ffmpeg/libavformat/frmdec.c

114 lines
3.0 KiB
C

/*
* Megalux Frame demuxer
* Copyright (c) 2010 Peter Ross <pross@xvid.org>
*
* 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
*/
/**
* @file
* Megalux Frame demuxer
*/
#include "libavutil/imgutils.h"
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "demux.h"
static const enum AVPixelFormat frm_pix_fmt_tags[] = {
AV_PIX_FMT_RGB555,
AV_PIX_FMT_RGB0,
AV_PIX_FMT_RGB24,
AV_PIX_FMT_BGR0,
AV_PIX_FMT_BGRA,
};
typedef struct {
int count;
} FrmContext;
static int frm_read_probe(const AVProbeData *p)
{
if (p->buf_size > 8 &&
p->buf[0] == 'F' && p->buf[1] == 'R' && p->buf[2] == 'M' &&
AV_RL16(&p->buf[4]) && AV_RL16(&p->buf[6]))
return AVPROBE_SCORE_MAX / 4;
return 0;
}
static int frm_read_header(AVFormatContext *avctx)
{
AVIOContext *pb = avctx->pb;
AVStream *st = avformat_new_stream(avctx, 0);
unsigned idx;
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
st->codecpar->codec_id = AV_CODEC_ID_RAWVIDEO;
avio_skip(pb, 3);
idx = avio_r8(pb) - 1;
if (idx >= FF_ARRAY_ELEMS(frm_pix_fmt_tags))
return AVERROR_INVALIDDATA;
st->codecpar->format = frm_pix_fmt_tags[idx];
st->codecpar->codec_tag = 0;
st->codecpar->width = avio_rl16(pb);
st->codecpar->height = avio_rl16(pb);
return 0;
}
static int frm_read_packet(AVFormatContext *avctx, AVPacket *pkt)
{
FrmContext *s = avctx->priv_data;
AVCodecParameters *par = avctx->streams[0]->codecpar;
int packet_size, ret;
if (s->count)
return AVERROR_EOF;
packet_size = av_image_get_buffer_size(par->format, par->width, par->height, 1);
if (packet_size < 0)
return AVERROR_INVALIDDATA;
ret = av_get_packet(avctx->pb, pkt, packet_size);
if (ret < 0)
return ret;
if (par->format == AV_PIX_FMT_BGRA) {
int i;
for (i = 3; i + 1 <= pkt->size; i += 4)
pkt->data[i] = 0xFF - pkt->data[i];
}
pkt->stream_index = 0;
s->count++;
return 0;
}
const FFInputFormat ff_frm_demuxer = {
.p.name = "frm",
.p.long_name = NULL_IF_CONFIG_SMALL("Megalux Frame"),
.priv_data_size = sizeof(FrmContext),
.read_probe = frm_read_probe,
.read_header = frm_read_header,
.read_packet = frm_read_packet,
};