diff options
Diffstat (limited to 'vendor/github.com/disintegration/imaging')
| -rw-r--r-- | vendor/github.com/disintegration/imaging/.travis.yml | 13 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/LICENSE | 21 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/README.md | 188 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/adjust.go | 222 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/convolution.go | 146 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/doc.go | 7 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/effects.go | 165 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/helpers.go | 280 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/histogram.go | 51 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/resize.go | 572 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/scanner.go | 250 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/tools.go | 213 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/transform.go | 271 | ||||
| -rw-r--r-- | vendor/github.com/disintegration/imaging/utils.go | 83 |
14 files changed, 2482 insertions, 0 deletions
diff --git a/vendor/github.com/disintegration/imaging/.travis.yml b/vendor/github.com/disintegration/imaging/.travis.yml new file mode 100644 index 0000000..89370ed --- /dev/null +++ b/vendor/github.com/disintegration/imaging/.travis.yml @@ -0,0 +1,13 @@ +language: go +go: + - "1.7.x" + - "1.8.x" + - "1.9.x" + - "1.10.x" + +before_install: + - go get github.com/mattn/goveralls + +script: + - go test -v -race -cover + - $GOPATH/bin/goveralls -service=travis-ci diff --git a/vendor/github.com/disintegration/imaging/LICENSE b/vendor/github.com/disintegration/imaging/LICENSE new file mode 100644 index 0000000..c68f7ab --- /dev/null +++ b/vendor/github.com/disintegration/imaging/LICENSE @@ -0,0 +1,21 @@ +The MIT License (MIT) + +Copyright (c) 2012-2018 Grigory Dryapak + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE.
\ No newline at end of file diff --git a/vendor/github.com/disintegration/imaging/README.md b/vendor/github.com/disintegration/imaging/README.md new file mode 100644 index 0000000..c7ee30f --- /dev/null +++ b/vendor/github.com/disintegration/imaging/README.md @@ -0,0 +1,188 @@ +# Imaging
+
+[](https://godoc.org/github.com/disintegration/imaging)
+[](https://travis-ci.org/disintegration/imaging)
+[](https://coveralls.io/github/disintegration/imaging?branch=master)
+[](https://goreportcard.com/report/github.com/disintegration/imaging)
+
+Package imaging provides basic image processing functions (resize, rotate, crop, brightness/contrast adjustments, etc.).
+
+All the image processing functions provided by the package accept any image type that implements `image.Image` interface
+as an input, and return a new image of `*image.NRGBA` type (32bit RGBA colors, not premultiplied by alpha).
+
+## Installation
+
+ go get -u github.com/disintegration/imaging
+
+## Documentation
+
+http://godoc.org/github.com/disintegration/imaging
+
+## Usage examples
+
+A few usage examples can be found below. See the documentation for the full list of supported functions.
+
+### Image resizing
+
+```go
+// Resize srcImage to size = 128x128px using the Lanczos filter.
+dstImage128 := imaging.Resize(srcImage, 128, 128, imaging.Lanczos)
+
+// Resize srcImage to width = 800px preserving the aspect ratio.
+dstImage800 := imaging.Resize(srcImage, 800, 0, imaging.Lanczos)
+
+// Scale down srcImage to fit the 800x600px bounding box.
+dstImageFit := imaging.Fit(srcImage, 800, 600, imaging.Lanczos)
+
+// Resize and crop the srcImage to fill the 100x100px area.
+dstImageFill := imaging.Fill(srcImage, 100, 100, imaging.Center, imaging.Lanczos)
+```
+
+Imaging supports image resizing using various resampling filters. The most notable ones:
+- `NearestNeighbor` - Fastest resampling filter, no antialiasing.
+- `Box` - Simple and fast averaging filter appropriate for downscaling. When upscaling it's similar to NearestNeighbor.
+- `Linear` - Bilinear filter, smooth and reasonably fast.
+- `MitchellNetravali` - А smooth bicubic filter.
+- `CatmullRom` - A sharp bicubic filter.
+- `Gaussian` - Blurring filter that uses gaussian function, useful for noise removal.
+- `Lanczos` - High-quality resampling filter for photographic images yielding sharp results, slower than cubic filters.
+
+The full list of supported filters: NearestNeighbor, Box, Linear, Hermite, MitchellNetravali, CatmullRom, BSpline, Gaussian, Lanczos, Hann, Hamming, Blackman, Bartlett, Welch, Cosine. Custom filters can be created using ResampleFilter struct.
+
+**Resampling filters comparison**
+
+Original image:
+
+
+
+The same image resized from 600x400px to 150x100px using different resampling filters.
+From faster (lower quality) to slower (higher quality):
+
+Filter | Resize result
+--------------------------|---------------------------------------------
+`imaging.NearestNeighbor` | 
+`imaging.Linear` | 
+`imaging.CatmullRom` | 
+`imaging.Lanczos` | 
+
+
+### Gaussian Blur
+
+```go
+dstImage := imaging.Blur(srcImage, 0.5)
+```
+
+Sigma parameter allows to control the strength of the blurring effect.
+
+Original image | Sigma = 0.5 | Sigma = 1.5
+-----------------------------------|----------------------------------------|---------------------------------------
+ |  | 
+
+### Sharpening
+
+```go
+dstImage := imaging.Sharpen(srcImage, 0.5)
+```
+
+`Sharpen` uses gaussian function internally. Sigma parameter allows to control the strength of the sharpening effect.
