Merge pull request #5592 from volzhs/libwebp-0.5.1

Update webp driver to 0.5.1

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/webp/enc/histogram.h b/drivers/webp/enc/histogram.h
index 72f045793a..59de42b33e 100644
--- a/drivers/webp/enc/histogram.h
+++ b/drivers/webp/enc/histogram.h
@@ -24,6 +24,9 @@
 extern "C" {
 #endif
 
+// Not a trivial literal symbol.
+#define VP8L_NON_TRIVIAL_SYM (0xffffffff)
+
 // A simple container for histograms of data.
 typedef struct {
   // literal_ contains green literal, palette-code and
@@ -103,6 +106,16 @@ int VP8LGetHistoImageSymbols(int xsize, int ysize,
                              VP8LHistogramSet* const tmp_histos,
                              uint16_t* const histogram_symbols);
 
+// Returns the entropy for the symbols in the input array.
+// Also sets trivial_symbol to the code value, if the array has only one code
+// value. Otherwise, set it to VP8L_NON_TRIVIAL_SYM.
+double VP8LBitsEntropy(const uint32_t* const array, int n,
+                       uint32_t* const trivial_symbol);
+
+// Estimate how many bits the combined entropy of literals and distance
+// approximately maps to.
+double VP8LHistogramEstimateBits(const VP8LHistogram* const p);
+
 #ifdef __cplusplus
 }
 #endif