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FFmpeg/libavformat/dv.c
Diego Biurrun 3cbe112653 dv: Split DV data table declarations into their own header 
This is necessary to avoid target config settings bleeding into the host
compilation process with hardcoded tables and the DV VLC tables no longer
present as static tables in a header file.
2013-11-15 01:29:47 +01:00

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/*
* 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 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 <time.h>
#include "avformat.h"
#include "internal.h"
#include "libavcodec/dv_profile.h"
#include "libavcodec/dv.h"
#include "libavutil/channel_layout.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/mathematics.h"
#include "dv.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;
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,
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;
/* for each DIF channel */
for (chan = 0; chan < sys->n_difchan; chan++) {
/* next stereo channel (50Mbps and 100Mbps only) */
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) */
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;
/* FIXME: maybe we have to admit that DV is a
* big-endian PCM */
pcm[of * 2] = frame[d + 1];
pcm[of * 2 + 1] = frame[d];
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;
/* FIXME: maybe we have to admit that DV is a
* big-endian PCM */
pcm[of * 2] = lc & 0xff;
pcm[of * 2 + 1] = lc >> 8;
of = sys->audio_shuffle[i % half_ch + half_ch][j] +
(d - 8) / 3 * sys->audio_stride;
/* FIXME: maybe we have to admit that DV is a
* big-endian PCM */
pcm[of * 2] = rc & 0xff;
pcm[of * 2 + 1] = rc >> 8;
++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;
if (!avctx->width) {
avctx->width = c->sys->width;
avctx->height = c->sys->height;
}
avctx->pix_fmt = c->sys->pix_fmt;
/* 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;
}
/* 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)
{
int size, i;
uint8_t *ppcm[5] = { 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].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->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)
c->abytes = av_rescale_q(c->frames, c->sys->time_base,
(AVRational) { 8, c->ast[0]->codec->bit_rate });
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_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 (s->pb->eof_reached) {
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) <= 0 ||
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);
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) {
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);
}
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
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