+
+Original image | Sigma = 0.5 | Sigma = 1.5
+-----------------------------------|-------------------------------------------|------------------------------------------
+ |  | 
+
+### Gamma correction
+
+```go
+dstImage := imaging.AdjustGamma(srcImage, 0.75)
+```
+
+Original image | Gamma = 0.75 | Gamma = 1.25
+-----------------------------------|------------------------------------------|-----------------------------------------
+ |  | 
+
+### Contrast adjustment
+
+```go
+dstImage := imaging.AdjustContrast(srcImage, 20)
+```
+
+Original image | Contrast = 15 | Contrast = -15
+-----------------------------------|--------------------------------------------|-------------------------------------------
+ |  | 
+
+### Brightness adjustment
+
+```go
+dstImage := imaging.AdjustBrightness(srcImage, 20)
+```
+
+Original image | Brightness = 10 | Brightness = -10
+-----------------------------------|----------------------------------------------|---------------------------------------------
+ |  | 
+
+## Example code
+
+```go
+package main
+
+import (
+ "image"
+ "image/color"
+ "log"
+
+ "github.com/disintegration/imaging"
+)
+
+func main() {
+ // Open a test image.
+ src, err := imaging.Open("testdata/flowers.png")
+ if err != nil {
+ log.Fatalf("failed to open image: %v", err)
+ }
+
+ // Crop the original image to 300x300px size using the center anchor.
+ src = imaging.CropAnchor(src, 300, 300, imaging.Center)
+
+ // Resize the cropped image to width = 200px preserving the aspect ratio.
+ src = imaging.Resize(src, 200, 0, imaging.Lanczos)
+
+ // Create a blurred version of the image.
+ img1 := imaging.Blur(src, 5)
+
+ // Create a grayscale version of the image with higher contrast and sharpness.
+ img2 := imaging.Grayscale(src)
+ img2 = imaging.AdjustContrast(img2, 20)
+ img2 = imaging.Sharpen(img2, 2)
+
+ // Create an inverted version of the image.
+ img3 := imaging.Invert(src)
+
+ // Create an embossed version of the image using a convolution filter.
+ img4 := imaging.Convolve3x3(
+ src,
+ [9]float64{
+ -1, -1, 0,
+ -1, 1, 1,
+ 0, 1, 1,
+ },
+ nil,
+ )
+
+ // Create a new image and paste the four produced images into it.
+ dst := imaging.New(400, 400, color.NRGBA{0, 0, 0, 0})
+ dst = imaging.Paste(dst, img1, image.Pt(0, 0))
+ dst = imaging.Paste(dst, img2, image.Pt(0, 200))
+ dst = imaging.Paste(dst, img3, image.Pt(200, 0))
+ dst = imaging.Paste(dst, img4, image.Pt(200, 200))
+
+ // Save the resulting image as JPEG.
+ err = imaging.Save(dst, "testdata/out_example.jpg")
+ if err != nil {
+ log.Fatalf("failed to save image: %v", err)
+ }
+}
+```
+
+Output:
+
+
\ No newline at end of file diff --git a/vendor/github.com/disintegration/imaging/adjust.go b/vendor/github.com/disintegration/imaging/adjust.go new file mode 100644 index 0000000..fb3a9ce --- /dev/null +++ b/vendor/github.com/disintegration/imaging/adjust.go @@ -0,0 +1,222 @@ +package imaging + +import ( + "image" + "image/color" + "math" +) + +// Grayscale produces a grayscale version of the image. +func Grayscale(img image.Image) *image.NRGBA { + src := newScanner(img) + dst := image.NewNRGBA(image.Rect(0, 0, src.w, src.h)) + parallel(0, src.h, func(ys <-chan int) { + for y := range ys { + i := y * dst.Stride + src.scan(0, y, src.w, y+1, dst.Pix[i:i+src.w*4]) + for x := 0; x < src.w; x++ { + r := dst.Pix[i+0] + g := dst.Pix[i+1] + b := dst.Pix[i+2] + f := 0.299*float64(r) + 0.587*float64(g) + 0.114*float64(b) + y := uint8(f + 0.5) + dst.Pix[i+0] = y + dst.Pix[i+1] = y + dst.Pix[i+2] = y + i += 4 + } + } + }) + return dst +} + +// Invert produces an inverted (negated) version of the image. +func Invert(img image.Image) *image.NRGBA { + src := newScanner(img) + dst := image.NewNRGBA(image.Rect(0, 0, src.w, src.h)) + parallel(0, src.h, func(ys <-chan int) { + for y := range ys { + i := y * dst.Stride + src.scan(0, y, src.w, y+1, dst.Pix[i:i+src.w*4]) + for x := 0; x < src.w; x++ { + dst.Pix[i+0] = 255 - dst.Pix[i+0] + dst.Pix[i+1] = 255 - dst.Pix[i+1] + dst.Pix[i+2] = 255 - dst.Pix[i+2] + i += 4 + } + } + }) + return dst +} + +// AdjustContrast changes the contrast of the image using the percentage parameter and returns the adjusted image. +// The percentage must be in range (-100, 100). The percentage = 0 gives the original image. +// The percentage = -100 gives solid gray image. +// +// Examples: +// +// dstImage = imaging.AdjustContrast(srcImage, -10) // decrease image contrast by 10% +// dstImage = imaging.AdjustContrast(srcImage, 20) // increase image contrast by 20% +// +func AdjustContrast(img image.Image, percentage float64) *image.NRGBA { + percentage = math.Min(math.Max(percentage, -100.0), 100.0) + lut := make([]uint8, 256) + + v := (100.0 + percentage) / 100.0 + for i := 0; i < 256; i++ { + if 0 <= v && v <= 1 { + lut[i] = clamp((0.5 + (float64(i)/255.0-0.5)*v) * 255.0) + } else if 1 < v && v < 2 { + lut[i] = clamp((0.5 + (float64(i)/255.0-0.5)*(1/(2.0-v))) * 255.0) + } else { + lut[i] = uint8(float64(i)/255.0+0.5) * 255 + } + } + + return adjustLUT(img, lut) +} + +// AdjustBrightness changes the brightness of the image using the percentage parameter and returns the adjusted image. +// The percentage must be in range (-100, 100). The percentage = 0 gives the original image. +// The percentage = -100 gives solid black image. The percentage = 100 gives solid white image. +// +// Examples: +// +// dstImage = imaging.AdjustBrightness(srcImage, -15) // decrease image brightness by 15% +// dstImage = imaging.AdjustBrightness(srcImage, 10) // increase image brightness by 10% +// +func AdjustBrightness(img image.Image, percentage float64) *image.NRGBA { + percentage = math.Min(math.Max(percentage, -100.0), 100.0) + lut := make([]uint8, 256) + + shift := 255.0 * percentage / 100.0 + for i := 0; i < 256; i++ { + lut[i] = clamp(float64(i) + shift) + } + + return adjustLUT(img, lut) +} + +// AdjustGamma performs a gamma correction on the image and returns the adjusted image. +// Gamma parameter must be positive. Gamma = 1.0 gives the original image. +// Gamma less than 1.0 darkens the image and gamma greater than 1.0 lightens it. +// +// Example: +// +// dstImage = imaging.AdjustGamma(srcImage, 0.7) +// +func AdjustGamma(img image.Image, gamma float64) *image.NRGBA { + e := 1.0 / math.Max(gamma, 0.0001) + lut := make([]uint8, 256) + + for i := 0; i < 256; i++ { + lut[i] = clamp(math.Pow(float64(i)/255.0, e) * 255.0) + } + + return adjustLUT(img, lut) +} + +// AdjustSigmoid changes the contrast of the image using a sigmoidal function and returns the adjusted image. +// It's a non-linear contrast change useful for photo adjustments as it preserves highlight and shadow detail. +// The midpoint parameter is the midpoint of contrast that must be between 0 and 1, typically 0.5. +// The factor parameter indicates how much to increase or decrease the contrast, typically in range (-10, 10). +// If the factor parameter is positive the image contrast is increased otherwise the contrast is decreased. +// +// Examples: +// +// dstImage = imaging.AdjustSigmoid(srcImage, 0.5, 3.0) // increase the contrast +// dstImage = imaging.AdjustSigmoid(srcImage, 0.5, -3.0) // decrease the contrast +// +func AdjustSigmoid(img image.Image, midpoint, factor float64) *image.NRGBA { + if factor == 0 { + return Clone(img) + } + + lut := make([]uint8, 256) + a := math.Min(math.Max(midpoint, 0.0), 1.0) + b := math.Abs(factor) + sig0 := sigmoid(a, b, 0) + sig1 := sigmoid(a, b, 1) + e := 1.0e-6 + + if factor > 0 { + for i := 0; i < 256; i++ { + x := float64(i) / 255.0 + sigX := sigmoid(a, b, x) + f := (sigX - sig0) / (sig1 - sig0) + lut[i] = clamp(f * 255.0) + } + } else { + for i := 0; i < 256; i++ { + x := float64(i) / 255.0 + arg := math.Min(math.Max((sig1-sig0)*x+sig0, e), 1.0-e) + f := a - math.Log(1.0/arg-1.0)/b + lut[i] = clamp(f * 255.0) + } + } + + return adjustLUT(img, lut) +} + +func sigmoid(a, b, x float64) float64 { + return 1 / (1 + math.Exp(b*(a-x))) +} + +// adjustLUT applies the given lookup table to the colors of the image. +func adjustLUT(img image.Image, lut []uint8) *image.NRGBA { + src := newScanner(img) + dst := image.NewNRGBA(image.Rect(0, 0, src.w, src.h)) + parallel(0, src.h, func(ys <-chan int) { + for y := range ys { + i := y * dst.Stride + src.scan(0, y, src.w, y+1, dst.Pix[i:i+src.w*4]) + for x := 0; x < src.w; x++ { + dst.Pix[i+0] = lut[dst.Pix[i+0]] + dst.Pix[i+1] = lut[dst.Pix[i+1]] + dst.Pix[i+2] = lut[dst.Pix[i+2]] + i += 4 + } + } + }) + return dst +} + +// AdjustFunc applies the fn function to each pixel of the img image and returns the adjusted image. +// +// Example: +// +// dstImage = imaging.AdjustFunc( +// srcImage, +// func(c color.NRGBA) color.NRGBA { +// // shift the red channel by 16 +// r := int(c.R) + 16 +// if r > 255 { +// r = 255 +// } +// return color.NRGBA{uint8(r), c.G, c.B, c.A} +// } +// ) +// +func AdjustFunc(img image.Image, fn func(c color.NRGBA) color.NRGBA) *image.NRGBA { + src := newScanner(img) + dst := image.NewNRGBA(image.Rect(0, 0, src.w, src.h)) + parallel(0, src.h, func(ys <-chan int) { + for y := range ys { + i := y * dst.Stride + src.scan(0, y, src.w, y+1, dst.Pix[i:i+src.w*4]) + for x := 0; x < src.w; x++ { + r := dst.Pix[i+0] + g := dst.Pix[i+1] + b := dst.Pix[i+2] + a := dst.Pix[i+3] + c := fn(color.NRGBA{r, g, b, a}) + dst.Pix[i+0] = c.R + dst.Pix[i+1] = c.G + dst.Pix[i+2] = c.B + dst.Pix[i+3] = c.A + i += 4 + } + } + }) + return dst +} diff --git a/vendor/github.com/disintegration/imaging/convolution.go b/vendor/github.com/disintegration/imaging/convolution.go new file mode 100644 index 0000000..9e6404d --- /dev/null +++ b/vendor/github.com/disintegration/imaging/convolution.go @@ -0,0 +1,146 @@ +package imaging + +import ( + "image" +) + +// ConvolveOptions are convolution parameters. +type ConvolveOptions struct { + // If Normalize is true the kernel is normalized before convolution. + Normalize bool + + // If