libwebp: update to 0.4.3

This commit imports libwebp 0.4.3, including AUTHORS, COPYING, ChangeLog,
NEWS, PATENTS, README and src directories. In src, only includes header
and source files.

The patches required to build it in Qt will follow in separate
commit(s).

Change-Id: I23ebfd69e47a468c91a9e9b109e9cb8ac63705d4
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Reviewed-by: aavit <eirik.aavitsland@theqtcompany.com>

1 files changed, 45 insertions, 23 deletions

diff --git a/src/3rdparty/libwebp/src/webp/encode.h b/src/3rdparty/libwebp/src/webp/encode.h
index 7a428b4..b3f05b1 100644
--- a/src/3rdparty/libwebp/src/webp/encode.h
+++ b/src/3rdparty/libwebp/src/webp/encode.h
@@ -167,6 +167,16 @@ static WEBP_INLINE int WebPConfigPreset(WebPConfig* config,
                                 WEBP_ENCODER_ABI_VERSION);
 }
 
+#if WEBP_ENCODER_ABI_VERSION > 0x0202
+// Activate the lossless compression mode with the desired efficiency level
+// between 0 (fastest, lowest compression) and 9 (slower, best compression).
+// A good default level is '6', providing a fair tradeoff between compression
+// speed and final compressed size.
+// This function will overwrite several fields from config: 'method', 'quality'
+// and 'lossless'. Returns false in case of parameter error.
+WEBP_EXTERN(int) WebPConfigLosslessPreset(WebPConfig* config, int level);
+#endif
+
 // Returns true if 'config' is non-NULL and all configuration parameters are
 // within their valid ranges.
 WEBP_EXTERN(int) WebPValidateConfig(const WebPConfig* config);
@@ -221,9 +231,18 @@ struct WebPMemoryWriter {
 // The following must be called first before any use.
 WEBP_EXTERN(void) WebPMemoryWriterInit(WebPMemoryWriter* writer);
 
+#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.
-// writer.mem must be freed using the call 'free(writer.mem)'.
+#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);
 
@@ -235,16 +254,9 @@ typedef int (*WebPProgressHook)(int percent, const WebPPicture* picture);
 // Color spaces.
 typedef enum WebPEncCSP {
   // chroma sampling
-  WEBP_YUV420 = 0,   // 4:2:0
-  WEBP_YUV422 = 1,   // 4:2:2
-  WEBP_YUV444 = 2,   // 4:4:4
-  WEBP_YUV400 = 3,   // grayscale
-  WEBP_CSP_UV_MASK = 3,   // bit-mask to get the UV sampling factors
-  // alpha channel variants
-  WEBP_YUV420A = 4,
-  WEBP_YUV422A = 5,
-  WEBP_YUV444A = 6,
-  WEBP_YUV400A = 7,   // grayscale + alpha
+  WEBP_YUV420  = 0,        // 4:2:0
+  WEBP_YUV420A = 4,        // alpha channel variant
+  WEBP_CSP_UV_MASK = 3,    // bit-mask to get the UV sampling factors
   WEBP_CSP_ALPHA_BIT = 4   // bit that is set if alpha is present
 } WebPEncCSP;
 
@@ -323,17 +335,15 @@ struct WebPPicture {
 
   uint32_t pad3[3];       // padding for later use
 
-  // Unused for now: original samples (for non-YUV420 modes)
-  uint8_t *u0, *v0;
-  int uv0_stride;
-
-  uint32_t pad4[7];       // padding for later use
+  // Unused for now
+  uint8_t *pad4, *pad5;
+  uint32_t pad6[8];       // padding for later use
 
   // PRIVATE FIELDS
   ////////////////////
   void* memory_;          // row chunk of memory for yuva planes
   void* memory_argb_;     // and for argb too.
-  void* pad5[2];          // padding for later use
+  void* pad7[2];          // padding for later use
 };
 
 // Internal, version-checked, entry point
@@ -409,7 +419,9 @@ WEBP_EXTERN(int) WebPPictureView(const WebPPicture* src,
 WEBP_EXTERN(int) WebPPictureIsView(const WebPPicture* picture);
 
 // Rescale a picture to new dimension width x height.
-// Now gamma correction is applied.
+// If either 'width' or 'height' (but not both) is 0 the corresponding
+// dimension will be calculated preserving the aspect ratio.
+// No gamma correction is applied.
 // Returns false in case of error (invalid parameter or insufficient memory).
 WEBP_EXTERN(int) WebPPictureRescale(WebPPicture* pic, int width, int height);
 
@@ -436,13 +448,14 @@ WEBP_EXTERN(int) WebPPictureImportBGRA(
 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
@@ -451,6 +464,15 @@ WEBP_EXTERN(int) WebPPictureARGBToYUVA(WebPPicture* 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
@@ -459,9 +481,9 @@ WEBP_EXTERN(int) WebPPictureARGBToYUVADithered(
 // Returns false in case of error.
 WEBP_EXTERN(int) WebPPictureYUVAToARGB(WebPPicture* picture);
 
-// Helper function: given a width x height plane of YUV(A) samples
-// (with stride 'stride'), clean-up the YUV samples under fully transparent
-// area, to help compressibility (no guarantee, though).
+// 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
+// compressibility (no guarantee, though).
 WEBP_EXTERN(void) WebPCleanupTransparentArea(WebPPicture* picture);
 
 // Scan the picture 'picture' for the presence of non fully opaque alpha values.