WRaster: Add optional support to JPEG XL

Detect if libjxl is intalled, and build-in support in raster lib.
Feature can be disabled/enabled at configure time.

configure.ac

@@ -766,6 +766,19 @@ m4_divert_pop([INIT_PREPARE])dnl
 WM_IMGFMT_CHECK_JPEG
 
 
+dnl JXL Support
+dnl ============
+m4_divert_push([INIT_PREPARE])dnl
+AC_ARG_ENABLE([jxl],
+    [AS_HELP_STRING([--disable-jxl], [disable JXL support through libjxl])],
+    [AS_CASE(["$enableval"],
+        [yes|no], [],
+        [AC_MSG_ERROR([bad value $enableval for --enable-jxl])] )],
+    [enable_jxl=auto])
+m4_divert_pop([INIT_PREPARE])dnl
+WM_IMGFMT_CHECK_JXL
+
+
 dnl GIF Support
 dnl ============
 m4_divert_push([INIT_PREPARE])dnl

doc/build/Compilation.texi

@@ -204,6 +204,11 @@ Note that if you don't have it, @command{configure} will issue a big warning in
 this is because JPEG images are often used in themes and for background images
 so you probably want this format supported.
 
+@item @emph{libjxl} 0.7.0 or newer
+
+For @emph{JXL} image support,
+@uref{https://github.com/libjxl/libjxl}
+
 @item @emph{libgif} 2.2 or @emph{libungif}
 
 For @emph{GIF} image support,
@@ -477,6 +482,9 @@ Disable GIF support in @emph{WRaster} library; when enabled use @file{libgif} or
 @item --disable-jpeg
 Disable JPEG support in @emph{WRaster} library; when enabled use @file{libjpeg}.
 
+@item --disable-jxl
+Disable JPEG-XL support in @emph{WRaster} library; when enabled use @file{libjxl}.
+
 @item --without-libbsd
 Refuse use of the @file{libbsd} compatibility library in @emph{WINGs} utility library,
 even if your system provides it.

m4/wm_imgfmt_check.m4

@@ -113,6 +113,37 @@ AC_DEFUN_ONCE([WM_IMGFMT_CHECK_JPEG],
 ]) dnl AC_DEFUN
 
 
+# WM_IMGFMT_CHECK_JXL
+# -------------------
+#
+# Check for JXL (JPEG XL) file support through 'libjxl'
+# The check depends on variable 'enable_jxl' 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_JXL],
+[WM_LIB_CHECK([JXL], [-ljxl], [JxlDecoderCreate], [$XLFLAGS $XLIBS],
+    [AC_COMPILE_IFELSE(
+                [AC_LANG_PROGRAM(
+                    [@%:@include <stdlib.h>
+@%:@include <jxl/decode.h>],
+                    [  JxlDecoder* dec = JxlDecoderCreate(NULL);
+  JxlDecoderDestroy(dec);])],
+                [],
+                [AS_ECHO([failed])
+                 AS_ECHO(["$as_me: error: found $CACHEVAR but cannot compile header"])
+                 AS_ECHO(["$as_me: error:   - does header 'jxl/decode.h' exists? (is package 'libjxl-dev' missing?)"])
+                 AS_ECHO(["$as_me: error:   - version of header is not supported? (report to dev team)"])
+                 AC_MSG_ERROR([JXL library is not usable, cannot continue])])
+           ],
+    [supported_gfx], [GFXLIBS])dnl
+]) dnl AC_DEFUN
+
+
 # WM_IMGFMT_CHECK_PNG
 # -------------------
 #

wrlib/Makefile.am

@@ -58,6 +58,10 @@ libwraster_la_SOURCES += load_jpeg.c
 libwraster_la_SOURCES += save_jpeg.c
 endif
 
+if USE_JXL
+libwraster_la_SOURCES += load_jxl.c
+endif
+
 if USE_PNG
 libwraster_la_SOURCES += load_png.c
 libwraster_la_SOURCES += save_png.c

wrlib/imgformat.h

@@ -38,12 +38,13 @@ typedef enum {
 	IM_PPM     =  4,
 	IM_JPEG    =  5,
 	IM_GIF     =  6,
-	IM_WEBP    =  7
+	IM_WEBP    =  7,
+	IM_JXL     =  8
 } WRImgFormat;
 
 /* How many image types we have. */
 /* Increase this when adding new image types! */
-#define IM_TYPES    7
+#define IM_TYPES    8
 
 /*
  * Function for Loading in a specific format
@@ -64,6 +65,10 @@ RImage *RLoadPNG(RContext *context, const char *file);
 RImage *RLoadJPEG(const char *file);
 #endif
 
