diff --git a/libavcodec/motion_test.c b/libavcodec/motion_test.c
new file mode 100644
index 0000000000..2857eeaf9f
--- /dev/null
+++ b/libavcodec/motion_test.c
@@ -0,0 +1,133 @@
+/* motion test. (c) 2001 Gerard Lantau. */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <getopt.h>
+
+#include "dsputil.h"
+
+#include "i386/mmx.h"
+
+int pix_abs16x16_mmx(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+int pix_abs16x16_mmx1(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+int pix_abs16x16_x2_mmx(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+int pix_abs16x16_x2_mmx1(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+int pix_abs16x16_x2_c(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+int pix_abs16x16_y2_mmx(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+int pix_abs16x16_y2_mmx1(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+int pix_abs16x16_y2_c(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+int pix_abs16x16_xy2_mmx(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+int pix_abs16x16_xy2_mmx1(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+int pix_abs16x16_xy2_c(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+
+typedef int motion_func(UINT8 *blk1, UINT8 *blk2, int lx, int h);
+
+#define WIDTH 64
+#define HEIGHT 64
+
+UINT8 img1[WIDTH * HEIGHT];
+UINT8 img2[WIDTH * HEIGHT];
+
+void fill_random(UINT8 *tab, int size)
+{
+    int i;
+    for(i=0;i<size;i++) {
+#if 1
+        tab[i] = random() % 256;
+#else
+        tab[i] = i;
+#endif
+    }
+}
+
+void help(void)
+{
+    printf("motion-test [-h]\n"
+           "test motion implementations\n");
+    exit(1);
+}
+
+INT64 gettime(void)
+{
+    struct timeval tv;
+    gettimeofday(&tv,NULL);
+    return (INT64)tv.tv_sec * 1000000 + tv.tv_usec;
+}
+
+#define NB_ITS 500
+
+int dummy;
+
+void test_motion(const char *name,
+                 motion_func *test_func, motion_func *ref_func)
+{
+    int x, y, d1, d2, it;
+    UINT8 *ptr;
+    INT64 ti;
+    printf("testing '%s'\n", name);
+
+    /* test correctness */
+    for(it=0;it<20;it++) {
+
+        fill_random(img1, WIDTH * HEIGHT);
+        fill_random(img2, WIDTH * HEIGHT);
+        
+        for(y=0;y<HEIGHT-17;y++) {
+            for(x=0;x<WIDTH-17;x++) {
+                ptr = img2 + y * WIDTH + x; 
+                d1 = test_func(img1, ptr, WIDTH, 16);
+                d2 = ref_func(img1, ptr, WIDTH, 16);
+                if (d1 != d2) {
+                    printf("error: mmx=%d c=%d\n", d1, d2);
+                }
+            }
+        }
+    }
+    emms();
+    
+    /* speed test */
+    ti = gettime();
+    d1 = 0;
+    for(it=0;it<NB_ITS;it++) {
+        for(y=0;y<HEIGHT-17;y++) {
+            for(x=0;x<WIDTH-17;x++) {
+                ptr = img2 + y * WIDTH + x; 
+                d1 += test_func(img1, ptr, WIDTH, 16);
+            }
+        }
+    }
+    emms();
+    dummy = d1; /* avoid optimisation */
+    ti = gettime() - ti;
+    
+    printf("  %0.0f kop/s\n", 
+           (double)NB_ITS * (WIDTH - 16) * (HEIGHT - 16) / 
+           (double)(ti / 1000.0));
+}
+
+
+int main(int argc, char **argv)
+{
+    int c;
+    
+    for(;;) {
+        c = getopt(argc, argv, "h");
+        if (c == -1)
+            break;
+        switch(c) {
+        case 'h':
+            help();
+            break;
+        }
+    }
+               
+    printf("ffmpeg motion test\n");
+
+    test_motion("mmx", pix_abs16x16_mmx, pix_abs16x16_c);
+    test_motion("mmx_x2", pix_abs16x16_x2_mmx, pix_abs16x16_x2_c);
+    test_motion("mmx_y2", pix_abs16x16_y2_mmx, pix_abs16x16_y2_c);
+    test_motion("mmx_xy2", pix_abs16x16_xy2_mmx, pix_abs16x16_xy2_c);
+    return 0;
+}