Abs is true the absolute value of each color channel is taken after convolution. + Abs bool + + // Bias is added to each color channel value after convolution. + Bias int +} + +// Convolve3x3 convolves the image with the specified 3x3 convolution kernel. +// Default parameters are used if a nil *ConvolveOptions is passed. +func Convolve3x3(img image.Image, kernel [9]float64, options *ConvolveOptions) *image.NRGBA { + return convolve(img, kernel[:], options) +} + +// Convolve5x5 convolves the image with the specified 5x5 convolution kernel. +// Default parameters are used if a nil *ConvolveOptions is passed. +func Convolve5x5(img image.Image, kernel [25]float64, options *ConvolveOptions) *image.NRGBA { + return convolve(img, kernel[:], options) +} + +func convolve(img image.Image, kernel []float64, options *ConvolveOptions) *image.NRGBA { + src := toNRGBA(img) + w := src.Bounds().Max.X + h := src.Bounds().Max.Y + dst := image.NewNRGBA(image.Rect(0, 0, w, h)) + + if w < 1 || h < 1 { + return dst + } + + if options == nil { + options = &ConvolveOptions{} + } + + if options.Normalize { + normalizeKernel(kernel) + } + + type coef struct { + x, y int + k float64 + } + var coefs []coef + var m int + + switch len(kernel) { + case 9: + m = 1 + case 25: + m = 2 + } + + i := 0 + for y := -m; y <= m; y++ { + for x := -m; x <= m; x++ { + if kernel[i] != 0 { + coefs = append(coefs, coef{x: x, y: y, k: kernel[i]}) + } + i++ + } + } + + parallel(0, h, func(ys <-chan int) { + for y := range ys { + for x := 0; x < w; x++ { + var r, g, b float64 + for _, c := range coefs { + ix := x + c.x + if ix < 0 { + ix = 0 + } else if ix >= w { + ix = w - 1 + } + + iy := y + c.y + if iy < 0 { + iy = 0 + } else if iy >= h { + iy = h - 1 + } + + off := iy*src.Stride + ix*4 + r += float64(src.Pix[off+0]) * c.k + g += float64(src.Pix[off+1]) * c.k + b += float64(src.Pix[off+2]) * c.k + } + + if options.Abs { + if r < 0 { + r = -r + } + if g < 0 { + g = -g + } + if b < 0 { + b = -b + } + } + + if options.Bias != 0 { + r += float64(options.Bias) + g += float64(options.Bias) + b += float64(options.Bias) + } + + srcOff := y*src.Stride + x*4 + dstOff := y*dst.Stride + x*4 + dst.Pix[dstOff+0] = clamp(r) + dst.Pix[dstOff+1] = clamp(g) + dst.Pix[dstOff+2] = clamp(b) + dst.Pix[dstOff+3] = src.Pix[srcOff+3] + } + } + }) + + return dst +} + +func normalizeKernel(kernel []float64) { + var sum, sumpos float64 + for i := range kernel { + sum += kernel[i] + if kernel[i] > 0 { + sumpos += kernel[i] + } + } + if sum != 0 { + for i := range kernel { + kernel[i] /= sum + } + } else if sumpos != 0 { + for i := range kernel { + kernel[i] /= sumpos + } + } +} diff --git a/vendor/github.com/disintegration/imaging/doc.go b/vendor/github.com/disintegration/imaging/doc.go new file mode 100644 index 0000000..5d59b46 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/doc.go @@ -0,0 +1,7 @@ +/* +Package imaging provides basic image processing functions (resize, rotate, crop, brightness/contrast adjustments, etc.). + +All the image processing functions provided by the package accept any image type that implements image.Image interface +as an input, and return a new image of *image.NRGBA type (32bit RGBA colors, not premultiplied by alpha). +*/ +package imaging diff --git a/vendor/github.com/disintegration/imaging/effects.go b/vendor/github.com/disintegration/imaging/effects.go new file mode 100644 index 0000000..b16781f --- /dev/null +++ b/vendor/github.com/disintegration/imaging/effects.go @@ -0,0 +1,165 @@ +package imaging + +import ( + "image" + "math" +) + +func gaussianBlurKernel(x, sigma float64) float64 { + return math.Exp(-(x*x)/(2*sigma*sigma)) / (sigma * math.Sqrt(2*math.Pi)) +} + +// Blur produces a blurred version of the image using a Gaussian function. +// Sigma parameter must be positive and indicates how much the image will be blurred. +// +// Usage example: +// +// dstImage := imaging.Blur(srcImage, 3.5) +// +func Blur(img image.Image, sigma float64) *image.NRGBA { + if sigma <= 0 { + return Clone(img) + } + + radius := int(math.Ceil(sigma * 3.0)) + kernel := make([]float64, radius+1) + + for i := 0; i <= radius; i++ { + kernel[i] = gaussianBlurKernel(float64(i), sigma) + } + + return blurVertical(blurHorizontal(img, kernel), kernel) +} + +func blurHorizontal(img image.Image, kernel []float64) *image.NRGBA { + src := newScanner(img) + dst := image.NewNRGBA(image.Rect(0, 0, src.w, src.h)) + radius := len(kernel) - 1 + + parallel(0, src.h, func(ys <-chan int) { + scanLine := make([]uint8, src.w*4) + for y := range ys { + src.scan(0, y, src.w, y+1, scanLine) + for x := 0; x < src.w; x++ { + min := x - radius + if min < 0 { + min = 0 + } + max := x + radius + if max > src.w-1 { + max = src.w - 1 + } + + var r, g, b, a, wsum float64 + for ix := min; ix <= max; ix++ { + i := ix * 4 + weight := kernel[absint(x-ix)] + wsum += weight + wa := float64(scanLine[i+3]) * weight + r += float64(scanLine[i+0]) * wa + g += float64(scanLine[i+1]) * wa + b += float64(scanLine[i+2]) * wa + a += wa + } + if a != 0 { + r /= a + g /= a + b /= a + } + + j := y*dst.Stride + x*4 + dst.Pix[j+0] = clamp(r) + dst.Pix[j+1] = clamp(g) + dst.Pix[j+2] = clamp(b) + dst.Pix[j+3] = clamp(a / wsum) + } + } + }) + + return dst +} + +func blurVertical(img image.Image, kernel []float64) *image.NRGBA { + src := newScanner(img) + dst := image.NewNRGBA(image.Rect(0, 0, src.w, src.h)) + radius := len(kernel) - 1 + + parallel(0, src.w, func(xs <-chan int) { + scanLine := make([]uint8, src.h*4) + for x := range xs { + src.scan(x, 0, x+1, src.h, scanLine) + for y := 0; y < src.h; y++ { + min := y - radius + if min < 0 { + min = 0 + } + max := y + radius + if max > src.h-1 { + max = src.h - 1 + } + + var r, g, b, a, wsum float64 + for iy := min; iy <= max; iy++ { + i := iy * 4 + weight := kernel[absint(y-iy)] + wsum += weight + wa := float64(scanLine[i+3]) * weight + r += float64(scanLine[i+0]) * wa + g += float64(scanLine[i+1]) * wa + b += float64(scanLine[i+2]) * wa + a += wa + } + if a != 0 { + r /= a + g /= a + b /= a + } + + j := y*dst.Stride + x*4 + dst.Pix[j+0] = clamp(r) + dst.Pix[j+1] = clamp(g) + dst.Pix[j+2] = clamp(b) + dst.Pix[j+3] = clamp(a / wsum) + } + } + }) + + return dst +} + +// Sharpen produces a sharpened version of the image. +// Sigma parameter must be positive and indicates how much the image will be sharpened. +// +// Usage example: +// +// dstImage := imaging.Sharpen(srcImage, 3.5) +// +func Sharpen(img image.Image, sigma float64) *image.NRGBA { + if sigma <= 0 { + return Clone(img) + } + + src := newScanner(img) + dst := image.NewNRGBA(image.Rect(0, 0, src.w, src.h)) + blurred := Blur(img, sigma) + + parallel(0, src.h, func(ys <-chan int) { + scanLine := make([]uint8, src.w*4) + for y := range ys { + src.scan(0, y, src.w, y+1, scanLine) + j := y * dst.Stride + for i := 0; i < src.w*4; i++ { + val := int(scanLine[i])<<1 - int(blurred.Pix[j]) + if val < 0 { + val = 0 + } else if val > 0xff { + val = 0xff + } + dst.Pix[j] = uint8(val) + j++ + } + } + }) + + return dst +} diff --git a/vendor/github.com/disintegration/imaging/helpers.go b/vendor/github.com/disintegration/imaging/helpers.go new file mode 100644 index 0000000..7193e47 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/helpers.go @@ -0,0 +1,280 @@ +package imaging + +import ( + "errors" + "image" + "image/color" + "image/draw" + "image/gif" + "image/jpeg" + "image/png" + "io" + "os" + "path/filepath" + "strings" + + "golang.org/x/image/bmp" + "golang.org/x/image/tiff" +) + +// Format is an image file format. +type Format int + +// Image file formats. +const ( + JPEG Format = iota + PNG + GIF + TIFF + BMP +) + +func (f Format) String() string { + switch f { + case JPEG: + return "JPEG" + case PNG: + return "PNG" + case GIF: + return "GIF" + case TIFF: + return "TIFF" + case BMP: + return "BMP" + default: + return "Unsupported" + } +} + +var ( + // ErrUnsupportedFormat means the given image format (or file extension) is unsupported. + ErrUnsupportedFormat = errors.New("imaging: unsupported image format") +) + +type fileSystem interface { + Create(string) (io.WriteCloser, error) + Open(string) (io.ReadCloser, error) +} + +type localFS struct{} + +func (localFS) Create(name string) (io.WriteCloser, error) { return os.Create(name) } +func (localFS) Open(name string) (io.ReadCloser, error) { return os.Open(name) } + +var fs fileSystem = localFS{} + +// Decode reads an image from r. +func Decode(r io.Reader) (image.Image, error) { + img, _, err := image.Decode(r) + return img, err +} + +// Open loads an image from file +func Open(filename string) (image.Image, error) { + file, err := fs.Open(filename) + if err != nil { + return nil, err + } + defer file.Close() + return Decode(file) +} + +type encodeConfig struct { + jpegQuality int + gifNumColors int + gifQuantizer draw.Quantizer + gifDrawer draw.Drawer + pngCompressionLevel png.CompressionLevel +} + +var defaultEncodeConfig = encodeConfig{ + jpegQuality: 95, + gifNumColors: 256, + gifQuantizer: nil, + gifDrawer: nil, + pngCompressionLevel: png.DefaultCompression, +} + +// EncodeOption sets an optional parameter for the Encode and Save functions. +type EncodeOption func(*encodeConfig) + +// JPEGQuality returns an EncodeOption that sets the output JPEG quality. +// Quality ranges from 1 to 100 inclusive, higher is better. Default is 95. +func JPEGQuality(quality int) EncodeOption { + return func(c *encodeConfig) { + c.jpegQuality = quality + } +} + +// GIFNumColors returns an EncodeOption that sets the maximum number of colors +// used in the GIF-encoded image. It ranges from 1 to 256. Default is 256. +func GIFNumColors(numColors int) EncodeOption { + return func(c *encodeConfig) { + c.gifNumColors = numColors + } +} + +// GIFQuantizer returns an EncodeOption that sets the quantizer that is used to produce +// a palette of the GIF-encoded image. +func