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diff --git a/thirdparty/libwebp/dsp/lossless.h b/thirdparty/libwebp/dsp/lossless.h
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+// 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.
+// -----------------------------------------------------------------------------
+//
+// Image transforms and color space conversion methods for lossless decoder.
+//
+// Authors: Vikas Arora (vikaas.arora@gmail.com)
+// Jyrki Alakuijala (jyrki@google.com)
+
+#ifndef WEBP_DSP_LOSSLESS_H_
+#define WEBP_DSP_LOSSLESS_H_
+
+#include "../webp/types.h"
+#include "../webp/decode.h"
+
+#include "../enc/histogram.h"
+#include "../utils/utils.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef WEBP_EXPERIMENTAL_FEATURES
+#include "../enc/delta_palettization.h"
+#endif // WEBP_EXPERIMENTAL_FEATURES
+
+//------------------------------------------------------------------------------
+// Decoding
+
+typedef uint32_t (*VP8LPredictorFunc)(uint32_t left, const uint32_t* const top);
+extern VP8LPredictorFunc VP8LPredictors[16];
+
+typedef void (*VP8LProcessBlueAndRedFunc)(uint32_t* argb_data, int num_pixels);
+extern VP8LProcessBlueAndRedFunc VP8LAddGreenToBlueAndRed;
+
+typedef struct {
+ // Note: the members are uint8_t, so that any negative values are
+ // automatically converted to "mod 256" values.
+ uint8_t green_to_red_;
+ uint8_t green_to_blue_;
+ uint8_t red_to_blue_;
+} VP8LMultipliers;
+typedef void (*VP8LTransformColorFunc)(const VP8LMultipliers* const m,
+ uint32_t* argb_data, int num_pixels);
+extern VP8LTransformColorFunc VP8LTransformColorInverse;
+
+struct VP8LTransform; // Defined in dec/vp8li.h.
+
+// Performs inverse transform of data given transform information, start and end
+// rows. Transform will be applied to rows [row_start, row_end[.
+// The *in and *out pointers refer to source and destination data respectively
+// corresponding to the intermediate row (row_start).
+void VP8LInverseTransform(const struct VP8LTransform* const transform,
+ int row_start, int row_end,
+ const uint32_t* const in, uint32_t* const out);
+
+// Color space conversion.
+typedef void (*VP8LConvertFunc)(const uint32_t* src, int num_pixels,
+ uint8_t* dst);
+extern VP8LConvertFunc VP8LConvertBGRAToRGB;
+extern VP8LConvertFunc VP8LConvertBGRAToRGBA;
+extern VP8LConvertFunc VP8LConvertBGRAToRGBA4444;
+extern VP8LConvertFunc VP8LConvertBGRAToRGB565;
+extern VP8LConvertFunc VP8LConvertBGRAToBGR;
+
+// Converts from BGRA to other color spaces.
+void VP8LConvertFromBGRA(const uint32_t* const in_data, int num_pixels,
+ WEBP_CSP_MODE out_colorspace, uint8_t* const rgba);
+
+// color mapping related functions.
+static WEBP_INLINE uint32_t VP8GetARGBIndex(uint32_t idx) {
+ return (idx >> 8) & 0xff;
+}
+
+static WEBP_INLINE uint8_t VP8GetAlphaIndex(uint8_t idx) {
+ return idx;
+}
+
+static WEBP_INLINE uint32_t VP8GetARGBValue(uint32_t val) {
+ return val;
+}
+
+static WEBP_INLINE uint8_t VP8GetAlphaValue(uint32_t val) {
+ return (val >> 8) & 0xff;
+}
+
+typedef void (*VP8LMapARGBFunc)(const uint32_t* src,
+ const uint32_t* const color_map,
+ uint32_t* dst, int y_start,
+ int y_end, int width);
+typedef void (*VP8LMapAlphaFunc)(const uint8_t* src,
+ const uint32_t* const color_map,
+ uint8_t* dst, int y_start,
+ int y_end, int width);
+
+extern VP8LMapARGBFunc VP8LMapColor32b;
+extern VP8LMapAlphaFunc VP8LMapColor8b;
+
+// Similar to the static method ColorIndexInverseTransform() that is part of
+// lossless.c, but used only for alpha decoding. It takes uint8_t (rather than
+// uint32_t) arguments for 'src' and 'dst'.
