move gifresize into its own repo

third_party/gifresize/gifresize.go

@@ -1,64 +0,0 @@
-// Copyright 2013 Daniel Pupius. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Package gifresize resizes animated gifs.
-//
-// Frames in an animated gif aren't necessarily the same size, subsequent
-// frames are overlayed on previous frames. Therefore, resizing the frames
-// individually may cause problems due to aliasing of transparent pixels. This
-// package tries to avoid this by building frames from all previous frames and
-// resizing the frames as RGB.
-package gifresize
-
-import (
-	"image"
-	"image/color"
-	"image/draw"
-	"image/gif"
-	"io"
-)
-
-// TransformFunc is a function that transforms an image.
-type TransformFunc func(image.Image) image.Image
-
-// Process the GIF read from r, applying transform to each frame, and writing
-// the result to w.
-func Process(w io.Writer, r io.Reader, transform TransformFunc) error {
-	// Decode the original gif.
-	im, err := gif.DecodeAll(r)
-	if err != nil {
-		return err
-	}
-
-	// Create a new RGBA image to hold the incremental frames.
-	firstFrame := im.Image[0].Bounds()
-	b := image.Rect(0, 0, firstFrame.Dx(), firstFrame.Dy())
-	img := image.NewRGBA(b)
-
-	// Resize each frame.
-	for index, frame := range im.Image {
-		bounds := frame.Bounds()
-		draw.Draw(img, bounds, frame, bounds.Min, draw.Over)
-		im.Image[index] = imageToPaletted(transform(img), frame.Palette)
-	}
-
-	return gif.EncodeAll(w, im)
-}
-
-func imageToPaletted(img image.Image, p color.Palette) *image.Paletted {
-	b := img.Bounds()
-	pm := image.NewPaletted(b, p)
-	draw.FloydSteinberg.Draw(pm, b, img, image.ZP)
-	return pm
-}

transform.go

@@ -22,7 +22,7 @@ import (
 	"image/png"
 
 	"github.com/disintegration/imaging"
-	"willnorris.com/go/imageproxy/third_party/gifresize"
+	"willnorris.com/go/gifresize"
 )
 
 // default compression quality of resized jpegs