blob: b738fcb103729d8c57b2a520f67592ce0c368736
1 | /* |
2 | * 8088flex TMV video decoder |
3 | * Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu> |
4 | * |
5 | * This file is part of FFmpeg. |
6 | * |
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. |
11 | * |
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. |
16 | * |
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 |
20 | */ |
21 | |
22 | /** |
23 | * @file |
24 | * 8088flex TMV video decoder |
25 | * @author Daniel Verkamp |
26 | * @see http://www.oldskool.org/pc/8088_Corruption |
27 | */ |
28 | |
29 | #include <string.h> |
30 | |
31 | #include "avcodec.h" |
32 | #include "internal.h" |
33 | #include "libavutil/internal.h" |
34 | #include "libavutil/xga_font_data.h" |
35 | |
36 | #include "cga_data.h" |
37 | |
38 | static int tmv_decode_frame(AVCodecContext *avctx, void *data, |
39 | int *got_frame, AVPacket *avpkt) |
40 | { |
41 | AVFrame *frame = data; |
42 | const uint8_t *src = avpkt->data; |
43 | uint8_t *dst; |
44 | unsigned char_cols = avctx->width >> 3; |
45 | unsigned char_rows = avctx->height >> 3; |
46 | unsigned x, y, fg, bg, c; |
47 | int ret; |
48 | |
49 | if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) |
50 | return ret; |
51 | |
52 | if (avpkt->size < 2*char_rows*char_cols) { |
53 | av_log(avctx, AV_LOG_ERROR, |
54 | "Input buffer too small, truncated sample?\n"); |
55 | *got_frame = 0; |
56 | return AVERROR_INVALIDDATA; |
57 | } |
58 | |
59 | frame->pict_type = AV_PICTURE_TYPE_I; |
60 | frame->key_frame = 1; |
61 | dst = frame->data[0]; |
62 | |
63 | frame->palette_has_changed = 1; |
64 | memcpy(frame->data[1], ff_cga_palette, 16 * 4); |
65 | memset(frame->data[1] + 16 * 4, 0, AVPALETTE_SIZE - 16 * 4); |
66 | |
67 | for (y = 0; y < char_rows; y++) { |
68 | for (x = 0; x < char_cols; x++) { |
69 | c = *src++; |
70 | bg = *src >> 4; |
71 | fg = *src++ & 0xF; |
72 | ff_draw_pc_font(dst + x * 8, frame->linesize[0], |
73 | avpriv_cga_font, 8, c, fg, bg); |
74 | } |
75 | dst += frame->linesize[0] * 8; |
76 | } |
77 | |
78 | *got_frame = 1; |
79 | |
80 | return avpkt->size; |
81 | } |
82 | |
83 | static av_cold int tmv_decode_init(AVCodecContext *avctx) |
84 | { |
85 | avctx->pix_fmt = AV_PIX_FMT_PAL8; |
86 | return 0; |
87 | } |
88 | |
89 | AVCodec ff_tmv_decoder = { |
90 | .name = "tmv", |
91 | .long_name = NULL_IF_CONFIG_SMALL("8088flex TMV"), |
92 | .type = AVMEDIA_TYPE_VIDEO, |
93 | .id = AV_CODEC_ID_TMV, |
94 | .init = tmv_decode_init, |
95 | .decode = tmv_decode_frame, |
96 | .capabilities = AV_CODEC_CAP_DR1, |
97 | }; |
98 |