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-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/.travis.yml7
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/LICENSE13
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/converter.go452
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/converter_test.go43
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/filters.go143
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/nearest.go318
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/nearest_test.go57
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/resize.go614
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/resize_test.go224
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/thumbnail.go55
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/thumbnail_test.go47
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/ycc.go227
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/ycc_test.go214
13 files changed, 2414 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/.travis.yml b/Godeps/_workspace/src/github.com/nfnt/resize/.travis.yml
new file mode 100644
index 000000000..57bd4a76e
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/.travis.yml
@@ -0,0 +1,7 @@
+language: go
+
+go:
+ - 1.1
+ - 1.2
+ - 1.3
+ - tip
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/LICENSE b/Godeps/_workspace/src/github.com/nfnt/resize/LICENSE
new file mode 100644
index 000000000..7836cad5f
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/LICENSE
@@ -0,0 +1,13 @@
+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.
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/converter.go b/Godeps/_workspace/src/github.com/nfnt/resize/converter.go
new file mode 100644
index 000000000..84bd284ba
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/converter.go
@@ -0,0 +1,452 @@
+/*
+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"
+
+// Keep value in [0,255] range.
+func clampUint8(in int32) uint8 {
+ // casting a negative int to an uint will result in an overflown
+ // large uint. this behavior will be exploited here and in other functions
+ // to achieve a higher performance.
+ if uint32(in) < 256 {
+ return uint8(in)
+ }
+ if in > 255 {
+ return 255
+ }
+ return 0
+}
+
+// Keep value in [0,65535] range.
+func clampUint16(in int64) uint16 {
+ if uint64(in) < 65536 {
+ return uint16(in)
+ }
+ if in > 65535 {
+ return 65535
+ }
+ return 0
+}
+
+func resizeGeneric(in image.Image, out *image.NRGBA64, scale float64, coeffs []int32, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var rgba [4]int64
+ var sum int64
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ coeff := coeffs[ci+i]
+ if coeff != 0 {
+ xi := start + i
+ switch {
+ case xi < 0:
+ xi = 0
+ case xi >= maxX:
+ xi = maxX
+ }
+ r, g, b, a := in.At(xi+in.Bounds().Min.X, x+in.Bounds().Min.Y).RGBA()
+
+ // reverse alpha-premultiplication.
+ if a != 0 {
+ r *= 0xffff
+ r /= a
+ g *= 0xffff
+ g /= a
+ b *= 0xffff
+ b /= a
+ }
+
+ rgba[0] += int64(coeff) * int64(r)
+ rgba[1] += int64(coeff) * int64(g)
+ rgba[2] += int64(coeff) * int64(b)
+ rgba[3] += int64(coeff) * int64(a)
+ sum += int64(coeff)
+ }
+ }
+
+ offset := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*8
+ value := clampUint16(rgba[0] / sum)
+ out.Pix[offset+0] = uint8(value >> 8)
+ out.Pix[offset+1] = uint8(value)
+ value = clampUint16(rgba[1] / sum)
+ out.Pix[offset+2] = uint8(value >> 8)
+ out.Pix[offset+3] = uint8(value)
+ value = clampUint16(rgba[2] / sum)
+ out.Pix[offset+4] = uint8(value >> 8)
+ out.Pix[offset+5] = uint8(value)
+ value = clampUint16(rgba[3] / sum)
+ out.Pix[offset+6] = uint8(value >> 8)
+ out.Pix[offset+7] = uint8(value)
+ }
+ }
+}
+
+func resizeRGBA(in *image.RGBA, out *image.NRGBA, scale float64, coeffs []int16, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var rgba [4]int32
+ var sum int32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ coeff := coeffs[ci+i]
+ if coeff != 0 {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 4
+ case xi >= maxX:
+ xi = 4 * maxX
+ default:
+ xi = 0
+ }
+
+ r := uint32(row[xi+0])
+ g := uint32(row[xi+1])
+ b := uint32(row[xi+2])
+ a := uint32(row[xi+3])
+
+ // reverse alpha-premultiplication.
+ if a != 0 {
+ r *= 0xffff
+ r /= a
+ g *= 0xffff
+ g /= a
+ b *= 0xffff
+ b /= a
+ }
+
+ rgba[0] += int32(coeff) * int32(r)
+ rgba[1] += int32(coeff) * int32(g)
+ rgba[2] += int32(coeff) * int32(b)
+ rgba[3] += int32(coeff) * int32(a)
+ sum += int32(coeff)
+ }
+ }
+
+ xo := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*4
+ out.Pix[xo+0] = clampUint8(rgba[0] / sum)
+ out.Pix[xo+1] = clampUint8(rgba[1] / sum)
+ out.Pix[xo+2] = clampUint8(rgba[2] / sum)
+ out.Pix[xo+3] = clampUint8(rgba[3] / sum)
+ }
+ }
+}
+
+func resizeNRGBA(in *image.NRGBA, out *image.NRGBA, scale float64, coeffs []int16, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var rgba [4]int32
+ var sum int32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ coeff := coeffs[ci+i]
+ if coeff != 0 {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 4
+ case xi >= maxX:
+ xi = 4 * maxX
+ default:
+ xi = 0
+ }
+ rgba[0] += int32(coeff) * int32(row[xi+0])
+ rgba[1] += int32(coeff) * int32(row[xi+1])
+ rgba[2] += int32(coeff) * int32(row[xi+2])
+ rgba[3] += int32(coeff) * int32(row[xi+3])
+ sum += int32(coeff)
+ }
+ }
+
+ xo := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*4
+ out.Pix[xo+0] = clampUint8(rgba[0] / sum)
+ out.Pix[xo+1] = clampUint8(rgba[1] / sum)
+ out.Pix[xo+2] = clampUint8(rgba[2] / sum)
+ out.Pix[xo+3] = clampUint8(rgba[3] / sum)
+ }
+ }
+}
+
+func resizeRGBA64(in *image.RGBA64, out *image.NRGBA64, scale float64, coeffs []int32, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var rgba [4]int64
+ var sum int64
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ coeff := coeffs[ci+i]
+ if coeff != 0 {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 8
+ case xi >= maxX:
+ xi = 8 * maxX
+ default:
+ xi = 0
+ }
+
+ r := uint32(uint16(row[xi+0])<<8 | uint16(row[xi+1]))
+ g := uint32(uint16(row[xi+2])<<8 | uint16(row[xi+3]))
+ b := uint32(uint16(row[xi+4])<<8 | uint16(row[xi+5]))
+ a := uint32(uint16(row[xi+6])<<8 | uint16(row[xi+7]))
+
+ // reverse alpha-premultiplication.
