forked from KolibriOS/kolibrios
ecf3e862ea
git-svn-id: svn://kolibrios.org@6148 a494cfbc-eb01-0410-851d-a64ba20cac60
632 lines
20 KiB
C
632 lines
20 KiB
C
/*
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* General DV muxer/demuxer
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* Copyright (c) 2003 Roman Shaposhnik
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*
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* Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth
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* of DV technical info.
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*
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* Raw DV format
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* Copyright (c) 2002 Fabrice Bellard
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*
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* 50 Mbps (DVCPRO50) and 100 Mbps (DVCPRO HD) support
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* Copyright (c) 2006 Daniel Maas <dmaas@maasdigital.com>
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* Funded by BBC Research & Development
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include <time.h>
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#include "avformat.h"
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#include "internal.h"
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#include "libavcodec/dv_profile.h"
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#include "libavcodec/dvdata.h"
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#include "libavutil/channel_layout.h"
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#include "libavutil/intreadwrite.h"
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#include "libavutil/mathematics.h"
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#include "libavutil/timecode.h"
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#include "dv.h"
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#include "libavutil/avassert.h"
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struct DVDemuxContext {
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const DVprofile* sys; /* Current DV profile. E.g.: 525/60, 625/50 */
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AVFormatContext* fctx;
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AVStream* vst;
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AVStream* ast[4];
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AVPacket audio_pkt[4];
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uint8_t audio_buf[4][8192];
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int ach;
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int frames;
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uint64_t abytes;
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};
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static inline uint16_t dv_audio_12to16(uint16_t sample)
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{
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uint16_t shift, result;
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sample = (sample < 0x800) ? sample : sample | 0xf000;
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shift = (sample & 0xf00) >> 8;
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if (shift < 0x2 || shift > 0xd) {
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result = sample;
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} else if (shift < 0x8) {
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shift--;
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result = (sample - (256 * shift)) << shift;
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} else {
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shift = 0xe - shift;
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result = ((sample + ((256 * shift) + 1)) << shift) - 1;
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}
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return result;
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}
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/*
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* This is the dumbest implementation of all -- it simply looks at
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* a fixed offset and if pack isn't there -- fails. We might want
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* to have a fallback mechanism for complete search of missing packs.
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*/
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static const uint8_t *dv_extract_pack(uint8_t *frame, enum dv_pack_type t)
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{
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int offs;
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switch (t) {
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case dv_audio_source:
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offs = (80 * 6 + 80 * 16 * 3 + 3);
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break;
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case dv_audio_control:
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offs = (80 * 6 + 80 * 16 * 4 + 3);
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break;
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case dv_video_control:
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offs = (80 * 5 + 48 + 5);
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break;
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case dv_timecode:
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offs = (80*1 + 3 + 3);
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break;
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default:
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return NULL;
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}
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return frame[offs] == t ? &frame[offs] : NULL;
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}
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static const int dv_audio_frequency[3] = {
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48000, 44100, 32000,
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};
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/*
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* There's a couple of assumptions being made here:
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* 1. By default we silence erroneous (0x8000/16bit 0x800/12bit) audio samples.
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* We can pass them upwards when libavcodec will be ready to deal with them.
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* 2. We don't do software emphasis.
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* 3. Audio is always returned as 16bit linear samples: 12bit nonlinear samples
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* are converted into 16bit linear ones.
