diff --git a/src/enc/vp8l.c b/src/enc/vp8l.c
index 5efbe376..a1ac9860 100644
--- a/src/enc/vp8l.c
+++ b/src/enc/vp8l.c
@@ -28,8 +28,6 @@ extern "C" {
 
 #define PALETTE_KEY_RIGHT_SHIFT   22  // Key for 1K buffer.
 #define MAX_HUFF_IMAGE_SIZE       (16 * 1024 * 1024)
-#define MIN_HISTO_BITS            2
-#define MAX_HISTO_BITS            9
 
 // -----------------------------------------------------------------------------
 // Palette
@@ -517,7 +515,8 @@ static int EncodeImageInternal(VP8LBitWriter* const bw,
   VP8LBackwardRefs refs;
   uint16_t* const histogram_symbols =
       (uint16_t*)malloc(histogram_image_xysize * sizeof(*histogram_symbols));
-  assert(histogram_bits >= MIN_HISTO_BITS && histogram_bits <= MAX_HISTO_BITS);
+  assert(histogram_bits >= MIN_HUFFMAN_BITS);
+  assert(histogram_bits <= MAX_HUFFMAN_BITS);
   if (histogram_image == NULL || histogram_symbols == NULL) goto Error;
 
   // Calculate backward references from ARGB image.
@@ -894,8 +893,8 @@ static int GetHistoBits(const WebPConfig* const config,
     if (huff_image_size <= MAX_HUFF_IMAGE_SIZE) break;
     ++histo_bits;
   }
-  return (histo_bits < MIN_HISTO_BITS) ? MIN_HISTO_BITS :
-      (histo_bits > MAX_HISTO_BITS) ? MAX_HISTO_BITS : histo_bits;
+  return (histo_bits < MIN_HUFFMAN_BITS) ? MIN_HUFFMAN_BITS :
+         (histo_bits > MAX_HUFFMAN_BITS) ? MAX_HUFFMAN_BITS : histo_bits;
 }
 
 static void InitEncParams(VP8LEncoder* const enc) {
diff --git a/src/webp/format_constants.h b/src/webp/format_constants.h
index 5eb0feec..7ce498f6 100644
--- a/src/webp/format_constants.h
+++ b/src/webp/format_constants.h
@@ -40,6 +40,9 @@
 #define NUM_DISTANCE_CODES           40
 #define CODE_LENGTH_CODES            19
 
+#define MIN_HUFFMAN_BITS             2  // min number of Huffman bits
+#define MAX_HUFFMAN_BITS             9  // max number of Huffman bits
+
 #define TRANSFORM_PRESENT            1  // The bit to be written when next data
                                         // to be read is a transform.
 #define NUM_TRANSFORMS               4  // Maximum number of allowed transform