ref: c96a8dcb5b1c02c275c0909a63a06aa424308f32
dir: /tools/tiny_ssim.c/
/*
* Copyright (c) 2016 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include <errno.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "vpx/vpx_integer.h"
void vp8_ssim_parms_8x8_c(unsigned char *s, int sp, unsigned char *r, int rp,
uint32_t *sum_s, uint32_t *sum_r, uint32_t *sum_sq_s,
uint32_t *sum_sq_r, uint32_t *sum_sxr) {
int i, j;
for (i = 0; i < 8; i++, s += sp, r += rp) {
for (j = 0; j < 8; j++) {
*sum_s += s[j];
*sum_r += r[j];
*sum_sq_s += s[j] * s[j];
*sum_sq_r += r[j] * r[j];
*sum_sxr += s[j] * r[j];
}
}
}
static const int64_t cc1 = 26634; // (64^2*(.01*255)^2
static const int64_t cc2 = 239708; // (64^2*(.03*255)^2
static double similarity(uint32_t sum_s, uint32_t sum_r, uint32_t sum_sq_s,
uint32_t sum_sq_r, uint32_t sum_sxr, int count) {
int64_t ssim_n, ssim_d;
int64_t c1, c2;
// scale the constants by number of pixels
c1 = (cc1 * count * count) >> 12;
c2 = (cc2 * count * count) >> 12;
ssim_n = (2 * sum_s * sum_r + c1) *
((int64_t)2 * count * sum_sxr - (int64_t)2 * sum_s * sum_r + c2);
ssim_d = (sum_s * sum_s + sum_r * sum_r + c1) *
((int64_t)count * sum_sq_s - (int64_t)sum_s * sum_s +
(int64_t)count * sum_sq_r - (int64_t)sum_r * sum_r + c2);
return ssim_n * 1.0 / ssim_d;
}
static double ssim_8x8(unsigned char *s, int sp, unsigned char *r, int rp) {
uint32_t sum_s = 0, sum_r = 0, sum_sq_s = 0, sum_sq_r = 0, sum_sxr = 0;
vp8_ssim_parms_8x8_c(s, sp, r, rp, &sum_s, &sum_r, &sum_sq_s, &sum_sq_r,
&sum_sxr);
return similarity(sum_s, sum_r, sum_sq_s, sum_sq_r, sum_sxr, 64);
}
// We are using a 8x8 moving window with starting location of each 8x8 window
// on the 4x4 pixel grid. Such arrangement allows the windows to overlap
// block boundaries to penalize blocking artifacts.
double vp8_ssim2(unsigned char *img1, unsigned char *img2, int stride_img1,
int stride_img2, int width, int height) {
int i, j;
int samples = 0;
double ssim_total = 0;
// sample point start with each 4x4 location
for (i = 0; i <= height - 8;
i += 4, img1 += stride_img1 * 4, img2 += stride_img2 * 4) {
for (j = 0; j <= width - 8; j += 4) {
double v = ssim_8x8(img1 + j, stride_img1, img2 + j, stride_img2);
ssim_total += v;
samples++;
}
}
ssim_total /= samples;
return ssim_total;
}
static uint64_t calc_plane_error(uint8_t *orig, int orig_stride, uint8_t *recon,
int recon_stride, unsigned int cols,
unsigned int rows) {
unsigned int row, col;
uint64_t total_sse = 0;
int diff;
for (row = 0; row < rows; row++) {
for (col = 0; col < cols; col++) {
diff = orig[col] - recon[col];
total_sse += diff * diff;
}
orig += orig_stride;
recon += recon_stride;
}
return total_sse;
}
#define MAX_PSNR 100
double vp9_mse2psnr(double samples, double peak, double mse) {
double psnr;
if (mse > 0.0)
psnr = 10.0 * log10(peak * peak * samples / mse);
else
psnr = MAX_PSNR; // Limit to prevent / 0
if (psnr > MAX_PSNR) psnr = MAX_PSNR;
return psnr;
}
int main(int argc, char *argv[]) {
FILE *f[2];
uint8_t *buf[2];
int w, h, n_frames, tl_skip = 0, tl_skips_remaining = 0;
double ssim = 0, psnravg = 0, psnrglb = 0;
double ssimy, ssimu, ssimv;
uint64_t psnry, psnru, psnrv;
if (argc < 4) {
fprintf(stderr, "Usage: %s file1.yuv file2.yuv WxH [tl_skip={0,1,3}]\n",
argv[0]);
return 1;
}
f[0] = strcmp(argv[1], "-") ? fopen(argv[1], "rb") : stdin;
f[1] = strcmp(argv[2], "-") ? fopen(argv[2], "rb") : stdin;
sscanf(argv[3], "%dx%d", &w, &h);
// Number of frames to skip from file1.yuv for every frame used. Normal values
// 0, 1 and 3 correspond to TL2, TL1 and TL0 respectively for a 3TL encoding
// in mode 10. 7 would be reasonable for comparing TL0 of a 4-layer encoding.
