diff --git a/convert_image_to_webp.cpp b/convert_image_to_webp.cpp
index 104f117..df3f96d 100644
--- a/convert_image_to_webp.cpp
+++ b/convert_image_to_webp.cpp
@@ -9,12 +9,11 @@
 extern "C" {
 
     // 将输入的 JPG/PNG 数据转换为 WebP，并返回 WebP 数据
-    unsigned char *convert_image_to_webp(const uint8_t *input_data, size_t input_size, int target_width, int target_height, float quality_factor, size_t *output_size) {
+    unsigned char *convert_image_to_webp(const uint8_t *input_data, size_t input_size, int target_width, int target_height, float quality_factor, size_t *output_size, int preserve_alpha = 0) {
         int width, height, channels;
 
-
-        // 使用 stb_image 解码输入图像（强制加载为 RGB 而非 RGBA）
-        unsigned char *decoded_data = stbi_load_from_memory(input_data, input_size, &width, &height, &channels, 3); // 强制加载为 RGB
+        // 使用 stb_image 解码输入图像（根据 preserve_alpha 决定加载通道数）
+        unsigned char *decoded_data = stbi_load_from_memory(input_data, input_size, &width, &height, &channels, preserve_alpha ? 4 : 3); // 根据是否保留 alpha 通道加载
 
         if (!decoded_data) {
             return nullptr; // 图像解码失败
@@ -24,7 +23,7 @@ extern "C" {
         unsigned char *resized_data = decoded_data;
         if (target_width > 0 && target_height > 0) {
             // 分配用于存储调整大小后图像的缓冲区
-            resized_data = (unsigned char *)malloc(target_width * target_height * 3); // RGB 3 通道
+            resized_data = (unsigned char *)malloc(target_width * target_height * (preserve_alpha ? 4 : 3)); // 根据是否保留 alpha 通道调整缓冲区大小
 
             if (!resized_data) {
                 // 内存分配失败的处理
@@ -35,7 +34,7 @@ extern "C" {
 
             // 使用 stb_image_resize 调整图像大小
             int result = stbir_resize_uint8(decoded_data, width, height, 0,
-                                            resized_data, target_width, target_height, 0, 3);
+                                            resized_data, target_width, target_height, 0, preserve_alpha ? 4 : 3);
 
             if (!result) {
                 // 如果调整大小失败，释放已分配的内存
@@ -51,7 +50,11 @@ extern "C" {
 
         // 使用 libwebp 的有损编码函数（WebPEncodeRGB）将 RGB 图像编码为 WebP
         unsigned char *webp_output = NULL;
-        *output_size = WebPEncodeRGB(resized_data, target_width, target_height, target_width * 3, quality_factor, &webp_output);
+        if (preserve_alpha) {
+            *output_size = WebPEncodeRGBA(resized_data, target_width, target_height, target_width * 4, quality_factor, &webp_output);
+        } else {
+            *output_size = WebPEncodeRGB(resized_data, target_width, target_height, target_width * 3, quality_factor, &webp_output);
+        }
 
         // 释放解码后的图像内存
         stbi_image_free(decoded_data);