+void VP8LColorIndexInverseTransformAlpha(
+ const struct VP8LTransform* const transform, int y_start, int y_end,
+ const uint8_t* src, uint8_t* dst);
+
+// Expose some C-only fallback functions
+void VP8LTransformColorInverse_C(const VP8LMultipliers* const m,
+ uint32_t* data, int num_pixels);
+
+void VP8LConvertBGRAToRGB_C(const uint32_t* src, int num_pixels, uint8_t* dst);
+void VP8LConvertBGRAToRGBA_C(const uint32_t* src, int num_pixels, uint8_t* dst);
+void VP8LConvertBGRAToRGBA4444_C(const uint32_t* src,
+ int num_pixels, uint8_t* dst);
+void VP8LConvertBGRAToRGB565_C(const uint32_t* src,
+ int num_pixels, uint8_t* dst);
+void VP8LConvertBGRAToBGR_C(const uint32_t* src, int num_pixels, uint8_t* dst);
+void VP8LAddGreenToBlueAndRed_C(uint32_t* data, int num_pixels);
+
+// Must be called before calling any of the above methods.
+void VP8LDspInit(void);
+
+//------------------------------------------------------------------------------
+// Encoding
+
+extern VP8LProcessBlueAndRedFunc VP8LSubtractGreenFromBlueAndRed;
+extern VP8LTransformColorFunc VP8LTransformColor;
+typedef void (*VP8LCollectColorBlueTransformsFunc)(
+ const uint32_t* argb, int stride,
+ int tile_width, int tile_height,
+ int green_to_blue, int red_to_blue, int histo[]);
+extern VP8LCollectColorBlueTransformsFunc VP8LCollectColorBlueTransforms;
+
+typedef void (*VP8LCollectColorRedTransformsFunc)(
+ const uint32_t* argb, int stride,
+ int tile_width, int tile_height,
+ int green_to_red, int histo[]);
+extern VP8LCollectColorRedTransformsFunc VP8LCollectColorRedTransforms;
+
+// Expose some C-only fallback functions
+void VP8LTransformColor_C(const VP8LMultipliers* const m,
+ uint32_t* data, int num_pixels);
+void VP8LSubtractGreenFromBlueAndRed_C(uint32_t* argb_data, int num_pixels);
+void VP8LCollectColorRedTransforms_C(const uint32_t* argb, int stride,
+ int tile_width, int tile_height,
+ int green_to_red, int histo[]);
+void VP8LCollectColorBlueTransforms_C(const uint32_t* argb, int stride,
+ int tile_width, int tile_height,
+ int green_to_blue, int red_to_blue,
+ int histo[]);
+
+//------------------------------------------------------------------------------
+// Image transforms.
+
+void VP8LResidualImage(int width, int height, int bits, int low_effort,
+ uint32_t* const argb, uint32_t* const argb_scratch,
+ uint32_t* const image, int near_lossless, int exact,
+ int used_subtract_green);
+
+void VP8LColorSpaceTransform(int width, int height, int bits, int quality,
+ uint32_t* const argb, uint32_t* image);
+
+//------------------------------------------------------------------------------
+// Misc methods.
+
+// Computes sampled size of 'size' when sampling using 'sampling bits'.
+static WEBP_INLINE uint32_t VP8LSubSampleSize(uint32_t size,
+ uint32_t sampling_bits) {
+ return (size + (1 << sampling_bits) - 1) >> sampling_bits;
+}
+
+// Converts near lossless quality into max number of bits shaved off.
+static WEBP_INLINE int VP8LNearLosslessBits(int near_lossless_quality) {
+ // 100 -> 0
+ // 80..99 -> 1
+ // 60..79 -> 2
+ // 40..59 -> 3
+ // 20..39 -> 4
+ // 0..19 -> 5
+ return 5 - near_lossless_quality / 20;
+}
+
+// -----------------------------------------------------------------------------
+// Faster logarithm for integers. Small values use a look-up table.
+
+// The threshold till approximate version of log_2 can be used.
+// Practically, we can get rid of the call to log() as the two values match to
+// very high degree (the ratio of these two is 0.99999x).
+// Keeping a high threshold for now.
