1 /*
2 * Aura 2 decoder
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 /**
22 * @file
23 * Aura 2 decoder
24 */
25
30
32 {
33 /* width needs to be divisible by 4 for this codec to work */
34 if (avctx->
width & 0x3)
37
38 return 0;
39 }
40
43 {
48
49 /* prediction error tables (make it clear that they are signed values) */
50 const int8_t *delta_table = (const int8_t*)buf + 16;
51
56 }
57
58 /* pixel data starts 48 bytes in, after 3x16-byte tables */
59 buf += 48;
60
63
67
68 /* iterate through each line in the height */
69 for (y = 0; y < avctx->
height; y++) {
70 /* reset predictors */
76 Y[1] =
Y[0] + delta_table[
val & 0xF];
78
79 /* iterate through the remaining pixel groups (4 pixels/group) */
80 for (x = 1; x < (avctx->
width >> 1); x++) {
82 U[0] =
U[-1] + delta_table[
val >> 4];
83 Y[0] =
Y[-1] + delta_table[
val & 0xF];
85 V[0] =
V[-1] + delta_table[
val >> 4];
86 Y[1] =
Y[ 0] + delta_table[
val & 0xF];
88 }
92 }
93
94 *got_frame = 1;
95
97 }
98
107 };