ffmpeg/libavformat/ifv.c

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/*
* IFV demuxer
*
* Copyright (c) 2019 Swaraj Hota
*
* 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 "avformat.h"
#include "internal.h"
#include "avio_internal.h"
typedef struct IFVContext {
uint32_t next_video_index;
uint32_t next_audio_index;
uint32_t total_vframes;
uint32_t total_aframes;
int width, height;
int is_audio_present;
int sample_rate;
int video_stream_index;
int audio_stream_index;
} IFVContext;
static int ifv_probe(const AVProbeData *p)
{
static const uint8_t ifv_magic[] = {0x11, 0xd2, 0xd3, 0xab, 0xba, 0xa9,
0xcf, 0x11, 0x8e, 0xe6, 0x00, 0xc0, 0x0c, 0x20, 0x53, 0x65, 0x44};
if (!memcmp(p->buf, ifv_magic, sizeof(ifv_magic)))
return AVPROBE_SCORE_MAX;
return 0;
}
static int read_index(AVFormatContext *s,
enum AVMediaType frame_type,
uint32_t start_index)
{
IFVContext *ifv = s->priv_data;
AVStream *st;
int64_t pos, size, timestamp;
uint32_t end_index, i;
int ret;
if (frame_type == AVMEDIA_TYPE_VIDEO) {
end_index = ifv->total_vframes;
st = s->streams[ifv->video_stream_index];
} else {
end_index = ifv->total_aframes;
st = s->streams[ifv->audio_stream_index];
}
for (i = start_index; i < end_index; i++) {
if (avio_feof(s->pb))
return AVERROR_EOF;
pos = avio_rl32(s->pb);
size = avio_rl32(s->pb);
avio_skip(s->pb, 8);
timestamp = avio_rl32(s->pb);
ret = av_add_index_entry(st, pos, timestamp, size, 0, 0);
if (ret < 0)
return ret;
avio_skip(s->pb, frame_type == AVMEDIA_TYPE_VIDEO ? 8: 4);
}
return 0;
}
static int parse_header(AVFormatContext *s)
{
IFVContext *ifv = s->priv_data;
uint32_t aud_magic;
uint32_t vid_magic;
avio_skip(s->pb, 0x34);
avpriv_dict_set_timestamp(&s->metadata, "creation_time", avio_rl32(s->pb) * 1000000LL);
avio_skip(s->pb, 0x24);
ifv->width = avio_rl16(s->pb);
ifv->height = avio_rl16(s->pb);
avio_skip(s->pb, 0x8);
vid_magic = avio_rl32(s->pb);
if (vid_magic != MKTAG('H','2','6','4'))
avpriv_request_sample(s, "Unknown video codec %x", vid_magic);
avio_skip(s->pb, 0x2c);
ifv->sample_rate = avio_rl32(s->pb);
aud_magic = avio_rl32(s->pb);
if (aud_magic == MKTAG('G','R','A','W')) {
ifv->is_audio_present = 1;
} else if (aud_magic == MKTAG('P','C','M','U')) {
ifv->is_audio_present = 0;
} else {
avpriv_request_sample(s, "Unknown audio codec %x", aud_magic);
}
avio_skip(s->pb, 0x44);
ifv->total_vframes = avio_rl32(s->pb);
ifv->total_aframes = avio_rl32(s->pb);
return 0;
}
static int ifv_read_header(AVFormatContext *s)
{
IFVContext *ifv = s->priv_data;
AVStream *st;
int ret;
ret = parse_header(s);
if (ret < 0)
return ret;
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
st->codecpar->codec_id = AV_CODEC_ID_H264;
st->codecpar->width = ifv->width;
st->codecpar->height = ifv->height;
st->start_time = 0;
ifv->video_stream_index = st->index;
avpriv_set_pts_info(st, 32, 1, 1000);
if (ifv->is_audio_present) {
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE;
st->codecpar->channels = 1;
st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
st->codecpar->sample_rate = ifv->sample_rate;
ifv->audio_stream_index = st->index;
avpriv_set_pts_info(st, 32, 1, 1000);
}
/*read video index*/
avio_seek(s->pb, 0xf8, SEEK_SET);
ret = read_index(s, AVMEDIA_TYPE_VIDEO, 0);
if (ret < 0)
return ret;