+ if a != 0 {
+ r *= 0xffff
+ r /= a
+ g *= 0xffff
+ g /= a
+ b *= 0xffff
+ b /= a
+ }
+
+ rgba[0] += int64(coeff) * int64(r)
+ rgba[1] += int64(coeff) * int64(g)
+ rgba[2] += int64(coeff) * int64(b)
+ rgba[3] += int64(coeff) * int64(a)
+ sum += int64(coeff)
+ }
+ }
+
+ xo := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*8
+ value := clampUint16(rgba[0] / sum)
+ out.Pix[xo+0] = uint8(value >> 8)
+ out.Pix[xo+1] = uint8(value)
+ value = clampUint16(rgba[1] / sum)
+ out.Pix[xo+2] = uint8(value >> 8)
+ out.Pix[xo+3] = uint8(value)
+ value = clampUint16(rgba[2] / sum)
+ out.Pix[xo+4] = uint8(value >> 8)
+ out.Pix[xo+5] = uint8(value)
+ value = clampUint16(rgba[3] / sum)
+ out.Pix[xo+6] = uint8(value >> 8)
+ out.Pix[xo+7] = uint8(value)
+ }
+ }
+}
+
+func resizeNRGBA64(in *image.NRGBA64, out *image.NRGBA64, scale float64, coeffs []int32, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var rgba [4]int64
+ var sum int64
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ coeff := coeffs[ci+i]
+ if coeff != 0 {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 8
+ case xi >= maxX:
+ xi = 8 * maxX
+ default:
+ xi = 0
+ }
+ rgba[0] += int64(coeff) * int64(uint16(row[xi+0])<<8|uint16(row[xi+1]))
+ rgba[1] += int64(coeff) * int64(uint16(row[xi+2])<<8|uint16(row[xi+3]))
+ rgba[2] += int64(coeff) * int64(uint16(row[xi+4])<<8|uint16(row[xi+5]))
+ rgba[3] += int64(coeff) * int64(uint16(row[xi+6])<<8|uint16(row[xi+7]))
+ sum += int64(coeff)
+ }
+ }
+
+ xo := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*8
+ value := clampUint16(rgba[0] / sum)
+ out.Pix[xo+0] = uint8(value >> 8)
+ out.Pix[xo+1] = uint8(value)
+ value = clampUint16(rgba[1] / sum)
+ out.Pix[xo+2] = uint8(value >> 8)
+ out.Pix[xo+3] = uint8(value)
+ value = clampUint16(rgba[2] / sum)
+ out.Pix[xo+4] = uint8(value >> 8)
+ out.Pix[xo+5] = uint8(value)
+ value = clampUint16(rgba[3] / sum)
+ out.Pix[xo+6] = uint8(value >> 8)
+ out.Pix[xo+7] = uint8(value)
+ }
+ }
+}
+
+func resizeGray(in *image.Gray, out *image.Gray, scale float64, coeffs []int16, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[(x-newBounds.Min.X)*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var gray int32
+ var sum int32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ coeff := coeffs[ci+i]
+ if coeff != 0 {
+ xi := start + i
+ switch {
+ case xi < 0:
+ xi = 0
+ case xi >= maxX:
+ xi = maxX
+ }
+ gray += int32(coeff) * int32(row[xi])
+ sum += int32(coeff)
+ }
+ }
+
+ offset := (y-newBounds.Min.Y)*out.Stride + (x - newBounds.Min.X)
+ out.Pix[offset] = clampUint8(gray / sum)
+ }
+ }
+}
+
+func resizeGray16(in *image.Gray16, out *image.Gray16, scale float64, coeffs []int32, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var gray int64
+ var sum int64
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ coeff := coeffs[ci+i]
+ if coeff != 0 {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 2
+ case xi >= maxX:
+ xi = 2 * maxX
+ default:
+ xi = 0
+ }
+ gray += int64(coeff) * int64(uint16(row[xi+0])<<8|uint16(row[xi+1]))
+ sum += int64(coeff)
+ }
+ }
+
+ offset := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*2
+ value := clampUint16(gray / sum)
+ out.Pix[offset+0] = uint8(value >> 8)
+ out.Pix[offset+1] = uint8(value)
+ }
+ }
+}
+
+func resizeYCbCr(in *ycc, out *ycc, scale float64, coeffs []int16, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var p [3]int32
+ var sum int32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ coeff := coeffs[ci+i]
+ if coeff != 0 {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 3
+ case xi >= maxX:
+ xi = 3 * maxX
+ default:
+ xi = 0
+ }
+ p[0] += int32(coeff) * int32(row[xi+0])
+ p[1] += int32(coeff) * int32(row[xi+1])
+ p[2] += int32(coeff) * int32(row[xi+2])
+ sum += int32(coeff)
+ }
+ }
+
+ xo := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*3
+ out.Pix[xo+0] = clampUint8(p[0] / sum)
+ out.Pix[xo+1] = clampUint8(p[1] / sum)
+ out.Pix[xo+2] = clampUint8(p[2] / sum)
+ }
+ }
+}
+
+func nearestYCbCr(in *ycc, out *ycc, scale float64, coeffs []bool, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var p [3]float32
+ var sum float32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ if coeffs[ci+i] {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 3
+ case xi >= maxX:
+ xi = 3 * maxX
+ default:
+ xi = 0
+ }
+ p[0] += float32(row[xi+0])
+ p[1] += float32(row[xi+1])
+ p[2] += float32(row[xi+2])
+ sum++
+ }
+ }
+
+ xo := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*3
+ out.Pix[xo+0] = floatToUint8(p[0] / sum)
+ out.Pix[xo+1] = floatToUint8(p[1] / sum)
+ out.Pix[xo+2] = floatToUint8(p[2] / sum)
+ }
+ }
+}
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/converter_test.go b/Godeps/_workspace/src/github.com/nfnt/resize/converter_test.go
new file mode 100644
index 000000000..85639efc2
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/converter_test.go
@@ -0,0 +1,43 @@
+package resize
+
+import (
+ "testing"
+)
+
+func Test_ClampUint8(t *testing.T) {
+ var testData = []struct {
+ in int32
+ expected uint8
+ }{
+ {0, 0},
+ {255, 255},
+ {128, 128},
+ {-2, 0},
+ {256, 255},
+ }
+ for _, test := range testData {
+ actual := clampUint8(test.in)
+ if actual != test.expected {
+ t.Fail()
+ }
+ }
+}
+
+func Test_ClampUint16(t *testing.T) {
+ var testData = []struct {
+ in int64
+ expected uint16
+ }{
+ {0, 0},
+ {65535, 65535},
+ {128, 128},
+ {-2, 0},
+ {65536, 65535},
+ }
+ for _, test := range testData {
+ actual := clampUint16(test.in)
+ if actual != test.expected {
+ t.Fail()
+ }
+ }
+}
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/filters.go b/Godeps/_workspace/src/github.com/nfnt/resize/filters.go
new file mode 100644
index 000000000..4ce04e389
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/filters.go
@@ -0,0 +1,143 @@
+/*
+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 (
+ "math"
+)
+
+func nearest(in float64) float64 {
+ if in >= -0.5 && in < 0.5 {
+ return 1
+ }
+ return 0
+}
+
+func linear(in float64) float64 {
+ in = math.Abs(in)
+ if in <= 1 {
+ return 1 - in
+ }
+ return 0
+}
+
+func cubic(in float64) float64 {
+ in = math.Abs(in)
+ if in <= 1 {
+ return in*in*(1.5*in-2.5) + 1.0
+ }
+ if in <= 2 {
+ return in*(in*(2.5-0.5*in)-4.0) + 2.0
+ }
+ return 0
+}
+
+func mitchellnetravali(in float64) float64 {
+ in = math.Abs(in)
+ if in <= 1 {
+ return (7.0*in*in*in - 12.0*in*in + 5.33333333333) * 0.16666666666
+ }
+ if in <= 2 {
+ return (-2.33333333333*in*in*in + 12.0*in*in - 20.0*in + 10.6666666667) * 0.16666666666
+ }
+ return 0
+}
+
+func sinc(x float64) float64 {
+ x = math.Abs(x) * math.Pi
+ if x >= 1.220703e-4 {
+ return math.Sin(x) / x
+ }
+ return 1
+}
+
+func lanczos2(in float64) float64 {
+ if in > -2 && in < 2 {
+ return sinc(in) * sinc(in*0.5)
+ }
+ return 0
+}
+
+func lanczos3(in float64) float64 {
+ if in > -3 && in < 3 {
+ return sinc(in) * sinc(in*0.3333333333333333)
+ }
+ return 0
+}
+
+// range [-256,256]
+func createWeights8(dy, filterLength int, blur, scale float64, kernel func(float64) float64) ([]int16, []int, int) {
+ filterLength = filterLength * int(math.Max(math.Ceil(blur*scale), 1))
+ filterFactor := math.Min(1./(blur*scale), 1)
+
+ coeffs := make([]int16, dy*filterLength)
+ start := make([]int, dy)
+ for y := 0; y < dy; y++ {
+ interpX := scale*(float64(y)+0.5) - 0.5
+ start[y] = int(interpX) - filterLength/2 + 1
+ interpX -= float64(start[y])
+ for i := 0; i < filterLength; i++ {
+ in := (interpX - float64(i)) * filterFactor
+ coeffs[y*filterLength+i] = int16(kernel(in) * 256)
+ }
+ }
+
+ return coeffs, start, filterLength
+}
+
+// range [-65536,65536]
+func createWeights16(dy, filterLength int, blur, scale float64, kernel func(float64) float64) ([]int32, []int, int) {
+ filterLength = filterLength * int(math.Max(math.Ceil(blur*scale), 1))
+ filterFactor := math.Min(1./(blur*scale), 1)
+
+ coeffs := make([]int32, dy*filterLength)
+ start := make([]int, dy)
+ for y := 0; y < dy; y++ {
+ interpX := scale*(float64(y)+0.5) - 0.5
+ start[y] = int(interpX) - filterLength/2 + 1
+ interpX -= float64(start[y])
+ for i := 0; i < filterLength; i++ {
+ in := (interpX - float64(i)) * filterFactor
+ coeffs[y*filterLength+i] = int32(kernel(in) * 65536)
+ }
+ }
+
+ return coeffs, start, filterLength
+}
+
+func createWeightsNearest(dy, filterLength int, blur, scale float64) ([]bool, []int, int) {
+ filterLength = filterLength * int(math.Max(math.Ceil(blur*scale), 1))
+ filterFactor := math.Min(1./(blur*scale), 1)
+
+ coeffs := make([]bool, dy*filterLength)
+ start := make([]int, dy)
+ for y := 0; y < dy; y++ {
+ interpX := scale*(float64(y)+0.5) - 0.5
+ start[y] = int(interpX) - filterLength/2 + 1
+ interpX -= float64(start[y])
+ for i := 0; i < filterLength; i++ {
+ in := (interpX - float64(i)) * filterFactor
+ if in >= -0.5 && in < 0.5 {
+ coeffs[y*filterLength+i] = true
+ } else {
+ coeffs[y*filterLength+i] = false
+ }
+ }
+ }
+
+ return coeffs, start, filterLength
+}
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/nearest.go b/Godeps/_workspace/src/github.com/nfnt/resize/nearest.go
new file mode 100644
index 000000000..888039d85
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/nearest.go
@@ -0,0 +1,318 @@
+/*
+Copyright (c) 2014, Charlie Vieth <charlie.vieth@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"
+
+func floatToUint8(x float32) uint8 {
+ // Nearest-neighbor values are always
+ // positive no need to check lower-bound.
