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+// Copyright 2011 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.
+// -----------------------------------------------------------------------------
+//
+// Cost tables for level and modes.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#ifndef WEBP_ENC_COST_H_
+#define WEBP_ENC_COST_H_
+
+#include <assert.h>
+#include <stdlib.h>
+#include "./vp8i_enc.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// On-the-fly info about the current set of residuals. Handy to avoid
+// passing zillions of params.
+typedef struct VP8Residual VP8Residual;
+struct VP8Residual {
+ int first;
+ int last;
+ const int16_t* coeffs;
+
+ int coeff_type;
+ ProbaArray* prob;
+ StatsArray* stats;
+ CostArrayPtr costs;
+};
+
+void VP8InitResidual(int first, int coeff_type,
+ VP8Encoder* const enc, VP8Residual* const res);
+
+int VP8RecordCoeffs(int ctx, const VP8Residual* const res);
+
+// Record proba context used.
+static WEBP_INLINE int VP8RecordStats(int bit, proba_t* const stats) {
+ proba_t p = *stats;
+ // An overflow is inbound. Note we handle this at 0xfffe0000u instead of
+ // 0xffff0000u to make sure p + 1u does not overflow.
+ if (p >= 0xfffe0000u) {
+ p = ((p + 1u) >> 1) & 0x7fff7fffu; // -> divide the stats by 2.
+ }
+ // record bit count (lower 16 bits) and increment total count (upper 16 bits).
+ p += 0x00010000u + bit;
+ *stats = p;
+ return bit;
+}
+
+// Cost of coding one event with probability 'proba'.
+static WEBP_INLINE int VP8BitCost(int bit, uint8_t proba) {
+ return !bit ? VP8EntropyCost[proba] : VP8EntropyCost[255 - proba];
+}
+
+// Level cost calculations
+extern const uint16_t VP8LevelCodes[MAX_VARIABLE_LEVEL][2];
+void VP8CalculateLevelCosts(VP8EncProba* const proba);
+static WEBP_INLINE int VP8LevelCost(const uint16_t* const table, int level) {
+ return VP8LevelFixedCosts[level]
+ + table[(level > MAX_VARIABLE_LEVEL) ? MAX_VARIABLE_LEVEL : level];
+}
+
+// Mode costs
+extern const uint16_t VP8FixedCostsUV[4];
+extern const uint16_t VP8FixedCostsI16[4];
+extern const uint16_t VP8FixedCostsI4[NUM_BMODES][NUM_BMODES][NUM_BMODES];
+
+//------------------------------------------------------------------------------
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif /* WEBP_ENC_COST_H_ */