libwebp: update to 0.5.0

third_party/libwebp/enc/backward_references.h

 // Copyright 2012 Google Inc. All Rights Reserved.
 //
 // Use of this source code is governed by a BSD-style license
 // that can be found in the COPYING file in the root of the source
 // tree. An additional intellectual property rights grant can be found
 // in the file PATENTS. All contributing project authors may
 // be found in the AUTHORS file in the root of the source tree.
 // -----------------------------------------------------------------------------
 //
 // Author: Jyrki Alakuijala (jyrki@google.com)
 //
 
 #ifndef WEBP_ENC_BACKWARD_REFERENCES_H_
 #define WEBP_ENC_BACKWARD_REFERENCES_H_
 
 #include <assert.h>
 #include <stdlib.h>
 #include "../webp/types.h"
 #include "../webp/format_constants.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-// The spec allows 11, we use 9 bits to reduce memory consumption in encoding.
-// Having 9 instead of 11 only removes about 0.25 % of compression density.
-#define MAX_COLOR_CACHE_BITS 9
-
-// Max ever number of codes we'll use:
-#define PIX_OR_COPY_CODES_MAX \
-    (NUM_LITERAL_CODES + NUM_LENGTH_CODES + (1 << MAX_COLOR_CACHE_BITS))
+// The maximum allowed limit is 11.
+#define MAX_COLOR_CACHE_BITS 10
 
 // -----------------------------------------------------------------------------
 // PixOrCopy
 
 enum Mode {
   kLiteral,
   kCacheIdx,
   kCopy,
   kNone
 };
@@ skipping 141 matching lines @@
 static WEBP_INLINE void VP8LRefsCursorNext(VP8LRefsCursor* const c) {
   assert(c != NULL);
   assert(VP8LRefsCursorOk(c));
   if (++c->cur_pos == c->last_pos_) VP8LRefsCursorNextBlock(c);
 }
 
 // -----------------------------------------------------------------------------
 // Main entry points
 
 // Evaluates best possible backward references for specified quality.
-// Further optimize for 2D locality if use_2d_locality flag is set.
+// The input cache_bits to 'VP8LGetBackwardReferences' sets the maximum cache
+// bits to use (passing 0 implies disabling the local color cache).
+// The optimal cache bits is evaluated and set for the *cache_bits parameter.
 // The return value is the pointer to the best of the two backward refs viz,
 // refs[0] or refs[1].
 VP8LBackwardRefs* VP8LGetBackwardReferences(
     int width, int height, const uint32_t* const argb, int quality,
-    int cache_bits, int use_2d_locality, VP8LHashChain* const hash_chain,
+    int low_effort, int* const cache_bits, VP8LHashChain* const hash_chain,
     VP8LBackwardRefs refs[2]);
 
-// Produce an estimate for a good color cache size for the image.
-int VP8LCalculateEstimateForCacheSize(const uint32_t* const argb,
-                                      int xsize, int ysize, int quality,
-                                      VP8LHashChain* const hash_chain,
-                                      VP8LBackwardRefs* const ref,
-                                      int* const best_cache_bits);
-
 #ifdef __cplusplus
 }
 #endif
 
 #endif  // WEBP_ENC_BACKWARD_REFERENCES_H_