+ if x > 0xfe {
+ return 0xff
+ }
+ return uint8(x)
+}
+
+func floatToUint16(x float32) uint16 {
+ if x > 0xfffe {
+ return 0xffff
+ }
+ return uint16(x)
+}
+
+func nearestGeneric(in image.Image, out *image.RGBA64, scale float64, coeffs []bool, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var rgba [4]float32
+ var sum float32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ if coeffs[ci+i] {
+ xi := start + i
+ switch {
+ case xi < 0:
+ xi = 0
+ case xi >= maxX:
+ xi = maxX
+ }
+ r, g, b, a := in.At(xi+in.Bounds().Min.X, x+in.Bounds().Min.Y).RGBA()
+ rgba[0] += float32(r)
+ rgba[1] += float32(g)
+ rgba[2] += float32(b)
+ rgba[3] += float32(a)
+ sum++
+ }
+ }
+
+ offset := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*8
+ value := floatToUint16(rgba[0] / sum)
+ out.Pix[offset+0] = uint8(value >> 8)
+ out.Pix[offset+1] = uint8(value)
+ value = floatToUint16(rgba[1] / sum)
+ out.Pix[offset+2] = uint8(value >> 8)
+ out.Pix[offset+3] = uint8(value)
+ value = floatToUint16(rgba[2] / sum)
+ out.Pix[offset+4] = uint8(value >> 8)
+ out.Pix[offset+5] = uint8(value)
+ value = floatToUint16(rgba[3] / sum)
+ out.Pix[offset+6] = uint8(value >> 8)
+ out.Pix[offset+7] = uint8(value)
+ }
+ }
+}
+
+func nearestRGBA(in *image.RGBA, out *image.RGBA, scale float64, coeffs []bool, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var rgba [4]float32
+ var sum float32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ if coeffs[ci+i] {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 4
+ case xi >= maxX:
+ xi = 4 * maxX
+ default:
+ xi = 0
+ }
+ rgba[0] += float32(row[xi+0])
+ rgba[1] += float32(row[xi+1])
+ rgba[2] += float32(row[xi+2])
+ rgba[3] += float32(row[xi+3])
+ sum++
+ }
+ }
+
+ xo := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*4
+ out.Pix[xo+0] = floatToUint8(rgba[0] / sum)
+ out.Pix[xo+1] = floatToUint8(rgba[1] / sum)
+ out.Pix[xo+2] = floatToUint8(rgba[2] / sum)
+ out.Pix[xo+3] = floatToUint8(rgba[3] / sum)
+ }
+ }
+}
+
+func nearestNRGBA(in *image.NRGBA, out *image.NRGBA, scale float64, coeffs []bool, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var rgba [4]float32
+ var sum float32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ if coeffs[ci+i] {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 4
+ case xi >= maxX:
+ xi = 4 * maxX
+ default:
+ xi = 0
+ }
+ rgba[0] += float32(row[xi+0])
+ rgba[1] += float32(row[xi+1])
+ rgba[2] += float32(row[xi+2])
+ rgba[3] += float32(row[xi+3])
+ sum++
+ }
+ }
+
+ xo := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*4
+ out.Pix[xo+0] = floatToUint8(rgba[0] / sum)
+ out.Pix[xo+1] = floatToUint8(rgba[1] / sum)
+ out.Pix[xo+2] = floatToUint8(rgba[2] / sum)
+ out.Pix[xo+3] = floatToUint8(rgba[3] / sum)
+ }
+ }
+}
+
+func nearestRGBA64(in *image.RGBA64, out *image.RGBA64, scale float64, coeffs []bool, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var rgba [4]float32
+ var sum float32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ if coeffs[ci+i] {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 8
+ case xi >= maxX:
+ xi = 8 * maxX
+ default:
+ xi = 0
+ }
+ rgba[0] += float32(uint16(row[xi+0])<<8 | uint16(row[xi+1]))
+ rgba[1] += float32(uint16(row[xi+2])<<8 | uint16(row[xi+3]))
+ rgba[2] += float32(uint16(row[xi+4])<<8 | uint16(row[xi+5]))
+ rgba[3] += float32(uint16(row[xi+6])<<8 | uint16(row[xi+7]))
+ sum++
+ }
+ }
+
+ xo := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*8
+ value := floatToUint16(rgba[0] / sum)
+ out.Pix[xo+0] = uint8(value >> 8)
+ out.Pix[xo+1] = uint8(value)
+ value = floatToUint16(rgba[1] / sum)
+ out.Pix[xo+2] = uint8(value >> 8)
+ out.Pix[xo+3] = uint8(value)
+ value = floatToUint16(rgba[2] / sum)
+ out.Pix[xo+4] = uint8(value >> 8)
+ out.Pix[xo+5] = uint8(value)
+ value = floatToUint16(rgba[3] / sum)
+ out.Pix[xo+6] = uint8(value >> 8)
+ out.Pix[xo+7] = uint8(value)
+ }
+ }
+}
+
+func nearestNRGBA64(in *image.NRGBA64, out *image.NRGBA64, scale float64, coeffs []bool, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var rgba [4]float32
+ var sum float32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ if coeffs[ci+i] {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 8
+ case xi >= maxX:
+ xi = 8 * maxX
+ default:
+ xi = 0
+ }
+ rgba[0] += float32(uint16(row[xi+0])<<8 | uint16(row[xi+1]))
+ rgba[1] += float32(uint16(row[xi+2])<<8 | uint16(row[xi+3]))
+ rgba[2] += float32(uint16(row[xi+4])<<8 | uint16(row[xi+5]))
+ rgba[3] += float32(uint16(row[xi+6])<<8 | uint16(row[xi+7]))
+ sum++
+ }
+ }
+
+ xo := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*8
+ value := floatToUint16(rgba[0] / sum)
+ out.Pix[xo+0] = uint8(value >> 8)
+ out.Pix[xo+1] = uint8(value)
+ value = floatToUint16(rgba[1] / sum)
+ out.Pix[xo+2] = uint8(value >> 8)
+ out.Pix[xo+3] = uint8(value)
+ value = floatToUint16(rgba[2] / sum)
+ out.Pix[xo+4] = uint8(value >> 8)
+ out.Pix[xo+5] = uint8(value)
+ value = floatToUint16(rgba[3] / sum)
+ out.Pix[xo+6] = uint8(value >> 8)
+ out.Pix[xo+7] = uint8(value)
+ }
+ }
+}
+
+func nearestGray(in *image.Gray, out *image.Gray, scale float64, coeffs []bool, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var gray float32
+ var sum float32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ if coeffs[ci+i] {
+ xi := start + i
+ switch {
+ case xi < 0:
+ xi = 0
+ case xi >= maxX:
+ xi = maxX
+ }
+ gray += float32(row[xi])
+ sum++
+ }
+ }
+
+ offset := (y-newBounds.Min.Y)*out.Stride + (x - newBounds.Min.X)
+ out.Pix[offset] = floatToUint8(gray / sum)
+ }
+ }
+}
+
+func nearestGray16(in *image.Gray16, out *image.Gray16, scale float64, coeffs []bool, offset []int, filterLength int) {
+ newBounds := out.Bounds()
+ maxX := in.Bounds().Dx() - 1
+
+ for x := newBounds.Min.X; x < newBounds.Max.X; x++ {
+ row := in.Pix[x*in.Stride:]
+ for y := newBounds.Min.Y; y < newBounds.Max.Y; y++ {
+ var gray float32
+ var sum float32
+ start := offset[y]
+ ci := y * filterLength
+ for i := 0; i < filterLength; i++ {
+ if coeffs[ci+i] {
+ xi := start + i
+ switch {
+ case uint(xi) < uint(maxX):
+ xi *= 2
+ case xi >= maxX:
+ xi = 2 * maxX
+ default:
+ xi = 0
+ }
+ gray += float32(uint16(row[xi+0])<<8 | uint16(row[xi+1]))
+ sum++
+ }
+ }
+
+ offset := (y-newBounds.Min.Y)*out.Stride + (x-newBounds.Min.X)*2
+ value := floatToUint16(gray / sum)
+ out.Pix[offset+0] = uint8(value >> 8)
+ out.Pix[offset+1] = uint8(value)
+ }
+ }
+}
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/nearest_test.go b/Godeps/_workspace/src/github.com/nfnt/resize/nearest_test.go
new file mode 100644
index 000000000..d4a76dda5
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/nearest_test.go
@@ -0,0 +1,57 @@
+/*
+Copyright (c) 2014, Charlie Vieth <charlie.vieth@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 "testing"
+
+func Test_FloatToUint8(t *testing.T) {
+ var testData = []struct {
+ in float32
+ expected uint8
+ }{
+ {0, 0},
+ {255, 255},
+ {128, 128},
+ {1, 1},
+ {256, 255},
+ }
+ for _, test := range testData {
+ actual := floatToUint8(test.in)
+ if actual != test.expected {
+ t.Fail()
+ }
+ }
+}
+
+func Test_FloatToUint16(t *testing.T) {
+ var testData = []struct {
+ in float32
+ expected uint16
+ }{
+ {0, 0},
+ {65535, 65535},
+ {128, 128},
+ {1, 1},
+ {65536, 65535},
+ }
+ for _, test := range testData {
+ actual := floatToUint16(test.in)
+ if actual != test.expected {
+ t.Fail()
+ }
+ }
+}
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/resize.go b/Godeps/_workspace/src/github.com/nfnt/resize/resize.go
new file mode 100644
index 000000000..4d4ff6e3e
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/resize.go
@@ -0,0 +1,614 @@
+/*
+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 implements various image resizing methods.
