ffmpeg/libavcodec/frwu.c

126 lines
4.1 KiB
C

/*
* Forward Uncompressed
*
* Copyright (c) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
*
* 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 "avcodec.h"
#include "bytestream.h"
#include "codec_internal.h"
#include "decode.h"
#include "libavutil/opt.h"
typedef struct {
AVClass *av_class;
int change_field_order;
} FRWUContext;
static av_cold int decode_init(AVCodecContext *avctx)
{
if (avctx->width & 1) {
av_log(avctx, AV_LOG_ERROR, "frwu needs even width\n");
return AVERROR(EINVAL);
}
avctx->pix_fmt = AV_PIX_FMT_UYVY422;
return 0;
}
static int decode_frame(AVCodecContext *avctx, AVFrame *pic,
int *got_frame, AVPacket *avpkt)
{
FRWUContext *s = avctx->priv_data;
int field, ret;
const uint8_t *buf = avpkt->data;
const uint8_t *buf_end = buf + avpkt->size;
if (avpkt->size < avctx->width * 2 * avctx->height + 4 + 2*8) {
av_log(avctx, AV_LOG_ERROR, "Packet is too small.\n");
return AVERROR_INVALIDDATA;
}
if (bytestream_get_le32(&buf) != MKTAG('F', 'R', 'W', '1')) {
av_log(avctx, AV_LOG_ERROR, "incorrect marker\n");
return AVERROR_INVALIDDATA;
}
if ((ret = ff_get_buffer(avctx, pic, 0)) < 0)
return ret;
for (field = 0; field < 2; field++) {
int i;
int field_h = (avctx->height + !field) >> 1;
int field_size, min_field_size = avctx->width * 2 * field_h;
uint8_t *dst = pic->data[0];
if (buf_end - buf < 8)
return AVERROR_INVALIDDATA;
buf += 4; // flags? 0x80 == bottom field maybe?
field_size = bytestream_get_le32(&buf);
if (field_size < min_field_size) {
av_log(avctx, AV_LOG_ERROR, "Field size %i is too small (required %i)\n", field_size, min_field_size);
return AVERROR_INVALIDDATA;
}
if (buf_end - buf < field_size) {
av_log(avctx, AV_LOG_ERROR, "Packet is too small, need %i, have %i\n", field_size, (int)(buf_end - buf));
return AVERROR_INVALIDDATA;
}
if (field ^ s->change_field_order) {
dst += pic->linesize[0];
} else if (s->change_field_order) {
dst += 2 * pic->linesize[0];
}
for (i = 0; i < field_h; i++) {
if (s->change_field_order && field && i == field_h - 1)
dst = pic->data[0];
memcpy(dst, buf, avctx->width * 2);
buf += avctx->width * 2;
dst += pic->linesize[0] << 1;
}
buf += field_size - min_field_size;
}
*got_frame = 1;
return avpkt->size;
}
static const AVOption frwu_options[] = {
{"change_field_order", "Change field order", offsetof(FRWUContext, change_field_order), AV_OPT_TYPE_BOOL,
{.i64 = 0}, 0, 1, AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM},
{NULL}
};
static const AVClass frwu_class = {
.class_name = "frwu Decoder",
.item_name = av_default_item_name,
.option = frwu_options,
.version = LIBAVUTIL_VERSION_INT,
};
const FFCodec ff_frwu_decoder = {
.p.name = "frwu",
CODEC_LONG_NAME("Forward Uncompressed"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_FRWU,
.priv_data_size = sizeof(FRWUContext),
.init = decode_init,
FF_CODEC_DECODE_CB(decode_frame),
.p.capabilities = AV_CODEC_CAP_DR1,
.p.priv_class = &frwu_class,
};