Add basic WebP format support.

- decode/encode
- partial build (platform/unix)

CMakeLists.txt

@@ -652,6 +652,8 @@ set(LOVE_SRC_MODULE_IMAGE_MAGPIE
 	src/modules/image/magpie/PKMHandler.h
 	src/modules/image/magpie/PNGHandler.cpp
 	src/modules/image/magpie/PNGHandler.h
+	src/modules/image/magpie/WEBPHandler.cpp
+	src/modules/image/magpie/WEBPHandler.h
 	src/modules/image/magpie/PVRHandler.cpp
 	src/modules/image/magpie/PVRHandler.h
 	src/modules/image/magpie/STBHandler.cpp

platform/unix/configure.ac

@@ -77,6 +77,7 @@ AS_VAR_IF([enable_gme], [yes], [ACLOVE_DEP_GME], [])
 AS_VAR_IF([enable_mpg123], [no],
 	  AC_DEFINE([LOVE_NOMPG123], [], [Build without mpg123]),
 	  [ACLOVE_DEP_MPG123])
+AS_VAR_IF([enable_module_image], [yes], [ACLOVE_DEP_WEBP], [])
 
 # Add flags for optional libraries
 AC_ARG_ENABLE([library-enet], [  --disable-library-enet    Turn off library enet], [], [enable_library_enet=yes])

platform/unix/deps.m4

@@ -27,6 +27,9 @@ AC_DEFUN([ACLOVE_DEP_SDL2], [
 AC_DEFUN([ACLOVE_DEP_PTHREAD], [
 	AC_SEARCH_LIBS([pthread_create], [pthread], [], [LOVE_MSG_ERROR([the POSIX threads library])])])
 
+AC_DEFUN([ACLOVE_DEP_WEBP], [
+	AC_SEARCH_LIBS([WebPDecodeRGBA], [webp], [], [LOVE_MSG_ERROR([WebP])])])
+
 # does not use pkg-config because of the FILE_OFFSET_BITS.. bit
 AC_DEFUN([ACLOVE_DEP_MPG123], [
 	AC_SEARCH_LIBS([mpg123_open_feed], [mpg123], [],

src/modules/image/FormatHandler.h

@@ -43,6 +43,7 @@ class FormatHandler : public love::Object
 	{
 		ENCODED_TGA,
 		ENCODED_PNG,
+		ENCODED_WEBP,
 		ENCODED_MAX_ENUM
 	};
 

src/modules/image/Image.cpp

@@ -23,6 +23,7 @@
 #include "common/config.h"
 
 #include "magpie/PNGHandler.h"
+#include "magpie/WEBPHandler.h"
 #include "magpie/STBHandler.h"
 #include "magpie/EXRHandler.h"
 
@@ -47,6 +48,7 @@ Image::Image()
 
 	formatHandlers = {
 		new PNGHandler,
+		new WEBPHandler,
 		new STBHandler,
 		new EXRHandler,
 		new DDSHandler,

src/modules/image/ImageData.cpp

@@ -897,6 +897,7 @@ StringMap<FormatHandler::EncodedFormat, FormatHandler::ENCODED_MAX_ENUM>::Entry
 {
 	{"tga", FormatHandler::ENCODED_TGA},
 	{"png", FormatHandler::ENCODED_PNG},
+	{"webp", FormatHandler::ENCODED_WEBP}
 };
 
 StringMap<FormatHandler::EncodedFormat, FormatHandler::ENCODED_MAX_ENUM> ImageData::encodedFormats(ImageData::encodedFormatEntries, sizeof(ImageData::encodedFormatEntries));

