| /* |
| * Digital Speech Standard (DSS) demuxer |
| * Copyright (c) 2014 Oleksij Rempel <linux@rempel-privat.de> |
| * |
| * 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/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; |
| |
| int packet_size; |
| } 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; |
| |
| if (sscanf(string, "%2d%2d%2d%2d%2d%2d", &y, &month, &d, &h, &minute, &sec) != 6) |
| return AVERROR_INVALIDDATA; |
| /* 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 = 11025; |
| } 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; |
| AVStream *st = s->streams[0]; |
| int read_size, ret, offset = 0, buff_offset = 0; |
| int64_t pos = avio_tell(s->pb); |
| |
| if (ctx->counter == 0) |
| dss_skip_audio_header(s, pkt); |
| |
| if (ctx->swap) { |
| read_size = DSS_FRAME_SIZE - 2; |
| buff_offset = 3; |
| } else |
| read_size = DSS_FRAME_SIZE; |
| |
| ctx->counter -= read_size; |
| ctx->packet_size = DSS_FRAME_SIZE - 1; |
| |
| ret = av_new_packet(pkt, DSS_FRAME_SIZE); |
| if (ret < 0) |
| return ret; |
| |
| pkt->duration = 264; |
| pkt->pos = pos; |
| pkt->stream_index = 0; |
| s->bit_rate = 8LL * ctx->packet_size * st->codec->sample_rate * 512 / (506 * pkt->duration); |
| |
| 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 (ctx->dss_sp_swap_byte < 0) { |
| ret = AVERROR(EAGAIN); |
| goto error_eof; |
| } |
| |
| if (pkt->data[0] == 0xff) |
| return AVERROR_INVALIDDATA; |
| |
| return pkt->size; |
| |
| error_eof: |
| av_packet_unref(pkt); |
| return ret < 0 ? ret : AVERROR_EOF; |
| } |
| |
| static int dss_723_1_read_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| DSSDemuxContext *ctx = s->priv_data; |
| AVStream *st = s->streams[0]; |
| int size, byte, ret, offset; |
| int64_t pos = avio_tell(s->pb); |
| |
| if (ctx->counter == 0) |
| dss_skip_audio_header(s, pkt); |
| |
| /* 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->packet_size = size; |
| ctx->counter -= size; |
| |
| ret = av_new_packet(pkt, size); |
| if (ret < 0) |
| return ret; |
| pkt->pos = pos; |
| |
| pkt->data[0] = byte; |
| offset = 1; |
| pkt->duration = 240; |
| s->bit_rate = 8LL * size * st->codec->sample_rate * 512 / (506 * pkt->duration); |
| |
| 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_packet_unref(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_packet_unref(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_freep(&ctx->dss_sp_buf); |
| |
| return 0; |
| } |
| |
| static int dss_read_seek(AVFormatContext *s, int stream_index, |
| int64_t timestamp, int flags) |
| { |
| DSSDemuxContext *ctx = s->priv_data; |
| int64_t ret, seekto; |
| uint8_t header[DSS_AUDIO_BLOCK_HEADER_SIZE]; |
| int offset; |
| |
| if (ctx->audio_codec == DSS_ACODEC_DSS_SP) |
| seekto = timestamp / 264 * 41 / 506 * 512; |
| else |
| seekto = timestamp / 240 * ctx->packet_size / 506 * 512; |
| |
| if (seekto < 0) |
| seekto = 0; |
| |
| seekto += DSS_HEADER_SIZE; |
| |
| ret = avio_seek(s->pb, seekto, SEEK_SET); |
| if (ret < 0) |
| return ret; |
| |
| avio_read(s->pb, header, DSS_AUDIO_BLOCK_HEADER_SIZE); |
| ctx->swap = !!(header[0] & 0x80); |
| offset = 2*header[1] + 2*ctx->swap; |
| if (offset < DSS_AUDIO_BLOCK_HEADER_SIZE) |
| return AVERROR_INVALIDDATA; |
| if (offset == DSS_AUDIO_BLOCK_HEADER_SIZE) { |
| ctx->counter = 0; |
| offset = avio_skip(s->pb, -DSS_AUDIO_BLOCK_HEADER_SIZE); |
| } else { |
| ctx->counter = DSS_BLOCK_SIZE - offset; |
| offset = avio_skip(s->pb, offset - DSS_AUDIO_BLOCK_HEADER_SIZE); |
| } |
| ctx->dss_sp_swap_byte = -1; |
| 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, |
| .read_seek = dss_read_seek, |
| .extensions = "dss" |
| }; |