1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
|
/*
* Bethesda VID video decoder
* Copyright (C) 2007 Nicholas Tung
*
* 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
* @brief Bethesda Softworks VID Video Decoder
* @author Nicholas Tung [ntung (at. ntung com] (2007-03)
* @see http://wiki.multimedia.cx/index.php?title=Bethsoft_VID
* @see http://www.svatopluk.com/andux/docs/dfvid.html
*/
#include "libavutil/common.h"
#include "avcodec.h"
#include "bethsoftvideo.h"
#include "bytestream.h"
#include "codec_internal.h"
#include "internal.h"
typedef struct BethsoftvidContext {
AVFrame *frame;
GetByteContext g;
} BethsoftvidContext;
static av_cold int bethsoftvid_decode_init(AVCodecContext *avctx)
{
BethsoftvidContext *vid = avctx->priv_data;
avctx->pix_fmt = AV_PIX_FMT_PAL8;
vid->frame = av_frame_alloc();
if (!vid->frame)
return AVERROR(ENOMEM);
return 0;
}
static int set_palette(BethsoftvidContext *ctx)
{
uint32_t *palette = (uint32_t *)ctx->frame->data[1];
int a;
if (bytestream2_get_bytes_left(&ctx->g) < 256*3)
return AVERROR_INVALIDDATA;
for(a = 0; a < 256; a++){
palette[a] = 0xFFU << 24 | bytestream2_get_be24u(&ctx->g) * 4;
palette[a] |= palette[a] >> 6 & 0x30303;
}
ctx->frame->palette_has_changed = 1;
return 0;
}
static int bethsoftvid_decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
BethsoftvidContext * vid = avctx->priv_data;
char block_type;
uint8_t * dst;
uint8_t * frame_end;
int remaining = avctx->width; // number of bytes remaining on a line
int wrap_to_next_line;
int code, ret;
int yoffset;
if ((ret = ff_reget_buffer(avctx, vid->frame, 0)) < 0)
return ret;
wrap_to_next_line = vid->frame->linesize[0] - avctx->width;
if (avpkt->side_data_elems > 0 &&
avpkt->side_data[0].type == AV_PKT_DATA_PALETTE) {
bytestream2_init(&vid->g, avpkt->side_data[0].data,
avpkt->side_data[0].size);
if ((ret = set_palette(vid)) < 0)
return ret;
}
bytestream2_init(&vid->g, avpkt->data, avpkt->size);
dst = vid->frame->data[0];
frame_end = vid->frame->data[0] + vid->frame->linesize[0] * avctx->height;
switch(block_type = bytestream2_get_byte(&vid->g)){
case PALETTE_BLOCK: {
*got_frame = 0;
if ((ret = set_palette(vid)) < 0) {
av_log(avctx, AV_LOG_ERROR, "error reading palette\n");
return ret;
}
return bytestream2_tell(&vid->g);
}
case VIDEO_YOFF_P_FRAME:
yoffset = bytestream2_get_le16(&vid->g);
if(yoffset >= avctx->height)
return AVERROR_INVALIDDATA;
dst += vid->frame->linesize[0] * yoffset;
case VIDEO_P_FRAME:
case VIDEO_I_FRAME:
break;
default:
return AVERROR_INVALIDDATA;
}
// main code
while((code = bytestream2_get_byte(&vid->g))){
int length = code & 0x7f;
// copy any bytes starting at the current position, and ending at the frame width
while(length > remaining){
if(code < 0x80)
bytestream2_get_buffer(&vid->g, dst, remaining);
else if(block_type == VIDEO_I_FRAME)
memset(dst, bytestream2_peek_byte(&vid->g), remaining);
length -= remaining; // decrement the number of bytes to be copied
dst += remaining + wrap_to_next_line; // skip over extra bytes at end of frame
remaining = avctx->width;
if(dst == frame_end)
goto end;
}
// copy any remaining bytes after / if line overflows
if(code < 0x80)
bytestream2_get_buffer(&vid->g, dst, length);
else if(block_type == VIDEO_I_FRAME)
memset(dst, bytestream2_get_byte(&vid->g), length);
remaining -= length;
dst += length;
}
end:
if ((ret = av_frame_ref(data, vid->frame)) < 0)
return ret;
*got_frame = 1;
return avpkt->size;
}
static av_cold int bethsoftvid_decode_end(AVCodecContext *avctx)
{
BethsoftvidContext * vid = avctx->priv_data;
av_frame_free(&vid->frame);
return 0;
}
const FFCodec ff_bethsoftvid_decoder = {
.p.name = "bethsoftvid",
.p.long_name = NULL_IF_CONFIG_SMALL("Bethesda VID video"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_BETHSOFTVID,
.priv_data_size = sizeof(BethsoftvidContext),
.init = bethsoftvid_decode_init,
.close = bethsoftvid_decode_end,
.decode = bethsoftvid_decode_frame,
.p.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};
|
