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/*
* DXA demuxer
* Copyright (c) 2007 Konstantin Shishkov
*
* 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/intreadwrite.h"
#include "avformat.h"
#include "riff.h"
#define DXA_EXTRA_SIZE 9
typedef struct{
int frames;
int has_sound;
int bpc;
uint32_t bytes_left;
int64_t wavpos, vidpos;
int readvid;
}DXAContext;
static int dxa_probe(AVProbeData *p)
{
int w, h;
if (p->buf_size < 15)
return 0;
w = AV_RB16(p->buf + 11);
h = AV_RB16(p->buf + 13);
/* check file header */
if (p->buf[0] == 'D' && p->buf[1] == 'E' &&
p->buf[2] == 'X' && p->buf[3] == 'A' &&
w && w <= 2048 && h && h <= 2048)
return AVPROBE_SCORE_MAX;
else
return 0;
}
static int dxa_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
AVIOContext *pb = s->pb;
DXAContext *c = s->priv_data;
AVStream *st, *ast;
uint32_t tag;
int32_t fps;
int w, h;
int num, den;
int flags;
tag = avio_rl32(pb);
if (tag != MKTAG('D', 'E', 'X', 'A'))
return -1;
flags = avio_r8(pb);
c->frames = avio_rb16(pb);
if(!c->frames){
av_log(s, AV_LOG_ERROR, "File contains no frames ???\n");
return -1;
}
fps = avio_rb32(pb);
if(fps > 0){
den = 1000;
num = fps;
}else if (fps < 0){
den = 100000;
num = -fps;
}else{
den = 10;
num = 1;
}
w = avio_rb16(pb);
h = avio_rb16(pb);
c->has_sound = 0;
st = av_new_stream(s, 0);
if (!st)
return -1;
// Parse WAV data header
if(avio_rl32(pb) == MKTAG('W', 'A', 'V', 'E')){
uint32_t size, fsize;
c->has_sound = 1;
size = avio_rb32(pb);
c->vidpos = avio_tell(pb) + size;
avio_skip(pb, 16);
fsize = avio_rl32(pb);
ast = av_new_stream(s, 0);
if (!ast)
return -1;
ff_get_wav_header(pb, ast->codec, fsize);
// find 'data' chunk
while(avio_tell(pb) < c->vidpos && !pb->eof_reached){
tag = avio_rl32(pb);
fsize = avio_rl32(pb);
if(tag == MKTAG('d', 'a', 't', 'a')) break;
avio_skip(pb, fsize);
}
c->bpc = (fsize + c->frames - 1) / c->frames;
if(ast->codec->block_align)
c->bpc = ((c->bpc + ast->codec->block_align - 1) / ast->codec->block_align) * ast->codec->block_align;
c->bytes_left = fsize;
c->wavpos = avio_tell(pb);
avio_seek(pb, c->vidpos, SEEK_SET);
}
/* now we are ready: build format streams */
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_id = CODEC_ID_DXA;
st->codec->width = w;
st->codec->height = h;
av_reduce(&den, &num, den, num, (1UL<<31)-1);
av_set_pts_info(st, 33, num, den);
/* flags & 0x80 means that image is interlaced,
* flags & 0x40 means that image has double height
* either way set true height
*/
if(flags & 0xC0){
st->codec->height >>= 1;
}
c->readvid = !c->has_sound;
c->vidpos = avio_tell(pb);
s->start_time = 0;
s->duration = (int64_t)c->frames * AV_TIME_BASE * num / den;
av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames);
return 0;
}
static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt)
{
DXAContext *c = s->priv_data;
int ret;
uint32_t size;
uint8_t buf[DXA_EXTRA_SIZE], pal[768+4];
int pal_size = 0;
if(!c->readvid && c->has_sound && c->bytes_left){
c->readvid = 1;
avio_seek(s->pb, c->wavpos, SEEK_SET);
size = FFMIN(c->bytes_left, c->bpc);
ret = av_get_packet(s->pb, pkt, size);
pkt->stream_index = 1;
if(ret != size)
return AVERROR(EIO);
c->bytes_left -= size;
c->wavpos = avio_tell(s->pb);
return 0;
}
avio_seek(s->pb, c->vidpos, SEEK_SET);
while(!s->pb->eof_reached && c->frames){
avio_read(s->pb, buf, 4);
switch(AV_RL32(buf)){
case MKTAG('N', 'U', 'L', 'L'):
if(av_new_packet(pkt, 4 + pal_size) < 0)
return AVERROR(ENOMEM);
pkt->stream_index = 0;
if(pal_size) memcpy(pkt->data, pal, pal_size);
memcpy(pkt->data + pal_size, buf, 4);
c->frames--;
c->vidpos = avio_tell(s->pb);
c->readvid = 0;
return 0;
case MKTAG('C', 'M', 'A', 'P'):
pal_size = 768+4;
memcpy(pal, buf, 4);
avio_read(s->pb, pal + 4, 768);
break;
case MKTAG('F', 'R', 'A', 'M'):
avio_read(s->pb, buf + 4, DXA_EXTRA_SIZE - 4);
size = AV_RB32(buf + 5);
if(size > 0xFFFFFF){
av_log(s, AV_LOG_ERROR, "Frame size is too big: %d\n", size);
return -1;
}
if(av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size) < 0)
return AVERROR(ENOMEM);
memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE);
ret = avio_read(s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size);
if(ret != size){
av_free_packet(pkt);
return AVERROR(EIO);
}
if(pal_size) memcpy(pkt->data, pal, pal_size);
pkt->stream_index = 0;
c->frames--;
c->vidpos = avio_tell(s->pb);
c->readvid = 0;
return 0;
default:
av_log(s, AV_LOG_ERROR, "Unknown tag %c%c%c%c\n", buf[0], buf[1], buf[2], buf[3]);
return -1;
}
}
return AVERROR(EIO);
}
AVInputFormat ff_dxa_demuxer = {
"dxa",
NULL_IF_CONFIG_SMALL("DXA"),
sizeof(DXAContext),
dxa_probe,
dxa_read_header,
dxa_read_packet,
};
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