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
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
|
/*
* Intel Indeo 2 codec
* Copyright (c) 2005 Konstantin Shishkov
*
* 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 indeo2.c
* Intel Indeo 2 decoder.
*/
#define ALT_BITSTREAM_READER_LE
#include "avcodec.h"
#include "bitstream.h"
#include "indeo2data.h"
typedef struct Ir2Context{
AVCodecContext *avctx;
AVFrame picture;
GetBitContext gb;
int decode_delta;
} Ir2Context;
#define CODE_VLC_BITS 14
static VLC ir2_vlc;
/* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */
static inline int ir2_get_code(GetBitContext *gb)
{
return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1;
}
static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
const uint8_t *table)
{
int i;
int j;
int out = 0;
int c;
int t;
if(width&1)
return -1;
/* first line contain absolute values, other lines contain deltas */
while (out < width){
c = ir2_get_code(&ctx->gb);
if(c >= 0x80) { /* we have a run */
c -= 0x7F;
if(out + c*2 > width)
return -1;
for (i = 0; i < c * 2; i++)
dst[out++] = 0x80;
} else { /* copy two values from table */
dst[out++] = table[c * 2];
dst[out++] = table[(c * 2) + 1];
}
}
dst += stride;
for (j = 1; j < height; j++){
out = 0;
while (out < width){
c = ir2_get_code(&ctx->gb);
if(c >= 0x80) { /* we have a skip */
c -= 0x7F;
if(out + c*2 > width)
return -1;
for (i = 0; i < c * 2; i++) {
dst[out] = dst[out - stride];
out++;
}
} else { /* add two deltas from table */
t = dst[out - stride] + (table[c * 2] - 128);
t= clip_uint8(t);
dst[out] = t;
out++;
t = dst[out - stride] + (table[(c * 2) + 1] - 128);
t= clip_uint8(t);
dst[out] = t;
out++;
}
}
dst += stride;
}
return 0;
}
static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
const uint8_t *table)
{
int j;
int out = 0;
int c;
int t;
if(width&1)
return -1;
for (j = 0; j < height; j++){
out = 0;
while (out < width){
c = ir2_get_code(&ctx->gb);
if(c >= 0x80) { /* we have a skip */
c -= 0x7F;
out += c * 2;
} else { /* add two deltas from table */
t = dst[out] + (((table[c * 2] - 128)*3) >> 2);
t= clip_uint8(t);
dst[out] = t;
out++;
t = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);
t= clip_uint8(t);
dst[out] = t;
out++;
}
}
dst += stride;
}
return 0;
}
static int ir2_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
uint8_t *buf, int buf_size)
{
Ir2Context * const s = avctx->priv_data;
AVFrame *picture = data;
AVFrame * const p= (AVFrame*)&s->picture;
int start;
if(p->data[0])
avctx->release_buffer(avctx, p);
p->reference = 1;
p->buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
if (avctx->reget_buffer(avctx, p)) {
av_log(s->avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
return -1;
}
s->decode_delta = buf[18];
/* decide whether frame uses deltas or not */
#ifndef ALT_BITSTREAM_READER_LE
for (i = 0; i < buf_size; i++)
buf[i] = ff_reverse[buf[i]];
#endif
start = 48; /* hardcoded for now */
init_get_bits(&s->gb, buf + start, buf_size - start);
if (s->decode_delta) { /* intraframe */
ir2_decode_plane(s, avctx->width, avctx->height,
s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
/* swapped U and V */
ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
} else { /* interframe */
ir2_decode_plane_inter(s, avctx->width, avctx->height,
s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
/* swapped U and V */
ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
}
*picture= *(AVFrame*)&s->picture;
*data_size = sizeof(AVPicture);
return buf_size;
}
static int ir2_decode_init(AVCodecContext *avctx){
Ir2Context * const ic = avctx->priv_data;
ic->avctx = avctx;
avctx->pix_fmt= PIX_FMT_YUV410P;
if (!ir2_vlc.table)
init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
&ir2_codes[0][1], 4, 2,
#ifdef ALT_BITSTREAM_READER_LE
&ir2_codes[0][0], 4, 2, INIT_VLC_USE_STATIC | INIT_VLC_LE);
#else
&ir2_codes[0][0], 4, 2, INIT_VLC_USE_STATIC);
#endif
return 0;
}
AVCodec indeo2_decoder = {
"indeo2",
CODEC_TYPE_VIDEO,
CODEC_ID_INDEO2,
sizeof(Ir2Context),
ir2_decode_init,
NULL,
NULL,
ir2_decode_frame,
CODEC_CAP_DR1,
};
|
