[deb_ffmpeg.git] / ffmpeg / libavformat / spdifdec.c

/*
 * 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 (avio_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,
};
Commit	Line	Data
2ba45a60 DM	1	/*
	2	* IEC 61937 demuxer
	3	* Copyright (c) 2010 Anssi Hannula <anssi.hannula at iki.fi>
	4	*
	5	* This file is part of FFmpeg.
	6	*
	7	* FFmpeg is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU Lesser General Public
	9	* License as published by the Free Software Foundation; either
	10	* version 2.1 of the License, or (at your option) any later version.
	11	*
	12	* FFmpeg is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	15	* Lesser General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU Lesser General Public
	18	* License along with FFmpeg; if not, write to the Free Software
	19	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	20	*/
	21
	22	/**
	23	* @file
	24	* IEC 61937 demuxer, used for compressed data in S/PDIF
	25	* @author Anssi Hannula
	26	*/
	27
	28	#include "avformat.h"
	29	#include "spdif.h"
	30	#include "libavcodec/ac3.h"
	31	#include "libavcodec/aacadtsdec.h"
	32
	33	static int spdif_get_offset_and_codec(AVFormatContext *s,
	34	enum IEC61937DataType data_type,
	35	const char buf, int offset,
	36	enum AVCodecID *codec)
	37	{
	38	AACADTSHeaderInfo aac_hdr;
	39	GetBitContext gbc;
	40
	41	switch (data_type & 0xff) {
	42	case IEC61937_AC3:
	43	*offset = AC3_FRAME_SIZE << 2;
	44	*codec = AV_CODEC_ID_AC3;
	45	break;
	46	case IEC61937_MPEG1_LAYER1:
	47	*offset = spdif_mpeg_pkt_offset[1][0];
	48	*codec = AV_CODEC_ID_MP1;
	49	break;
	50	case IEC61937_MPEG1_LAYER23:
	51	*offset = spdif_mpeg_pkt_offset[1][0];
	52	*codec = AV_CODEC_ID_MP3;
	53	break;
	54	case IEC61937_MPEG2_EXT:
	55	*offset = 4608;
	56	*codec = AV_CODEC_ID_MP3;
	57	break;
	58	case IEC61937_MPEG2_AAC:
	59	init_get_bits(&gbc, buf, AAC_ADTS_HEADER_SIZE * 8);
	60	if (avpriv_aac_parse_header(&gbc, &aac_hdr) < 0) {
	61	if (s) /* be silent during a probe */
	62	av_log(s, AV_LOG_ERROR, "Invalid AAC packet in IEC 61937\n");
	63	return AVERROR_INVALIDDATA;
	64	}
65	*offset = aac_hdr.samples << 2;
66	*codec = AV_CODEC_ID_AAC;
67	break;
68	case IEC61937_MPEG2_LAYER1_LSF:
69	*offset = spdif_mpeg_pkt_offset[0][0];
70	*codec = AV_CODEC_ID_MP1;
71	break;
72	case IEC61937_MPEG2_LAYER2_LSF:
73	*offset = spdif_mpeg_pkt_offset[0][1];
74	*codec = AV_CODEC_ID_MP2;
75	break;
76	case IEC61937_MPEG2_LAYER3_LSF:
77	*offset = spdif_mpeg_pkt_offset[0][2];
78	*codec = AV_CODEC_ID_MP3;
79	break;
80	case IEC61937_DTS1:
81	*offset = 2048;
82	*codec = AV_CODEC_ID_DTS;
83	break;
84	case IEC61937_DTS2:
85	*offset = 4096;
86	*codec = AV_CODEC_ID_DTS;
87	break;
88	case IEC61937_DTS3:
89	*offset = 8192;
90	*codec = AV_CODEC_ID_DTS;
91	break;
92	default:
93	if (s) { /* be silent during a probe */
94	avpriv_request_sample(s, "Data type 0x%04x in IEC 61937",
95	data_type);
96	}
97	return AVERROR_PATCHWELCOME;
98	}
99	return 0;
100	}
101
102	/* Largest offset between bursts we currently handle, i.e. AAC with
103	aac_hdr.samples = 4096 */
104	#define SPDIF_MAX_OFFSET 16384
105
106	static int spdif_probe(AVProbeData *p)
107	{
108	enum AVCodecID codec;
109	return ff_spdif_probe (p->buf, p->buf_size, &codec);
110	}
111
112	int ff_spdif_probe(const uint8_t p_buf, int buf_size, enum AVCodecID codec)
113	{
114	const uint8_t *buf = p_buf;
115	const uint8_t probe_end = p_buf + FFMIN(2 SPDIF_MAX_OFFSET, buf_size - 1);
116	const uint8_t *expected_code = buf + 7;
117	uint32_t state = 0;
