ffmpeg/libavformat/hnm.c

170 lines
4.7 KiB
C

/*
* Cryo Interactive Entertainment HNM4 demuxer
*
* Copyright (c) 2012 David Kment
*
* 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 <inttypes.h>
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#define HNM4_TAG MKTAG('H', 'N', 'M', '4')
#define HNM4_SAMPLE_RATE 22050
#define HNM4_FRAME_FPS 24
#define HNM4_CHUNK_ID_PL 19536
#define HNM4_CHUNK_ID_IZ 23113
#define HNM4_CHUNK_ID_IU 21833
#define HNM4_CHUNK_ID_SD 17491
typedef struct Hnm4DemuxContext {
uint32_t frames;
uint32_t currentframe;
uint32_t superchunk_remaining;
} Hnm4DemuxContext;
static int hnm_probe(const AVProbeData *p)
{
if (p->buf_size < 4)
return 0;
// check for HNM4 header.
// currently only HNM v4/v4A is supported
if (AV_RL32(&p->buf[0]) == HNM4_TAG)
return AVPROBE_SCORE_MAX;
return 0;
}
static int hnm_read_header(AVFormatContext *s)
{
Hnm4DemuxContext *hnm = s->priv_data;
AVIOContext *pb = s->pb;
unsigned width, height;
AVStream *vst;
int ret;
avio_skip(pb, 8);
width = avio_rl16(pb);
height = avio_rl16(pb);
avio_rl32(pb); // filesize
hnm->frames = avio_rl32(pb);
avio_skip(pb, 44);
if (width < 256 || width > 640 ||
height < 150 || height > 480) {
av_log(s, AV_LOG_ERROR,
"invalid resolution: %ux%u\n", width, height);
return AVERROR_INVALIDDATA;
}
if (!(vst = avformat_new_stream(s, NULL)))
return AVERROR(ENOMEM);
vst->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
vst->codecpar->codec_id = AV_CODEC_ID_HNM4_VIDEO;
vst->codecpar->codec_tag = 0;
vst->codecpar->width = width;
vst->codecpar->height = height;
if ((ret = ff_alloc_extradata(vst->codecpar, 1)) < 0)
return ret;
// TODO: find a better way to detect HNM4A
vst->codecpar->extradata[0] = width == 640 ? 0x4a : 0x40;
vst->start_time = 0;
avpriv_set_pts_info(vst, 33, 1, HNM4_FRAME_FPS);
return 0;
}
static int hnm_read_packet(AVFormatContext *s, AVPacket *pkt)
{
Hnm4DemuxContext *hnm = s->priv_data;
AVIOContext *pb = s->pb;
int ret = 0;
uint32_t superchunk_size, chunk_size;
uint16_t chunk_id;
if (hnm->currentframe == hnm->frames || pb->eof_reached)
return AVERROR_EOF;
if (hnm->superchunk_remaining == 0) {
/* parse next superchunk */
superchunk_size = avio_rl24(pb);
avio_skip(pb, 1);
hnm->superchunk_remaining = superchunk_size - 4;
}
chunk_size = avio_rl24(pb);
avio_skip(pb, 1);
chunk_id = avio_rl16(pb);
avio_skip(pb, 2);
if (chunk_size > hnm->superchunk_remaining || !chunk_size) {
av_log(s, AV_LOG_ERROR,
"invalid chunk size: %"PRIu32", offset: %"PRId64"\n",
chunk_size, avio_tell(pb));
avio_skip(pb, hnm->superchunk_remaining - 8);
hnm->superchunk_remaining = 0;
}
switch (chunk_id) {
case HNM4_CHUNK_ID_PL:
case HNM4_CHUNK_ID_IZ:
case HNM4_CHUNK_ID_IU:
avio_seek(pb, -8, SEEK_CUR);
ret += av_get_packet(pb, pkt, chunk_size);
hnm->superchunk_remaining -= chunk_size;
if (chunk_id == HNM4_CHUNK_ID_IZ || chunk_id == HNM4_CHUNK_ID_IU)
hnm->currentframe++;
break;
case HNM4_CHUNK_ID_SD:
avio_skip(pb, chunk_size - 8);
hnm->superchunk_remaining -= chunk_size;
break;
default:
av_log(s, AV_LOG_WARNING, "unknown chunk found: %"PRIu16", offset: %"PRId64"\n",
chunk_id, avio_tell(pb));
avio_skip(pb, chunk_size - 8);
hnm->superchunk_remaining -= chunk_size;
break;
}
return ret;
}
AVInputFormat ff_hnm_demuxer = {
.name = "hnm",
.long_name = NULL_IF_CONFIG_SMALL("Cryo HNM v4"),
.priv_data_size = sizeof(Hnm4DemuxContext),
.read_probe = hnm_probe,
.read_header = hnm_read_header,
.read_packet = hnm_read_packet,
.flags = AVFMT_NO_BYTE_SEEK | AVFMT_NOGENSEARCH | AVFMT_NOBINSEARCH
};