Make filters low-level

processing/apply_filters.go

@@ -2,7 +2,6 @@ package processing
 
 import (
 	"github.com/imgproxy/imgproxy/v3/imagedata"
-	"github.com/imgproxy/imgproxy/v3/imath"
 	"github.com/imgproxy/imgproxy/v3/options"
 	"github.com/imgproxy/imgproxy/v3/vips"
 )
@@ -20,35 +19,7 @@ func applyFilters(pctx *pipelineContext, img *vips.Image, po *options.Processing
 		return err
 	}
 
-	// When image has alpha, we need to premultiply it to get rid of black edges
-	if err := img.Premultiply(); err != nil {
-		return err
-	}
-
-	if po.Blur > 0 {
-		if err := img.Blur(po.Blur); err != nil {
-			return err
-		}
-	}
-
-	if po.Sharpen > 0 {
-		if err := img.Sharpen(po.Sharpen); err != nil {
-			return err
-		}
-	}
-
-	if po.Pixelate > 1 {
-		pixels := imath.Min(po.Pixelate, imath.Min(img.Width(), img.Height()))
-		if err := img.Pixelate(pixels); err != nil {
-			return err
-		}
-	}
-
-	if err := img.Unpremultiply(); err != nil {
-		return err
-	}
-
-	if err := img.CastUchar(); err != nil {
+	if err := img.ApplyFilters(po.Blur, po.Sharpen, po.Pixelate); err != nil {
 		return err
 	}
 

vips/vips.c

@@ -177,22 +177,6 @@ vips_addalpha_go(VipsImage *in, VipsImage **out) {
   return vips_addalpha(in, out, NULL);
 }
 
-int
-vips_premultiply_go(VipsImage *in, VipsImage **out) {
-  if (!vips_image_hasalpha(in))
-    return vips_copy(in, out, NULL);
-
-  return vips_premultiply(in, out, NULL);
-}
-
-int
-vips_unpremultiply_go(VipsImage *in, VipsImage **out) {
-  if (!vips_image_hasalpha(in))
-    return vips_copy(in, out, NULL);
-
-  return vips_unpremultiply(in, out, NULL);
-}
-
 int
 vips_copy_go(VipsImage *in, VipsImage **out) {
   return vips_copy(in, out, NULL);
@@ -229,55 +213,6 @@ vips_resize_go(VipsImage *in, VipsImage **out, double wscale, double hscale) {
   return 0;
 }
 
-int
-vips_pixelate(VipsImage *in, VipsImage **out, int pixels) {
-  VipsImage *base = vips_image_new();
-  VipsImage **t = (VipsImage **) vips_object_local_array(VIPS_OBJECT(base), 3);
-
-  int w, h, tw, th;
-
-  w = in->Xsize;
-  h = in->Ysize;
-
-  tw = (int)((double)(w + pixels - 1) / pixels) * pixels;
-  th = (int)((double)(h + pixels - 1) / pixels) * pixels;
-
-  if (tw > w || th > h) {
-    if (vips_embed(in, &t[0], 0, 0, tw, th, "extend", VIPS_EXTEND_COPY, NULL)) {
-      clear_image(&base);
-      return 1;
-    }
-  } else {
-    if (vips_copy(in, &t[0], NULL)) {
-      clear_image(&base);
-      return 1;
-    }
-  }
-
-  if (
-    vips_shrink(t[0], &t[1], pixels, pixels, NULL) ||
-    vips_zoom(t[1], &t[2], pixels, pixels, NULL)
-  ) {
-      clear_image(&base);
-      return 1;
-  }
-
-  if (tw > w || th > h) {
-    if (vips_extract_area(t[2], out, 0, 0, w, h, NULL)) {
-        clear_image(&base);
-        return 1;
-    }
-  } else {
-    if (vips_copy(t[2], out, NULL)) {
-        clear_image(&base);
-        return 1;
-    }
-  }
-
-  clear_image(&base);
-  return 0;
-}
-
 int
 vips_icc_is_srgb_iec61966(VipsImage *in) {
   const void *data;
@@ -364,13 +299,100 @@ vips_smartcrop_go(VipsImage *in, VipsImage **out, int width, int height) {
 }
 
