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/*
* CDXL demuxer
* Copyright (c) 2011-2012 Paul B Mahol
*
* 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/channel_layout.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/parseutils.h"
#include "libavutil/opt.h"
#include "avformat.h"
#include "internal.h"
#define CDXL_HEADER_SIZE 32
typedef struct CDXLDemuxContext {
AVClass *class;
int sample_rate;
char *framerate;
AVRational fps;
int read_chunk;
uint8_t header[CDXL_HEADER_SIZE];
int video_stream_index;
int audio_stream_index;
} CDXLDemuxContext;
static int cdxl_read_probe(AVProbeData *p)
{
int score = AVPROBE_SCORE_MAX / 2 + 10;
if (p->buf_size < CDXL_HEADER_SIZE)
return 0;
/* reserved bytes should always be set to 0 */
if (AV_RN64(&p->buf[24]) || AV_RN16(&p->buf[10]))
return 0;
/* check type */
if (p->buf[0] != 1)
return 0;
/* check palette size */
if (AV_RB16(&p->buf[20]) > 512)
return 0;
/* check number of planes */
if (p->buf[18] || !p->buf[19])
return 0;
/* check widh and height */
if (!AV_RN16(&p->buf[14]) || !AV_RN16(&p->buf[16]))
return 0;
/* chunk size */
if (AV_RB32(&p->buf[2]) < AV_RB16(&p->buf[22]) + AV_RB16(&p->buf[20]) + CDXL_HEADER_SIZE)
return 0;
/* previous chunk size */
if (AV_RN32(&p->buf[6]))
score /= 2;
/* current frame number, usually starts from 1 */
if (AV_RB16(&p->buf[12]) != 1)
score /= 2;
return score;
}
static int cdxl_read_header(AVFormatContext *s)
{
CDXLDemuxContext *cdxl = s->priv_data;
int ret;
if (cdxl->framerate && (ret = av_parse_video_rate(&cdxl->fps, cdxl->framerate)) < 0) {
av_log(s, AV_LOG_ERROR,
"Could not parse framerate: %s.\n", cdxl->framerate);
return ret;
}
cdxl->read_chunk = 0;
cdxl->video_stream_index = -1;
cdxl->audio_stream_index = -1;
s->ctx_flags |= AVFMTCTX_NOHEADER;
return 0;
}
static int cdxl_read_packet(AVFormatContext *s, AVPacket *pkt)
{
CDXLDemuxContext *cdxl = s->priv_data;
AVIOContext *pb = s->pb;
uint32_t current_size, video_size, image_size;
uint16_t audio_size, palette_size, width, height;
int64_t pos;
int ret;
if (url_feof(pb))
return AVERROR_EOF;
pos = avio_tell(pb);
if (!cdxl->read_chunk &&
avio_read(pb, cdxl->header, CDXL_HEADER_SIZE) != CDXL_HEADER_SIZE)
return AVERROR_EOF;
if (cdxl->header[0] != 1) {
av_log(s, AV_LOG_ERROR, "non-standard cdxl file\n");
return AVERROR_INVALIDDATA;
}
current_size = AV_RB32(&cdxl->header[2]);
width = AV_RB16(&cdxl->header[14]);
height = AV_RB16(&cdxl->header[16]);
palette_size = AV_RB16(&cdxl->header[20]);
audio_size = AV_RB16(&cdxl->header[22]);
image_size = FFALIGN(width, 16) * height * cdxl->header[19] / 8;
video_size = palette_size + image_size;
if (palette_size > 512)
return AVERROR_INVALIDDATA;
if (current_size < (uint64_t)audio_size + video_size + CDXL_HEADER_SIZE)
return AVERROR_INVALIDDATA;
if (cdxl->read_chunk && audio_size) {
if (cdxl->audio_stream_index == -1) {
AVStream *st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
st->codec->codec_tag = 0;
st->codec->codec_id = AV_CODEC_ID_PCM_S8;
if (cdxl->header[1] & 0x10) {
st->codec->channels = 2;
st->codec->channel_layout = AV_CH_LAYOUT_STEREO;
} else {
st->codec->channels = 1;
st->codec->channel_layout = AV_CH_LAYOUT_MONO;
}
st->codec->sample_rate = cdxl->sample_rate;
st->start_time = 0;
cdxl->audio_stream_index = st->index;
avpriv_set_pts_info(st, 64, 1, cdxl->sample_rate);
}
ret = av_get_packet(pb, pkt, audio_size);
if (ret < 0)
return ret;
pkt->stream_index = cdxl->audio_stream_index;
pkt->pos = pos;
pkt->duration = audio_size;
cdxl->read_chunk = 0;
} else {
if (cdxl->video_stream_index == -1) {
AVStream *st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_tag = 0;
st->codec->codec_id = AV_CODEC_ID_CDXL;
st->codec->width = width;
st->codec->height = height;
st->start_time = 0;
cdxl->video_stream_index = st->index;
if (cdxl->framerate)
avpriv_set_pts_info(st, 64, cdxl->fps.den, cdxl->fps.num);
else
avpriv_set_pts_info(st, 64, 1, cdxl->sample_rate);
}
if (av_new_packet(pkt, video_size + CDXL_HEADER_SIZE) < 0)
return AVERROR(ENOMEM);
memcpy(pkt->data, cdxl->header, CDXL_HEADER_SIZE);
ret = avio_read(pb, pkt->data + CDXL_HEADER_SIZE, video_size);
if (ret < 0) {
av_free_packet(pkt);
return ret;
}
av_shrink_packet(pkt, CDXL_HEADER_SIZE + ret);
pkt->stream_index = cdxl->video_stream_index;
pkt->flags |= AV_PKT_FLAG_KEY;
pkt->pos = pos;
pkt->duration = cdxl->framerate ? 1 : audio_size ? audio_size : 220;
cdxl->read_chunk = audio_size;
}
if (!cdxl->read_chunk)
avio_skip(pb, current_size - audio_size - video_size - CDXL_HEADER_SIZE);
return ret;
}
#define OFFSET(x) offsetof(CDXLDemuxContext, x)
static const AVOption cdxl_options[] = {
{ "sample_rate", "", OFFSET(sample_rate), AV_OPT_TYPE_INT, { .i64 = 11025 }, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
{ "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, AV_OPT_FLAG_DECODING_PARAM },
{ NULL },
};
static const AVClass cdxl_demuxer_class = {
.class_name = "CDXL demuxer",
.item_name = av_default_item_name,
.option = cdxl_options,
.version = LIBAVUTIL_VERSION_INT,
};
AVInputFormat ff_cdxl_demuxer = {
.name = "cdxl",
.long_name = NULL_IF_CONFIG_SMALL("Commodore CDXL video"),
.priv_data_size = sizeof(CDXLDemuxContext),
.read_probe = cdxl_read_probe,
.read_header = cdxl_read_header,
.read_packet = cdxl_read_packet,
.extensions = "cdxl,xl",
.flags = AVFMT_GENERIC_INDEX,
.priv_class = &cdxl_demuxer_class,
};
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