/* * General DV muxer/demuxer * Copyright (c) 2003 Roman Shaposhnik * * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth * of DV technical info. * * Raw DV format * Copyright (c) 2002 Fabrice Bellard * * 50 Mbps (DVCPRO50) and 100 Mbps (DVCPRO HD) support * Copyright (c) 2006 Daniel Maas <dmaas@maasdigital.com> * Funded by BBC Research & Development * * 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 <time.h> #include "avformat.h" #include "internal.h" #include "libavcodec/dv_profile.h" #include "libavcodec/dvdata.h" #include "libavutil/channel_layout.h" #include "libavutil/intreadwrite.h" #include "libavutil/mathematics.h" #include "libavutil/timecode.h" #include "dv.h" #include "libavutil/avassert.h" struct DVDemuxContext { const DVprofile* sys; /* Current DV profile. E.g.: 525/60, 625/50 */ AVFormatContext* fctx; AVStream* vst; AVStream* ast[4]; AVPacket audio_pkt[4]; uint8_t audio_buf[4][8192]; int ach; int frames; uint64_t abytes; }; static inline uint16_t dv_audio_12to16(uint16_t sample) { uint16_t shift, result; sample = (sample < 0x800) ? sample : sample | 0xf000; shift = (sample & 0xf00) >> 8; if (shift < 0x2 || shift > 0xd) { result = sample; } else if (shift < 0x8) { shift--; result = (sample - (256 * shift)) << shift; } else { shift = 0xe - shift; result = ((sample + ((256 * shift) + 1)) << shift) - 1; } return result; } /* * This is the dumbest implementation of all -- it simply looks at * a fixed offset and if pack isn't there -- fails. We might want * to have a fallback mechanism for complete search of missing packs. */ static const uint8_t* dv_extract_pack(uint8_t* frame, enum dv_pack_type t) { int offs; switch (t) { case dv_audio_source: offs = (80*6 + 80*16*3 + 3); break; case dv_audio_control: offs = (80*6 + 80*16*4 + 3); break; case dv_video_control: offs = (80*5 + 48 + 5); break; case dv_timecode: offs = (80*1 + 3 + 3); break; default: return NULL; } return frame[offs] == t ? &frame[offs] : NULL; } static const int dv_audio_frequency[3] = { 48000, 44100, 32000, }; /* * There's a couple of assumptions being made here: * 1. By default we silence erroneous (0x8000/16bit 0x800/12bit) audio samples. * We can pass them upwards when libavcodec will be ready to deal with them. * 2. We don't do software emphasis. * 3. Audio is always returned as 16bit linear samples: 12bit nonlinear samples * are converted into 16bit linear ones. */ static int dv_extract_audio(uint8_t* frame, uint8_t* ppcm[4], const DVprofile *sys) { int size, chan, i, j, d, of, smpls, freq, quant, half_ch; uint16_t lc, rc; const uint8_t* as_pack; uint8_t *pcm, ipcm; as_pack = dv_extract_pack(frame, dv_audio_source); if (!as_pack) /* No audio ? */ return 0; smpls = as_pack[1] & 0x3f; /* samples in this frame - min. samples */ freq = (as_pack[4] >> 3) & 0x07; /* 0 - 48kHz, 1 - 44,1kHz, 2 - 32kHz */ quant = as_pack[4] & 0x07; /* 0 - 16bit linear, 1 - 12bit nonlinear */ if (quant > 1) return -1; /* unsupported quantization */ if (freq >= FF_ARRAY_ELEMS(dv_audio_frequency)) return AVERROR_INVALIDDATA; size = (sys->audio_min_samples[freq] + smpls) * 4; /* 2ch, 2bytes */ half_ch = sys->difseg_size / 2; /* We work with 720p frames split in half, thus even frames have * channels 0,1 and odd 2,3. */ ipcm = (sys->height == 720 && !