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*/
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static int dv_extract_audio(uint8_t *frame, uint8_t **ppcm,
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const DVprofile *sys)
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{
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int size, chan, i, j, d, of, smpls, freq, quant, half_ch;
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uint16_t lc, rc;
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const uint8_t *as_pack;
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uint8_t *pcm, ipcm;
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as_pack = dv_extract_pack(frame, dv_audio_source);
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if (!as_pack) /* No audio ? */
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return 0;
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smpls = as_pack[1] & 0x3f; /* samples in this frame - min. samples */
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freq = as_pack[4] >> 3 & 0x07; /* 0 - 48kHz, 1 - 44,1kHz, 2 - 32kHz */
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quant = as_pack[4] & 0x07; /* 0 - 16bit linear, 1 - 12bit nonlinear */
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if (quant > 1)
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return -1; /* unsupported quantization */
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if (freq >= FF_ARRAY_ELEMS(dv_audio_frequency))
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return AVERROR_INVALIDDATA;
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size = (sys->audio_min_samples[freq] + smpls) * 4; /* 2ch, 2bytes */
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half_ch = sys->difseg_size / 2;
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/* We work with 720p frames split in half, thus even frames have
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* channels 0,1 and odd 2,3. */
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ipcm = (sys->height == 720 && !(frame[1] & 0x0C)) ? 2 : 0;
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if (ipcm + sys->n_difchan > (quant == 1 ? 2 : 4)) {
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av_log(NULL, AV_LOG_ERROR, "too many dv pcm frames\n");
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return AVERROR_INVALIDDATA;
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}
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/* for each DIF channel */
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for (chan = 0; chan < sys->n_difchan; chan++) {
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av_assert0(ipcm<4);
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pcm = ppcm[ipcm++];
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if (!pcm)
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break;
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/* for each DIF segment */
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for (i = 0; i < sys->difseg_size; i++) {
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frame += 6 * 80; /* skip DIF segment header */
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if (quant == 1 && i == half_ch) {
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/* next stereo channel (12bit mode only) */
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av_assert0(ipcm<4);
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pcm = ppcm[ipcm++];
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if (!pcm)
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break;
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}
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/* for each AV sequence */
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for (j = 0; j < 9; j++) {
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for (d = 8; d < 80; d += 2) {
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if (quant == 0) { /* 16bit quantization */
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of = sys->audio_shuffle[i][j] +
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(d - 8) / 2 * sys->audio_stride;
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if (of * 2 >= size)
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continue;
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/* FIXME: maybe we have to admit that DV is a
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* big-endian PCM */
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pcm[of * 2] = frame[d + 1];
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pcm[of * 2 + 1] = frame[d];
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if (pcm[of * 2 + 1] == 0x80 && pcm[of * 2] == 0x00)
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pcm[of * 2 + 1] = 0;
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} else { /* 12bit quantization */
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lc = ((uint16_t)frame[d] << 4) |
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((uint16_t)frame[d + 2] >> 4);
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rc = ((uint16_t)frame[d + 1] << 4) |
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((uint16_t)frame[d + 2] & 0x0f);
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lc = (lc == 0x800 ? 0 : dv_audio_12to16(lc));
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rc = (rc == 0x800 ? 0 : dv_audio_12to16(rc));
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of = sys->audio_shuffle[i % half_ch][j] +
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(d - 8) / 3 * sys->audio_stride;
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if (of * 2 >= size)
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continue;
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/* FIXME: maybe we have to admit that DV is a
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* big-endian PCM */
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pcm[of * 2] = lc & 0xff;
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pcm[of * 2 + 1] = lc >> 8;
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of = sys->audio_shuffle[i % half_ch + half_ch][j] +
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(d - 8) / 3 * sys->audio_stride;
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/* FIXME: maybe we have to admit that DV is a
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* big-endian PCM */
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pcm[of * 2] = rc & 0xff;
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pcm[of * 2 + 1] = rc >> 8;
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++d;
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}
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}
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frame += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */
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}
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}
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}