+#define APPROX_LOG_WITH_CORRECTION_MAX 65536
+#define APPROX_LOG_MAX 4096
+#define LOG_2_RECIPROCAL 1.44269504088896338700465094007086
+#define LOG_LOOKUP_IDX_MAX 256
+extern const float kLog2Table[LOG_LOOKUP_IDX_MAX];
+extern const float kSLog2Table[LOG_LOOKUP_IDX_MAX];
+typedef float (*VP8LFastLog2SlowFunc)(uint32_t v);
+
+extern VP8LFastLog2SlowFunc VP8LFastLog2Slow;
+extern VP8LFastLog2SlowFunc VP8LFastSLog2Slow;
+
+static WEBP_INLINE float VP8LFastLog2(uint32_t v) {
+ return (v < LOG_LOOKUP_IDX_MAX) ? kLog2Table[v] : VP8LFastLog2Slow(v);
+}
+// Fast calculation of v * log2(v) for integer input.
+static WEBP_INLINE float VP8LFastSLog2(uint32_t v) {
+ return (v < LOG_LOOKUP_IDX_MAX) ? kSLog2Table[v] : VP8LFastSLog2Slow(v);
+}
+
+// -----------------------------------------------------------------------------
+// Huffman-cost related functions.
+
+typedef double (*VP8LCostFunc)(const uint32_t* population, int length);
+typedef double (*VP8LCostCombinedFunc)(const uint32_t* X, const uint32_t* Y,
+ int length);
+typedef float (*VP8LCombinedShannonEntropyFunc)(const int X[256],
+ const int Y[256]);
+
+extern VP8LCostFunc VP8LExtraCost;
+extern VP8LCostCombinedFunc VP8LExtraCostCombined;
+extern VP8LCombinedShannonEntropyFunc VP8LCombinedShannonEntropy;
+
+typedef struct { // small struct to hold counters
+ int counts[2]; // index: 0=zero steak, 1=non-zero streak
+ int streaks[2][2]; // [zero/non-zero][streak<3 / streak>=3]
+} VP8LStreaks;
+
+typedef VP8LStreaks (*VP8LCostCombinedCountFunc)(const uint32_t* X,
+ const uint32_t* Y, int length);
+
+extern VP8LCostCombinedCountFunc VP8LHuffmanCostCombinedCount;
+
+typedef struct { // small struct to hold bit entropy results
+ double entropy; // entropy
+ uint32_t sum; // sum of the population
+ int nonzeros; // number of non-zero elements in the population
+ uint32_t max_val; // maximum value in the population
+ uint32_t nonzero_code; // index of the last non-zero in the population
+} VP8LBitEntropy;
+
+void VP8LBitEntropyInit(VP8LBitEntropy* const entropy);
+
+// Get the combined symbol bit entropy and Huffman cost stats for the
+// distributions 'X' and 'Y'. Those results can then be refined according to
+// codec specific heuristics.
+void VP8LGetCombinedEntropyUnrefined(const uint32_t* const X,
+ const uint32_t* const Y, int length,
+ VP8LBitEntropy* const bit_entropy,
+ VP8LStreaks* const stats);
+// Get the entropy for the distribution 'X'.
+void VP8LGetEntropyUnrefined(const uint32_t* const X, int length,
+ VP8LBitEntropy* const bit_entropy,
+ VP8LStreaks* const stats);
+
+void VP8LBitsEntropyUnrefined(const uint32_t* const array, int n,
+ VP8LBitEntropy* const entropy);
+
+typedef void (*GetEntropyUnrefinedHelperFunc)(uint32_t val, int i,
+ uint32_t* const val_prev,
+ int* const i_prev,
+ VP8LBitEntropy* const bit_entropy,
+ VP8LStreaks* const stats);
+// Internal function used by VP8LGet*EntropyUnrefined.
+extern GetEntropyUnrefinedHelperFunc VP8LGetEntropyUnrefinedHelper;
+
+typedef void (*VP8LHistogramAddFunc)(const VP8LHistogram* const a,
+ const VP8LHistogram* const b,
+ VP8LHistogram* const out);
+extern VP8LHistogramAddFunc VP8LHistogramAdd;
+
+// -----------------------------------------------------------------------------
+// PrefixEncode()
+
+typedef int (*VP8LVectorMismatchFunc)(const uint32_t* const array1,
+ const uint32_t* const array2, int length);
+// Returns the first index where array1 and array2 are different.