+//
+// The package works with the Image interface described in the image package.
+// Various interpolation methods are provided and multiple processors may be
+// utilized in the computations.
+//
+// Example:
+// imgResized := resize.Resize(1000, 0, imgOld, resize.MitchellNetravali)
+package resize
+
+import (
+ "image"
+ "runtime"
+ "sync"
+)
+
+// An InterpolationFunction provides the parameters that describe an
+// interpolation kernel. It returns the number of samples to take
+// and the kernel function to use for sampling.
+type InterpolationFunction int
+
+// InterpolationFunction constants
+const (
+ // Nearest-neighbor interpolation
+ NearestNeighbor InterpolationFunction = iota
+ // Bilinear interpolation
+ Bilinear
+ // Bicubic interpolation (with cubic hermite spline)
+ Bicubic
+ // Mitchell-Netravali interpolation
+ MitchellNetravali
+ // Lanczos interpolation (a=2)
+ Lanczos2
+ // Lanczos interpolation (a=3)
+ Lanczos3
+)
+
+// kernal, returns an InterpolationFunctions taps and kernel.
+func (i InterpolationFunction) kernel() (int, func(float64) float64) {
+ switch i {
+ case Bilinear:
+ return 2, linear
+ case Bicubic:
+ return 4, cubic
+ case MitchellNetravali:
+ return 4, mitchellnetravali
+ case Lanczos2:
+ return 4, lanczos2
+ case Lanczos3:
+ return 6, lanczos3
+ default:
+ // Default to NearestNeighbor.
+ return 2, nearest
+ }
+}
+
+// values <1 will sharpen the image
+var blur = 1.0
+
+// Resize scales an image to new width and height using the interpolation function interp.
+// A new image with the given dimensions will be returned.
+// If one of the parameters width or height is set to 0, its size will be calculated so that
+// the aspect ratio is that of the originating image.
+// The resizing algorithm uses channels for parallel computation.
+func Resize(width, height uint, img image.Image, interp InterpolationFunction) image.Image {
+ scaleX, scaleY := calcFactors(width, height, float64(img.Bounds().Dx()), float64(img.Bounds().Dy()))
+ if width == 0 {
+ width = uint(0.7 + float64(img.Bounds().Dx())/scaleX)
+ }
+ if height == 0 {
+ height = uint(0.7 + float64(img.Bounds().Dy())/scaleY)
+ }
+
+ // Trivial case: return input image
+ if int(width) == img.Bounds().Dx() && int(height) == img.Bounds().Dy() {
+ return img
+ }
+
+ if interp == NearestNeighbor {
+ return resizeNearest(width, height, scaleX, scaleY, img, interp)
+ }
+
+ taps, kernel := interp.kernel()
+ cpus := runtime.GOMAXPROCS(0)
+ wg := sync.WaitGroup{}
+
+ // Generic access to image.Image is slow in tight loops.
+ // The optimal access has to be determined from the concrete image type.
+ switch input := img.(type) {
+ case *image.RGBA:
+ // 8-bit precision
+ temp := image.NewNRGBA(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewNRGBA(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeights8(temp.Bounds().Dy(), taps, blur, scaleX, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.NRGBA)
+ go func() {
+ defer wg.Done()
+ resizeRGBA(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeights8(result.Bounds().Dy(), taps, blur, scaleY, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.NRGBA)
+ go func() {
+ defer wg.Done()
+ resizeNRGBA(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ case *image.NRGBA:
+ // 8-bit precision
+ temp := image.NewNRGBA(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewNRGBA(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeights8(temp.Bounds().Dy(), taps, blur, scaleX, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.NRGBA)
+ go func() {
+ defer wg.Done()
+ resizeNRGBA(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeights8(result.Bounds().Dy(), taps, blur, scaleY, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.NRGBA)
+ go func() {
+ defer wg.Done()
+ resizeNRGBA(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+
+ case *image.YCbCr:
+ // 8-bit precision
+ // accessing the YCbCr arrays in a tight loop is slow.
+ // converting the image to ycc increases performance by 2x.
+ temp := newYCC(image.Rect(0, 0, input.Bounds().Dy(), int(width)), input.SubsampleRatio)
+ result := newYCC(image.Rect(0, 0, int(width), int(height)), input.SubsampleRatio)
+
+ coeffs, offset, filterLength := createWeights8(temp.Bounds().Dy(), taps, blur, scaleX, kernel)
+ in := imageYCbCrToYCC(input)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*ycc)
+ go func() {
+ defer wg.Done()
+ resizeYCbCr(in, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ coeffs, offset, filterLength = createWeights8(result.Bounds().Dy(), taps, blur, scaleY, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*ycc)
+ go func() {
+ defer wg.Done()
+ resizeYCbCr(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result.YCbCr()
+ case *image.RGBA64:
+ // 16-bit precision
+ temp := image.NewNRGBA64(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewNRGBA64(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeights16(temp.Bounds().Dy(), taps, blur, scaleX, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.NRGBA64)
+ go func() {
+ defer wg.Done()
+ resizeRGBA64(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeights16(result.Bounds().Dy(), taps, blur, scaleY, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.NRGBA64)
+ go func() {
+ defer wg.Done()
+ resizeNRGBA64(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ case *image.NRGBA64:
+ // 16-bit precision
+ temp := image.NewNRGBA64(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewNRGBA64(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeights16(temp.Bounds().Dy(), taps, blur, scaleX, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.NRGBA64)
+ go func() {
+ defer wg.Done()
+ resizeNRGBA64(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeights16(result.Bounds().Dy(), taps, blur, scaleY, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.NRGBA64)
+ go func() {
+ defer wg.Done()
+ resizeNRGBA64(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ case *image.Gray:
+ // 8-bit precision
+ temp := image.NewGray(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewGray(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeights8(temp.Bounds().Dy(), taps, blur, scaleX, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.Gray)
+ go func() {
+ defer wg.Done()
+ resizeGray(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeights8(result.Bounds().Dy(), taps, blur, scaleY, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.Gray)
+ go func() {
+ defer wg.Done()
+ resizeGray(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ case *image.Gray16:
+ // 16-bit precision
+ temp := image.NewGray16(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewGray16(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeights16(temp.Bounds().Dy(), taps, blur, scaleX, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.Gray16)
+ go func() {
+ defer wg.Done()
+ resizeGray16(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeights16(result.Bounds().Dy(), taps, blur, scaleY, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.Gray16)
+ go func() {
+ defer wg.Done()
+ resizeGray16(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ default:
+ // 16-bit precision
+ temp := image.NewNRGBA64(image.Rect(0, 0, img.Bounds().Dy(), int(width)))
+ result := image.NewNRGBA64(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeights16(temp.Bounds().Dy(), taps, blur, scaleX, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.NRGBA64)
+ go func() {
+ defer wg.Done()
+ resizeGeneric(img, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeights16(result.Bounds().Dy(), taps, blur, scaleY, kernel)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.NRGBA64)
+ go func() {
+ defer wg.Done()
+ resizeNRGBA64(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ }
+}
+
+func resizeNearest(width, height uint, scaleX, scaleY float64, img image.Image, interp InterpolationFunction) image.Image {
+ taps, _ := interp.kernel()
+ cpus := runtime.GOMAXPROCS(0)
+ wg := sync.WaitGroup{}
+
+ switch input := img.(type) {
+ case *image.RGBA:
+ // 8-bit precision
+ temp := image.NewRGBA(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewRGBA(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeightsNearest(temp.Bounds().Dy(), taps, blur, scaleX)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.RGBA)
+ go func() {
+ defer wg.Done()
+ nearestRGBA(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeightsNearest(result.Bounds().Dy(), taps, blur, scaleY)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.RGBA)
+ go func() {
+ defer wg.Done()
+ nearestRGBA(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ case *image.NRGBA:
+ // 8-bit precision
+ temp := image.NewNRGBA(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewNRGBA(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeightsNearest(temp.Bounds().Dy(), taps, blur, scaleX)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.NRGBA)
+ go func() {
+ defer wg.Done()
+ nearestNRGBA(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeightsNearest(result.Bounds().Dy(), taps, blur, scaleY)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.NRGBA)
+ go func() {
+ defer wg.Done()
+ nearestNRGBA(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ case *image.YCbCr:
+ // 8-bit precision
+ // accessing the YCbCr arrays in a tight loop is slow.