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return size;
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}
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static int dv_extract_audio_info(DVDemuxContext *c, uint8_t *frame)
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{
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const uint8_t *as_pack;
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int freq, stype, smpls, quant, i, ach;
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as_pack = dv_extract_pack(frame, dv_audio_source);
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if (!as_pack || !c->sys) { /* No audio ? */
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c->ach = 0;
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return 0;
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}
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smpls = as_pack[1] & 0x3f; /* samples in this frame - min. samples */
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freq = as_pack[4] >> 3 & 0x07; /* 0 - 48kHz, 1 - 44,1kHz, 2 - 32kHz */
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stype = as_pack[3] & 0x1f; /* 0 - 2CH, 2 - 4CH, 3 - 8CH */
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quant = as_pack[4] & 0x07; /* 0 - 16bit linear, 1 - 12bit nonlinear */
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if (freq >= FF_ARRAY_ELEMS(dv_audio_frequency)) {
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av_log(c->fctx, AV_LOG_ERROR,
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"Unrecognized audio sample rate index (%d)\n", freq);
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return 0;
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}
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if (stype > 3) {
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av_log(c->fctx, AV_LOG_ERROR, "stype %d is invalid\n", stype);
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c->ach = 0;
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return 0;
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}
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/* note: ach counts PAIRS of channels (i.e. stereo channels) */
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ach = ((int[4]) { 1, 0, 2, 4 })[stype];
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if (ach == 1 && quant && freq == 2)
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ach = 2;
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/* Dynamic handling of the audio streams in DV */
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for (i = 0; i < ach; i++) {
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if (!c->ast[i]) {
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c->ast[i] = avformat_new_stream(c->fctx, NULL);
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if (!c->ast[i])
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break;
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avpriv_set_pts_info(c->ast[i], 64, 1, 30000);
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c->ast[i]->codec->codec_type = AVMEDIA_TYPE_AUDIO;
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c->ast[i]->codec->codec_id = AV_CODEC_ID_PCM_S16LE;
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av_init_packet(&c->audio_pkt[i]);
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c->audio_pkt[i].size = 0;
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c->audio_pkt[i].data = c->audio_buf[i];
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c->audio_pkt[i].stream_index = c->ast[i]->index;
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c->audio_pkt[i].flags |= AV_PKT_FLAG_KEY;
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}
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c->ast[i]->codec->sample_rate = dv_audio_frequency[freq];
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c->ast[i]->codec->channels = 2;
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c->ast[i]->codec->channel_layout = AV_CH_LAYOUT_STEREO;
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c->ast[i]->codec->bit_rate = 2 * dv_audio_frequency[freq] * 16;
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c->ast[i]->start_time = 0;
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}
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c->ach = i;
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return (c->sys->audio_min_samples[freq] + smpls) * 4; /* 2ch, 2bytes */
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}
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static int dv_extract_video_info(DVDemuxContext *c, uint8_t *frame)
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{
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const uint8_t *vsc_pack;
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AVCodecContext *avctx;
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int apt, is16_9;
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int size = 0;
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if (c->sys) {
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avctx = c->vst->codec;
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avpriv_set_pts_info(c->vst, 64, c->sys->time_base.num,
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c->sys->time_base.den);
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avctx->time_base = c->sys->time_base;
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/* finding out SAR is a little bit messy */
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vsc_pack = dv_extract_pack(frame, dv_video_control);
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apt = frame[4] & 0x07;
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is16_9 = (vsc_pack && ((vsc_pack[2] & 0x07) == 0x02 ||
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(!apt && (vsc_pack[2] & 0x07) == 0x07)));
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c->vst->sample_aspect_ratio = c->sys->sar[is16_9];
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avctx->bit_rate = av_rescale_q(c->sys->frame_size,
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(AVRational) { 8, 1 },
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c->sys->time_base);
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size = c->sys->frame_size;
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}
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return size;
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}
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static int dv_extract_timecode(DVDemuxContext* c, uint8_t* frame, char *tc)
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{
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const uint8_t *tc_pack;
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// For PAL systems, drop frame bit is replaced by an arbitrary
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// bit so its value should not be considered. Drop frame timecode
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// is only relevant for NTSC systems.
