1 files changed, 41 insertions, 46 deletions

diff --git a/drivers/webp/enc/histogram.h b/drivers/webp/enc/histogram.h
index 5b5de25539..72f045793a 100644
--- a/drivers/webp/enc/histogram.h
+++ b/drivers/webp/enc/histogram.h
@@ -1,8 +1,10 @@
 // Copyright 2012 Google Inc. All Rights Reserved.
 //
-// This code is licensed under the same terms as WebM:
-//  Software License Agreement:  http://www.webmproject.org/license/software/
-//  Additional IP Rights Grant:  http://www.webmproject.org/license/additional/
+// 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)
@@ -12,17 +14,13 @@
 #ifndef WEBP_ENC_HISTOGRAM_H_
 #define WEBP_ENC_HISTOGRAM_H_
 
-#include <assert.h>
-#include <stddef.h>
-#include <stdlib.h>
-#include <stdio.h>
 #include <string.h>
 
 #include "./backward_references.h"
-#include "../format_constants.h"
-#include "../types.h"
+#include "webp/format_constants.h"
+#include "webp/types.h"
 
-#if defined(__cplusplus) || defined(c_plusplus)
+#ifdef __cplusplus
 extern "C" {
 #endif
 
@@ -30,18 +28,23 @@ extern "C" {
 typedef struct {
   // literal_ contains green literal, palette-code and
   // copy-length-prefix histogram
-  int literal_[PIX_OR_COPY_CODES_MAX];
-  int red_[256];
-  int blue_[256];
-  int alpha_[256];
+  uint32_t* literal_;         // Pointer to the allocated buffer for literal.
+  uint32_t red_[NUM_LITERAL_CODES];
+  uint32_t blue_[NUM_LITERAL_CODES];
+  uint32_t alpha_[NUM_LITERAL_CODES];
   // Backward reference prefix-code histogram.
-  int distance_[NUM_DISTANCE_CODES];
+  uint32_t distance_[NUM_DISTANCE_CODES];
   int palette_code_bits_;
-  double bit_cost_;   // cached value of VP8LHistogramEstimateBits(this)
+  uint32_t trivial_symbol_;  // True, if histograms for Red, Blue & Alpha
+                             // literal symbols are single valued.
+  double bit_cost_;          // cached value of bit cost.
+  double literal_cost_;      // Cached values of dominant entropy costs:
+  double red_cost_;          // literal, red & blue.
+  double blue_cost_;
 } VP8LHistogram;
 
 // Collection of histograms with fixed capacity, allocated as one
-// big memory chunk. Can be destroyed by simply calling 'free()'.
+// big memory chunk. Can be destroyed by calling WebPSafeFree().
 typedef struct {
   int size;         // number of slots currently in use
   int max_size;     // maximum capacity
@@ -57,6 +60,9 @@ void VP8LHistogramCreate(VP8LHistogram* const p,
                          const VP8LBackwardRefs* const refs,
                          int palette_code_bits);
 
+// Return the size of the histogram for a given palette_code_bits.
+int VP8LGetHistogramSize(int palette_code_bits);
+
 // Set the palette_code_bits and reset the stats.
 void VP8LHistogramInit(VP8LHistogram* const p, int palette_code_bits);
 
@@ -64,51 +70,40 @@ void VP8LHistogramInit(VP8LHistogram* const p, int palette_code_bits);
 void VP8LHistogramStoreRefs(const VP8LBackwardRefs* const refs,
                             VP8LHistogram* const histo);
 
+// Free the memory allocated for the histogram.
+void VP8LFreeHistogram(VP8LHistogram* const histo);
+
+// Free the memory allocated for the histogram set.
+void VP8LFreeHistogramSet(VP8LHistogramSet* const histo);
+
 // Allocate an array of pointer to histograms, allocated and initialized
 // using 'cache_bits'. Return NULL in case of memory error.
 VP8LHistogramSet* VP8LAllocateHistogramSet(int size, int cache_bits);
 
+// Allocate and initialize histogram object with specified 'cache_bits'.
+// Returns NULL in case of memory error.
+// Special case of VP8LAllocateHistogramSet, with size equals 1.
+VP8LHistogram* VP8LAllocateHistogram(int cache_bits);
+
 // Accumulate a token 'v' into a histogram.
 void VP8LHistogramAddSinglePixOrCopy(VP8LHistogram* const histo,
                                      const PixOrCopy* const v);
 
-// Estimate how many bits the combined entropy of literals and distance
-// approximately maps to.
-double VP8LHistogramEstimateBits(const VP8LHistogram* const p);
-
-// This function estimates the cost in bits excluding the bits needed to
-// represent the entropy code itself.
-double VP8LHistogramEstimateBitsBulk(const VP8LHistogram* const p);
-
-static WEBP_INLINE void VP8LHistogramAdd(VP8LHistogram* const p,
-                                         const VP8LHistogram* const a) {
-  int i;
-  for (i = 0; i < PIX_OR_COPY_CODES_MAX; ++i) {
-    p->literal_[i] += a->literal_[i];
-  }
-  for (i = 0; i < NUM_DISTANCE_CODES; ++i) {
-    p->distance_[i] += a->distance_[i];
-  }
-  for (i = 0; i < 256; ++i) {
-    p->red_[i] += a->red_[i];
-    p->blue_[i] += a->blue_[i];
-    p->alpha_[i] += a->alpha_[i];
-  }
-}
-
-static WEBP_INLINE int VP8LHistogramNumCodes(const VP8LHistogram* const p) {
-  return 256 + NUM_LENGTH_CODES +
-      ((p->palette_code_bits_ > 0) ? (1 << p->palette_code_bits_) : 0);
+static WEBP_INLINE int VP8LHistogramNumCodes(int palette_code_bits) {
+  return NUM_LITERAL_CODES + NUM_LENGTH_CODES +
+      ((palette_code_bits > 0) ? (1 << palette_code_bits) : 0);
 }
 
 // Builds the histogram image.
 int VP8LGetHistoImageSymbols(int xsize, int ysize,
                              const VP8LBackwardRefs* const refs,
-                             int quality, int histogram_bits, int cache_bits,
+                             int quality, int low_effort,
+                             int histogram_bits, int cache_bits,
                              VP8LHistogramSet* const image_in,
+                             VP8LHistogramSet* const tmp_histos,
                              uint16_t* const histogram_symbols);
 
-#if defined(__cplusplus) || defined(c_plusplus)
+#ifdef __cplusplus
 }
 #endif