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/*
* 8088flex TMV video decoder
* Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu>
*
* 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
*/
/**
* 8088flex TMV video decoder
* @file libavcodec/tmv.c
* @author Daniel Verkamp
* @sa http://www.oldskool.org/pc/8088_Corruption
*/
#include "avcodec.h"
#include "cga_data.h"
typedef struct TMVContext {
AVFrame pic;
} TMVContext;
static int tmv_decode_frame(AVCodecContext *avctx, void *data,
int *data_size, AVPacket *avpkt)
{
TMVContext *tmv = avctx->priv_data;
const uint8_t *src = avpkt->data;
uint8_t *dst, *dst_char;
unsigned char_cols = avctx->width >> 3;
unsigned char_rows = avctx->height >> 3;
unsigned x, y, mask, char_y, fg, bg, c;
if (tmv->pic.data[0])
avctx->release_buffer(avctx, &tmv->pic);
if (avctx->get_buffer(avctx, &tmv->pic) < 0) {
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return -1;
}
if (avpkt->size < 2*char_rows*char_cols) {
av_log(avctx, AV_LOG_ERROR,
"Input buffer too small, truncated sample?\n");
*data_size = 0;
return -1;
}
tmv->pic.pict_type = FF_I_TYPE;
tmv->pic.key_frame = 1;
dst = tmv->pic.data[0];
tmv->pic.palette_has_changed = 1;
memcpy(tmv->pic.data[1], ff_cga_palette, 16 * 4);
for (y = 0; y < char_rows; y++) {
for (x = 0; x < char_cols; x++) {
c = *src++ * 8;
bg = *src >> 4;
fg = *src++ & 0xF;
dst_char = dst + x * 8;
for (char_y = 0; char_y < 8; char_y++) {
for (mask = 0x80; mask; mask >>= 1) {
*dst_char++ = ff_cga_font[c + char_y] & mask ? fg : bg;
}
dst_char += tmv->pic.linesize[0] - 8;
}
}
dst += tmv->pic.linesize[0] * 8;
}
*data_size = sizeof(AVFrame);
*(AVFrame *)data = tmv->pic;
return avpkt->size;
}
static av_cold int tmv_decode_close(AVCodecContext *avctx)
{
TMVContext *tmv = avctx->priv_data;
if (tmv->pic.data[0])
avctx->release_buffer(avctx, &tmv->pic);
return 0;
}
AVCodec tmv_decoder = {
.name = "tmv",
.type = CODEC_TYPE_VIDEO,
.id = CODEC_ID_TMV,
.priv_data_size = sizeof(TMVContext),
.close = tmv_decode_close,
.decode = tmv_decode_frame,
.long_name = NULL_IF_CONFIG_SMALL("8088flex TMV"),
};
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