+#ifdef USE_JXL
+RImage *RLoadJXL(const char *file);
+#endif
+
 #ifdef USE_GIF
 RImage *RLoadGIF(const char *file, int index);
 #endif

wrlib/load.c

@@ -3,7 +3,7 @@
  * Raster graphics library
  *
  * Copyright (c) 1997-2003 Alfredo K. Kojima
- * Copyright (c) 2014-2021 Window Maker Team
+ * Copyright (c) 2014-2025 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 +93,9 @@ char **RSupportedFileFormats(void)
 #ifdef USE_JPEG
 	tmp[i++] = "JPEG";
 #endif
+#ifdef USE_JXL
+	tmp[i++] = "JXL";
+#endif
 #ifdef USE_GIF
 	tmp[i++] = "GIF";
 #endif
@@ -219,6 +222,12 @@ RImage *RLoadImage(RContext *context, const char *file, int index)
 		break;
 #endif				/* USE_JPEG */
 
+#ifdef USE_JXL
+	case IM_JXL:
+		image = RLoadJXL(file);
+		break;
+#endif				/* USE_JXL */
+
 #ifdef USE_GIF
 	case IM_GIF:
 		image = RLoadGIF(file, index);
@@ -305,6 +314,11 @@ char *RGetImageFileFormat(const char *file)
 		return "JPEG";
 #endif				/* USE_JPEG */
 
+#ifdef USE_JXL
+	case IM_JXL:
+		return "JXL";
+#endif				/* USE_JXL */
+
 #ifdef USE_GIF
 	case IM_GIF:
 		return "GIF";
@@ -377,6 +391,13 @@ static WRImgFormat identFile(const char *path)
 	if (buffer[0] == 0xff && buffer[1] == 0xd8)
 		return IM_JPEG;
 
+	/* check for JXL */
+	if ((buffer[0] == 0xff && buffer[1] == 0x0a) ||  /* naked codestream */
+	    (buffer[0] == 0x00 && buffer[1] == 0x00 && buffer[2] == 0x00 && buffer[3] == 0x0c &&  /* container format */
+	     buffer[4] == 0x4a && buffer[5] == 0x58 && buffer[6] == 0x4c && buffer[7] == 0x20 &&
+	     buffer[8] == 0x0d && buffer[9] == 0x0a && buffer[10] == 0x87 && buffer[11] == 0x0a))
+		return IM_JXL;
+
 	/* check for GIF */
 	if (buffer[0] == 'G' && buffer[1] == 'I' && buffer[2] == 'F' && buffer[3] == '8' &&
 	    (buffer[4] == '7' ||  buffer[4] == '9') && buffer[5] == 'a')

