tests/tiny_psnr.c

   1 /*
   2  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
   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 <stdio.h>
  22 #include <stdlib.h>
  23 #include <inttypes.h>
  24 #include <assert.h>
  25
  26 #define FFMIN(a,b) ((a) > (b) ? (b) : (a))
  27 #define F 100
  28 #define SIZE 2048
  29
  30 uint64_t exp16_table[21]={
  31      65537,
  32      65538,
  33      65540,
  34      65544,
  35      65552,
  36      65568,
  37      65600,
  38      65664,
  39      65793,
  40      66050,
  41      66568,
  42      67616,
  43      69763,
  44      74262,
  45      84150,
  46     108051,
  47     178145,
  48     484249,
  49    3578144,
  50  195360063,
  51  582360139072LL,
  52 };
  53
  54 #if 0
  55 // 16.16 fixpoint exp()
  56 static unsigned int exp16(unsigned int a){
  57     int i;
  58     int out= 1<<16;
  59
  60     for(i=19;i>=0;i--){
  61         if(a&(1<<i))
  62             out= (out*exp16_table[i] + (1<<15))>>16;
  63     }
  64
  65     return out;
  66 }
  67 #endif
  68
  69 // 16.16 fixpoint log()
  70 static int64_t log16(uint64_t a){
  71     int i;
  72     int out=0;
  73
  74     if(a < 1<<16)
  75         return -log16((1LL<<32) / a);
  76     a<<=16;
  77
  78     for(i=20;i>=0;i--){
  79         int64_t b= exp16_table[i];
  80         if(a<(b<<16)) continue;
  81         out |= 1<<i;
  82         a = ((a/b)<<16) + (((a%b)<<16) + b/2)/b;
  83     }
  84     return out;
  85 }
  86
  87 static uint64_t int_sqrt(uint64_t a)
  88 {
  89     uint64_t ret=0;
  90     int s;
  91     uint64_t ret_sq=0;
  92
  93     for(s=31; s>=0; s--){
  94         uint64_t b= ret_sq + (1ULL<<(s*2)) + (ret<<s)*2;
  95         if(b<=a){
  96             ret_sq=b;
  97             ret+= 1ULL<<s;
  98         }
  99     }
 100     return ret;
 101 }
 102
 103 int main(int argc,char* argv[]){
 104     int i, j;
 105     uint64_t sse=0;
 106     uint64_t dev;
 107     FILE *f[2];
 108     uint8_t buf[2][SIZE];
 109     uint64_t psnr;
 110     int len= argc<4 ? 1 : atoi(argv[3]);
 111     int64_t max= (1<<(8*len))-1;
 112     int shift= argc<5 ? 0 : atoi(argv[4]);
 113     int skip_bytes = argc<6 ? 0 : atoi(argv[5]);
 114     int size0=0;
 115     int size1=0;
 116
 117     if(argc<3){
 118         printf("tiny_psnr <file1> <file2> [<elem size> [<shift> [<skip bytes>]]]\n");
 119         printf("For WAV files use the following:\n");
 120         printf("./tiny_psnr file1.wav file2.wav 2 0 44 to skip the header.\n");
 121         return -1;
 122     }
 123
 124     f[0]= fopen(argv[1], "rb");
 125     f[1]= fopen(argv[2], "rb");
 126     if(!f[0] || !f[1]){
 127         fprintf(stderr, "Could not open input files.\n");
 128         return -1;
 129     }
 130     fseek(f[shift<0], shift < 0 ? -shift : shift, SEEK_SET);
 131
 132     fseek(f[0],skip_bytes,SEEK_CUR);
 133     fseek(f[1],skip_bytes,SEEK_CUR);
 134
 135     for(;;){
 136         int s0= fread(buf[0], 1, SIZE, f[0]);
 137         int s1= fread(buf[1], 1, SIZE, f[1]);
 138
 139         for(j=0; j<FFMIN(s0,s1); j++){
 140             int64_t a= buf[0][j];
 141             int64_t b= buf[1][j];
 142             if(len==2){
 143                 a= (int16_t)(a | (buf[0][++j]<<8));
 144                 b= (int16_t)(b | (buf[1][  j]<<8));
 145             }
 146             sse += (a-b) * (a-b);
 147         }
 148         size0 += s0;
 149         size1 += s1;
 150         if(s0+s1<=0)
 151             break;
 152     }
 153
 154     i= FFMIN(size0,size1)/len;
 155     if(!i) i=1;
 156     dev= int_sqrt( ((sse/i)*F*F) + (((sse%i)*F*F) + i/2)/i );
 157     if(sse)
 158         psnr= ((2*log16(max<<16) + log16(i) - log16(sse))*284619LL*F + (1<<31)) / (1LL<<32);
 159     else
 160         psnr= 1000*F-1; //floating point free infinity :)
 161
 162     printf("stddev:%5d.%02d PSNR:%3d.%02d bytes:%9d/%9d\n",
 163         (int)(dev/F), (int)(dev%F),
 164         (int)(psnr/F), (int)(psnr%F),
 165         size0, size1);
 166     return 0;
 167 }
 168
 169