+ // converting the image to ycc increases performance by 2x.
+ temp := newYCC(image.Rect(0, 0, input.Bounds().Dy(), int(width)), input.SubsampleRatio)
+ result := newYCC(image.Rect(0, 0, int(width), int(height)), input.SubsampleRatio)
+
+ coeffs, offset, filterLength := createWeightsNearest(temp.Bounds().Dy(), taps, blur, scaleX)
+ in := imageYCbCrToYCC(input)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*ycc)
+ go func() {
+ defer wg.Done()
+ nearestYCbCr(in, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ coeffs, offset, filterLength = createWeightsNearest(result.Bounds().Dy(), taps, blur, scaleY)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*ycc)
+ go func() {
+ defer wg.Done()
+ nearestYCbCr(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result.YCbCr()
+ case *image.RGBA64:
+ // 16-bit precision
+ temp := image.NewRGBA64(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewRGBA64(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeightsNearest(temp.Bounds().Dy(), taps, blur, scaleX)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.RGBA64)
+ go func() {
+ defer wg.Done()
+ nearestRGBA64(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeightsNearest(result.Bounds().Dy(), taps, blur, scaleY)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.RGBA64)
+ go func() {
+ defer wg.Done()
+ nearestRGBA64(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ case *image.NRGBA64:
+ // 16-bit precision
+ temp := image.NewNRGBA64(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewNRGBA64(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeightsNearest(temp.Bounds().Dy(), taps, blur, scaleX)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.NRGBA64)
+ go func() {
+ defer wg.Done()
+ nearestNRGBA64(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeightsNearest(result.Bounds().Dy(), taps, blur, scaleY)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.NRGBA64)
+ go func() {
+ defer wg.Done()
+ nearestNRGBA64(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ case *image.Gray:
+ // 8-bit precision
+ temp := image.NewGray(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewGray(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeightsNearest(temp.Bounds().Dy(), taps, blur, scaleX)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.Gray)
+ go func() {
+ defer wg.Done()
+ nearestGray(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeightsNearest(result.Bounds().Dy(), taps, blur, scaleY)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.Gray)
+ go func() {
+ defer wg.Done()
+ nearestGray(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ case *image.Gray16:
+ // 16-bit precision
+ temp := image.NewGray16(image.Rect(0, 0, input.Bounds().Dy(), int(width)))
+ result := image.NewGray16(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeightsNearest(temp.Bounds().Dy(), taps, blur, scaleX)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.Gray16)
+ go func() {
+ defer wg.Done()
+ nearestGray16(input, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeightsNearest(result.Bounds().Dy(), taps, blur, scaleY)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.Gray16)
+ go func() {
+ defer wg.Done()
+ nearestGray16(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ default:
+ // 16-bit precision
+ temp := image.NewRGBA64(image.Rect(0, 0, img.Bounds().Dy(), int(width)))
+ result := image.NewRGBA64(image.Rect(0, 0, int(width), int(height)))
+
+ // horizontal filter, results in transposed temporary image
+ coeffs, offset, filterLength := createWeightsNearest(temp.Bounds().Dy(), taps, blur, scaleX)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(temp, i, cpus).(*image.RGBA64)
+ go func() {
+ defer wg.Done()
+ nearestGeneric(img, slice, scaleX, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+
+ // horizontal filter on transposed image, result is not transposed
+ coeffs, offset, filterLength = createWeightsNearest(result.Bounds().Dy(), taps, blur, scaleY)
+ wg.Add(cpus)
+ for i := 0; i < cpus; i++ {
+ slice := makeSlice(result, i, cpus).(*image.RGBA64)
+ go func() {
+ defer wg.Done()
+ nearestRGBA64(temp, slice, scaleY, coeffs, offset, filterLength)
+ }()
+ }
+ wg.Wait()
+ return result
+ }
+
+}
+
+// Calculates scaling factors using old and new image dimensions.
+func calcFactors(width, height uint, oldWidth, oldHeight float64) (scaleX, scaleY float64) {
+ if width == 0 {
+ if height == 0 {
+ scaleX = 1.0
+ scaleY = 1.0
+ } else {
+ scaleY = oldHeight / float64(height)
+ scaleX = scaleY
+ }
+ } else {
+ scaleX = oldWidth / float64(width)
+ if height == 0 {
+ scaleY = scaleX
+ } else {
+ scaleY = oldHeight / float64(height)
+ }
+ }
+ return
+}
+
+type imageWithSubImage interface {
+ image.Image
+ SubImage(image.Rectangle) image.Image
+}
+
+func makeSlice(img imageWithSubImage, i, n int) image.Image {
+ return img.SubImage(image.Rect(img.Bounds().Min.X, img.Bounds().Min.Y+i*img.Bounds().Dy()/n, img.Bounds().Max.X, img.Bounds().Min.Y+(i+1)*img.Bounds().Dy()/n))
+}
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/resize_test.go b/Godeps/_workspace/src/github.com/nfnt/resize/resize_test.go
new file mode 100644
index 000000000..ee31ac494
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/resize_test.go
@@ -0,0 +1,224 @@
+package resize
+
+import (
+ "image"
+ "image/color"
+ "runtime"
+ "testing"
+)
+
+var img = image.NewGray16(image.Rect(0, 0, 3, 3))
+
+func init() {
+ runtime.GOMAXPROCS(runtime.NumCPU())
+ img.Set(1, 1, color.White)
+}
+
+func Test_Param1(t *testing.T) {
+ m := Resize(0, 0, img, NearestNeighbor)
+ if m.Bounds() != img.Bounds() {
+ t.Fail()
+ }
+}
+
+func Test_Param2(t *testing.T) {
+ m := Resize(100, 0, img, NearestNeighbor)
+ if m.Bounds() != image.Rect(0, 0, 100, 100) {
+ t.Fail()
+ }
+}
+
+func Test_ZeroImg(t *testing.T) {
+ zeroImg := image.NewGray16(image.Rect(0, 0, 0, 0))
+
+ m := Resize(0, 0, zeroImg, NearestNeighbor)
+ if m.Bounds() != zeroImg.Bounds() {
+ t.Fail()
+ }
+}
+
+func Test_CorrectResize(t *testing.T) {
+ zeroImg := image.NewGray16(image.Rect(0, 0, 256, 256))
+
+ m := Resize(60, 0, zeroImg, NearestNeighbor)
+ if m.Bounds() != image.Rect(0, 0, 60, 60) {
+ t.Fail()
+ }
+}
+
+func Test_SameColor(t *testing.T) {
+ img := image.NewRGBA(image.Rect(0, 0, 20, 20))
+ for y := img.Bounds().Min.Y; y < img.Bounds().Max.Y; y++ {
+ for x := img.Bounds().Min.X; x < img.Bounds().Max.X; x++ {
+ img.SetRGBA(x, y, color.RGBA{0x80, 0x80, 0x80, 0xFF})
+ }
+ }
+ out := Resize(10, 10, img, Lanczos3)
+ for y := out.Bounds().Min.Y; y < out.Bounds().Max.Y; y++ {
+ for x := out.Bounds().Min.X; x < out.Bounds().Max.X; x++ {
+ color := img.At(x, y).(color.RGBA)
+ if color.R != 0x80 || color.G != 0x80 || color.B != 0x80 || color.A != 0xFF {
+ t.Fail()
+ }
+ }
+ }
+}
+
+func Test_Bounds(t *testing.T) {
+ img := image.NewRGBA(image.Rect(20, 10, 200, 99))
+ out := Resize(80, 80, img, Lanczos2)
+ out.At(0, 0)
+}
+
+func Test_SameSizeReturnsOriginal(t *testing.T) {
+ img := image.NewRGBA(image.Rect(0, 0, 10, 10))
+ out := Resize(0, 0, img, Lanczos2)
+
+ if img != out {
+ t.Fail()
+ }
+
+ out = Resize(10, 10, img, Lanczos2)
+
+ if img != out {
+ t.Fail()
+ }
+}
+
+func Test_PixelCoordinates(t *testing.T) {
+ checkers := image.NewGray(image.Rect(0, 0, 4, 4))
+ checkers.Pix = []uint8{
+ 255, 0, 255, 0,
+ 0, 255, 0, 255,
+ 255, 0, 255, 0,
+ 0, 255, 0, 255,
+ }
+
+ resized := Resize(12, 12, checkers, NearestNeighbor).(*image.Gray)
+
+ if resized.Pix[0] != 255 || resized.Pix[1] != 255 || resized.Pix[2] != 255 {
+ t.Fail()
+ }
+
+ if resized.Pix[3] != 0 || resized.Pix[4] != 0 || resized.Pix[5] != 0 {
+ t.Fail()
+ }
+}
+
+func Test_ResizeWithPremultipliedAlpha(t *testing.T) {
+ img := image.NewRGBA(image.Rect(0, 0, 1, 4))
+ for y := img.Bounds().Min.Y; y < img.Bounds().Max.Y; y++ {
+ // 0x80 = 0.5 * 0xFF.