(frame[1] & 0x0C)) ? 2 : 0; if (ipcm + sys->n_difchan > (quant == 1 ? 2 : 4)) { av_log(NULL, AV_LOG_ERROR, "too many dv pcm frames\n"); return AVERROR_INVALIDDATA; } /* for each DIF channel */ for (chan = 0; chan < sys->n_difchan; chan++) { av_assert0(ipcm<4); pcm = ppcm[ipcm++]; if (!pcm) break; /* for each DIF segment */ for (i = 0; i < sys->difseg_size; i++) { frame += 6 * 80; /* skip DIF segment header */ if (quant == 1 && i == half_ch) { /* next stereo channel (12bit mode only) */ av_assert0(ipcm<4); pcm = ppcm[ipcm++]; if (!pcm) break; } /* for each AV sequence */ for (j = 0; j < 9; j++) { for (d = 8; d < 80; d += 2) { if (quant == 0) { /* 16bit quantization */ of = sys->audio_shuffle[i][j] + (d - 8) / 2 * sys->audio_stride; if (of*2 >= size) continue; pcm[of*2] = frame[d+1]; // FIXME: maybe we have to admit pcm[of*2+1] = frame[d]; // that DV is a big-endian PCM if (pcm[of*2+1] == 0x80 && pcm[of*2] == 0x00) pcm[of*2+1] = 0; } else { /* 12bit quantization */ lc = ((uint16_t)frame[d] << 4) | ((uint16_t)frame[d+2] >> 4); rc = ((uint16_t)frame[d+1] << 4) | ((uint16_t)frame[d+2] & 0x0f); lc = (lc == 0x800 ? 0 : dv_audio_12to16(lc)); rc = (rc == 0x800 ? 0 : dv_audio_12to16(rc)); of = sys->audio_shuffle[i%half_ch][j] + (d - 8) / 3 * sys->audio_stride; if (of*2 >= size) continue; pcm[of*2] = lc & 0xff; // FIXME: maybe we have to admit pcm[of*2+1] = lc >> 8; // that DV is a big-endian PCM of = sys->audio_shuffle[i%half_ch+half_ch][j] + (d - 8) / 3 * sys->audio_stride; pcm[of*2] = rc & 0xff; // FIXME: maybe we have to admit pcm[of*2+1] = rc >> 8; // that DV is a big-endian PCM ++d; } } frame += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */ } } } return size; } static int dv_extract_audio_info(DVDemuxContext* c, uint8_t* frame) { const uint8_t* as_pack; int freq, stype, smpls, quant, i, ach; as_pack = dv_extract_pack(frame, dv_audio_source); if (!as_pack || !c->sys) { /* No audio ? */ c->ach = 0; return 0; } smpls = as_pack[1] & 0x3f; /* samples in this frame - min. samples */ freq = (as_pack[4] >> 3) & 0x07; /* 0 - 48kHz, 1 - 44,1kHz, 2 - 32kHz */ stype = (as_pack[3] & 0x1f); /* 0 - 2CH, 2 - 4CH, 3 - 8CH */ quant = as_pack[4] & 0x07; /* 0 - 16bit linear, 1 - 12bit nonlinear */ if (freq >= FF_ARRAY_ELEMS(dv_audio_frequency)) { av_log(c->fctx, AV_LOG_ERROR, "Unrecognized audio sample rate index (%d)\n", freq); return 0; } if (stype > 3) { av_log(c->fctx, AV_LOG_ERROR, "stype %d is invalid\n", stype); c->ach = 0; return 0; } /* note: ach counts PAIRS of channels (i.e. stereo channels) */ ach = ((int[4]){ 1, 0, 2, 4})[stype]; if (ach == 1 && quant && freq == 2) ach = 2; /* Dynamic handling of the audio streams in DV */ for (i = 0; i < ach; i++) { if (!c->ast[i]) { c->ast[i] = avformat_new_stream(c->fctx, NULL); if (!c->ast[i]) break; avpriv_set_pts_info(c->ast[i], 64, 1, 30000); c->ast[i]->codec->codec_type = AVMEDIA_TYPE_AUDIO; c->ast[i]->codec->codec_id = AV_CODEC_ID_PCM_S16LE; av_init_packet(&c->audio_pkt[i]); c->audio_pkt[i].size = 0; c->audio_pkt[i].data = c->audio_buf[i]; c->audio_pkt[i].stream_index = c->ast[i]->index; c->audio_pkt[i].flags |= AV_PKT_FLAG_KEY; } c->ast[i]->codec->sample_rate = dv_audio_frequency[freq]; c->ast[i]->codec->channels = 2; c->ast[i]->codec->channel_layout = AV_CH_LAYOUT_STEREO; c->ast[i]->codec->bit_rate = 2 * dv_audio_frequency[freq] * 16; c->ast[i]->start_time = 0; } c->ach = i; return (c->sys->audio_min_samples[freq] + smpls) * 4; /* 2ch, 2bytes */; } static int dv_extract_video_info(DVDemuxContext *c, uint8_t* frame) { const uint8_t* vsc_pack; AVCodecContext* avctx; int apt, is16_9; int size = 0; if (c->sys) { avctx = c->vst->codec; avpriv_set_pts_info(c->vst, 64, c->sys->time_base.num, c->sys->time_base.den); avctx->time_base= c->sys->time_base; /* finding out SAR is a little bit messy */ vsc_pack = dv_extract_pack(frame, dv_video_control); apt = frame[4] & 0x07; is16_9 = (vsc_pack && ((vsc_pack[2] & 0x07) == 0x02 || (!apt && (vsc_pack[2] & 0x07) == 0x07))); c->vst->sample_aspect_ratio = c->sys->sar[is16_9]; avctx->bit_rate = av_rescale_q(c->sys->frame_size, (AVRational){8,1}, c->sys->time_base); size = c->sys->frame_size; } return size; } static int dv_extract_timecode(DVDemuxContext* c, uint8_t* frame, char *tc) { const uint8_t *tc_pack; // For PAL systems, drop frame bit is replaced by an arbitrary // bit so its value should not be considered. Drop frame timecode // is only relevant for NTSC systems. int prevent_df = c->sys->ltc_divisor == 25 || c->sys->ltc_divisor == 50; tc_pack = dv_extract_pack(frame, dv_timecode); if (!tc_pack) return 0; av_timecode_make_smpte_tc_string(tc, AV_RB32(tc_pack + 1), prevent_df); return 1; } /* * The following 3 functions constitute our interface to the world */ DVDemuxContext* avpriv_dv_init_demux(AVFormatContext *s) { DVDemuxContext *c; c = av_mallocz(sizeof(DVDemuxContext)); if (!c) return NULL; c->vst = avformat_new_stream(s, NULL); if (!c->vst) { av_free(c); return NULL; } c->fctx = s; c->vst->codec->codec_type = AVMEDIA_TYPE_VIDEO; c->vst->codec->codec_id = AV_CODEC_ID_DVVIDEO; c->vst->codec->bit_rate = 25000000; c->vst->start_time = 0; return c; } int avpriv_dv_get_packet(DVDemuxContext *c, AVPacket *pkt) { int size = -1; int i; for (i = 0; i < c->ach; i++) { if (c->ast[i] && c->audio_pkt[i].size) { *pkt = c->audio_pkt[i]; c->audio_pkt[i].size = 0; size = pkt->size; break; } } return size; } int avpriv_dv_produce_packet(DVDemuxContext *c, AVPacket *pkt, uint8_t* buf, int buf_size, int64_t pos) { int size, i; uint8_t *ppcm[4] = {0}; if (buf_size < DV_PROFILE_BYTES || !