Update libwebp to 0.4.0

third_party/libwebp/enc/vp8l.c

Index: third_party/libwebp/enc/vp8l.c
diff --git a/third_party/libwebp/enc/vp8l.c b/third_party/libwebp/enc/vp8l.c
index 945870ca46a59e61c14bda5493e88c7e01f28e5d..15726318e253c22e70c127cc4bf5f805204605f2 100644
--- a/third_party/libwebp/enc/vp8l.c
+++ b/third_party/libwebp/enc/vp8l.c
@@ -25,10 +25,6 @@
 #include "../utils/utils.h"
 #include "../webp/format_constants.h"
 
-#if defined(__cplusplus) || defined(c_plusplus)
-extern "C" {
-#endif
-
 #define PALETTE_KEY_RIGHT_SHIFT   22  // Key for 1K buffer.
 #define MAX_HUFF_IMAGE_SIZE       (16 * 1024 * 1024)
 #define MAX_COLORS_FOR_GRAPH      64
@@ -168,9 +164,6 @@ static int VP8LEncAnalyze(VP8LEncoder* const enc, WebPImageHint image_hint) {
       }
       if (pred_entropy < 0.95 * non_pred_entropy) {
         enc->use_predict_ = 1;
-        // TODO(vikasa): Observed some correlation of cross_color transform with
-        // predict. Need to investigate this further and add separate heuristic
-        // for setting use_cross_color flag.
         enc->use_cross_color_ = 1;
       }
     }
@@ -451,12 +444,12 @@ static void StoreImageToBitMask(
       int bits, n_bits;
       int code, distance;
 
-      PrefixEncode(v->len, &code, &n_bits, &bits);
+      VP8LPrefixEncode(v->len, &code, &n_bits, &bits);
       WriteHuffmanCode(bw, codes, 256 + code);
       VP8LWriteBits(bw, n_bits, bits);
 
       distance = PixOrCopyDistance(v);
-      PrefixEncode(distance, &code, &n_bits, &bits);
+      VP8LPrefixEncode(distance, &code, &n_bits, &bits);
       WriteHuffmanCode(bw, codes + 4, code);
       VP8LWriteBits(bw, n_bits, bits);
     }
@@ -702,7 +695,7 @@ static int ApplyCrossColorFilter(const VP8LEncoder* const enc,
   const int ccolor_transform_bits = enc->transform_bits_;
   const int transform_width = VP8LSubSampleSize(width, ccolor_transform_bits);
   const int transform_height = VP8LSubSampleSize(height, ccolor_transform_bits);
-  const int step = (quality == 0) ? 32 : 8;
+  const int step = (quality < 25) ? 32 : (quality > 50) ? 8 : 16;
 
   VP8LColorSpaceTransform(width, height, ccolor_transform_bits, step,
                           enc->argb_, enc->transform_data_);
@@ -827,7 +820,7 @@ static void ApplyPalette(uint32_t* src, uint32_t* dst,
   }
 
   if (use_LUT) {
-    int inv_palette[MAX_PALETTE_SIZE] = { 0 };
+    uint8_t inv_palette[MAX_PALETTE_SIZE] = { 0 };
     for (i = 0; i < palette_size; ++i) {
       const int color = (palette[i] >> 8) & 0xff;
       inv_palette[color] = i;
@@ -895,7 +888,7 @@ static WebPEncodingError EncodePalette(VP8LBitWriter* const bw,
   if (err != VP8_ENC_OK) goto Error;
   dst = enc->argb_;
 
-  row = WebPSafeMalloc((uint64_t)width, sizeof(*row));
+  row = (uint8_t*)WebPSafeMalloc((uint64_t)width, sizeof(*row));
   if (row == NULL) return VP8_ENC_ERROR_OUT_OF_MEMORY;
 
   ApplyPalette(src, dst, pic->argb_stride, enc->current_width_,
@@ -959,6 +952,9 @@ static VP8LEncoder* VP8LEncoderNew(const WebPConfig* const config,
   }
   enc->config_ = config;
   enc->pic_ = picture;
+
+  VP8LDspInit();
+
   return enc;
 }
 
@@ -1170,6 +1166,3 @@ int VP8LEncodeImage(const WebPConfig* const config,
 
 //------------------------------------------------------------------------------
 
-#if defined(__cplusplus) || defined(c_plusplus)
-}    // extern "C"
-#endif