+ img.SetRGBA(0, y, color.RGBA{0x80, 0x80, 0x80, 0x80})
+ }
+
+ out := Resize(1, 2, img, MitchellNetravali)
+
+ outputColor := out.At(0, 0).(color.NRGBA)
+ if outputColor.R != 0xFF {
+ t.Fail()
+ }
+}
+
+const (
+ // Use a small image size for benchmarks. We don't want memory performance
+ // to affect the benchmark results.
+ benchMaxX = 250
+ benchMaxY = 250
+
+ // Resize values near the original size require increase the amount of time
+ // resize spends converting the image.
+ benchWidth = 200
+ benchHeight = 200
+)
+
+func benchRGBA(b *testing.B, interp InterpolationFunction) {
+ m := image.NewRGBA(image.Rect(0, 0, benchMaxX, benchMaxY))
+ // Initialize m's pixels to create a non-uniform image.
+ for y := m.Rect.Min.Y; y < m.Rect.Max.Y; y++ {
+ for x := m.Rect.Min.X; x < m.Rect.Max.X; x++ {
+ i := m.PixOffset(x, y)
+ m.Pix[i+0] = uint8(y + 4*x)
+ m.Pix[i+1] = uint8(y + 4*x)
+ m.Pix[i+2] = uint8(y + 4*x)
+ m.Pix[i+3] = uint8(4*y + x)
+ }
+ }
+
+ var out image.Image
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ out = Resize(benchWidth, benchHeight, m, interp)
+ }
+ out.At(0, 0)
+}
+
+// The names of some interpolation functions are truncated so that the columns
+// of 'go test -bench' line up.
+func Benchmark_Nearest_RGBA(b *testing.B) {
+ benchRGBA(b, NearestNeighbor)
+}
+
+func Benchmark_Bilinear_RGBA(b *testing.B) {
+ benchRGBA(b, Bilinear)
+}
+
+func Benchmark_Bicubic_RGBA(b *testing.B) {
+ benchRGBA(b, Bicubic)
+}
+
+func Benchmark_Mitchell_RGBA(b *testing.B) {
+ benchRGBA(b, MitchellNetravali)
+}
+
+func Benchmark_Lanczos2_RGBA(b *testing.B) {
+ benchRGBA(b, Lanczos2)
+}
+
+func Benchmark_Lanczos3_RGBA(b *testing.B) {
+ benchRGBA(b, Lanczos3)
+}
+
+func benchYCbCr(b *testing.B, interp InterpolationFunction) {
+ m := image.NewYCbCr(image.Rect(0, 0, benchMaxX, benchMaxY), image.YCbCrSubsampleRatio422)
+ // Initialize m's pixels to create a non-uniform image.
+ for y := m.Rect.Min.Y; y < m.Rect.Max.Y; y++ {
+ for x := m.Rect.Min.X; x < m.Rect.Max.X; x++ {
+ yi := m.YOffset(x, y)
+ ci := m.COffset(x, y)
+ m.Y[yi] = uint8(16*y + x)
+ m.Cb[ci] = uint8(y + 16*x)
+ m.Cr[ci] = uint8(y + 16*x)
+ }
+ }
+ var out image.Image
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ out = Resize(benchWidth, benchHeight, m, interp)
+ }
+ out.At(0, 0)
+}
+
+func Benchmark_Nearest_YCC(b *testing.B) {
+ benchYCbCr(b, NearestNeighbor)
+}
+
+func Benchmark_Bilinear_YCC(b *testing.B) {
+ benchYCbCr(b, Bilinear)
+}
+
+func Benchmark_Bicubic_YCC(b *testing.B) {
+ benchYCbCr(b, Bicubic)
+}
+
+func Benchmark_Mitchell_YCC(b *testing.B) {
+ benchYCbCr(b, MitchellNetravali)
+}
+
+func Benchmark_Lanczos2_YCC(b *testing.B) {
+ benchYCbCr(b, Lanczos2)
+}
+
+func Benchmark_Lanczos3_YCC(b *testing.B) {
+ benchYCbCr(b, Lanczos3)
+}
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/thumbnail.go b/Godeps/_workspace/src/github.com/nfnt/resize/thumbnail.go
new file mode 100644
index 000000000..9efc246be
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/thumbnail.go
@@ -0,0 +1,55 @@
+/*
+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)
+}
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/thumbnail_test.go b/Godeps/_workspace/src/github.com/nfnt/resize/thumbnail_test.go
new file mode 100644
index 000000000..bd9875b2b
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/thumbnail_test.go
@@ -0,0 +1,47 @@
+package resize
+
+import (
+ "image"
+ "runtime"
+ "testing"
+)
+
+func init() {
+ runtime.GOMAXPROCS(runtime.NumCPU())
+}
+
+var thumbnailTests = []struct {
+ origWidth int
+ origHeight int
+ maxWidth uint
+ maxHeight uint
+ expectedWidth uint
+ expectedHeight uint
+}{
+ {5, 5, 10, 10, 5, 5},
+ {10, 10, 5, 5, 5, 5},
+ {10, 50, 10, 10, 2, 10},
+ {50, 10, 10, 10, 10, 2},
+ {50, 100, 60, 90, 45, 90},
+ {120, 100, 60, 90, 60, 50},
+ {200, 250, 200, 150, 120, 150},
+}
+
+func TestThumbnail(t *testing.T) {
+ for i, tt := range thumbnailTests {
+ img := image.NewGray16(image.Rect(0, 0, tt.origWidth, tt.origHeight))
+
+ outImg := Thumbnail(tt.maxWidth, tt.maxHeight, img, NearestNeighbor)
+
+ newWidth := uint(outImg.Bounds().Dx())
+ newHeight := uint(outImg.Bounds().Dy())
+ if newWidth != tt.expectedWidth ||
+ newHeight != tt.expectedHeight {
+ t.Errorf("%d. Thumbnail(%v, %v, img, NearestNeighbor) => "+
+ "width: %v, height: %v, want width: %v, height: %v",
+ i, tt.maxWidth, tt.maxHeight,
+ newWidth, newHeight, tt.expectedWidth, tt.expectedHeight,
+ )
+ }
+ }
+}
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/ycc.go b/Godeps/_workspace/src/github.com/nfnt/resize/ycc.go
new file mode 100644
index 000000000..104159955
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/ycc.go
@@ -0,0 +1,227 @@
+/*
+Copyright (c) 2014, Charlie Vieth <charlie.vieth@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"
+ "image/color"
+)
+
+// ycc is an in memory YCbCr image. The Y, Cb and Cr samples are held in a
+// single slice to increase resizing performance.
+type ycc struct {
+ // Pix holds the image's pixels, in Y, Cb, Cr order. The pixel at
+ // (x, y) starts at Pix[(y-Rect.Min.Y)*Stride + (x-Rect.Min.X)*3].
+ Pix []uint8
+ // Stride is the Pix stride (in bytes) between vertically adjacent pixels.
+ Stride int
+ // Rect is the image's bounds.
+ Rect image.Rectangle
+ // SubsampleRatio is the subsample ratio of the original YCbCr image.
+ SubsampleRatio image.YCbCrSubsampleRatio
+}
+
+// PixOffset returns the index of the first element of Pix that corresponds to
+// the pixel at (x, y).
