diff --git a/src/enc/alpha_enc.c b/src/enc/alpha_enc.c
index 56b46153..514d6d0e 100644
--- a/src/enc/alpha_enc.c
+++ b/src/enc/alpha_enc.c
@@ -217,7 +217,7 @@ static uint32_t GetFilterMap(const uint8_t* alpha, int width, int height,
     // For low number of colors, NONE yields better compression.
     filter = (num_colors <= kMinColorsForFilterNone)
                  ? WEBP_FILTER_NONE
-                 : WebPEstimateBestFilter(alpha, width, height, width);
+                 : WebPEstimateBestFilter(alpha, width, height);
     bit_map |= 1 << filter;
     // For large number of colors, try FILTER_NONE in addition to the best
     // filter as well.
diff --git a/src/utils/filters_utils.c b/src/utils/filters_utils.c
index 48b1606f..fec7bc5d 100644
--- a/src/utils/filters_utils.c
+++ b/src/utils/filters_utils.c
@@ -35,14 +35,14 @@ static WEBP_INLINE int GradientPredictor(uint8_t a, uint8_t b, uint8_t c) {
 
 WEBP_FILTER_TYPE WebPEstimateBestFilter(
     const uint8_t* WEBP_COUNTED_BY((size_t)width* height) data, int width,
-    int height, int stride) {
+    int height) {
   int i, j;
   int bins[WEBP_FILTER_LAST][SMAX];
   WEBP_UNSAFE_MEMSET(bins, 0, sizeof(bins));
 
   // We only sample every other pixels. That's enough.
   for (j = 2; j < height - 1; j += 2) {
-    const uint8_t* const p = data + j * stride;
+    const uint8_t* const p = data + j * width;
     int mean = p[0];
     for (i = 2; i < width - 1; i += 2) {
       const int diff0 = SDIFF(p[i], mean);
diff --git a/src/utils/filters_utils.h b/src/utils/filters_utils.h
index d852c23c..a4a8fd12 100644
--- a/src/utils/filters_utils.h
+++ b/src/utils/filters_utils.h
@@ -27,7 +27,7 @@ extern "C" {
 // Fast estimate of a potentially good filter.
 WEBP_FILTER_TYPE WebPEstimateBestFilter(
     const uint8_t* WEBP_COUNTED_BY((size_t)width* height) data, int width,
-    int height, int stride);
+    int height);
 
 #ifdef __cplusplus
 }  // extern "C"