 int
-vips_gaussblur_go(VipsImage *in, VipsImage **out, double sigma) {
-  return vips_gaussblur(in, out, sigma, NULL);
-}
+vips_apply_filters(VipsImage *in, VipsImage **out, double blur_sigma,
+  double sharp_sigma, int pixelate_pixels) {
 
-int
-vips_sharpen_go(VipsImage *in, VipsImage **out, double sigma) {
-  return vips_sharpen(in, out, "sigma", sigma, NULL);
+  VipsImage *base = vips_image_new();
+  VipsImage **t = (VipsImage **) vips_object_local_array(VIPS_OBJECT(base), 9);
+
+  VipsInterpretation interpretation = in->Type;
+  VipsBandFormat format = in->BandFmt;
+  gboolean premultiplied = FALSE;
+
+  if ((blur_sigma > 0 || sharp_sigma > 0) && vips_image_hasalpha(in)) {
+    if (vips_premultiply(in, &t[0], NULL)) {
+      clear_image(&base);
+      return 1;
+    }
+
+    in = t[0];
+    premultiplied = TRUE;
+  }
+
+  if (blur_sigma > 0.0) {
+    if (vips_gaussblur(in, &t[1], blur_sigma, NULL)) {
+      clear_image(&base);
+      return 1;
+    }
+
+    in = t[1];
+  }
+
+  if (sharp_sigma > 0.0) {
+    if (vips_sharpen(in, &t[2], "sigma", sharp_sigma, NULL)) {
+      clear_image(&base);
+      return 1;
+    }
+
+    in = t[2];
+  }
+
+  pixelate_pixels = VIPS_MIN(pixelate_pixels, VIPS_MAX(in->Xsize, in->Ysize));
+
+  if (pixelate_pixels > 1) {
+    int w, h, tw, th;
+
+    w = in->Xsize;
+    h = in->Ysize;
+
+    tw = (int)(VIPS_CEIL((double)w / pixelate_pixels)) * pixelate_pixels;
+    th = (int)(VIPS_CEIL((double)h / pixelate_pixels)) * pixelate_pixels;
+
+    if (tw > w || th > h) {
+      if (vips_embed(in, &t[3], 0, 0, tw, th, "extend", VIPS_EXTEND_MIRROR, NULL)) {
+        clear_image(&base);
+        return 1;
+      }
+
+      in = t[3];
+    }
+
+    if (
+      vips_shrink(in, &t[4], pixelate_pixels, pixelate_pixels, NULL) ||
+      vips_zoom(t[4], &t[5], pixelate_pixels, pixelate_pixels, NULL)
+    ) {
+        clear_image(&base);
+        return 1;
+    }
+
+    in = t[5];
+
+    if (tw > w || th > h) {
+      if (vips_extract_area(in, &t[6], 0, 0, w, h, NULL)) {
+          clear_image(&base);
+          return 1;
+      }
+
+      in = t[6];
+    }
+  }
+
+  if (premultiplied) {
+    if (vips_unpremultiply(in, &t[7], NULL)) {
+      clear_image(&base);
+      return 1;
+    }
+
+    in = t[7];
+  }
+
+  int res =
+    vips_colourspace(in, &t[8], interpretation, NULL) ||
+    vips_cast(t[8], out, format, NULL);
+
+  clear_image(&base);
+
+  return res;
 }
 
 int

vips/vips.go

@@ -363,28 +363,6 @@ func (img *Image) HasAlpha() bool {
 	return C.vips_image_hasalpha(img.VipsImage) > 0
 }
 