+extern VP8LVectorMismatchFunc VP8LVectorMismatch;
+
+static WEBP_INLINE int VP8LBitsLog2Ceiling(uint32_t n) {
+ const int log_floor = BitsLog2Floor(n);
+ if (n == (n & ~(n - 1))) // zero or a power of two.
+ return log_floor;
+ else
+ return log_floor + 1;
+}
+
+// Splitting of distance and length codes into prefixes and
+// extra bits. The prefixes are encoded with an entropy code
+// while the extra bits are stored just as normal bits.
+static WEBP_INLINE void VP8LPrefixEncodeBitsNoLUT(int distance, int* const code,
+ int* const extra_bits) {
+ const int highest_bit = BitsLog2Floor(--distance);
+ const int second_highest_bit = (distance >> (highest_bit - 1)) & 1;
+ *extra_bits = highest_bit - 1;
+ *code = 2 * highest_bit + second_highest_bit;
+}
+
+static WEBP_INLINE void VP8LPrefixEncodeNoLUT(int distance, int* const code,
+ int* const extra_bits,
+ int* const extra_bits_value) {
+ const int highest_bit = BitsLog2Floor(--distance);
+ const int second_highest_bit = (distance >> (highest_bit - 1)) & 1;
+ *extra_bits = highest_bit - 1;
+ *extra_bits_value = distance & ((1 << *extra_bits) - 1);
+ *code = 2 * highest_bit + second_highest_bit;
+}
+
+#define PREFIX_LOOKUP_IDX_MAX 512
+typedef struct {
+ int8_t code_;
+ int8_t extra_bits_;
+} VP8LPrefixCode;
+
+// These tables are derived using VP8LPrefixEncodeNoLUT.
+extern const VP8LPrefixCode kPrefixEncodeCode[PREFIX_LOOKUP_IDX_MAX];
+extern const uint8_t kPrefixEncodeExtraBitsValue[PREFIX_LOOKUP_IDX_MAX];
+static WEBP_INLINE void VP8LPrefixEncodeBits(int distance, int* const code,
+ int* const extra_bits) {
+ if (distance < PREFIX_LOOKUP_IDX_MAX) {
+ const VP8LPrefixCode prefix_code = kPrefixEncodeCode[distance];
+ *code = prefix_code.code_;
+ *extra_bits = prefix_code.extra_bits_;
+ } else {
+ VP8LPrefixEncodeBitsNoLUT(distance, code, extra_bits);
+ }
+}
+
+static WEBP_INLINE void VP8LPrefixEncode(int distance, int* const code,
+ int* const extra_bits,
+ int* const extra_bits_value) {
+ if (distance < PREFIX_LOOKUP_IDX_MAX) {
+ const VP8LPrefixCode prefix_code = kPrefixEncodeCode[distance];
+ *code = prefix_code.code_;
+ *extra_bits = prefix_code.extra_bits_;
+ *extra_bits_value = kPrefixEncodeExtraBitsValue[distance];
+ } else {
+ VP8LPrefixEncodeNoLUT(distance, code, extra_bits, extra_bits_value);
+ }
+}
+
+// Sum of each component, mod 256.
+static WEBP_INLINE uint32_t VP8LAddPixels(uint32_t a, uint32_t b) {
+ const uint32_t alpha_and_green = (a & 0xff00ff00u) + (b & 0xff00ff00u);
+ const uint32_t red_and_blue = (a & 0x00ff00ffu) + (b & 0x00ff00ffu);
+ return (alpha_and_green & 0xff00ff00u) | (red_and_blue & 0x00ff00ffu);
+}
+
+// Difference of each component, mod 256.
+static WEBP_INLINE uint32_t VP8LSubPixels(uint32_t a, uint32_t b) {
+ const uint32_t alpha_and_green =
+ 0x00ff00ffu + (a & 0xff00ff00u) - (b & 0xff00ff00u);
+ const uint32_t red_and_blue =
+ 0xff00ff00u + (a & 0x00ff00ffu) - (b & 0x00ff00ffu);
+ return (alpha_and_green & 0xff00ff00u) | (red_and_blue & 0x00ff00ffu);
+}
+
+void VP8LBundleColorMap(const uint8_t* const row, int width,
+ int xbits, uint32_t* const dst);
+
+// Must be called before calling any of the above methods.
+void VP8LEncDspInit(void);
+
+//------------------------------------------------------------------------------
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif // WEBP_DSP_LOSSLESS_H_
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