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int prevent_df = c->sys->ltc_divisor == 25 || c->sys->ltc_divisor == 50;
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tc_pack = dv_extract_pack(frame, dv_timecode);
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if (!tc_pack)
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return 0;
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av_timecode_make_smpte_tc_string(tc, AV_RB32(tc_pack + 1), prevent_df);
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return 1;
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}
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/* The following 3 functions constitute our interface to the world */
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DVDemuxContext *avpriv_dv_init_demux(AVFormatContext *s)
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{
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DVDemuxContext *c;
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c = av_mallocz(sizeof(DVDemuxContext));
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if (!c)
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return NULL;
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c->vst = avformat_new_stream(s, NULL);
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if (!c->vst) {
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av_free(c);
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return NULL;
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}
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c->fctx = s;
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c->vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
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c->vst->codec->codec_id = AV_CODEC_ID_DVVIDEO;
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c->vst->codec->bit_rate = 25000000;
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c->vst->start_time = 0;
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return c;
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}
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int avpriv_dv_get_packet(DVDemuxContext *c, AVPacket *pkt)
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{
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int size = -1;
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int i;
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for (i = 0; i < c->ach; i++) {
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if (c->ast[i] && c->audio_pkt[i].size) {
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*pkt = c->audio_pkt[i];
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c->audio_pkt[i].size = 0;
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size = pkt->size;
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break;
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}
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}
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return size;
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}
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int avpriv_dv_produce_packet(DVDemuxContext *c, AVPacket *pkt,
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uint8_t *buf, int buf_size, int64_t pos)
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{
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int size, i;
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uint8_t *ppcm[5] = { 0 };
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if (buf_size < DV_PROFILE_BYTES ||
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!(c->sys = avpriv_dv_frame_profile(c->sys, buf, buf_size)) ||
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buf_size < c->sys->frame_size) {
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return -1; /* Broken frame, or not enough data */
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}
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/* Queueing audio packet */
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/* FIXME: in case of no audio/bad audio we have to do something */
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size = dv_extract_audio_info(c, buf);
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for (i = 0; i < c->ach; i++) {
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c->audio_pkt[i].pos = pos;
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c->audio_pkt[i].size = size;
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c->audio_pkt[i].pts = c->abytes * 30000 * 8 /
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c->ast[i]->codec->bit_rate;
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ppcm[i] = c->audio_buf[i];
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}
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if (c->ach)
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dv_extract_audio(buf, ppcm, c->sys);
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/* We work with 720p frames split in half, thus even frames have
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* channels 0,1 and odd 2,3. */
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if (c->sys->height == 720) {
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if (buf[1] & 0x0C) {
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c->audio_pkt[2].size = c->audio_pkt[3].size = 0;
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} else {
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c->audio_pkt[0].size = c->audio_pkt[1].size = 0;
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c->abytes += size;
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}
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} else {
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c->abytes += size;
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}
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/* Now it's time to return video packet */
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size = dv_extract_video_info(c, buf);
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av_init_packet(pkt);
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pkt->data = buf;
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pkt->pos = pos;
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pkt->size = size;
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pkt->flags |= AV_PKT_FLAG_KEY;
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pkt->stream_index = c->vst->index;
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pkt->pts = c->frames;
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c->frames++;
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return size;
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}
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static int64_t dv_frame_offset(AVFormatContext *s, DVDemuxContext *c,
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int64_t timestamp, int flags)
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{
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// FIXME: sys may be wrong if last dv_read_packet() failed (buffer is junk)
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const DVprofile *sys = avpriv_dv_codec_profile(c->vst->codec);
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int64_t offset;
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int64_t size = avio_size(s->pb) - s->data_offset;
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int64_t max_offset = ((size - 1) / sys->frame_size) * sys->frame_size;
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offset = sys->frame_size * timestamp;
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if (size >= 0 && offset > max_offset)
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offset = max_offset;
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else if (offset < 0)
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offset = 0;
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return offset + s->data_offset;
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}
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void ff_dv_offset_reset(DVDemuxContext *c, int64_t frame_offset)
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{
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c->frames = frame_offset;
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if (c->ach) {
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if (c->sys) {
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c->abytes = av_rescale_q(c->frames, c->sys->time_base,
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(AVRational) { 8, c->ast[0]->codec->bit_rate });
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} else
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av_log(c->fctx, AV_LOG_ERROR, "cannot adjust audio bytes\n");
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}
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c->audio_pkt[0].size = c->audio_pkt[1].size = 0;
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c->audio_pkt[2].size = c->audio_pkt[3].size = 0;
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}
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/************************************************************
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* Implementation of the easiest DV storage of all -- raw DV.
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************************************************************/
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typedef struct RawDVContext {
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DVDemuxContext *dv_demux;
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uint8_t buf[DV_MAX_FRAME_SIZE];
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} RawDVContext;
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static int dv_read_timecode(AVFormatContext *s) {
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int ret;
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char timecode[AV_TIMECODE_STR_SIZE];
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int64_t pos = avio_tell(s->pb);
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// Read 3 DIF blocks: Header block and 2 Subcode blocks.
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int partial_frame_size = 3 * 80;
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uint8_t *partial_frame = av_mallocz(sizeof(*partial_frame) *
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partial_frame_size);
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RawDVContext *c = s->priv_data;
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ret = avio_read(s->pb, partial_frame, partial_frame_size);
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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))
|
|
// not max to avoid dv in mov to match
|
|
return AVPROBE_SCORE_MAX * 3 / 4;
|
|
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
|