-func (img *Image) Premultiply() error {
-	var tmp *C.VipsImage
-
-	if C.vips_premultiply_go(img.VipsImage, &tmp) != 0 {
-		return Error()
-	}
-
-	C.swap_and_clear(&img.VipsImage, tmp)
-	return nil
-}
-
-func (img *Image) Unpremultiply() error {
-	var tmp *C.VipsImage
-
-	if C.vips_unpremultiply_go(img.VipsImage, &tmp) != 0 {
-		return Error()
-	}
-
-	C.swap_and_clear(&img.VipsImage, tmp)
-	return nil
-}
-
 func (img *Image) GetInt(name string) (int, error) {
 	var i C.int
 
@@ -499,18 +477,6 @@ func (img *Image) Resize(wscale, hscale float64) error {
 	return nil
 }
 
-func (img *Image) Pixelate(pixels int) error {
-	var tmp *C.VipsImage
-
-	if C.vips_pixelate(img.VipsImage, &tmp, C.int(pixels)) != 0 {
-		return Error()
-	}
-
-	C.swap_and_clear(&img.VipsImage, tmp)
-
-	return nil
-}
-
 func (img *Image) Orientation() C.int {
 	return C.vips_get_orientation(img.VipsImage)
 }
@@ -609,25 +575,15 @@ func (img *Image) Flatten(bg Color) error {
 	return nil
 }
 
-func (img *Image) Blur(sigma float32) error {
+func (img *Image) ApplyFilters(blurSigma, sharpSigma float32, pixelatePixels int) error {
 	var tmp *C.VipsImage
 
-	if C.vips_gaussblur_go(img.VipsImage, &tmp, C.double(sigma)) != 0 {
+	if C.vips_apply_filters(img.VipsImage, &tmp, C.double(blurSigma), C.double(sharpSigma), C.int(pixelatePixels)) != 0 {
 		return Error()
 	}
 
 	C.swap_and_clear(&img.VipsImage, tmp)
-	return nil
-}
-
-func (img *Image) Sharpen(sigma float32) error {
-	var tmp *C.VipsImage
 
-	if C.vips_sharpen_go(img.VipsImage, &tmp, C.double(sigma)) != 0 {
-		return Error()
-	}
-
-	C.swap_and_clear(&img.VipsImage, tmp)
 	return nil
 }
 

vips/vips.h

@@ -34,8 +34,6 @@ int vips_image_get_array_int_go(VipsImage *image, const char *name, int **out, i
 void vips_image_set_array_int_go(VipsImage *image, const char *name, const int *array, int n);
 
 int vips_addalpha_go(VipsImage *in, VipsImage **out);
-int vips_premultiply_go(VipsImage *in, VipsImage **out);
-int vips_unpremultiply_go(VipsImage *in, VipsImage **out);
 
 int vips_copy_go(VipsImage *in, VipsImage **out);
 
@@ -44,8 +42,6 @@ int vips_rad2float_go(VipsImage *in, VipsImage **out);
 
 int vips_resize_go(VipsImage *in, VipsImage **out, double wscale, double hscale);
 
-int vips_pixelate(VipsImage *in, VipsImage **out, int pixels);
-
 int vips_icc_is_srgb_iec61966(VipsImage *in);
 int vips_has_embedded_icc(VipsImage *in);
 int vips_icc_import_go(VipsImage *in, VipsImage **out);
@@ -64,8 +60,7 @@ int vips_trim(VipsImage *in, VipsImage **out, double threshold,
               gboolean smart, double r, double g, double b,
               gboolean equal_hor, gboolean equal_ver);
 
-int vips_gaussblur_go(VipsImage *in, VipsImage **out, double sigma);
-int vips_sharpen_go(VipsImage *in, VipsImage **out, double sigma);
+int vips_apply_filters(VipsImage *in, VipsImage **out, double blur_sigma, double sharp_sigma, int pixelate_pixels);
 
 int vips_flatten_go(VipsImage *in, VipsImage **out, double r, double g, double b);