+func (p *ycc) PixOffset(x, y int) int {
+ return (y-p.Rect.Min.Y)*p.Stride + (x-p.Rect.Min.X)*3
+}
+
+func (p *ycc) Bounds() image.Rectangle {
+ return p.Rect
+}
+
+func (p *ycc) ColorModel() color.Model {
+ return color.YCbCrModel
+}
+
+func (p *ycc) At(x, y int) color.Color {
+ if !(image.Point{x, y}.In(p.Rect)) {
+ return color.YCbCr{}
+ }
+ i := p.PixOffset(x, y)
+ return color.YCbCr{
+ p.Pix[i+0],
+ p.Pix[i+1],
+ p.Pix[i+2],
+ }
+}
+
+func (p *ycc) Opaque() bool {
+ return true
+}
+
+// SubImage returns an image representing the portion of the image p visible
+// through r. The returned value shares pixels with the original image.
+func (p *ycc) SubImage(r image.Rectangle) image.Image {
+ r = r.Intersect(p.Rect)
+ if r.Empty() {
+ return &ycc{SubsampleRatio: p.SubsampleRatio}
+ }
+ i := p.PixOffset(r.Min.X, r.Min.Y)
+ return &ycc{
+ Pix: p.Pix[i:],
+ Stride: p.Stride,
+ Rect: r,
+ SubsampleRatio: p.SubsampleRatio,
+ }
+}
+
+// newYCC returns a new ycc with the given bounds and subsample ratio.
+func newYCC(r image.Rectangle, s image.YCbCrSubsampleRatio) *ycc {
+ w, h := r.Dx(), r.Dy()
+ buf := make([]uint8, 3*w*h)
+ return &ycc{Pix: buf, Stride: 3 * w, Rect: r, SubsampleRatio: s}
+}
+
+// YCbCr converts ycc to a YCbCr image with the same subsample ratio
+// as the YCbCr image that ycc was generated from.
+func (p *ycc) YCbCr() *image.YCbCr {
+ ycbcr := image.NewYCbCr(p.Rect, p.SubsampleRatio)
+ var off int
+
+ switch ycbcr.SubsampleRatio {
+ case image.YCbCrSubsampleRatio422:
+ for y := ycbcr.Rect.Min.Y; y < ycbcr.Rect.Max.Y; y++ {
+ yy := (y - ycbcr.Rect.Min.Y) * ycbcr.YStride
+ cy := (y - ycbcr.Rect.Min.Y) * ycbcr.CStride
+ for x := ycbcr.Rect.Min.X; x < ycbcr.Rect.Max.X; x++ {
+ xx := (x - ycbcr.Rect.Min.X)
+ yi := yy + xx
+ ci := cy + xx/2
+ ycbcr.Y[yi] = p.Pix[off+0]
+ ycbcr.Cb[ci] = p.Pix[off+1]
+ ycbcr.Cr[ci] = p.Pix[off+2]
+ off += 3
+ }
+ }
+ case image.YCbCrSubsampleRatio420:
+ for y := ycbcr.Rect.Min.Y; y < ycbcr.Rect.Max.Y; y++ {
+ yy := (y - ycbcr.Rect.Min.Y) * ycbcr.YStride
+ cy := (y/2 - ycbcr.Rect.Min.Y/2) * ycbcr.CStride
+ for x := ycbcr.Rect.Min.X; x < ycbcr.Rect.Max.X; x++ {
+ xx := (x - ycbcr.Rect.Min.X)
+ yi := yy + xx
+ ci := cy + xx/2
+ ycbcr.Y[yi] = p.Pix[off+0]
+ ycbcr.Cb[ci] = p.Pix[off+1]
+ ycbcr.Cr[ci] = p.Pix[off+2]
+ off += 3
+ }
+ }
+ case image.YCbCrSubsampleRatio440:
+ for y := ycbcr.Rect.Min.Y; y < ycbcr.Rect.Max.Y; y++ {
+ yy := (y - ycbcr.Rect.Min.Y) * ycbcr.YStride
+ cy := (y/2 - ycbcr.Rect.Min.Y/2) * ycbcr.CStride
+ for x := ycbcr.Rect.Min.X; x < ycbcr.Rect.Max.X; x++ {
+ xx := (x - ycbcr.Rect.Min.X)
+ yi := yy + xx
+ ci := cy + xx
+ ycbcr.Y[yi] = p.Pix[off+0]
+ ycbcr.Cb[ci] = p.Pix[off+1]
+ ycbcr.Cr[ci] = p.Pix[off+2]
+ off += 3
+ }
+ }
+ default:
+ // Default to 4:4:4 subsampling.
+ for y := ycbcr.Rect.Min.Y; y < ycbcr.Rect.Max.Y; y++ {
+ yy := (y - ycbcr.Rect.Min.Y) * ycbcr.YStride
+ cy := (y - ycbcr.Rect.Min.Y) * ycbcr.CStride
+ for x := ycbcr.Rect.Min.X; x < ycbcr.Rect.Max.X; x++ {
+ xx := (x - ycbcr.Rect.Min.X)
+ yi := yy + xx
+ ci := cy + xx
+ ycbcr.Y[yi] = p.Pix[off+0]
+ ycbcr.Cb[ci] = p.Pix[off+1]
+ ycbcr.Cr[ci] = p.Pix[off+2]
+ off += 3
+ }
+ }
+ }
+ return ycbcr
+}
+
+// imageYCbCrToYCC converts a YCbCr image to a ycc image for resizing.
+func imageYCbCrToYCC(in *image.YCbCr) *ycc {
+ w, h := in.Rect.Dx(), in.Rect.Dy()
+ r := image.Rect(0, 0, w, h)
+ buf := make([]uint8, 3*w*h)
+ p := ycc{Pix: buf, Stride: 3 * w, Rect: r, SubsampleRatio: in.SubsampleRatio}
+ var off int
+
+ switch in.SubsampleRatio {
+ case image.YCbCrSubsampleRatio422:
+ for y := in.Rect.Min.Y; y < in.Rect.Max.Y; y++ {
+ yy := (y - in.Rect.Min.Y) * in.YStride
+ cy := (y - in.Rect.Min.Y) * in.CStride
+ for x := in.Rect.Min.X; x < in.Rect.Max.X; x++ {
+ xx := (x - in.Rect.Min.X)
+ yi := yy + xx
+ ci := cy + xx/2
+ p.Pix[off+0] = in.Y[yi]
+ p.Pix[off+1] = in.Cb[ci]
+ p.Pix[off+2] = in.Cr[ci]
+ off += 3
+ }
+ }
+ case image.YCbCrSubsampleRatio420:
+ for y := in.Rect.Min.Y; y < in.Rect.Max.Y; y++ {
+ yy := (y - in.Rect.Min.Y) * in.YStride
+ cy := (y/2 - in.Rect.Min.Y/2) * in.CStride
+ for x := in.Rect.Min.X; x < in.Rect.Max.X; x++ {
+ xx := (x - in.Rect.Min.X)
+ yi := yy + xx
+ ci := cy + xx/2
+ p.Pix[off+0] = in.Y[yi]
+ p.Pix[off+1] = in.Cb[ci]
+ p.Pix[off+2] = in.Cr[ci]
+ off += 3
+ }
+ }
+ case image.YCbCrSubsampleRatio440:
+ for y := in.Rect.Min.Y; y < in.Rect.Max.Y; y++ {
+ yy := (y - in.Rect.Min.Y) * in.YStride
+ cy := (y/2 - in.Rect.Min.Y/2) * in.CStride
+ for x := in.Rect.Min.X; x < in.Rect.Max.X; x++ {
+ xx := (x - in.Rect.Min.X)
+ yi := yy + xx
+ ci := cy + xx
+ p.Pix[off+0] = in.Y[yi]
+ p.Pix[off+1] = in.Cb[ci]
+ p.Pix[off+2] = in.Cr[ci]
+ off += 3
+ }
+ }
+ default:
+ // Default to 4:4:4 subsampling.
+ for y := in.Rect.Min.Y; y < in.Rect.Max.Y; y++ {
+ yy := (y - in.Rect.Min.Y) * in.YStride
+ cy := (y - in.Rect.Min.Y) * in.CStride
+ for x := in.Rect.Min.X; x < in.Rect.Max.X; x++ {
+ xx := (x - in.Rect.Min.X)
+ yi := yy + xx
+ ci := cy + xx
+ p.Pix[off+0] = in.Y[yi]
+ p.Pix[off+1] = in.Cb[ci]
+ p.Pix[off+2] = in.Cr[ci]
+ off += 3
+ }
+ }
+ }
+ return &p
+}
diff --git a/Godeps/_workspace/src/github.com/nfnt/resize/ycc_test.go b/Godeps/_workspace/src/github.com/nfnt/resize/ycc_test.go
new file mode 100644
index 000000000..54d53d157
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/nfnt/resize/ycc_test.go
@@ -0,0 +1,214 @@
+/*
+Copyright (c) 2014, Charlie Vieth <charlie.vieth@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"
+ "image/color"
+ "testing"
+)
+
+type Image interface {
+ image.Image
+ SubImage(image.Rectangle) image.Image
+}
+
+func TestImage(t *testing.T) {
+ testImage := []Image{
+ newYCC(image.Rect(0, 0, 10, 10), image.YCbCrSubsampleRatio420),
+ newYCC(image.Rect(0, 0, 10, 10), image.YCbCrSubsampleRatio422),
+ newYCC(image.Rect(0, 0, 10, 10), image.YCbCrSubsampleRatio440),
+ newYCC(image.Rect(0, 0, 10, 10), image.YCbCrSubsampleRatio444),
+ }
+ for _, m := range testImage {
+ if !image.Rect(0, 0, 10, 10).Eq(m.Bounds()) {
+ t.Errorf("%T: want bounds %v, got %v",
+ m, image.Rect(0, 0, 10, 10), m.Bounds())
+ continue
+ }
+ m = m.SubImage(image.Rect(3, 2, 9, 8)).(Image)
+ if !image.Rect(3, 2, 9, 8).Eq(m.Bounds()) {
+ t.Errorf("%T: sub-image want bounds %v, got %v",
+ m, image.Rect(3, 2, 9, 8), m.Bounds())
+ continue
+ }
+ // Test that taking an empty sub-image starting at a corner does not panic.
