Ticket #2454: image_filter_scale.patch

src/http/modules/ngx_http_image_filter_module.c

@@ -48 +48 @@
 
     ngx_flag_t                   transparency;
     ngx_flag_t                   interlace;
+    ngx_flag_t                   use_scale_function;
 
     ngx_http_complex_value_t    *wcv;
     ngx_http_complex_value_t    *hcv;
@@ -163 +164 @@
       offsetof(ngx_http_image_filter_conf_t, interlace),
       NULL },
 
+    { ngx_string("image_filter_use_scale_function"),
+      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
+      ngx_conf_set_flag_slot,
+      NGX_HTTP_LOC_CONF_OFFSET,
+      offsetof(ngx_http_image_filter_conf_t, use_scale_function),
+      NULL },
+
     { ngx_string("image_filter_buffer"),
       NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
       ngx_conf_set_size_slot,
@@ -851 +859 @@
 
     colors = gdImageColorsTotal(src);
 
-    if (colors && conf->transparency) {
+    if (colors && !conf->use_scale_function && conf->transparency) {
         transparent = gdImageGetTransparent(src);
 
         if (transparent != -1) {
@@ -872 +880 @@
 
 transparent:
 
-    gdImageColorTransparent(src, -1);
+    if (!conf->use_scale_function) {
+        gdImageColorTransparent(src, -1);
+    }
 
     dx = sx;
     dy = sy;
@@ -919 +929 @@
         }
     }
 
-    if (resize) {
+    if (resize && conf->use_scale_function) {
+        gdImageSetInterpolationMethod(src, GD_BICUBIC);
+        dst = gdImageScale(src, dx, dy);
+        if (dst == NULL) {
+            gdImageDestroy(src);
+            return NULL;
+        }
+        gdImageDestroy(src);
+    } else if (resize) {
         dst = ngx_http_image_new(r, dx, dy, palette);
         if (dst == NULL) {
             gdImageDestroy(src);
@@ -1023 +1041 @@
                            "image crop: %d x %d @ %d x %d",
                            dx, dy, ox, oy);
 
-            if (colors == 0) {
+            if (!conf->use_scale_function && colors == 0) {
                 gdImageSaveAlpha(dst, 1);
                 gdImageAlphaBlending(dst, 0);
             }
 
             gdImageCopy(dst, src, 0, 0, ox, oy, dx - ox, dy - oy);
 
-            if (colors) {
+            if (!conf->use_scale_function && colors) {
                 gdImageTrueColorToPalette(dst, 1, 256);
             }
 
@@ -1038 +1056 @@
         }
     }
 
-    if (transparent != -1 && colors) {
+    if (!conf->use_scale_function && transparent != -1 && colors) {
         gdImageColorTransparent(dst, gdImageColorExact(dst, red, green, blue));
     }
 
@@ -1301 +1319 @@
     conf->sharpen = NGX_CONF_UNSET_UINT;
     conf->transparency = NGX_CONF_UNSET;
     conf->interlace = NGX_CONF_UNSET;
+    conf->use_scale_function = NGX_CONF_UNSET;
     conf->buffer_size = NGX_CONF_UNSET_SIZE;
 
     return conf;
@@ -1361 +1380 @@
 
     ngx_conf_merge_value(conf->interlace, prev->interlace, 0);
 
+    ngx_conf_merge_value(conf->use_scale_function, prev->use_scale_function, 0);
+
     ngx_conf_merge_size_value(conf->buffer_size, prev->buffer_size,
                               1 * 1024 * 1024);