118	int sync_codes = 0;
119	int consecutive_codes = 0;
120	int offset;
121
122	for (; buf < probe_end; buf++) {
123	state = (state << 8) \| *buf;
124
125	if (state == (AV_BSWAP16C(SYNCWORD1) << 16 \| AV_BSWAP16C(SYNCWORD2))
126	&& buf[1] < 0x37) {
127	sync_codes++;
128
129	if (buf == expected_code) {
130	if (++consecutive_codes >= 2)
131	return AVPROBE_SCORE_MAX;
132	} else
133	consecutive_codes = 0;
134
135	if (buf + 4 + AAC_ADTS_HEADER_SIZE > p_buf + buf_size)
136	break;
137
138	/* continue probing to find more sync codes */
139	probe_end = FFMIN(buf + SPDIF_MAX_OFFSET, p_buf + buf_size - 1);
140
141	/* skip directly to the next sync code */
142	if (!spdif_get_offset_and_codec(NULL, (buf[2] << 8) \| buf[1],
143	&buf[5], &offset, codec)) {
144	if (buf + offset >= p_buf + buf_size)
145	break;
146	expected_code = buf + offset;
147	buf = expected_code - 7;
148	}
149	}
150	}
151
152	if (!sync_codes)
153	return 0;
154
155	if (sync_codes >= 6)
156	/* good amount of sync codes but with unexpected offsets */
157	return AVPROBE_SCORE_EXTENSION;
158
159	/* some sync codes were found */
160	return AVPROBE_SCORE_EXTENSION / 4;
161	}
162
163	static int spdif_read_header(AVFormatContext *s)
164	{
165	s->ctx_flags \|= AVFMTCTX_NOHEADER;
166	return 0;
167	}
168
169	int ff_spdif_read_packet(AVFormatContext s, AVPacket pkt)
170	{
171	AVIOContext *pb = s->pb;
172	enum IEC61937DataType data_type;
173	enum AVCodecID codec_id;
174	uint32_t state = 0;
175	int pkt_size_bits, offset, ret;
176
177	while (state != (AV_BSWAP16C(SYNCWORD1) << 16 \| AV_BSWAP16C(SYNCWORD2))) {
178	state = (state << 8) \| avio_r8(pb);
179	if (avio_feof(pb))
180	return AVERROR_EOF;
181	}
182
183	data_type = avio_rl16(pb);
184	pkt_size_bits = avio_rl16(pb);
185
186	if (pkt_size_bits % 16)
187	avpriv_request_sample(s, "Packet not ending at a 16-bit boundary");
188
189	ret = av_new_packet(pkt, FFALIGN(pkt_size_bits, 16) >> 3);
190	if (ret)
191	return ret;
192
193	pkt->pos = avio_tell(pb) - BURST_HEADER_SIZE;
194
195	if (avio_read(pb, pkt->data, pkt->size) < pkt->size) {
196	av_free_packet(pkt);
197	return AVERROR_EOF;
198	}
199	ff_spdif_bswap_buf16((uint16_t )pkt->data, (uint16_t )pkt->data, pkt->size >> 1);
200
201	ret = spdif_get_offset_and_codec(s, data_type, pkt->data,
202	&offset, &codec_id);
203	if (ret) {
204	av_free_packet(pkt);
205	return ret;
206	}
207
208	/* skip over the padding to the beginning of the next frame */
209	avio_skip(pb, offset - pkt->size - BURST_HEADER_SIZE);
210
211	if (!s->nb_streams) {
212	/* first packet, create a stream */
213	AVStream *st = avformat_new_stream(s, NULL);
214	if (!st) {
215	av_free_packet(pkt);
216	return AVERROR(ENOMEM);
217	}
218	st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
219	st->codec->codec_id = codec_id;
220	} else if (codec_id != s->streams[0]->codec->codec_id) {
221	avpriv_report_missing_feature(s, "Codec change in IEC 61937");
222	return AVERROR_PATCHWELCOME;
223	}
224
225	if (!s->bit_rate && s->streams[0]->codec->sample_rate)
226	/* stream bitrate matches 16-bit stereo PCM bitrate for currently
227	supported codecs */
228	s->bit_rate = 2 * 16 * s->streams[0]->codec->sample_rate;
229
230	return 0;
231	}
232
233	AVInputFormat ff_spdif_demuxer = {
234	.name = "spdif",
235	.long_name = NULL_IF_CONFIG_SMALL("IEC 61937 (compressed data in S/PDIF)"),
236	.read_probe = spdif_probe,
237	.read_header = spdif_read_header,
238	.read_packet = ff_spdif_read_packet,
239	.flags = AVFMT_GENERIC_INDEX,
240	};