+ m.SubImage(image.Rect(0, 0, 0, 0))
+ m.SubImage(image.Rect(10, 0, 10, 0))
+ m.SubImage(image.Rect(0, 10, 0, 10))
+ m.SubImage(image.Rect(10, 10, 10, 10))
+ }
+}
+
+func TestConvertYCbCr(t *testing.T) {
+ testImage := []Image{
+ image.NewYCbCr(image.Rect(0, 0, 50, 50), image.YCbCrSubsampleRatio420),
+ image.NewYCbCr(image.Rect(0, 0, 50, 50), image.YCbCrSubsampleRatio422),
+ image.NewYCbCr(image.Rect(0, 0, 50, 50), image.YCbCrSubsampleRatio440),
+ image.NewYCbCr(image.Rect(0, 0, 50, 50), image.YCbCrSubsampleRatio444),
+ }
+
+ for _, img := range testImage {
+ m := img.(*image.YCbCr)
+ for y := m.Rect.Min.Y; y < m.Rect.Max.Y; y++ {
+ for x := m.Rect.Min.X; x < m.Rect.Max.X; x++ {
+ yi := m.YOffset(x, y)
+ ci := m.COffset(x, y)
+ m.Y[yi] = uint8(16*y + x)
+ m.Cb[ci] = uint8(y + 16*x)
+ m.Cr[ci] = uint8(y + 16*x)
+ }
+ }
+
+ // test conversion from YCbCr to ycc
+ yc := imageYCbCrToYCC(m)
+ for y := m.Rect.Min.Y; y < m.Rect.Max.Y; y++ {
+ for x := m.Rect.Min.X; x < m.Rect.Max.X; x++ {
+ ystride := 3 * (m.Rect.Max.X - m.Rect.Min.X)
+ xstride := 3
+ yi := m.YOffset(x, y)
+ ci := m.COffset(x, y)
+ si := (y * ystride) + (x * xstride)
+ if m.Y[yi] != yc.Pix[si] {
+ t.Errorf("Err Y - found: %d expected: %d x: %d y: %d yi: %d si: %d",
+ m.Y[yi], yc.Pix[si], x, y, yi, si)
+ }
+ if m.Cb[ci] != yc.Pix[si+1] {
+ t.Errorf("Err Cb - found: %d expected: %d x: %d y: %d ci: %d si: %d",
+ m.Cb[ci], yc.Pix[si+1], x, y, ci, si+1)
+ }
+ if m.Cr[ci] != yc.Pix[si+2] {
+ t.Errorf("Err Cr - found: %d expected: %d x: %d y: %d ci: %d si: %d",
+ m.Cr[ci], yc.Pix[si+2], x, y, ci, si+2)
+ }
+ }
+ }
+
+ // test conversion from ycc back to YCbCr
+ ym := yc.YCbCr()
+ for y := m.Rect.Min.Y; y < m.Rect.Max.Y; y++ {
+ for x := m.Rect.Min.X; x < m.Rect.Max.X; x++ {
+ yi := m.YOffset(x, y)
+ ci := m.COffset(x, y)
+ if m.Y[yi] != ym.Y[yi] {
+ t.Errorf("Err Y - found: %d expected: %d x: %d y: %d yi: %d",
+ m.Y[yi], ym.Y[yi], x, y, yi)
+ }
+ if m.Cb[ci] != ym.Cb[ci] {
+ t.Errorf("Err Cb - found: %d expected: %d x: %d y: %d ci: %d",
+ m.Cb[ci], ym.Cb[ci], x, y, ci)
+ }
+ if m.Cr[ci] != ym.Cr[ci] {
+ t.Errorf("Err Cr - found: %d expected: %d x: %d y: %d ci: %d",
+ m.Cr[ci], ym.Cr[ci], x, y, ci)
+ }
+ }
+ }
+ }
+}
+
+func TestYCbCr(t *testing.T) {
+ rects := []image.Rectangle{
+ image.Rect(0, 0, 16, 16),
+ image.Rect(1, 0, 16, 16),
+ image.Rect(0, 1, 16, 16),
+ image.Rect(1, 1, 16, 16),
+ image.Rect(1, 1, 15, 16),
+ image.Rect(1, 1, 16, 15),
+ image.Rect(1, 1, 15, 15),
+ image.Rect(2, 3, 14, 15),
+ image.Rect(7, 0, 7, 16),
+ image.Rect(0, 8, 16, 8),
+ image.Rect(0, 0, 10, 11),
+ image.Rect(5, 6, 16, 16),
+ image.Rect(7, 7, 8, 8),
+ image.Rect(7, 8, 8, 9),
+ image.Rect(8, 7, 9, 8),
+ image.Rect(8, 8, 9, 9),
+ image.Rect(7, 7, 17, 17),
+ image.Rect(8, 8, 17, 17),
+ image.Rect(9, 9, 17, 17),
+ image.Rect(10, 10, 17, 17),
+ }
+ subsampleRatios := []image.YCbCrSubsampleRatio{
+ image.YCbCrSubsampleRatio444,
+ image.YCbCrSubsampleRatio422,
+ image.YCbCrSubsampleRatio420,
+ image.YCbCrSubsampleRatio440,
+ }
+ deltas := []image.Point{
+ image.Pt(0, 0),
+ image.Pt(1000, 1001),
+ image.Pt(5001, -400),
+ image.Pt(-701, -801),
+ }
+ for _, r := range rects {
+ for _, subsampleRatio := range subsampleRatios {
+ for _, delta := range deltas {
+ testYCbCr(t, r, subsampleRatio, delta)
+ }
+ }
+ if testing.Short() {
+ break
+ }
+ }
+}
+
+func testYCbCr(t *testing.T, r image.Rectangle, subsampleRatio image.YCbCrSubsampleRatio, delta image.Point) {
+ // Create a YCbCr image m, whose bounds are r translated by (delta.X, delta.Y).
+ r1 := r.Add(delta)
+ img := image.NewYCbCr(r1, subsampleRatio)
+
+ // Initialize img's pixels. For 422 and 420 subsampling, some of the Cb and Cr elements
+ // will be set multiple times. That's OK. We just want to avoid a uniform image.
+ for y := r1.Min.Y; y < r1.Max.Y; y++ {
+ for x := r1.Min.X; x < r1.Max.X; x++ {
+ yi := img.YOffset(x, y)
+ ci := img.COffset(x, y)
+ img.Y[yi] = uint8(16*y + x)
+ img.Cb[ci] = uint8(y + 16*x)
+ img.Cr[ci] = uint8(y + 16*x)
+ }
+ }
+
+ m := imageYCbCrToYCC(img)
+
+ // Make various sub-images of m.
+ for y0 := delta.Y + 3; y0 < delta.Y+7; y0++ {
+ for y1 := delta.Y + 8; y1 < delta.Y+13; y1++ {
+ for x0 := delta.X + 3; x0 < delta.X+7; x0++ {
+ for x1 := delta.X + 8; x1 < delta.X+13; x1++ {
+ subRect := image.Rect(x0, y0, x1, y1)
+ sub := m.SubImage(subRect).(*ycc)
+
+ // For each point in the sub-image's bounds, check that m.At(x, y) equals sub.At(x, y).
+ for y := sub.Rect.Min.Y; y < sub.Rect.Max.Y; y++ {
+ for x := sub.Rect.Min.X; x < sub.Rect.Max.X; x++ {
+ color0 := m.At(x, y).(color.YCbCr)
+ color1 := sub.At(x, y).(color.YCbCr)
+ if color0 != color1 {
+ t.Errorf("r=%v, subsampleRatio=%v, delta=%v, x=%d, y=%d, color0=%v, color1=%v",
+ r, subsampleRatio, delta, x, y, color0, color1)
+ return
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+}