tests/tiny_psnr.c

   1 /*
   2  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
   3  *
   4  * This file is part of Libav.
   5  *
   6  * Libav 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  * Libav 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 Libav; 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 <string.h>
  24 #include <inttypes.h>
  25 #include <assert.h>
  26
  27 #include "libavutil/intfloat.h"
  28
  29 #define FFMIN(a, b) ((a) > (b) ? (b) : (a))
  30 #define F 100
  31 #define SIZE 2048
  32
  33 uint64_t exp16_table[21] = {
  34            65537,
  35            65538,
  36            65540,
  37            65544,
  38            65552,
  39            65568,
  40            65600,
  41            65664,
  42            65793,
  43            66050,
  44            66568,
  45            67616,
  46            69763,
  47            74262,
  48            84150,
  49           108051,
  50           178145,
  51           484249,
  52          3578144,
  53        195360063,
  54     582360139072LL,
  55 };
  56
  57 // 16.16 fixpoint log()
  58 static int64_t log16(uint64_t a)
  59 {
  60     int i;
  61     int out = 0;
  62
  63     if (a < 1 << 16)
  64         return -log16((1LL << 32) / a);
  65     a <<= 16;
  66
  67     for (i = 20; i >= 0; i--) {
  68         int64_t b = exp16_table[i];
  69         if (a < (b << 16))
  70             continue;
  71         out |= 1 << i;
  72         a    = ((a / b) << 16) + (((a % b) << 16) + b / 2) / b;
  73     }
  74     return out;
  75 }
  76
  77 static uint64_t int_sqrt(uint64_t a)
  78 {
  79     uint64_t ret    = 0;
  80     uint64_t ret_sq = 0;
  81     int s;
  82
  83     for (s = 31; s >= 0; s--) {
  84         uint64_t b = ret_sq + (1ULL << (s * 2)) + (ret << s) * 2;
  85         if (b <= a) {
  86             ret_sq = b;
  87             ret   += 1ULL << s;
  88         }
  89     }
  90     return ret;
  91 }
  92
  93 static int16_t get_s16l(uint8_t *p)
  94 {
  95     union {
  96         uint16_t u;
  97         int16_t  s;
  98     } v;
  99     v.u = p[0] | p[1] << 8;
 100     return v.s;
 101 }
 102
 103 static float get_f32l(uint8_t *p)
 104 {
 105     union av_intfloat32 v;
 106     v.i = p[0] | p[1] << 8 | p[2] << 16 | p[3] << 24;
 107     return v.f;
 108 }
 109
 110 int main(int argc, char *argv[])
 111 {
 112     int i, j;
 113     uint64_t sse = 0;
 114     uint64_t dev;
 115     FILE *f[2];
 116     uint8_t buf[2][SIZE];
 117     uint64_t psnr;
 118     int len = 1;
 119     int64_t max;
 120     int shift      = argc < 5 ? 0 : atoi(argv[4]);
 121     int skip_bytes = argc < 6 ? 0 : atoi(argv[5]);
 122     int size0      = 0;
 123     int size1      = 0;
 124     int maxdist    = 0;
 125
 126     if (argc < 3) {
 127         printf("tiny_psnr <file1> <file2> [<elem size> [<shift> [<skip bytes>]]]\n");
 128         printf("WAV headers are skipped automatically.\n");
 129         return 1;
 130     }
 131
 132     if (argc > 3) {
 133         if (!strcmp(argv[3], "u8")) {
 134             len = 1;
 135         } else if (!strcmp(argv[3], "s16")) {
 136             len = 2;
 137         } else if (!strcmp(argv[3], "f32")) {
 138             len = 4;
 139         } else {
 140             char *end;
 141             len = strtol(argv[3], &end, 0);
 142             if (*end || len < 1 || len > 2) {
 143                 fprintf(stderr, "Unsupported sample format: %s\n", argv[3]);
 144                 return 1;
 145             }
 146         }
 147     }
 148
 149     max = (1LL << (8 * len)) - 1;
 150
 151     f[0] = fopen(argv[1], "rb");
 152     f[1] = fopen(argv[2], "rb");
 153     if (!f[0] || !f[1]) {
 154         fprintf(stderr, "Could not open input files.\n");
 155         return 1;
 156     }
 157
 158     for (i = 0; i < 2; i++) {
 159         uint8_t *p = buf[i];
 160         if (fread(p, 1, 12, f[i]) != 12)
 161             return 1;
 162         if (!memcmp(p, "RIFF", 4) &&
 163             !memcmp(p + 8, "WAVE", 4)) {
 164             if (fread(p, 1, 8, f[i]) != 8)
 165                 return 1;
 166             while (memcmp(p, "data", 4)) {
 167                 int s = p[4] | p[5] << 8 | p[6] << 16 | p[7] << 24;
 168                 fseek(f[i], s, SEEK_CUR);
 169                 if (fread(p, 1, 8, f[i]) != 8)
 170                     return 1;
 171             }
 172         } else {
 173             fseek(f[i], -12, SEEK_CUR);
 174         }
 175     }
 176
 177     fseek(f[shift < 0], abs(shift), SEEK_CUR);
 178
 179     fseek(f[0], skip_bytes, SEEK_CUR);
 180     fseek(f[1], skip_bytes, SEEK_CUR);
 181
 182     for (;;) {
 183         int s0 = fread(buf[0], 1, SIZE, f[0]);
 184         int s1 = fread(buf[1], 1, SIZE, f[1]);
 185
 186         for (j = 0; j < FFMIN(s0, s1); j += len) {
 187             int64_t a = buf[0][j];
 188             int64_t b = buf[1][j];
 189             int dist;
 190             if (len == 2) {
 191                 a = get_s16l(buf[0] + j);
 192                 b = get_s16l(buf[1] + j);
 193             } else if (len == 4) {
 194                 a = get_f32l(buf[0] + j) * (1 << 24);
 195                 b = get_f32l(buf[1] + j) * (1 << 24);
 196             } else {
 197                 a = buf[0][j];
 198                 b = buf[1][j];
 199             }
 200             sse += (a - b) * (a - b);
 201             dist = abs(a - b);
 202             if (dist > maxdist)
 203                 maxdist = dist;
 204         }
 205         size0 += s0;
 206         size1 += s1;
 207         if (s0 + s1 <= 0)
 208             break;
 209     }
 210
 211     i = FFMIN(size0, size1) / len;
 212     if (!i)
 213         i = 1;
 214     dev = int_sqrt(((sse / i) * F * F) + (((sse % i) * F * F) + i / 2) / i);
 215     if (sse)
 216         psnr = ((2 * log16(max << 16) + log16(i) - log16(sse)) *
 217                 284619LL * F + (1LL << 31)) / (1LL << 32);
 218     else
 219         psnr = 1000 * F - 1; // floating point free infinity :)
 220
 221     printf("stddev:%5d.%02d PSNR:%3d.%02d MAXDIFF:%5d bytes:%9d/%9d\n",
 222            (int)(dev / F), (int)(dev % F),
 223            (int)(psnr / F), (int)(psnr % F),
 224            maxdist, size0, size1);
 225     return 0;
 226 }