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/*
* Microsoft Paint (MSP) version 2 decoder
* Copyright (c) 2020 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
* Microsoft Paint (MSP) version 2 decoder
*/
#include "avcodec.h"
#include "bytestream.h"
#include "codec_internal.h"
#include "decode.h"
static int msp2_decode_frame(AVCodecContext *avctx, AVFrame *p,
int *got_frame, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
int ret;
unsigned int x, y, width = (avctx->width + 7) / 8;
GetByteContext idx, gb;
if (buf_size <= 2 * avctx->height)
return AVERROR_INVALIDDATA;
avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;
if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
return ret;
bytestream2_init(&idx, buf, 2 * avctx->height);
buf += 2 * avctx->height;
buf_size -= 2 * avctx->height;
for (y = 0; y < avctx->height; y++) {
unsigned int pkt_size = bytestream2_get_le16(&idx);
if (!pkt_size) {
memset(p->data[0] + y * p->linesize[0], 0xFF, width);
continue;
}
if (pkt_size > buf_size) {
av_log(avctx, AV_LOG_WARNING, "image probably corrupt\n");
pkt_size = buf_size;
}
bytestream2_init(&gb, buf, pkt_size);
x = 0;
while (bytestream2_get_bytes_left(&gb) && x < width) {
int size = bytestream2_get_byte(&gb);
if (size) {
size = FFMIN(size, bytestream2_get_bytes_left(&gb));
memcpy(p->data[0] + y * p->linesize[0] + x, gb.buffer, FFMIN(size, width - x));
bytestream2_skip(&gb, size);
} else {
int value;
size = bytestream2_get_byte(&gb);
if (!size)
avpriv_request_sample(avctx, "escape value");
value = bytestream2_get_byte(&gb);
memset(p->data[0] + y * p->linesize[0] + x, value, FFMIN(size, width - x));
}
x += size;
}
buf += pkt_size;
buf_size -= pkt_size;
}
*got_frame = 1;
return buf_size;
}
const FFCodec ff_msp2_decoder = {
.p.name = "msp2",
CODEC_LONG_NAME("Microsoft Paint (MSP) version 2"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_MSP2,
.p.capabilities = AV_CODEC_CAP_DR1,
FF_CODEC_DECODE_CB(msp2_decode_frame),
};
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