GIFQuantizer(quantizer draw.Quantizer) EncodeOption { + return func(c *encodeConfig) { + c.gifQuantizer = quantizer + } +} + +// GIFDrawer returns an EncodeOption that sets the drawer that is used to convert +// the source image to the desired palette of the GIF-encoded image. +func GIFDrawer(drawer draw.Drawer) EncodeOption { + return func(c *encodeConfig) { + c.gifDrawer = drawer + } +} + +// PNGCompressionLevel returns an EncodeOption that sets the compression level +// of the PNG-encoded image. Default is png.DefaultCompression. +func PNGCompressionLevel(level png.CompressionLevel) EncodeOption { + return func(c *encodeConfig) { + c.pngCompressionLevel = level + } +} + +// Encode writes the image img to w in the specified format (JPEG, PNG, GIF, TIFF or BMP). +func Encode(w io.Writer, img image.Image, format Format, opts ...EncodeOption) error { + cfg := defaultEncodeConfig + for _, option := range opts { + option(&cfg) + } + + var err error + switch format { + case JPEG: + var rgba *image.RGBA + if nrgba, ok := img.(*image.NRGBA); ok { + if nrgba.Opaque() { + rgba = &image.RGBA{ + Pix: nrgba.Pix, + Stride: nrgba.Stride, + Rect: nrgba.Rect, + } + } + } + if rgba != nil { + err = jpeg.Encode(w, rgba, &jpeg.Options{Quality: cfg.jpegQuality}) + } else { + err = jpeg.Encode(w, img, &jpeg.Options{Quality: cfg.jpegQuality}) + } + + case PNG: + enc := png.Encoder{CompressionLevel: cfg.pngCompressionLevel} + err = enc.Encode(w, img) + + case GIF: + err = gif.Encode(w, img, &gif.Options{ + NumColors: cfg.gifNumColors, + Quantizer: cfg.gifQuantizer, + Drawer: cfg.gifDrawer, + }) + + case TIFF: + err = tiff.Encode(w, img, &tiff.Options{Compression: tiff.Deflate, Predictor: true}) + + case BMP: + err = bmp.Encode(w, img) + + default: + err = ErrUnsupportedFormat + } + return err +} + +// Save saves the image to file with the specified filename. +// The format is determined from the filename extension: "jpg" (or "jpeg"), "png", "gif", "tif" (or "tiff") and "bmp" are supported. +// +// Examples: +// +// // Save the image as PNG. +// err := imaging.Save(img, "out.png") +// +// // Save the image as JPEG with optional quality parameter set to 80. +// err := imaging.Save(img, "out.jpg", imaging.JPEGQuality(80)) +// +func Save(img image.Image, filename string, opts ...EncodeOption) (err error) { + formats := map[string]Format{ + ".jpg": JPEG, + ".jpeg": JPEG, + ".png": PNG, + ".tif": TIFF, + ".tiff": TIFF, + ".bmp": BMP, + ".gif": GIF, + } + + ext := strings.ToLower(filepath.Ext(filename)) + f, ok := formats[ext] + if !ok { + return ErrUnsupportedFormat + } + + file, err := fs.Create(filename) + if err != nil { + return err + } + + defer func() { + cerr := file.Close() + if err == nil { + err = cerr + } + }() + + return Encode(file, img, f, opts...) +} + +// New creates a new image with the specified width and height, and fills it with the specified color. +func New(width, height int, fillColor color.Color) *image.NRGBA { + if width <= 0 || height <= 0 { + return &image.NRGBA{} + } + + dst := image.NewNRGBA(image.Rect(0, 0, width, height)) + c := color.NRGBAModel.Convert(fillColor).(color.NRGBA) + + if c.R == 0 && c.G == 0 && c.B == 0 && c.A == 0 { + return dst + } + + // Fill the first row. + i := 0 + for x := 0; x < width; x++ { + dst.Pix[i+0] = c.R + dst.Pix[i+1] = c.G + dst.Pix[i+2] = c.B + dst.Pix[i+3] = c.A + i += 4 + } + + // Copy the first row to other rows. + size := width * 4 + parallel(1, height, func(ys <-chan int) { + for y := range ys { + i = y * dst.Stride + copy(dst.Pix[i:i+size], dst.Pix[0:size]) + } + }) + + return dst +} + +// Clone returns a copy of the given image. +func Clone(img image.Image) *image.NRGBA { + src := newScanner(img) + dst := image.NewNRGBA(image.Rect(0, 0, src.w, src.h)) + size := src.w * 4 + parallel(0, src.h, func(ys <-chan int) { + for y := range ys { + i := y * dst.Stride + src.scan(0, y, src.w, y+1, dst.Pix[i:i+size]) + } + }) + return dst +} diff --git a/vendor/github.com/disintegration/imaging/histogram.go b/vendor/github.com/disintegration/imaging/histogram.go new file mode 100644 index 0000000..5bcb001 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/histogram.go @@ -0,0 +1,51 @@ +package imaging + +import ( + "image" + "sync" +) + +// Histogram returns a normalized histogram of an image. +// +// Resulting histogram is represented as an array of 256 floats, where +// histogram[i] is a probability of a pixel being of a particular luminance i. +func Histogram(img image.Image) [256]float64 { + var mu sync.Mutex + var histogram [256]float64 + var total float64 + + src := newScanner(img) + if src.w == 0 || src.h == 0 { + return histogram + } + + parallel(0, src.h, func(ys <-chan int) { + var tmpHistogram [256]float64 + var tmpTotal float64 + scanLine := make([]uint8, src.w*4) + for y := range ys { + src.scan(0, y, src.w, y+1, scanLine) + i := 0 + for x := 0; x < src.w; x++ { + r := scanLine[i+0] + g := scanLine[i+1] + b := scanLine[i+2] + y := 0.299*float32(r) + 0.587*float32(g) + 0.114*float32(b) + tmpHistogram[int(y+0.5)]++ + tmpTotal++ + i += 4 + } + } + mu.Lock() + for i := 0; i < 256; i++ { + histogram[i] += tmpHistogram[i] + } + total += tmpTotal + mu.Unlock() + }) + + for i := 0; i < 256; i++ { + histogram[i] = histogram[i] / total + } + return histogram +} diff --git a/vendor/github.com/disintegration/imaging/resize.go b/vendor/github.com/disintegration/imaging/resize.go new file mode 100644 index 0000000..97f498a --- /dev/null +++ b/vendor/github.com/disintegration/imaging/resize.go @@ -0,0 +1,572 @@ +package imaging + +import ( + "image" + "math" +) + +type indexWeight struct { + index int + weight float64 +} + +func precomputeWeights(dstSize, srcSize int, filter ResampleFilter) [][]indexWeight { + du := float64(srcSize) / float64(dstSize) + scale := du + if scale < 1.0 { + scale = 1.0 + } + ru := math.Ceil(scale * filter.Support) + + out := make([][]indexWeight, dstSize) + tmp := make([]indexWeight, 0, dstSize*int(ru+2)*2) + + for v := 0; v < dstSize; v++ { + fu := (float64(v)+0.5)*du - 0.5 + + begin := int(math.Ceil(fu - ru)) + if begin < 0 { + begin = 0 + } + end := int(math.Floor(fu + ru)) + if end > srcSize-1 { + end = srcSize - 1 + } + + var sum float64 + for u := begin; u <= end; u++ { + w := filter.Kernel((float64(u) - fu) / scale) + if w != 0 { + sum += w + tmp = append(tmp, indexWeight{index: u, weight: w}) + } + } + if sum != 0 { + for i := range tmp { + tmp[i].weight /= sum + } + } + + out[v] = tmp + tmp = tmp[len(tmp):] + } + + return out +} + +// Resize resizes the image to the specified width and height using the specified resampling +// filter and returns the transformed image. If one of width or height is 0, the image aspect +// ratio is preserved. +// +// Supported resample filters: NearestNeighbor, Box, Linear, Hermite, MitchellNetravali, +// CatmullRom, BSpline, Gaussian, Lanczos, Hann, Hamming, Blackman, Bartlett, Welch, Cosine. +// +// Usage example: +// +// dstImage := imaging.Resize(srcImage, 800, 600, imaging.Lanczos) +// +func Resize(img image.Image, width, height int, filter ResampleFilter) *image.NRGBA { + dstW, dstH := width, height + if dstW < 0 || dstH < 0 { + return &image.NRGBA{} + } + if dstW == 0 && dstH == 0 { + return &image.NRGBA{} + } + + srcW := img.Bounds().Dx() + srcH := img.Bounds().Dy() + if srcW <= 0 || srcH <= 0 { + return &image.NRGBA{} + } + + // If new width or height is 0 then preserve aspect ratio, minimum 1px. + if dstW == 0 { + tmpW := float64(dstH) * float64(srcW) / float64(srcH) + dstW = int(math.Max(1.0, math.Floor(tmpW+0.5))) + } + if dstH == 0 { + tmpH := float64(dstW) * float64(srcH) / float64(srcW) + dstH = int(math.Max(1.0, math.Floor(tmpH+0.5))) + } + + if filter.Support <= 0 { + // Nearest-neighbor special case. + return resizeNearest(img, dstW, dstH) + } + + if srcW != dstW && srcH != dstH { + return resizeVertical(resizeHorizontal(img, dstW, filter), dstH, filter) + } + if srcW != dstW { + return resizeHorizontal(img, dstW, filter) + } + if srcH != dstH { + return resizeVertical(img, dstH, filter) + } + return Clone(img) +} + +func resizeHorizontal(img image.Image, width int, filter ResampleFilter) *image.NRGBA { + src := newScanner(img) + dst := image.NewNRGBA(image.Rect(0, 0, width, src.h)) + weights := precomputeWeights(width, src.w, filter) + parallel(0, src.h, func(ys <-chan int) { + scanLine := make([]uint8, src.w*4) + for y := range ys { + src.scan(0, y, src.w, y+1, scanLine) + j0 := y * dst.Stride + for x := 0; x < width; x++ { + var r, g, b, a float64 + for _, w := range weights[x] { + i := w.index * 4 + aw := float64(scanLine[i+3]) * w.weight + r += float64(scanLine[i+0]) * aw + g += float64(scanLine[i+1]) * aw + b += float64(scanLine[i+2]) * aw + a += aw + } + if a != 0 { + aInv := 1 / a + j := j0 + x*4 + dst.Pix[j+0] = clamp(r * aInv) + dst.Pix[j+1] = clamp(g * aInv) + dst.Pix[j+2] = clamp(b * aInv) + dst.Pix[j+3] = clamp(a) + } + } + } + }) + return dst +} + +func resizeVertical(img image.Image, height int, filter ResampleFilter) *image.NRGBA { + src := newScanner(img) + dst := image.NewNRGBA(image.Rect(0, 0, src.w, height)) + weights := precomputeWeights(height, src.h, filter) + parallel(0, src.w, func(xs <-chan int) { + scanLine := make([]uint8, src.h*4) + for x := range xs { + src.scan(x, 0, x+1, src.h, scanLine) + for y := 0; y < height; y++ { + var r, g, b, a float64 + for _, w := range weights[y] { + i := w.index * 4 + aw := float64(scanLine[i+3]) * w.weight + r += float64(scanLine[i+0]) * aw + g += float64(scanLine[i+1]) * aw + b += float64(scanLine[i+2]) * aw + a += aw + } + if a != 0 { + aInv := 1 / a + j := y*dst.Stride + x*4 + dst.Pix[j+0] = clamp(r * aInv) + dst.Pix[j+1] = clamp(g * aInv) + dst.Pix[j+2] = clamp(b * aInv) + dst.Pix[j+3] = clamp(a) + } + } + } + }) + return dst +} + +// resizeNearest is a fast nearest-neighbor resize, no filtering. +func resizeNearest(img