if (argc > 4) {
sscanf(argv[4], "%d", &tl_skip);
}
if (!f[0] || !f[1]) {
fprintf(stderr, "Could not open input files: %s\n", strerror(errno));
return 1;
}
if (w <= 0 || h <= 0 || w & 1 || h & 1) {
fprintf(stderr, "Invalid size %dx%d\n", w, h);
return 1;
}
buf[0] = malloc(w * h * 3 / 2);
buf[1] = malloc(w * h * 3 / 2);
n_frames = 0;
while (1) {
size_t r1, r2;
r1 = fread(buf[0], w * h * 3 / 2, 1, f[0]);
if (r1) {
// Reading parts of file1.yuv that were not used in temporal layer.
if (tl_skips_remaining > 0) {
--tl_skips_remaining;
continue;
}
// Use frame, but skip |tl_skip| after it.
tl_skips_remaining = tl_skip;
}
r2 = fread(buf[1], w * h * 3 / 2, 1, f[1]);
if (r1 && r2 && r1 != r2) {
fprintf(stderr, "Failed to read data: %s [%d/%d]\n", strerror(errno),
(int)r1, (int)r2);
return 1;
} else if (r1 == 0 || r2 == 0) {
break;
}
#define psnr_and_ssim(ssim, psnr, buf0, buf1, w, h) \
ssim = vp8_ssim2(buf0, buf1, w, w, w, h); \
psnr = calc_plane_error(buf0, w, buf1, w, w, h);
psnr_and_ssim(ssimy, psnry, buf[0], buf[1], w, h);
psnr_and_ssim(ssimu, psnru, buf[0] + w * h, buf[1] + w * h, w / 2, h / 2);
psnr_and_ssim(ssimv, psnrv, buf[0] + w * h * 5 / 4, buf[1] + w * h * 5 / 4,
w / 2, h / 2);
ssim += 0.8 * ssimy + 0.1 * (ssimu + ssimv);
psnravg +=
vp9_mse2psnr(w * h * 6 / 4, 255.0, (double)psnry + psnru + psnrv);
psnrglb += psnry + psnru + psnrv;
n_frames++;
}
free(buf[0]);
free(buf[1]);
ssim /= n_frames;
psnravg /= n_frames;
psnrglb = vp9_mse2psnr((double)n_frames * w * h * 6 / 4, 255.0, psnrglb);
printf("AvgPSNR: %lf\n", psnravg);
printf("GlbPSNR: %lf\n", psnrglb);
printf("SSIM: %lf\n", 100 * pow(ssim, 8.0));
printf("Nframes: %d\n", n_frames);
if (strcmp(argv[1], "-")) fclose(f[0]);
if (strcmp(argv[2], "-")) fclose(f[1]);
return 0;
}