(c->sys = avpriv_dv_frame_profile(c->sys, buf, buf_size)) || buf_size < c->sys->frame_size) { return -1; /* Broken frame, or not enough data */ } /* Queueing audio packet */ /* FIXME: in case of no audio/bad audio we have to do something */ size = dv_extract_audio_info(c, buf); for (i = 0; i < c->ach; i++) { c->audio_pkt[i].pos = pos; c->audio_pkt[i].size = size; c->audio_pkt[i].pts = c->abytes * 30000 * 8 / c->ast[i]->codec->bit_rate; ppcm[i] = c->audio_buf[i]; } if (c->ach) dv_extract_audio(buf, ppcm, c->sys); /* We work with 720p frames split in half, thus even frames have * channels 0,1 and odd 2,3. */ if (c->sys->height == 720) { if (buf[1] & 0x0C) { c->audio_pkt[2].size = c->audio_pkt[3].size = 0; } else { c->audio_pkt[0].size = c->audio_pkt[1].size = 0; c->abytes += size; } } else { c->abytes += size; } /* Now it's time to return video packet */ size = dv_extract_video_info(c, buf); av_init_packet(pkt); pkt->data = buf; pkt->pos = pos; pkt->size = size; pkt->flags |= AV_PKT_FLAG_KEY; pkt->stream_index = c->vst->index; pkt->pts = c->frames; c->frames++; return size; } static int64_t dv_frame_offset(AVFormatContext *s, DVDemuxContext *c, int64_t timestamp, int flags) { // FIXME: sys may be wrong if last dv_read_packet() failed (buffer is junk) const DVprofile* sys = avpriv_dv_codec_profile(c->vst->codec); int64_t offset; int64_t size = avio_size(s->pb) - s->data_offset; int64_t max_offset = ((size-1) / sys->frame_size) * sys->frame_size; offset = sys->frame_size * timestamp; if (size >= 0 && offset > max_offset) offset = max_offset; else if (offset < 0) offset = 0; return offset + s->data_offset; } void ff_dv_offset_reset(DVDemuxContext *c, int64_t frame_offset) { c->frames= frame_offset; if (c->ach) { if (c->sys) { c->abytes= av_rescale_q(c->frames, c->sys->time_base, (AVRational){8, c->ast[0]->codec->bit_rate}); }else av_log(c->fctx, AV_LOG_ERROR, "cannot adjust audio bytes\n"); } c->audio_pkt[0].size = c->audio_pkt[1].size = 0; c->audio_pkt[2].size = c->audio_pkt[3].size = 0; } /************************************************************ * Implementation of the easiest DV storage of all -- raw DV. ************************************************************/ typedef struct RawDVContext { DVDemuxContext* dv_demux; uint8_t buf[DV_MAX_FRAME_SIZE]; } RawDVContext; static int dv_read_timecode(AVFormatContext *s) { int ret; char timecode[AV_TIMECODE_STR_SIZE]; int64_t pos = avio_tell(s->pb); // Read 3 DIF blocks: Header block and 2 Subcode blocks. int partial_frame_size = 3 * 80; uint8_t *partial_frame = av_mallocz(sizeof(*partial_frame) * partial_frame_size); RawDVContext *c = s->priv_data; ret = avio_read(s->pb, partial_frame, partial_frame_size); if (ret < 0) goto finish; if (ret < partial_frame_size) { ret = -1; goto finish; } ret = dv_extract_timecode(c->dv_demux, partial_frame, timecode); if (ret) av_dict_set(&s->metadata, "timecode", timecode, 0); else av_log(s, AV_LOG_ERROR, "Detected timecode is invalid\n"); finish: av_free(partial_frame); avio_seek(s->pb, pos, SEEK_SET); return ret; } static int dv_read_header(AVFormatContext *s) { unsigned state, marker_pos = 0; RawDVContext *c = s->priv_data; c->dv_demux = avpriv_dv_init_demux(s); if (!c->dv_demux) return -1; state = avio_rb32(s->pb); while ((state & 0xffffff7f) != 0x1f07003f) { if (url_feof(s->pb)) { av_log(s, AV_LOG_ERROR, "Cannot find DV header.