wrlib: Added support for webp image

This patch is adding support for google webp image format, if you
don't know it a quick recap is to say that according to their tests
they claim it is better than png and jpeg.

Follow the link below for some more details:
https://developers.google.com/speed/webp/

Signed-off-by: Carlos R. Mafra <crmafra@gmail.com>

configure.ac

@@ -679,6 +679,17 @@ AC_ARG_ENABLE([tiff],
 WM_IMGFMT_CHECK_TIFF
 
 
+dnl WEBP Support
+dnl ===========
+AC_ARG_ENABLE([webp],
+    [AS_HELP_STRING([--disable-webp], [disable WEBP support through libwebp])],
+    [AS_CASE(["$enableval"],
+        [yes|no], [],
+        [AC_MSG_ERROR([bad value $enableval for --enable-webp])] )],
+    [enable_webp=auto])
+WM_IMGFMT_CHECK_WEBP
+
+
 dnl PPM Support
 dnl ===========
 # The PPM format is always enabled because we have built-in support for the format

m4/wm_imgfmt_check.m4

@@ -174,6 +174,29 @@ AC_DEFUN_ONCE([WM_IMGFMT_CHECK_TIFF],
 ]) dnl AC_DEFUN
 
 
+# WM_IMGFMT_CHECK_WEBP
+# -------------------
+#
+# Check for WEBP file support through 'libwebp'
+# The check depends on variable 'enable_webp' being either:
+#   yes  - detect, fail if not found
+#   no   - do not detect, disable support
+#   auto - detect, disable if not found
+#
+# When found, append appropriate stuff in GFXLIBS, and append info to
+# the variable 'supported_gfx'
+# When not found, append info to variable 'unsupported'
+AC_DEFUN_ONCE([WM_IMGFMT_CHECK_WEBP],
+[WM_LIB_CHECK([WEBP], ["-lwebp"], [VP8DecodeLayer], [$XLFLAGS $XLIBS],
+    [wm_save_CFLAGS="$CFLAGS"
+     AS_IF([wm_fn_lib_try_compile "webp/decode.h" "" "return 0" ""],
+         [],
+         [AC_MSG_ERROR([found $CACHEVAR but could not find appropriate header - are you missing libwebp-dev package?])])
+     CFLAGS="$wm_save_CFLAGS"],
+    [supported_gfx], [GFXLIBS])dnl
+]) dnl AC_DEFUN
+
+
 # WM_IMGFMT_CHECK_XPM
 # -------------------
 #

wrlib/Makefile.am

@@ -60,6 +60,10 @@ else
 libwraster_la_SOURCES += load_xpm_normalized.c
 endif
 
+if USE_WEBP
+libwraster_la_SOURCES += load_webp.c
+endif
+
 AM_CPPFLAGS = $(DFLAGS) @HEADER_SEARCH_PATH@
 
 libwraster_la_LIBADD = @LIBRARY_SEARCH_PATH@ @GFXLIBS@ @XLIBS@ @LIBXMU@ -lm

wrlib/imgformat.h

@@ -38,12 +38,13 @@ typedef enum {
 	IM_PNG     =  3,
 	IM_PPM     =  4,
 	IM_JPEG    =  5,
-	IM_GIF     =  6
+	IM_GIF     =  6,
+	IM_WEBP    =  7
 } WRImgFormat;
 
 /* How many image types we have. */
 /* Increase this when adding new image types! */
-#define IM_TYPES    6
+#define IM_TYPES    7
 
 /*
  * Function for Loading in a specific format
@@ -68,6 +69,10 @@ RImage *RLoadJPEG(const char *file);
 RImage *RLoadGIF(const char *file, int index);
 #endif
 
+#ifdef USE_WEBP
+RImage *RLoadWEBP(const char *file);
+#endif
+
 /*
  * Function for Saving in a specific format
  */

wrlib/load.c

@@ -3,6 +3,7 @@
  * Raster graphics library
  *
  * Copyright (c) 1997-2003 Alfredo K. Kojima
+ * Copyright (c) 2014 Window Maker Team
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Library General Public
@@ -93,6 +94,9 @@ char **RSupportedFileFormats(void)
 #endif
 #ifdef USE_GIF
 	tmp[i++] = "GIF";
+#endif
+#ifdef USE_WEBP
+	tmp[i++] = "WEBP";
 #endif
 	tmp[i] = NULL;
 
@@ -192,6 +196,12 @@ RImage *RLoadImage(RContext * context, const char *file, int index)
 		break;
 #endif				/* USE_GIF */
 
+#ifdef USE_WEBP
+	case IM_WEBP:
+		image = RLoadWEBP(file);
+		break;
+#endif				/* USE_WEBP */
+
 	case IM_PPM:
 		image = RLoadPPM(file);
 		break;
@@ -266,6 +276,11 @@ char *RGetImageFileFormat(const char *file)
 		return "GIF";
 #endif				/* USE_GIF */
 
+#ifdef USE_WEBP
+	case IM_WEBP:
+		return "WEBP";
+#endif				/* USE_WEBP */
+
 	case IM_PPM:
 		return "PPM";
 
