libwebp: update to 0.4.2-rc2

third_party/libwebp/webp/encode.h

 // 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.
 // -----------------------------------------------------------------------------
 //
 //   WebP encoder: main interface
@@ skipping 213 matching lines @@
 struct WebPMemoryWriter {
   uint8_t* mem;       // final buffer (of size 'max_size', larger than 'size').
   size_t   size;      // final size
   size_t   max_size;  // total capacity
   uint32_t pad[1];    // padding for later use
 };
 
 // The following must be called first before any use.
 WEBP_EXTERN(void) WebPMemoryWriterInit(WebPMemoryWriter* writer);
 
-#if WEBP_ENCODER_ABI_VERSION > 0x0202
+#if WEBP_ENCODER_ABI_VERSION > 0x0203
 // The following must be called to deallocate writer->mem memory. The 'writer'
 // object itself is not deallocated.
 WEBP_EXTERN(void) WebPMemoryWriterClear(WebPMemoryWriter* writer);
 #endif
 // The custom writer to be used with WebPMemoryWriter as custom_ptr. Upon
 // completion, writer.mem and writer.size will hold the coded data.
-#if WEBP_ENCODER_ABI_VERSION > 0x0202
+#if WEBP_ENCODER_ABI_VERSION > 0x0203
 // writer.mem must be freed by calling WebPMemoryWriterClear.
 #else
 // writer.mem must be freed by calling 'free(writer.mem)'.
 #endif
 WEBP_EXTERN(int) WebPMemoryWrite(const uint8_t* data, size_t data_size,
                                  const WebPPicture* picture);
 
 // Progress hook, called from time to time to report progress. It can return
 // false to request an abort of the encoding process, or true otherwise if
 // everything is OK.
@@ skipping 187 matching lines @@
     WebPPicture* picture, const uint8_t* rgbx, int rgbx_stride);
 
 // Variants of the above, but taking BGR(A|X) input.
 WEBP_EXTERN(int) WebPPictureImportBGR(
     WebPPicture* picture, const uint8_t* bgr, int bgr_stride);
 WEBP_EXTERN(int) WebPPictureImportBGRA(
     WebPPicture* picture, const uint8_t* bgra, int bgra_stride);
 WEBP_EXTERN(int) WebPPictureImportBGRX(
     WebPPicture* picture, const uint8_t* bgrx, int bgrx_stride);
 
-// Converts picture->argb data to the YUVA format specified by 'colorspace'.
+// Converts picture->argb data to the YUV420A format. The 'colorspace'
+// parameter is deprecated and should be equal to WEBP_YUV420.
 // Upon return, picture->use_argb is set to false. The presence of real
 // non-opaque transparent values is detected, and 'colorspace' will be
 // adjusted accordingly. Note that this method is lossy.
 // Returns false in case of error.
 WEBP_EXTERN(int) WebPPictureARGBToYUVA(WebPPicture* picture,
-                                       WebPEncCSP colorspace);
+                                       WebPEncCSP /*colorspace = WEBP_YUV420*/);
 
 // Same as WebPPictureARGBToYUVA(), but the conversion is done using
 // pseudo-random dithering with a strength 'dithering' between
 // 0.0 (no dithering) and 1.0 (maximum dithering). This is useful
 // for photographic picture.
 WEBP_EXTERN(int) WebPPictureARGBToYUVADithered(
     WebPPicture* picture, WebPEncCSP colorspace, float dithering);
 
+#if WEBP_ENCODER_ABI_VERSION > 0x0204
+// Performs 'smart' RGBA->YUVA420 downsampling and colorspace conversion.
+// Downsampling is handled with extra care in case of color clipping. This
+// method is roughly 2x slower than WebPPictureARGBToYUVA() but produces better
+// YUV representation.
+// Returns false in case of error.
+WEBP_EXTERN(int) WebPPictureSmartARGBToYUVA(WebPPicture* picture);
+#endif
+
 // Converts picture->yuv to picture->argb and sets picture->use_argb to true.
 // The input format must be YUV_420 or YUV_420A.
 // Note that the use of this method is discouraged if one has access to the
 // raw ARGB samples, since using YUV420 is comparatively lossy. Also, the
 // conversion from YUV420 to ARGB incurs a small loss too.
 // Returns false in case of error.
 WEBP_EXTERN(int) WebPPictureYUVAToARGB(WebPPicture* picture);
 
 // Helper function: given a width x height plane of RGBA or YUV(A) samples
 // clean-up the YUV or RGB samples under fully transparent area, to help
@@ skipping 25 matching lines @@
 // another is provided but they both incur some loss.
 WEBP_EXTERN(int) WebPEncode(const WebPConfig* config, WebPPicture* picture);
 
 //------------------------------------------------------------------------------
 
 #ifdef __cplusplus
 }    // extern "C"
 #endif
 
 #endif  /* WEBP_WEBP_ENCODE_H_ */