2 * 8088flex TMV video decoder
3 * Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu>
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * 8088flex TMV video decoder
25 * @author Daniel Verkamp
26 * @see http://www.oldskool.org/pc/8088_Corruption
32 #include "libavutil/internal.h"
33 #include "libavutil/xga_font_data.h"
37 typedef struct TMVContext {
41 static int tmv_decode_frame(AVCodecContext *avctx, void *data,
42 int *data_size, AVPacket *avpkt)
44 TMVContext *tmv = avctx->priv_data;
45 const uint8_t *src = avpkt->data;
47 unsigned char_cols = avctx->width >> 3;
48 unsigned char_rows = avctx->height >> 3;
49 unsigned x, y, fg, bg, c;
52 avctx->release_buffer(avctx, &tmv->pic);
54 if (avctx->get_buffer(avctx, &tmv->pic) < 0) {
55 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
59 if (avpkt->size < 2*char_rows*char_cols) {
60 av_log(avctx, AV_LOG_ERROR,
61 "Input buffer too small, truncated sample?\n");
66 tmv->pic.pict_type = AV_PICTURE_TYPE_I;
67 tmv->pic.key_frame = 1;
68 dst = tmv->pic.data[0];
70 tmv->pic.palette_has_changed = 1;
71 memcpy(tmv->pic.data[1], ff_cga_palette, 16 * 4);
73 for (y = 0; y < char_rows; y++) {
74 for (x = 0; x < char_cols; x++) {
78 ff_draw_pc_font(dst + x * 8, tmv->pic.linesize[0],
79 avpriv_cga_font, 8, c, fg, bg);
81 dst += tmv->pic.linesize[0] * 8;
84 *data_size = sizeof(AVFrame);
85 *(AVFrame *)data = tmv->pic;
89 static av_cold int tmv_decode_init(AVCodecContext *avctx)
91 TMVContext *tmv = avctx->priv_data;
92 avctx->pix_fmt = AV_PIX_FMT_PAL8;
93 avcodec_get_frame_defaults(&tmv->pic);
97 static av_cold int tmv_decode_close(AVCodecContext *avctx)
99 TMVContext *tmv = avctx->priv_data;
101 if (tmv->pic.data[0])
102 avctx->release_buffer(avctx, &tmv->pic);
107 AVCodec ff_tmv_decoder = {
109 .type = AVMEDIA_TYPE_VIDEO,
110 .id = AV_CODEC_ID_TMV,
111 .priv_data_size = sizeof(TMVContext),
112 .init = tmv_decode_init,
113 .close = tmv_decode_close,
114 .decode = tmv_decode_frame,
115 .capabilities = CODEC_CAP_DR1,
116 .long_name = NULL_IF_CONFIG_SMALL("8088flex TMV"),