if (ifv->is_audio_present) {
/*read audio index*/
avio_seek(s->pb, 0x14918, SEEK_SET);
ret = read_index(s, AVMEDIA_TYPE_AUDIO, 0);
if (ret < 0)
return ret;
}
ifv->next_video_index = 0;
ifv->next_audio_index = 0;
return 0;
}
static int ifv_read_packet(AVFormatContext *s, AVPacket *pkt)
{
IFVContext *ifv = s->priv_data;
AVStream *st;
AVIndexEntry *ev, *ea, *e_next;
int ret;
ev = ea = e_next = NULL;
if (ifv->next_video_index < ifv->total_vframes) {
st = s->streams[ifv->video_stream_index];
if (ifv->next_video_index < st->internal->nb_index_entries)
e_next = ev = &st->internal->index_entries[ifv->next_video_index];
}
if (ifv->is_audio_present &&
ifv->next_audio_index < ifv->total_aframes) {
st = s->streams[ifv->audio_stream_index];
if (ifv->next_audio_index < st->internal->nb_index_entries) {
ea = &st->internal->index_entries[ifv->next_audio_index];
if (!ev || ea->timestamp < ev->timestamp)
e_next = ea;
}
}
if (!ev) {
uint64_t vframes, aframes;
if (ifv->is_audio_present && !ea) {
/*read new video and audio indexes*/
ifv->next_video_index = ifv->total_vframes;
ifv->next_audio_index = ifv->total_aframes;
avio_skip(s->pb, 0x1c);
vframes = ifv->total_vframes + (uint64_t)avio_rl32(s->pb);
aframes = ifv->total_aframes + (uint64_t)avio_rl32(s->pb);
if (vframes > INT_MAX || aframes > INT_MAX)
return AVERROR_INVALIDDATA;
ifv->total_vframes = vframes;
ifv->total_aframes = aframes;
avio_skip(s->pb, 0xc);
if (avio_feof(s->pb))
return AVERROR_EOF;
ret = read_index(s, AVMEDIA_TYPE_VIDEO, ifv->next_video_index);
if (ret < 0)
return ret;
ret = read_index(s, AVMEDIA_TYPE_AUDIO, ifv->next_audio_index);
if (ret < 0)
return ret;
return 0;
} else if (!ifv->is_audio_present) {
/*read new video index*/
ifv->next_video_index = ifv->total_vframes;
avio_skip(s->pb, 0x1c);
vframes = ifv->total_vframes + (uint64_t)avio_rl32(s->pb);
if (vframes > INT_MAX)
return AVERROR_INVALIDDATA;
ifv->total_vframes = vframes;
avio_skip(s->pb, 0x10);
if (avio_feof(s->pb))
return AVERROR_EOF;
ret = read_index(s, AVMEDIA_TYPE_VIDEO, ifv->next_video_index);
if (ret < 0)
return ret;
return 0;
}
}
if (!e_next) return AVERROR_EOF;
avio_seek(s->pb, e_next->pos, SEEK_SET);
ret = av_get_packet(s->pb, pkt, e_next->size);
if (ret < 0)
return ret;
if (e_next == ev) {
ifv->next_video_index++;
pkt->stream_index = ifv->video_stream_index;
} else {
ifv->next_audio_index++;
pkt->stream_index = ifv->audio_stream_index;
}
pkt->pts = e_next->timestamp;
pkt->pos = e_next->pos;
return 0;
}
static int ifv_read_seek(AVFormatContext *s, int stream_index, int64_t ts, int flags)
{
IFVContext *ifv = s->priv_data;
for (unsigned i = 0; i < s->nb_streams; i++) {
int index = av_index_search_timestamp(s->streams[i], ts, AVSEEK_FLAG_ANY);
if (index < 0) {
ifv->next_video_index = ifv->total_vframes - 1;
ifv->next_audio_index = ifv->total_aframes - 1;
return 0;
}
if (i == ifv->video_stream_index) {
ifv->next_video_index = index;
} else {
ifv->next_audio_index = index;
}
}
return 0;
}
const AVInputFormat ff_ifv_demuxer = {
.name = "ifv",
.long_name = NULL_IF_CONFIG_SMALL("IFV CCTV DVR"),
.priv_data_size = sizeof(IFVContext),
.extensions = "ifv",
.read_probe = ifv_probe,
.read_header = ifv_read_header,
.read_packet = ifv_read_packet,
.read_seek = ifv_read_seek,
};