\n"); return -1; } if (state == 0x003f0700 || state == 0xff3f0700) marker_pos = avio_tell(s->pb); if (state == 0xff3f0701 && avio_tell(s->pb) - marker_pos == 80) { avio_seek(s->pb, -163, SEEK_CUR); state = avio_rb32(s->pb); break; } state = (state << 8) | avio_r8(s->pb); } AV_WB32(c->buf, state); if (avio_read(s->pb, c->buf + 4, DV_PROFILE_BYTES - 4) != DV_PROFILE_BYTES - 4 || avio_seek(s->pb, -DV_PROFILE_BYTES, SEEK_CUR) < 0) return AVERROR(EIO); c->dv_demux->sys = avpriv_dv_frame_profile(c->dv_demux->sys, c->buf, DV_PROFILE_BYTES); if (!c->dv_demux->sys) { av_log(s, AV_LOG_ERROR, "Can't determine profile of DV input stream.\n"); return -1; } s->bit_rate = av_rescale_q(c->dv_demux->sys->frame_size, (AVRational){8,1}, c->dv_demux->sys->time_base); if (s->pb->seekable) dv_read_timecode(s); return 0; } static int dv_read_packet(AVFormatContext *s, AVPacket *pkt) { int size; RawDVContext *c = s->priv_data; size = avpriv_dv_get_packet(c->dv_demux, pkt); if (size < 0) { int64_t pos = avio_tell(s->pb); if (!c->dv_demux->sys) return AVERROR(EIO); size = c->dv_demux->sys->frame_size; if (avio_read(s->pb, c->buf, size) <= 0) return AVERROR(EIO); size = avpriv_dv_produce_packet(c->dv_demux, pkt, c->buf, size, pos); } return size; } static int dv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) { RawDVContext *r = s->priv_data; DVDemuxContext *c = r->dv_demux; int64_t offset = dv_frame_offset(s, c, timestamp, flags); if (avio_seek(s->pb, offset, SEEK_SET) < 0) return -1; ff_dv_offset_reset(c, offset / c->sys->frame_size); return 0; } static int dv_read_close(AVFormatContext *s) { RawDVContext *c = s->priv_data; av_free(c->dv_demux); return 0; } static int dv_probe(AVProbeData *p) { unsigned state, marker_pos = 0; int i; int matches = 0; int secondary_matches = 0; if (p->buf_size < 5) return 0; state = AV_RB32(p->buf); for (i = 4; i < p->buf_size; i++) { if ((state & 0xffffff7f) == 0x1f07003f) matches++; // any section header, also with seq/chan num != 0, // should appear around every 12000 bytes, at least 10 per frame if ((state & 0xff07ff7f) == 0x1f07003f) secondary_matches++; if (state == 0x003f0700 || state == 0xff3f0700) marker_pos = i; if (state == 0xff3f0701 && i - marker_pos == 80) matches++; state = (state << 8) | p->buf[i]; } if (matches && p->buf_size / matches < 1024*1024) { if (matches > 4 || (secondary_matches >= 10 && p->buf_size / secondary_matches < 24000)) return AVPROBE_SCORE_MAX*3/4; // not max to avoid dv in mov to match return AVPROBE_SCORE_MAX/4; } return 0; } #if CONFIG_DV_DEMUXER AVInputFormat ff_dv_demuxer = { .name = "dv", .long_name = NULL_IF_CONFIG_SMALL("DV (Digital Video)"), .priv_data_size = sizeof(RawDVContext), .read_probe = dv_probe, .read_header = dv_read_header, .read_packet = dv_read_packet, .read_close = dv_read_close, .read_seek = dv_read_seek, .extensions = "dv,dif", }; #endif