FFmpeg add mt-work folder for completeness.

third_party/ffmpeg/patched-ffmpeg-mt/mt-work/yuvcmp.c

+/*
+ * originally by Andreas Öman (andoma)
+ * some changes by Alexander Strange
+ */
+
+#include <string.h>
+#include <stdlib.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+
+int
+main(int argc, char **argv)
+{
+    int fd[2];
+    int print_pixels = 0;
+    int dump_blocks = 0;
+
+    int width;
+    int height;
+    int to_skip = 0;
+
+    if (argc < 6) {
+        fprintf(stderr, "%s [YUV file 1] [YUV file 2] width height pixelcmp|blockdump (# to skip)\n", argv[0]);
+        return 1;
+    }
+
+    width  = atoi(argv[3]);
+    height = atoi(argv[4]);
+    if (argc > 6)
+        to_skip = atoi(argv[6]);
+
+    uint8_t *Y[2], *C[2][2];
+    int i, v, c, p;
+    int lsiz = width * height;
+    int csiz = width * height / 4;
+    int x, y;
+    int cwidth = width / 2;
+    int fr = to_skip;
+    int mb;
+    char *mberrors;
+    int mb_x, mb_y;
+    uint8_t *a;
+    uint8_t *b;
+    int die = 0;
+
+    print_pixels = strstr(argv[5], "pixelcmp") ? 1 : 0;
+    dump_blocks  = strstr(argv[5], "blockdump") ? 1 : 0;
+
+    for(i = 0; i < 2; i++) {
+        Y[i] = malloc(lsiz);
+        C[0][i] = malloc(csiz);
+        C[1][i] = malloc(csiz);
+
+        fd[i] = open(argv[1 + i], O_RDONLY);
+        if(fd[i] == -1) {
+            perror("open");
+            exit(1);
+        }
+        fcntl(fd[i], F_NOCACHE, 1);
+
+        if (to_skip)
+            lseek(fd[i], to_skip * (lsiz + 2*csiz), SEEK_SET);
+    }
+
+    mb_x = width / 16;
+    mb_y = height / 16;
+
+    mberrors = malloc(mb_x * mb_y);
+
+    while(!die) {
+        memset(mberrors, 0, mb_x * mb_y);
+
+        printf("Loading frame %d\n", ++fr);
+
+        for(i = 0; i < 2; i++) {
+            v = read(fd[i], Y[i], lsiz);
+            if(v != lsiz) {
+                fprintf(stderr, "Unable to read Y from file %d, exiting\n", i + 1);
+                return 1;
+            }
+        }
+
+
+        for(c = 0; c < lsiz; c++) {
+            if(Y[0][c] != Y[1][c]) {
+                x = c % width;
+                y = c / width;
+
+                mb = x / 16 + (y / 16) * mb_x;
+
+                if(print_pixels)
+                    printf("Luma diff 0x%02x != 0x%02x at pixel (%4d,%-4d) mb(%d,%d) #%d\n",
+                           Y[0][c],
+                           Y[1][c],
+                           x, y,
+                           x / 16,
+                           y / 16,
+                           mb);
+
+                mberrors[mb] |= 1;
+            }
+        }
+
+        /* Chroma planes */
+
+        for(p = 0; p < 2; p++) {
+
+            for(i = 0; i < 2; i++) {
+                v = read(fd[i], C[p][i], csiz);
+                if(v != csiz) {
+                    fprintf(stderr, "Unable to read %c from file %d, exiting\n",
+                            "UV"[p], i + 1);
+                    return 1;
+                }
+            }
+
+            for(c = 0; c < csiz; c++) {
+                if(C[p][0][c] != C[p][1][c]) {
+                    x = c % cwidth;
+                    y = c / cwidth;
+
+                    mb = x / 8 + (y / 8) * mb_x;
+
+                    mberrors[mb] |= 2 << p;
+
+                    if(print_pixels)
+
+                        printf("c%c diff 0x%02x != 0x%02x at pixel (%4d,%-4d) "
+                               "mb(%3d,%-3d) #%d\n",
+                               p ? 'r' : 'b',
+                               C[p][0][c],
+                               C[p][1][c],
+
+                               x, y,
+                               x / 8,
+                               y / 8,
+                               x / 8 + y / 8 * cwidth / 8);
+                }
+            }
+        }
+
+        for(i = 0; i < mb_x * mb_y; i++) {
+            x = i % mb_x;
+            y = i / mb_x;
+
+            if(mberrors[i]) {
+                die = 1;
+
+                printf("MB (%3d,%-3d) %4d %d %c%c%c damaged\n",
+                       x, y, i, mberrors[i],
+                       mberrors[i] & 1 ? 'Y' : ' ',
+                       mberrors[i] & 2 ? 'U' : ' ',
+                       mberrors[i] & 4 ? 'V' : ' ');
+
+                if(dump_blocks) {
+                    a = Y[0] + x * 16 + y * 16 * width;
+                    b = Y[1] + x * 16 + y * 16 * width;
+
+                    for(y = 0; y < 16; y++) {
+                        printf("%c ", "TB"[y&1]);
+                        for(x = 0; x < 16; x++)
+                            printf("%02x%c", a[x + y * width],
+                                   a[x + y * width] != b[x + y * width] ? '<' : ' ');
+
+                        printf("| ");
+                        for(x = 0; x < 16; x++)
+                            printf("%02x%c", b[x + y * width],
+                                   a[x + y * width] != b[x + y * width] ? '<' : ' ');
+
+                        printf("\n");
+                    }
+                }
+            }
+        }
+    }
+
+    return 0;
+}