feat(image_decoder): add webp decoder (#9175)

Signed-off-by: rongyichang <rongyichang@xiaomi.com>

examples/libs/libwebp/index.rst

@@ -0,0 +1,6 @@
+Open a WEBP image from file and variable
+----------------------------------------
+
+.. lv_example:: libs/libwebp/lv_example_libwebp_1
+  :language: c
+

examples/libs/libwebp/lv_example_libwebp.h

@@ -0,0 +1,38 @@
+/**
+ * @file lv_example_libwebp.h
+ *
+ */
+
+#ifndef LV_EXAMPLE_LIBWEBP_H
+#define LV_EXAMPLE_LIBWEBP_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*********************
+ *      INCLUDES
+ *********************/
+
+/*********************
+ *      DEFINES
+ *********************/
+
+/**********************
+ *      TYPEDEFS
+ **********************/
+
+/**********************
+ * GLOBAL PROTOTYPES
+ **********************/
+void lv_example_libwebp_1(void);
+
+/**********************
+ *      MACROS
+ **********************/
+
+#ifdef __cplusplus
+} /*extern "C"*/
+#endif
+
+#endif /*LV_EXAMPLE_LIBWEBP_H*/

examples/libs/libwebp/lv_example_libwebp_1.c

@@ -0,0 +1,31 @@
+#include "../../lv_examples.h"
+#if LV_BUILD_EXAMPLES
+
+#if LV_USE_LIBWEBP
+
+/**
+ * Load a WEBP image
+ */
+void lv_example_libwebp_1(void)
+{
+    lv_obj_t * img;
+
+    img = lv_image_create(lv_screen_active());
+    /* Assuming a File system is attached to letter 'A'
+     * E.g. set LV_USE_FS_STDIO 'A' in lv_conf.h */
+    lv_image_set_src(img, "A:lvgl/examples/libs/libwebp/rose.webp");
+    lv_obj_center(img);
+}
+
+#else
+
+void lv_example_libwebp_1(void)
+{
+    lv_obj_t * label = lv_label_create(lv_screen_active());
+    lv_label_set_text(label, "Libwebp is not installed");
+    lv_obj_center(label);
+}
+
+#endif
+
+#endif

examples/libs/lv_example_libs.h

@@ -26,6 +26,7 @@ extern "C" {
 #include "rlottie/lv_example_rlottie.h"
 #include "tjpgd/lv_example_tjpgd.h"
 #include "libjpeg_turbo/lv_example_libjpeg_turbo.h"
+#include "libwebp/lv_example_libwebp.h"
 #include "tiny_ttf/lv_example_tiny_ttf.h"
 #include "svg/lv_example_svg.h"