Tests added

This commit is contained in:
nfnt 2012-08-03 18:12:26 +02:00
parent c2ffff5712
commit fdc4a64918
3 changed files with 87 additions and 10 deletions

View File

@ -29,10 +29,49 @@ resize.Resize(w int, h int, img image.Image, interp InterpolationFunction) image
The provided interpolation functions are
- NearestNeighbor: Nearest-neighbor interpolation
- Bilinear: Bilinear interpolation
- Bicubic: Bicubic interpolation
- Lanczos3: Convolution with windowed Sinc function, a=3
- NearestNeighbor: [Nearest-neighbor interpolation](http://en.wikipedia.org/wiki/Nearest-neighbor_interpolation)
- Bilinear: [Bilinear interpolation](http://en.wikipedia.org/wiki/Bilinear_interpolation)
- Bicubic: [Bicubic interpolation](http://en.wikipedia.org/wiki/Bicubic_interpolation)
- Lanczos3: [Lanczos resampling](http://en.wikipedia.org/wiki/Lanczos_resampling) with a=3
Sample usage:
```go
package main
import (
"github.com/nfnt/resize"
"image/jpeg"
"os"
)
func main() {
// open "test.jpg"
file, err := os.Open("test.jpg")
if err != nil {
return
}
// decode jpeg into image.Image
img, err := jpeg.Decode(file)
if err != nil {
return
}
file.Close()
// resize to width 1000 using Lanczos resampling
m := resize.Resize(1000, -1, img, resize.Lanczos3)
out, err := os.Create("test_resized.jpg")
if err != nil {
return
}
defer out.Close()
// write new image to file
jpeg.Encode(out, m, nil)
}
```
License
=======

View File

@ -47,6 +47,13 @@ func (t *Trans2) Eval(x, y float32) (u, v float32) {
// Calculate scaling factors using old and new image dimensions.
func calcFactors(w, h int, wo, ho float32) (sx, sy float32) {
if w <= 0 {
w = -1
}
if h <= 0 {
h = -1
}
if w == -1 {
if h == -1 {
sx = 1.0

View File

@ -6,13 +6,44 @@ import (
"testing"
)
var img = image.NewGray16(image.Rect(0, 0, 3, 3))
func Test_Nearest(t *testing.T) {
img := image.NewGray16(image.Rect(0,0, 3,3))
img.Set(1,1, color.White)
img.Set(1, 1, color.White)
m := Resize(6,-1, img, NearestNeighbor)
m := Resize(6, -1, img, NearestNeighbor)
if m.At(2,2) != m.At(3,3) {
if m.At(2, 2) != m.At(3, 3) {
t.Fail()
}
}
func Test_Param1(t *testing.T) {
m := Resize(-1, -1, img, NearestNeighbor)
if m.Bounds() != img.Bounds() {
t.Fail()
}
}
func Test_Param2(t *testing.T) {
m := Resize(-100, -1, img, NearestNeighbor)
if m.Bounds() != img.Bounds() {
t.Fail()
}
}
func Test_Param3(t *testing.T) {
m := Resize(0, -1, img, NearestNeighbor)
if m.Bounds() != img.Bounds() {
t.Fail()
}
}
func Test_ZeroImg(t *testing.T) {
zeroImg := image.NewGray16(image.Rect(0, 0, 0, 0))
m := Resize(-1, -1, zeroImg, NearestNeighbor)
if m.Bounds() != zeroImg.Bounds() {
t.Fail()
}
}