diff --git a/src/dsp/lossless_enc.c b/src/dsp/lossless_enc.c
index de6c4ace..9ac2e443 100644
--- a/src/dsp/lossless_enc.c
+++ b/src/dsp/lossless_enc.c
@@ -522,11 +522,11 @@ static void GetCombinedEntropyUnrefined_C(const uint32_t X[],
 void VP8LSubtractGreenFromBlueAndRed_C(uint32_t* argb_data, int num_pixels) {
   int i;
   for (i = 0; i < num_pixels; ++i) {
-    const int argb = argb_data[i];
+    const int argb = (int)argb_data[i];
     const int green = (argb >> 8) & 0xff;
     const uint32_t new_r = (((argb >> 16) & 0xff) - green) & 0xff;
     const uint32_t new_b = (((argb >>  0) & 0xff) - green) & 0xff;
-    argb_data[i] = (argb & 0xff00ff00u) | (new_r << 16) | new_b;
+    argb_data[i] = ((uint32_t)argb & 0xff00ff00u) | (new_r << 16) | new_b;
   }
 }