1 /*
2 * HQX DSP routines
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 #include <stdint.h>
22
23 #include "libavutil/common.h"
24
25 #include "hqxdsp.h"
26
idct_col(int16_t * blk,const uint8_t * quant)27 static inline void idct_col(int16_t *blk, const uint8_t *quant)
28 {
29 int t0, t1, t2, t3, t4, t5, t6, t7, t8, t9, tA, tB, tC, tD, tE, tF;
30 int t10, t11, t12, t13;
31 int s0, s1, s2, s3, s4, s5, s6, s7;
32
33 s0 = (int) blk[0 * 8] * quant[0 * 8];
34 s1 = (int) blk[1 * 8] * quant[1 * 8];
35 s2 = (int) blk[2 * 8] * quant[2 * 8];
36 s3 = (int) blk[3 * 8] * quant[3 * 8];
37 s4 = (int) blk[4 * 8] * quant[4 * 8];
38 s5 = (int) blk[5 * 8] * quant[5 * 8];
39 s6 = (int) blk[6 * 8] * quant[6 * 8];
40 s7 = (int) blk[7 * 8] * quant[7 * 8];
41
42 t0 = (int)(s3 * 19266U + s5 * 12873U) >> 15;
43 t1 = (int)(s5 * 19266U - s3 * 12873U) >> 15;
44 t2 = ((int)(s7 * 4520U + s1 * 22725U) >> 15) - t0;
45 t3 = ((int)(s1 * 4520U - s7 * 22725U) >> 15) - t1;
46 t4 = t0 * 2 + t2;
47 t5 = t1 * 2 + t3;
48 t6 = t2 - t3;
49 t7 = t3 * 2 + t6;
50 t8 = (int)(t6 * 11585U) >> 14;
51 t9 = (int)(t7 * 11585U) >> 14;
52 tA = (int)(s2 * 8867U - s6 * 21407U) >> 14;
53 tB = (int)(s6 * 8867U + s2 * 21407U) >> 14;
54 tC = (s0 >> 1) - (s4 >> 1);
55 tD = (s4 >> 1) * 2 + tC;
56 tE = tC - (tA >> 1);
57 tF = tD - (tB >> 1);
58 t10 = tF - t5;
59 t11 = tE - t8;
60 t12 = tE + (tA >> 1) * 2 - t9;
61 t13 = tF + (tB >> 1) * 2 - t4;
62
63 blk[0 * 8] = t13 + t4 * 2;
64 blk[1 * 8] = t12 + t9 * 2;
65 blk[2 * 8] = t11 + t8 * 2;
66 blk[3 * 8] = t10 + t5 * 2;
67 blk[4 * 8] = t10;
68 blk[5 * 8] = t11;
69 blk[6 * 8] = t12;
70 blk[7 * 8] = t13;
71 }
72
idct_row(int16_t * blk)73 static inline void idct_row(int16_t *blk)
74 {
75 int t0, t1, t2, t3, t4, t5, t6, t7, t8, t9, tA, tB, tC, tD, tE, tF;
76 int t10, t11, t12, t13;
77
78 t0 = (blk[3] * 19266 + blk[5] * 12873) >> 14;
79 t1 = (blk[5] * 19266 - blk[3] * 12873) >> 14;
80 t2 = ((blk[7] * 4520 + blk[1] * 22725) >> 14) - t0;
81 t3 = ((blk[1] * 4520 - blk[7] * 22725) >> 14) - t1;
82 t4 = t0 * 2 + t2;
83 t5 = t1 * 2 + t3;
84 t6 = t2 - t3;
85 t7 = t3 * 2 + t6;
86 t8 = (t6 * 11585) >> 14;
87 t9 = (t7 * 11585) >> 14;
88 tA = (blk[2] * 8867 - blk[6] * 21407) >> 14;
89 tB = (blk[6] * 8867 + blk[2] * 21407) >> 14;
90 tC = blk[0] - blk[4];
91 tD = blk[4] * 2 + tC;
92 tE = tC - tA;
93 tF = tD - tB;
94 t10 = tF - t5;
95 t11 = tE - t8;
96 t12 = tE + tA * 2 - t9;
97 t13 = tF + tB * 2 - t4;
98
99 blk[0] = (t13 + t4 * 2 + 4) >> 3;
100 blk[1] = (t12 + t9 * 2 + 4) >> 3;
101 blk[2] = (t11 + t8 * 2 + 4) >> 3;
102 blk[3] = (t10 + t5 * 2 + 4) >> 3;
103 blk[4] = (t10 + 4) >> 3;
104 blk[5] = (t11 + 4) >> 3;
105 blk[6] = (t12 + 4) >> 3;
106 blk[7] = (t13 + 4) >> 3;
107 }
108
hqx_idct_put(uint16_t * dst,ptrdiff_t stride,int16_t * block,const uint8_t * quant)109 static void hqx_idct_put(uint16_t *dst, ptrdiff_t stride,
110 int16_t *block, const uint8_t *quant)
111 {
112 int i, j;
113
114 for (i = 0; i < 8; i++)
115 idct_col(block + i, quant + i);
116 for (i = 0; i < 8; i++)
117 idct_row(block + i * 8);
118
119 for (i = 0; i < 8; i++) {
120 for (j = 0; j < 8; j++) {
121 int v = av_clip_uintp2(block[j + i * 8] + 0x800, 12);
122 dst[j] = (v << 4) | (v >> 8);
123 }
124 dst += stride >> 1;
125 }
126 }
127
ff_hqxdsp_init(HQXDSPContext * c)128 av_cold void ff_hqxdsp_init(HQXDSPContext *c)
129 {
130 c->idct_put = hqx_idct_put;
131 }
132