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/*
* Microsoft RLE video decoder
* Copyright (C) 2003 the ffmpeg project
*
* 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
* MS RLE video decoder by Mike Melanson (melanson@pcisys.net)
* For more information about the MS RLE format, visit:
* http://www.pcisys.net/~melanson/codecs/
*
* The MS RLE decoder outputs PAL8 colorspace data.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "avcodec.h"
#include "dsputil.h"
#include "msrledec.h"
typedef struct MsrleContext {
AVCodecContext *avctx;
AVFrame frame;
GetByteContext gb;
const unsigned char *buf;
int size;
uint32_t pal[256];
} MsrleContext;
static av_cold int msrle_decode_init(AVCodecContext *avctx)
{
MsrleContext *s = avctx->priv_data;
int i;
s->avctx = avctx;
switch (avctx->bits_per_coded_sample) {
case 1:
avctx->pix_fmt = PIX_FMT_MONOWHITE;
break;
case 4:
case 8:
avctx->pix_fmt = PIX_FMT_PAL8;
break;
case 24:
avctx->pix_fmt = PIX_FMT_BGR24;
break;
default:
av_log(avctx, AV_LOG_ERROR, "unsupported bits per sample\n");
return -1;
}
avcodec_get_frame_defaults(&s->frame);
s->frame.data[0] = NULL;
if (avctx->extradata_size >= AVPALETTE_SIZE)
for (i = 0; i < AVPALETTE_SIZE/4; i++)
s->pal[i] = 0xFF<<24 | AV_RL32(avctx->extradata+4*i);
return 0;
}
static int msrle_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
MsrleContext *s = avctx->priv_data;
int istride = FFALIGN(avctx->width*avctx->bits_per_coded_sample, 32) / 8;
s->buf = buf;
s->size = buf_size;
s->frame.reference = 3;
s->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
if (avctx->reget_buffer(avctx, &s->frame)) {
av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
return -1;
}
if (avctx->bits_per_coded_sample > 1 && avctx->bits_per_coded_sample <= 8) {
const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL);
if (pal) {
s->frame.palette_has_changed = 1;
memcpy(s->pal, pal, AVPALETTE_SIZE);
}
/* make the palette available */
memcpy(s->frame.data[1], s->pal, AVPALETTE_SIZE);
}
/* FIXME how to correctly detect RLE ??? */
if (avctx->height * istride == avpkt->size) { /* assume uncompressed */
int linesize = (avctx->width * avctx->bits_per_coded_sample + 7) / 8;
uint8_t *ptr = s->frame.data[0];
uint8_t *buf = avpkt->data + (avctx->height-1)*istride;
int i, j;
for (i = 0; i < avctx->height; i++) {
if (avctx->bits_per_coded_sample == 4) {
for (j = 0; j < avctx->width - 1; j += 2) {
ptr[j+0] = buf[j>>1] >> 4;
ptr[j+1] = buf[j>>1] & 0xF;
}
if (avctx->width & 1)
ptr[j+0] = buf[j>>1] >> 4;
} else {
memcpy(ptr, buf, linesize);
}
buf -= istride;
ptr += s->frame.linesize[0];
}
} else {
bytestream2_init(&s->gb, buf, buf_size);
ff_msrle_decode(avctx, (AVPicture*)&s->frame, avctx->bits_per_coded_sample, &s->gb);
}
*data_size = sizeof(AVFrame);
*(AVFrame*)data = s->frame;
/* report that the buffer was completely consumed */
return buf_size;
}
static av_cold int msrle_decode_end(AVCodecContext *avctx)
{
MsrleContext *s = avctx->priv_data;
/* release the last frame */
if (s->frame.data[0])
avctx->release_buffer(avctx, &s->frame);
return 0;
}
AVCodec ff_msrle_decoder = {
.name = "msrle",
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_MSRLE,
.priv_data_size = sizeof(MsrleContext),
.init = msrle_decode_init,
.close = msrle_decode_end,
.decode = msrle_decode_frame,
.capabilities = CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("Microsoft RLE"),
};
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