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-rw-r--r--vendor/github.com/nfnt/resize/thumbnail.go55
1 files changed, 55 insertions, 0 deletions
diff --git a/vendor/github.com/nfnt/resize/thumbnail.go b/vendor/github.com/nfnt/resize/thumbnail.go
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+++ b/vendor/github.com/nfnt/resize/thumbnail.go
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+/*
+Copyright (c) 2012, Jan Schlicht <jan.schlicht@gmail.com>
+
+Permission to use, copy, modify, and/or distribute this software for any purpose
+with or without fee is hereby granted, provided that the above copyright notice
+and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
+THIS SOFTWARE.
+*/
+
+package resize
+
+import (
+ "image"
+)
+
+// Thumbnail will downscale provided image to max width and height preserving
+// original aspect ratio and using the interpolation function interp.
+// It will return original image, without processing it, if original sizes
+// are already smaller than provided constraints.
+func Thumbnail(maxWidth, maxHeight uint, img image.Image, interp InterpolationFunction) image.Image {
+ origBounds := img.Bounds()
+ origWidth := uint(origBounds.Dx())
+ origHeight := uint(origBounds.Dy())
+ newWidth, newHeight := origWidth, origHeight
+
+ // Return original image if it have same or smaller size as constraints
+ if maxWidth >= origWidth && maxHeight >= origHeight {
+ return img
+ }
+
+ // Preserve aspect ratio
+ if origWidth > maxWidth {
+ newHeight = uint(origHeight * maxWidth / origWidth)
+ if newHeight < 1 {
+ newHeight = 1
+ }
+ newWidth = maxWidth
+ }
+
+ if newHeight > maxHeight {
+ newWidth = uint(newWidth * maxHeight / newHeight)
+ if newWidth < 1 {
+ newWidth = 1
+ }
+ newHeight = maxHeight
+ }
+ return Resize(newWidth, newHeight, img, interp)
+}