src/modules/image/magpie/WEBPHandler.cpp

@@ -0,0 +1,100 @@
+/**
+ * Copyright (c) 2006-2020 LOVE Development Team
+ *
+ * This software is provided 'as-is', without any express or implied
+ * warranty.  In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ *
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ *
+ * 1. The origin of this software must not be misrepresented; you must not
+ *    claim that you wrote the original software. If you use this software
+ *    in a product, an acknowledgment in the product documentation would be
+ *    appreciated but is not required.
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ *    misrepresented as being the original software.
+ * 3. This notice may not be removed or altered from any source distribution.
+ **/
+
+#include "WEBPHandler.h"
+
+// LOVE
+#include "common/Exception.h"
+#include "common/math.h"
+
+// libwebp
+#include <webp/decode.h>
+#include <webp/encode.h>
+
+// C++
+
+// C
+#include <cstdlib>
+
+namespace love
+{
+namespace image
+{
+namespace magpie
+{
+
+bool WEBPHandler::canDecode(Data *data)
+{
+	WebPBitstreamFeatures features;
+	bool ok = (WebPGetFeatures((uint8_t*)data->getData(), data->getSize(), &features) == VP8_STATUS_OK);
+	return ok && features.width > 0 && features.height > 0;
+}
+
+bool WEBPHandler::canEncode(PixelFormat rawFormat, EncodedFormat encodedFormat)
+{
+	return encodedFormat == ENCODED_WEBP && rawFormat == PIXELFORMAT_RGBA8;
+}
+
+WEBPHandler::DecodedImage WEBPHandler::decode(Data *data)
+{
+	int width, height;
+	uint8_t *pdata = WebPDecodeRGBA((uint8_t*)data->getData(), data->getSize(), &width, &height); 
+
+	if(pdata){
+		DecodedImage img;
+		img.width = width;
+		img.height = height;
+		img.size = (size_t)width*height*4;
+		img.format = PIXELFORMAT_RGBA8;
+		img.data = pdata;
+		return img;
+	}
+	else
+		throw love::Exception("Could not decode WebP image");
+}
+
+FormatHandler::EncodedImage WEBPHandler::encode(const DecodedImage &img, EncodedFormat encodedFormat)
+{
+	if (!canEncode(img.format, encodedFormat))
+		throw love::Exception("WebP encoder cannot encode to non-WebP format.");
+
+	uint8_t *data = 0;
+  // export using lossless encoding
+	size_t size = WebPEncodeLosslessRGBA((uint8_t*)img.data, img.width, img.height, img.width*4, &data);
+	if(size > 0){
+		EncodedImage out_img;
+		out_img.size = size;
+		out_img.data = data;
+		return out_img;
+	}
+	else{
+		if(data) WebPFree(data); // doc ambiguity: data may need to be freed on error
+		throw love::Exception("Could not encode WebP image");
+	}
+}
+
+void WEBPHandler::freeRawPixels(unsigned char *mem)
+{
+	WebPFree(mem);
+}
+
+} // magpie
+} // image
+} // love

src/modules/image/magpie/WEBPHandler.h

@@ -0,0 +1,53 @@
+/**
+ * Copyright (c) 2006-2020 LOVE Development Team
+ *
+ * This software is provided 'as-is', without any express or implied
+ * warranty.  In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ *
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ *
+ * 1. The origin of this software must not be misrepresented; you must not
+ *    claim that you wrote the original software. If you use this software
+ *    in a product, an acknowledgment in the product documentation would be
+ *    appreciated but is not required.
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ *    misrepresented as being the original software.
+ * 3. This notice may not be removed or altered from any source distribution.
+ **/
+
+#pragma once
+
+// LOVE
+#include "image/FormatHandler.h"
+
+namespace love
+{
+namespace image
+{
+namespace magpie
+{
+
+/**
+ * Interface between ImageData and libwebp.
+ **/
+class WEBPHandler : public FormatHandler
+{
+public:
+
+	// Implements FormatHandler.
+
+	virtual bool canDecode(Data *data);
+	virtual bool canEncode(PixelFormat rawFormat, EncodedFormat encodedFormat);
+
+	virtual DecodedImage decode(Data *data);
+	virtual EncodedImage encode(const DecodedImage &img, EncodedFormat format);
+
+	virtual void freeRawPixels(unsigned char *mem);
+}; // WEBPHandler
+
+} // magpie
+} // image
+} // love