@@ -90,6 +90,7 @@ typedef struct {

     Transform last;            ///< Transform from last frame

     int refcount;              ///< Number of reference frames (defines averaging window)

     FILE *fp;

+    Transform avg;

 } DeshakeContext;

 static int cmp(void const *ca, void const *cb)

@@ -404,15 +405,7 @@ static void end_frame(AVFilterLink *link)

     AVFilterBufferRef *in  = link->cur_buf;

     AVFilterBufferRef *out = link->dst->outputs[0]->out_buf;

     Transform t;

-    static float matrix[9];

-    static Transform avg = {

-        .vector = {

-            .x = 0,

-            .y = 0

-        },

-        .angle = 0,

-        .zoom = 0.0f

-    };

+    float matrix[9];

     float alpha = 2.0 / deshake->refcount;

     char tmp[256];

     Transform orig;

@@ -427,17 +420,17 @@ static void end_frame(AVFilterLink *link)

     orig.zoom = t.zoom;

     // Generate a one-sided moving exponential average

-    avg.vector.x = alpha * t.vector.x + (1.0 - alpha) * avg.vector.x;

-    avg.vector.y = alpha * t.vector.y + (1.0 - alpha) * avg.vector.y;

-    avg.angle = alpha * t.angle + (1.0 - alpha) * avg.angle;

-    avg.zoom = alpha * t.zoom + (1.0 - alpha) * avg.zoom;

+    deshake->avg.vector.x = alpha * t.vector.x + (1.0 - alpha) * deshake->avg.vector.x;

+    deshake->avg.vector.y = alpha * t.vector.y + (1.0 - alpha) * deshake->avg.vector.y;

+    deshake->avg.angle = alpha * t.angle + (1.0 - alpha) * deshake->avg.angle;

+    deshake->avg.zoom = alpha * t.zoom + (1.0 - alpha) * deshake->avg.zoom;

     // Remove the average from the current motion to detect the motion that

     // is not on purpose, just as jitter from bumping the camera

-    t.vector.x -= avg.vector.x;

-    t.vector.y -= avg.vector.y;

-    t.angle -= avg.angle;

-    t.zoom -= avg.zoom;

+    t.vector.x -= deshake->avg.vector.x;

+    t.vector.y -= deshake->avg.vector.y;

+    t.angle -= deshake->avg.angle;

+    t.zoom -= deshake->avg.zoom;

     // Invert the motion to undo it

     t.vector.x *= -1;

@@ -445,7 +438,7 @@ static void end_frame(AVFilterLink *link)

     t.angle *= -1;

     // Write statistics to file

-    snprintf(tmp, 256, "%f, %f, %f, %f, %f, %f, %f, %f, %f, %f, %f, %f\n", orig.vector.x, avg.vector.x, t.vector.x, orig.vector.y, avg.vector.y, t.vector.y, orig.angle, avg.angle, t.angle, orig.zoom, avg.zoom, t.zoom);

+    snprintf(tmp, 256, "%f, %f, %f, %f, %f, %f, %f, %f, %f, %f, %f, %f\n", orig.vector.x, deshake->avg.vector.x, t.vector.x, orig.vector.y, deshake->avg.vector.y, t.vector.y, orig.angle, deshake->avg.angle, t.angle, orig.zoom, deshake->avg.zoom, t.zoom);

     fwrite(tmp, sizeof(char), strlen(tmp), deshake->fp);

     // Turn relative current frame motion into absolute by adding it to the