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path: root/Godeps/_workspace/src/github.com/nfnt/resize/converter.go
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Diffstat (limited to 'Godeps/_workspace/src/github.com/nfnt/resize/converter.go')
-rw-r--r--Godeps/_workspace/src/github.com/nfnt/resize/converter.go452
1 files changed, 452 insertions, 0 deletions
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)
+ }
+ }
+}
generated by cgit v1.2.3-1-g7c22 (git 2.25.1) at 2024-06-16 17:37:38 +0000