@@ -329,5 +344,14 @@ static WRImgFormat identFile(const char *path)
 	    (buffer[4] == '7' ||  buffer[4] == '9') && buffer[5] == 'a')
 		return IM_GIF;
 
+	/* check for WEBP */
+	if (buffer[ 0] == 'R' && buffer[ 1] == 'I' && buffer[ 2] == 'F' && buffer[ 3] == 'F' &&
+	    buffer[ 8] == 'W' && buffer[ 9] == 'E' && buffer[10] == 'B' && buffer[11] == 'P' &&
+	    buffer[12] == 'V' && buffer[13] == 'P' && buffer[14] == '8' &&
+	    (buffer[15] == ' '       /* Simple File Format (Lossy) */
+	     || buffer[15] == 'L'    /* Simple File Format (Lossless) */
+	     || buffer[15] == 'X'))  /* Extended File Format */
+		return IM_WEBP;
+
 	return IM_UNKNOWN;
 }

wrlib/load_webp.c

@@ -0,0 +1,138 @@
+/* load_webp.c - load WEBP image from file
+ *
+ * Raster graphics library
+ *
+ * Copyright (c) 2014 Window Maker Team
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Library General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Library General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Library General Public
+ *  License along with this library; if not, write to the Free
+ *  Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+ *  MA 02110-1301, USA.
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <webp/decode.h>
+
+#include "wraster.h"
+#include "imgformat.h"
+
+
+RImage *RLoadWEBP(const char *file_name)
+{
+	FILE *file;
+	RImage *image = NULL;
+	char buffer[20];
+	int raw_data_size;
+	int r;
+	uint8_t *raw_data;
+	WebPBitstreamFeatures features;
+	uint8_t *ret = NULL;
+
+	file = fopen(file_name, "rb");
+	if (!file) {
+		RErrorCode = RERR_OPEN;
+		return NULL;
+	}
+
+	if (!fread(buffer, sizeof(buffer), 1, file)) {
+		RErrorCode = RERR_BADIMAGEFILE;
+		fclose(file);
+		return NULL;
+	}
+
+	if (!(buffer[ 0] == 'R' && buffer[ 1] == 'I' && buffer[ 2] == 'F' && buffer[ 3] == 'F' &&
+	      buffer[ 8] == 'W' && buffer[ 9] == 'E' && buffer[10] == 'B' && buffer[11] == 'P' &&
+	      buffer[12] == 'V' && buffer[13] == 'P' && buffer[14] == '8' &&
+#if WEBP_DECODER_ABI_VERSION < 0x0003	/* old versions don't support WEBPVP8X and WEBPVP8L */
+	      buffer[15] == ' ')) {
+#else
+	      (buffer[15] == ' ' || buffer[15] == 'X' || buffer[15] == 'L'))) {
+#endif
+		RErrorCode = RERR_BADFORMAT;
+		fclose(file);
+		return NULL;
+	}
+
+	fseek(file, 0L, SEEK_END);
+	raw_data_size = ftell(file);
+
+	if (raw_data_size <= 0) {
+		fprintf(stderr, "wrlib: Failed to find the WEBP file size for \"%s\"\n", file_name);
+		RErrorCode = RERR_BADIMAGEFILE;
+		fclose(file);
+		return NULL;
+	}
+
+	raw_data = (uint8_t *) malloc(raw_data_size);
+
+	if (!raw_data) {
+		RErrorCode = RERR_NOMEMORY;
+		fclose(file);
+		return NULL;
+	}
+
+	fseek(file, 0L, SEEK_SET);
+	r = fread(raw_data, 1, raw_data_size, file);
+	fclose(file);
+
+	if (r != raw_data_size) {
+		RErrorCode = RERR_READ;
+		free(raw_data);
+		return NULL;
+	}
+
+	if (WebPGetFeatures(raw_data, raw_data_size, &features) != VP8_STATUS_OK) {
+		fprintf(stderr, "wrlib: WebPGetFeatures has failed on \"%s\"\n", file_name);
+		RErrorCode = RERR_BADIMAGEFILE;
+		free(raw_data);
+		return NULL;
+	}
+
+	if (features.has_alpha) {
+		image = RCreateImage(features.width, features.height, True);
+		if (!image) {
+			RErrorCode = RERR_NOMEMORY;
+			free(raw_data);
+			return NULL;
+		}
+		ret = WebPDecodeRGBAInto(raw_data, raw_data_size, image->data,
+		                         features.width * features.height * 4,
+		                         features.width * 4);
+	} else {
+		image = RCreateImage(features.width, features.height, False);
+		if (!image) {
+			RErrorCode = RERR_NOMEMORY;
+			free(raw_data);
+			return NULL;
+		}
+		ret = WebPDecodeRGBInto(raw_data, raw_data_size, image->data,
+		                        features.width * features.height * 3,
+		                        features.width * 3);
+	}
+
+	free(raw_data);
+
+	if (!ret) {
+		fprintf(stderr, "wrlib: Failed to decode WEBP from file \"%s\"\n", file_name);
+		RErrorCode = RERR_BADIMAGEFILE;
+		RReleaseImage(image);
+		return NULL;
+	}
+
+	return image;
+}