signed 16bit support
[libav.git] / tests / tiny_psnr.c
1 /*
2 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17 *
18 */
19
20 #include <stdio.h>
21 #include <inttypes.h>
22 #include <assert.h>
23
24 #define F 100
25 #define SIZE 2048
26
27 uint64_t exp16_table[21]={
28 65537,
29 65538,
30 65540,
31 65544,
32 65552,
33 65568,
34 65600,
35 65664,
36 65793,
37 66050,
38 66568,
39 67616,
40 69763,
41 74262,
42 84150,
43 108051,
44 178145,
45 484249,
46 3578144,
47 195360063,
48 582360139072LL,
49 };
50 #if 1
51 // 16.16 fixpoint exp()
52 static unsigned int exp16(unsigned int a){
53 int i;
54 int out= 1<<16;
55
56 for(i=19;i>=0;i--){
57 if(a&(1<<i))
58 out= (out*exp16_table[i] + (1<<15))>>16;
59 }
60
61 return out;
62 }
63 // 16.16 fixpoint log()
64 static int64_t log16(uint64_t a){
65 int i;
66 int out=0;
67
68 if(a < 1<<16)
69 return -log16((1LL<<32) / a);
70 a<<=16;
71
72 for(i=20;i>=0;i--){
73 int64_t b= exp16_table[i];
74 if(a<(b<<16)) continue;
75 out |= 1<<i;
76 a = ((a/b)<<16) + (((a%b)<<16) + b/2)/b;
77 }
78 return out;
79 }
80
81 #endif
82 static uint64_t int_sqrt(uint64_t a)
83 {
84 uint64_t ret=0;
85 int s;
86 uint64_t ret_sq=0;
87
88 for(s=31; s>=0; s--){
89 uint64_t b= ret_sq + (1ULL<<(s*2)) + (ret<<s)*2;
90 if(b<=a){
91 ret_sq=b;
92 ret+= 1ULL<<s;
93 }
94 }
95 return ret;
96 }
97
98 int main(int argc,char* argv[]){
99 int i, j;
100 uint64_t sse=0;
101 uint64_t dev;
102 FILE *f[2];
103 uint8_t buf[2][SIZE];
104 uint64_t psnr;
105 int len= argc<4 ? 1 : 2;
106 int64_t max= (1<<(8*len))-1;
107
108 if(argc<3){
109 printf("tiny_psnr <file1> <file2>\n");
110 return -1;
111 }
112
113 f[0]= fopen(argv[1], "rb");
114 f[1]= fopen(argv[2], "rb");
115
116 for(i=0;;){
117 if( fread(buf[0], SIZE, 1, f[0]) != 1) break;
118 if( fread(buf[1], SIZE, 1, f[1]) != 1) break;
119
120 for(j=0; j<SIZE; i++,j++){
121 int64_t a= buf[0][j];
122 int64_t b= buf[1][j];
123 if(len==2){
124 a= (int16_t)(a | (buf[0][++j]<<8));
125 b= (int16_t)(b | (buf[1][ j]<<8));
126 }
127 sse += (a-b) * (a-b);
128 }
129 }
130
131 if(!i) i=1;
132 dev= int_sqrt( ((sse/i)*F*F) + (((sse%i)*F*F) + i/2)/i );
133 if(sse)
134 psnr= ((2*log16(max<<16) + log16(i) - log16(sse))*284619LL*F + (1<<31)) / (1LL<<32);
135 else
136 psnr= 100*F-1; //floating point free infinity :)
137
138 printf("stddev:%3d.%02d PSNR:%2d.%02d bytes:%d\n",
139 (int)(dev/F), (int)(dev%F),
140 (int)(psnr/F), (int)(psnr%F),
141 i);
142 return 0;
143 }
144
145