wrlib/load_jxl.c

@@ -0,0 +1,211 @@
+/* load_jxl.c - load JXL (JPEG XL) image from file
+ *
+ * Raster graphics library
+ *
+ * Copyright (c) 2025 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>
+
+#ifdef USE_JXL
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include <jxl/decode.h>
+
+#include "wraster.h"
+#include "imgformat.h"
+#include "wr_i18n.h"
+
+static unsigned char *do_read_file(const char *filename, size_t *size)
+{
+	FILE *file;
+	struct stat st;
+	unsigned char *data;
+
+	if (stat(filename, &st) != 0) {
+		RErrorCode = RERR_OPEN;
+		return NULL;
+	}
+
+	file = fopen(filename, "rb");
+	if (!file) {
+		RErrorCode = RERR_OPEN;
+		return NULL;
+	}
+
+	*size = st.st_size;
+	data = malloc(*size);
+	if (!data) {
+		RErrorCode = RERR_NOMEMORY;
+		fclose(file);
+		return NULL;
+	}
+
+	if (fread(data, 1, *size, file) != *size) {
+		RErrorCode = RERR_READ;
+		free(data);
+		fclose(file);
+		return NULL;
+	}
+
+	fclose(file);
+	return data;
+}
+
+RImage *RLoadJXL(const char *file)
+{
+	RImage *image = NULL;
+	unsigned char *data = NULL, *pixels = NULL;
+	size_t size;
+	JxlDecoder *dec = NULL;
+	JxlDecoderStatus status;
+	JxlBasicInfo info;
+	JxlPixelFormat format;
+	size_t buffer_size;
+	int width = 0, height = 0;
+	int has_alpha = 0;
+
+	/* Load file data */
+	data = do_read_file(file, &size);
+	if (!data)
+		return NULL;
+
+	/* Create decoder */
+	dec = JxlDecoderCreate(NULL);
+	if (!dec) {
+		RErrorCode = RERR_NOMEMORY;
+		goto error;
+	}
+
+	/* Subscribe to basic info and full image */
+	if (JxlDecoderSubscribeEvents(dec, JXL_DEC_BASIC_INFO | JXL_DEC_FULL_IMAGE) != JXL_DEC_SUCCESS) {
+		RErrorCode = RERR_BADIMAGEFILE;
+		goto error;
+	}
+
+	/* Set input data */
+	if (JxlDecoderSetInput(dec, data, size) != JXL_DEC_SUCCESS) {
+		RErrorCode = RERR_BADIMAGEFILE;
+		goto error;
+	}
+
+	/* Process events */
+	for (;;) {
+		status = JxlDecoderProcessInput(dec);
+
+		if (status == JXL_DEC_ERROR) {
+			RErrorCode = RERR_BADIMAGEFILE;
+			goto error;
+		}
+
+		if (status == JXL_DEC_NEED_MORE_INPUT) {
+			RErrorCode = RERR_BADIMAGEFILE;
+			goto error;
+		}
+
+		if (status == JXL_DEC_BASIC_INFO) {
+			if (JxlDecoderGetBasicInfo(dec, &info) != JXL_DEC_SUCCESS) {
+				RErrorCode = RERR_BADIMAGEFILE;
+				goto error;
+			}
+
+			width = info.xsize;
+			height = info.ysize;
+
+			if (width < 1 || height < 1) {
+				RErrorCode = RERR_BADIMAGEFILE;
+				goto error;
+			}
+
+			/* Check if image has alpha channel */
+			has_alpha = (info.alpha_bits > 0);
+			
+			/* Set pixel format based on alpha channel presence */
+			if (has_alpha) {
+				format.num_channels = 4;  /* RGBA */
+			} else {
+				format.num_channels = 3;  /* RGB */
+			}
+			format.data_type = JXL_TYPE_UINT8;
+			format.endianness = JXL_NATIVE_ENDIAN;
+			format.align = 0;
+
+		} else if (status == JXL_DEC_NEED_IMAGE_OUT_BUFFER) {
+			/* Allocate image with or without alpha */
+			image = RCreateImage(width, height, has_alpha ? True : False);
+			if (!image) {
+				RErrorCode = RERR_NOMEMORY;
+				goto error;
+			}
+
+			/* Determine buffer size */
+			if (JxlDecoderImageOutBufferSize(dec, &format, &buffer_size) != JXL_DEC_SUCCESS) {
+				RErrorCode = RERR_BADIMAGEFILE;
+				goto error;
+			}
+
+			/* Allocate buffer */
+			pixels = malloc(buffer_size);
+			if (!pixels) {
+				RErrorCode = RERR_NOMEMORY;
+				goto error;
+			}
+
+			/* Set output buffer */
+			if (JxlDecoderSetImageOutBuffer(dec, &format, pixels, buffer_size) != JXL_DEC_SUCCESS) {
+				RErrorCode = RERR_BADIMAGEFILE;
+				goto error;
+			}
+		} else if (status == JXL_DEC_FULL_IMAGE) {
+			/* Image is ready, copy data directly for RGB or RGBA */
+			if (has_alpha) {
+				/* RGBA format - copy directly */
+				memcpy(image->data, pixels, width * height * 4);
+			} else {
+				/* RGB format - copy directly */
+				memcpy(image->data, pixels, width * height * 3);
+			}
+			break;
+		} else if (status == JXL_DEC_SUCCESS) {
+			/* All done */
+			break;
+		}
+	}
+
+	free(data);
+	free(pixels);
+	JxlDecoderDestroy(dec);
+	return image;
+
+error:
+	if (data)
+		free(data);
+	if (pixels)
+		free(pixels);
+	if (image)
+		RReleaseImage(image);
+	if (dec)
+		JxlDecoderDestroy(dec);
+	return NULL;
+}
+
+#endif /* USE_JXL */

wrlib/po/Makefile.am

@@ -29,6 +29,7 @@ POTFILES  = \
 	$(top_srcdir)/wrlib/load_ppm.c	\
 	$(top_srcdir)/wrlib/load_gif.c	\
 	$(top_srcdir)/wrlib/load_jpeg.c	\
+	$(top_srcdir)/wrlib/load_jxl.c	\
 	$(top_srcdir)/wrlib/load_png.c	\
 	$(top_srcdir)/wrlib/load_tiff.c	\
 	$(top_srcdir)/wrlib/load_xpm.c	\