From 062cd5a975ff7bd6fb91f9b4d1d9d102a7545499 Mon Sep 17 00:00:00 2001 From: Oleksij Rempel Date: Fri, 13 Feb 2015 08:36:17 +0100 Subject: lavf: Add DSS demuxer Signed-off-by: Oleksij Rempel Signed-off-by: Luca Barbato Signed-off-by: Vittorio Giovara --- libavformat/dss.c | 342 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 342 insertions(+) create mode 100644 libavformat/dss.c (limited to 'libavformat/dss.c') diff --git a/libavformat/dss.c b/libavformat/dss.c new file mode 100644 index 0000000000..f7d0ead1c2 --- /dev/null +++ b/libavformat/dss.c @@ -0,0 +1,342 @@ +/* + * Digital Speech Standard (DSS) demuxer + * Copyright (c) 2014 Oleksij Rempel + * + * This file is part of Libav. + * + * Libav 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. + * + * Libav 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 Libav; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include "libavutil/attributes.h" +#include "libavutil/bswap.h" +#include "libavutil/channel_layout.h" +#include "libavutil/intreadwrite.h" + +#include "avformat.h" +#include "internal.h" + +#define DSS_HEAD_OFFSET_AUTHOR 0xc +#define DSS_AUTHOR_SIZE 16 + +#define DSS_HEAD_OFFSET_START_TIME 0x26 +#define DSS_HEAD_OFFSET_END_TIME 0x32 +#define DSS_TIME_SIZE 12 + +#define DSS_HEAD_OFFSET_ACODEC 0x2a4 +#define DSS_ACODEC_DSS_SP 0x0 /* SP mode */ +#define DSS_ACODEC_G723_1 0x2 /* LP mode */ + +#define DSS_HEAD_OFFSET_COMMENT 0x31e +#define DSS_COMMENT_SIZE 64 + +#define DSS_BLOCK_SIZE 512 +#define DSS_HEADER_SIZE (DSS_BLOCK_SIZE * 2) +#define DSS_AUDIO_BLOCK_HEADER_SIZE 6 +#define DSS_FRAME_SIZE 42 + +static const uint8_t frame_size[4] = { 24, 20, 4, 1 }; + +typedef struct DSSDemuxContext { + unsigned int audio_codec; + int counter; + int swap; + int dss_sp_swap_byte; + int8_t *dss_sp_buf; +} DSSDemuxContext; + +static int dss_probe(AVProbeData *p) +{ + if (AV_RL32(p->buf) != MKTAG(0x2, 'd', 's', 's')) + return 0; + + return AVPROBE_SCORE_MAX; +} + +static int dss_read_metadata_date(AVFormatContext *s, unsigned int offset, + const char *key) +{ + AVIOContext *pb = s->pb; + char datetime[64], string[DSS_TIME_SIZE + 1] = { 0 }; + int y, month, d, h, minute, sec; + int ret; + + avio_seek(pb, offset, SEEK_SET); + + ret = avio_read(s->pb, string, DSS_TIME_SIZE); + if (ret < DSS_TIME_SIZE) + return ret < 0 ? ret : AVERROR_EOF; + + sscanf(string, "%2d%2d%2d%2d%2d%2d", &y, &month, &d, &h, &minute, &sec); + /* We deal with a two-digit year here, so set the default date to 2000 + * and hope it will never be used in the next century. */ + snprintf(datetime, sizeof(datetime), "%.4d-%.2d-%.2dT%.2d:%.2d:%.2d", + y + 2000, month, d, h, minute, sec); + return av_dict_set(&s->metadata, key, datetime, 0); +} + +static int dss_read_metadata_string(AVFormatContext *s, unsigned int offset, + unsigned int size, const char *key) +{ + AVIOContext *pb = s->pb; + char *value; + int ret; + + avio_seek(pb, offset, SEEK_SET); + + value = av_mallocz(size + 1); + if (!value) + return AVERROR(ENOMEM); + + ret = avio_read(s->pb, value, size); + if (ret < size) { + ret = ret < 0 ? ret : AVERROR_EOF; + goto exit; + } + + ret = av_dict_set(&s->metadata, key, value, 0); + +exit: + av_free(value); + return ret; +} + +static int dss_read_header(AVFormatContext *s) +{ + DSSDemuxContext *ctx = s->priv_data; + AVIOContext *pb = s->pb; + AVStream *st; + int ret; + + st = avformat_new_stream(s, NULL); + if (!st) + return AVERROR(ENOMEM); + + ret = dss_read_metadata_string(s, DSS_HEAD_OFFSET_AUTHOR, + DSS_AUTHOR_SIZE, "author"); + if (ret) + return ret; + + ret = dss_read_metadata_date(s, DSS_HEAD_OFFSET_END_TIME, "date"); + if (ret) + return ret; + + ret = dss_read_metadata_string(s, DSS_HEAD_OFFSET_COMMENT, + DSS_COMMENT_SIZE, "comment"); + if (ret) + return ret; + + avio_seek(pb, DSS_HEAD_OFFSET_ACODEC, SEEK_SET); + ctx->audio_codec = avio_r8(pb); + + if (ctx->audio_codec == DSS_ACODEC_DSS_SP) { + st->codec->codec_id = AV_CODEC_ID_DSS_SP; + st->codec->sample_rate = 12000; + } else if (ctx->audio_codec == DSS_ACODEC_G723_1) { + st->codec->codec_id = AV_CODEC_ID_G723_1; + st->codec->sample_rate = 8000; + } else { + avpriv_request_sample(s, "Support for codec %x in