2 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
4 * This file is part of Libav.
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.
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.
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
27 #define FFMIN(a, b) ((a) > (b) ? (b) : (a))
31 uint64_t exp16_table[21] = {
55 // 16.16 fixpoint log()
56 static int64_t log16(uint64_t a)
62 return -log16((1LL << 32) / a);
65 for (i = 20; i >= 0; i--) {
66 int64_t b = exp16_table[i];
70 a = ((a / b) << 16) + (((a % b) << 16) + b / 2) / b;
75 static uint64_t int_sqrt(uint64_t a)
81 for (s = 31; s >= 0; s--) {
82 uint64_t b = ret_sq + (1ULL << (s * 2)) + (ret << s) * 2;
91 int main(int argc, char *argv[])
99 int len = argc < 4 ? 1 : atoi(argv[3]);
100 int64_t max = (1 << (8 * len)) - 1;
101 int shift = argc < 5 ? 0 : atoi(argv[4]);
102 int skip_bytes = argc < 6 ? 0 : atoi(argv[5]);
108 printf("tiny_psnr <file1> <file2> [<elem size> [<shift> [<skip bytes>]]]\n");
109 printf("WAV headers are skipped automatically.\n");
113 f[0] = fopen(argv[1], "rb");
114 f[1] = fopen(argv[2], "rb");
115 if (!f[0] || !f[1]) {
116 fprintf(stderr, "Could not open input files.\n");
120 for (i = 0; i < 2; i++) {
122 if (fread(p, 1, 12, f[i]) != 12)
124 if (!memcmp(p, "RIFF", 4) &&
125 !memcmp(p + 8, "WAVE", 4)) {
126 if (fread(p, 1, 8, f[i]) != 8)
128 while (memcmp(p, "data", 4)) {
129 int s = p[4] | p[5] << 8 | p[6] << 16 | p[7] << 24;
130 fseek(f[i], s, SEEK_CUR);
131 if (fread(p, 1, 8, f[i]) != 8)
135 fseek(f[i], -12, SEEK_CUR);
139 fseek(f[shift < 0], abs(shift), SEEK_CUR);
141 fseek(f[0], skip_bytes, SEEK_CUR);
142 fseek(f[1], skip_bytes, SEEK_CUR);
145 int s0 = fread(buf[0], 1, SIZE, f[0]);
146 int s1 = fread(buf[1], 1, SIZE, f[1]);
148 for (j = 0; j < FFMIN(s0, s1); j++) {
149 int64_t a = buf[0][j];
150 int64_t b = buf[1][j];
153 a = (int16_t)(a | (buf[0][++j] << 8));
154 b = (int16_t)(b | (buf[1][ j] << 8));
156 sse += (a - b) * (a - b);
167 i = FFMIN(size0, size1) / len;
170 dev = int_sqrt(((sse / i) * F * F) + (((sse % i) * F * F) + i / 2) / i);
172 psnr = ((2 * log16(max << 16) + log16(i) - log16(sse)) *
173 284619LL * F + (1LL << 31)) / (1LL << 32);
175 psnr = 1000 * F - 1; // floating point free infinity :)
177 printf("stddev:%5d.%02d PSNR:%3d.%02d MAXDIFF:%5d bytes:%9d/%9d\n",
178 (int)(dev / F), (int)(dev % F),
179 (int)(psnr / F), (int)(psnr % F),
180 maxdist, size0, size1);