pkt_size_bits = avio_rl16(pb);
-
- if (pkt_size_bits % 16)
- avpriv_request_sample(s, "Packet not ending at a 16-bit boundary");
-
- ret = av_new_packet(pkt, FFALIGN(pkt_size_bits, 16) >> 3);
- if (ret)
- return ret;
-
- pkt->pos = avio_tell(pb) - BURST_HEADER_SIZE;
-
- if (avio_read(pb, pkt->data, pkt->size) < pkt->size) {
- av_free_packet(pkt);
- return AVERROR_EOF;
- }
- ff_spdif_bswap_buf16((uint16_t *)pkt->data, (uint16_t *)pkt->data, pkt->size >> 1);
-
- ret = spdif_get_offset_and_codec(s, data_type, pkt->data,
- &offset, &codec_id);
- if (ret) {
- av_free_packet(pkt);
- return ret;
- }
-
- /* skip over the padding to the beginning of the next frame */
- avio_skip(pb, offset - pkt->size - BURST_HEADER_SIZE);
-
- if (!s->nb_streams) {
- /* first packet, create a stream */
- AVStream *st = avformat_new_stream(s, NULL);
- if (!st) {
- av_free_packet(pkt);
- return AVERROR(ENOMEM);
- }
- st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
- st->codec->codec_id = codec_id;
- } else if (codec_id != s->streams[0]->codec->codec_id) {
- avpriv_report_missing_feature(s, "Codec change in IEC 61937");
- return AVERROR_PATCHWELCOME;
- }
-
- if (!s->bit_rate && s->streams[0]->codec->sample_rate)
- /* stream bitrate matches 16-bit stereo PCM bitrate for currently
- supported codecs */
- s->bit_rate = 2 * 16 * s->streams[0]->codec->sample_rate;
-
- return 0;
-}
-
-AVInputFormat ff_spdif_demuxer = {
- .name = "spdif",
- .long_name = NULL_IF_CONFIG_SMALL("IEC 61937 (compressed data in S/PDIF)"),
- .read_probe = spdif_probe,
- .read_header = spdif_read_header,
- .read_packet = ff_spdif_read_packet,
- .flags = AVFMT_GENERIC_INDEX,
-};
generated by cgit v1.2.3 (git 2.39.1) at 2025-12-06 16:49:56 +0000