DSS", + ctx->audio_codec); + return AVERROR_PATCHWELCOME; + } + + st->codec->codec_type = AVMEDIA_TYPE_AUDIO; + st->codec->channel_layout = AV_CH_LAYOUT_MONO; + st->codec->channels = 1; + + avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate); + st->start_time = 0; + + /* Jump over header */ + + if (avio_seek(pb, DSS_HEADER_SIZE, SEEK_SET) != DSS_HEADER_SIZE) + return AVERROR(EIO); + + ctx->counter = 0; + ctx->swap = 0; + + ctx->dss_sp_buf = av_malloc(DSS_FRAME_SIZE + 1); + if (!ctx->dss_sp_buf) + return AVERROR(ENOMEM); + + return 0; +} + +static void dss_skip_audio_header(AVFormatContext *s, AVPacket *pkt) +{ + DSSDemuxContext *ctx = s->priv_data; + AVIOContext *pb = s->pb; + + avio_skip(pb, DSS_AUDIO_BLOCK_HEADER_SIZE); + ctx->counter += DSS_BLOCK_SIZE - DSS_AUDIO_BLOCK_HEADER_SIZE; +} + +static void dss_sp_byte_swap(DSSDemuxContext *ctx, + uint8_t *dst, const uint8_t *src) +{ + int i; + + if (ctx->swap) { + for (i = 3; i < DSS_FRAME_SIZE; i += 2) + dst[i] = src[i]; + + for (i = 0; i < DSS_FRAME_SIZE - 2; i += 2) + dst[i] = src[i + 4]; + + dst[1] = ctx->dss_sp_swap_byte; + } else { + memcpy(dst, src, DSS_FRAME_SIZE); + ctx->dss_sp_swap_byte = src[DSS_FRAME_SIZE - 2]; + } + + /* make sure byte 40 is always 0 */ + dst[DSS_FRAME_SIZE - 2] = 0; + ctx->swap ^= 1; +} + +static int dss_sp_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + DSSDemuxContext *ctx = s->priv_data; + int read_size, ret, offset = 0, buff_offset = 0; + + if (ctx->counter == 0) + dss_skip_audio_header(s, pkt); + + pkt->pos = avio_tell(s->pb); + + if (ctx->swap) { + read_size = DSS_FRAME_SIZE - 2; + buff_offset = 3; + } else + read_size = DSS_FRAME_SIZE; + + ctx->counter -= read_size; + + ret = av_new_packet(pkt, DSS_FRAME_SIZE); + if (ret < 0) + return ret; + + pkt->duration = 0; + pkt->stream_index = 0; + + if (ctx->counter < 0) { + int size2 = ctx->counter + read_size; + + ret = avio_read(s->pb, ctx->dss_sp_buf + offset + buff_offset, + size2 - offset); + if (ret < size2 - offset) + goto error_eof; + + dss_skip_audio_header(s, pkt); + offset = size2; + } + + ret = avio_read(s->pb, ctx->dss_sp_buf + offset + buff_offset, + read_size - offset); + if (ret < read_size - offset) + goto error_eof; + + dss_sp_byte_swap(ctx, pkt->data, ctx->dss_sp_buf); + + if (pkt->data[0] == 0xff) + return AVERROR_INVALIDDATA; + + return pkt->size; + +error_eof: + av_free_packet(pkt); + return ret < 0 ? ret : AVERROR_EOF; +} + +static int dss_723_1_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + DSSDemuxContext *ctx = s->priv_data; + int size, byte, ret, offset; + + if (ctx->counter == 0) + dss_skip_audio_header(s, pkt); + + pkt->pos = avio_tell(s->pb); + /* We make one byte-step here. Don't forget to add offset. */ + byte = avio_r8(s->pb); + if (byte == 0xff) + return AVERROR_INVALIDDATA; + + size = frame_size[byte & 3]; + + ctx->counter -= size; + + ret = av_new_packet(pkt, size); + if (ret < 0) + return ret; + + pkt->data[0] = byte; + offset = 1; + pkt->duration = 240; + + pkt->stream_index = 0; + + if (ctx->counter < 0) { + int size2 = ctx->counter + size; + + ret = avio_read(s->pb, pkt->data + offset, + size2 - offset); + if (ret < size2 - offset) { + av_free_packet(pkt); + return ret < 0 ? ret : AVERROR_EOF; + } + + dss_skip_audio_header(s, pkt); + offset = size2; + } + + ret = avio_read(s->pb, pkt->data + offset, size - offset); + if (ret < size - offset) { + av_free_packet(pkt); + return ret < 0 ? ret : AVERROR_EOF; + } + + return pkt->size; +} + +static int dss_read_packet(AVFormatContext *s, AVPacket *pkt) +{ + DSSDemuxContext *ctx = s->priv_data; + + if (ctx->audio_codec == DSS_ACODEC_DSS_SP) + return dss_sp_read_packet(s, pkt); + else + return dss_723_1_read_packet(s, pkt); +} + +static int dss_read_close(AVFormatContext *s) +{ + DSSDemuxContext *ctx = s->priv_data; + + av_free(ctx->dss_sp_buf); + + return 0; +} + +AVInputFormat ff_dss_demuxer = { + .name = "dss", + .long_name = NULL_IF_CONFIG_SMALL("Digital Speech Standard (DSS)"), + .priv_data_size = sizeof(DSSDemuxContext), + .read_probe = dss_probe, + .read_header = dss_read_header, + .read_packet = dss_read_packet, + .read_close = dss_read_close, + .extensions = "dss" +}; -- cgit v1.2.3