image.Image, width, height int) *image.NRGBA { + dst := image.NewNRGBA(image.Rect(0, 0, width, height)) + dx := float64(img.Bounds().Dx()) / float64(width) + dy := float64(img.Bounds().Dy()) / float64(height) + + if dx > 1 && dy > 1 { + src := newScanner(img) + parallel(0, height, func(ys <-chan int) { + for y := range ys { + srcY := int((float64(y) + 0.5) * dy) + dstOff := y * dst.Stride + for x := 0; x < width; x++ { + srcX := int((float64(x) + 0.5) * dx) + src.scan(srcX, srcY, srcX+1, srcY+1, dst.Pix[dstOff:dstOff+4]) + dstOff += 4 + } + } + }) + } else { + src := toNRGBA(img) + parallel(0, height, func(ys <-chan int) { + for y := range ys { + srcY := int((float64(y) + 0.5) * dy) + srcOff0 := srcY * src.Stride + dstOff := y * dst.Stride + for x := 0; x < width; x++ { + srcX := int((float64(x) + 0.5) * dx) + srcOff := srcOff0 + srcX*4 + copy(dst.Pix[dstOff:dstOff+4], src.Pix[srcOff:srcOff+4]) + dstOff += 4 + } + } + }) + } + + return dst +} + +// Fit scales down the image using the specified resample filter to fit the specified +// maximum width and height and returns the transformed image. +// +// Supported resample filters: NearestNeighbor, Box, Linear, Hermite, MitchellNetravali, +// CatmullRom, BSpline, Gaussian, Lanczos, Hann, Hamming, Blackman, Bartlett, Welch, Cosine. +// +// Usage example: +// +// dstImage := imaging.Fit(srcImage, 800, 600, imaging.Lanczos) +// +func Fit(img image.Image, width, height int, filter ResampleFilter) *image.NRGBA { + maxW, maxH := width, height + + if maxW <= 0 || maxH <= 0 { + return &image.NRGBA{} + } + + srcBounds := img.Bounds() + srcW := srcBounds.Dx() + srcH := srcBounds.Dy() + + if srcW <= 0 || srcH <= 0 { + return &image.NRGBA{} + } + + if srcW <= maxW && srcH <= maxH { + return Clone(img) + } + + srcAspectRatio := float64(srcW) / float64(srcH) + maxAspectRatio := float64(maxW) / float64(maxH) + + var newW, newH int + if srcAspectRatio > maxAspectRatio { + newW = maxW + newH = int(float64(newW) / srcAspectRatio) + } else { + newH = maxH + newW = int(float64(newH) * srcAspectRatio) + } + + return Resize(img, newW, newH, filter) +} + +// Fill scales the image to the smallest possible size that will cover the specified dimensions, +// crops the resized image to the specified dimensions using the given anchor point and returns +// the transformed image. +// +// Supported resample filters: NearestNeighbor, Box, Linear, Hermite, MitchellNetravali, +// CatmullRom, BSpline, Gaussian, Lanczos, Hann, Hamming, Blackman, Bartlett, Welch, Cosine. +// +// Usage example: +// +// dstImage := imaging.Fill(srcImage, 800, 600, imaging.Center, imaging.Lanczos) +// +func Fill(img image.Image, width, height int, anchor Anchor, filter ResampleFilter) *image.NRGBA { + minW, minH := width, height + + if minW <= 0 || minH <= 0 { + return &image.NRGBA{} + } + + srcBounds := img.Bounds() + srcW := srcBounds.Dx() + srcH := srcBounds.Dy() + + if srcW <= 0 || srcH <= 0 { + return &image.NRGBA{} + } + + if srcW == minW && srcH == minH { + return Clone(img) + } + + srcAspectRatio := float64(srcW) / float64(srcH) + minAspectRatio := float64(minW) / float64(minH) + + var tmp *image.NRGBA + if srcAspectRatio < minAspectRatio { + tmp = Resize(img, minW, 0, filter) + } else { + tmp = Resize(img, 0, minH, filter) + } + + return CropAnchor(tmp, minW, minH, anchor) +} + +// Thumbnail scales the image up or down using the specified resample filter, crops it +// to the specified width and hight and returns the transformed image. +// +// Supported resample filters: NearestNeighbor, Box, Linear, Hermite, MitchellNetravali, +// CatmullRom, BSpline, Gaussian, Lanczos, Hann, Hamming, Blackman, Bartlett, Welch, Cosine. +// +// Usage example: +// +// dstImage := imaging.Thumbnail(srcImage, 100, 100, imaging.Lanczos) +// +func Thumbnail(img image.Image, width, height int, filter ResampleFilter) *image.NRGBA { + return Fill(img, width, height, Center, filter) +} + +// ResampleFilter is a resampling filter struct. It can be used to define custom filters. +// +// Supported resample filters: NearestNeighbor, Box, Linear, Hermite, MitchellNetravali, +// CatmullRom, BSpline, Gaussian, Lanczos, Hann, Hamming, Blackman, Bartlett, Welch, Cosine. +// +// General filter recommendations: +// +// - Lanczos +// High-quality resampling filter for photographic images yielding sharp results. +// It's slower than cubic filters (see below). +// +// - CatmullRom +// A sharp cubic filter. It's a good filter for both upscaling and downscaling if sharp results are needed. +// +// - MitchellNetravali +// A high quality cubic filter that produces smoother results with less ringing artifacts than CatmullRom. +// +// - BSpline +// A good filter if a very smooth output is needed. +// +// - Linear +// Bilinear interpolation filter, produces reasonably good, smooth output. +// It's faster than cubic filters. +// +// - Box +// Simple and fast averaging filter appropriate for downscaling. +// When upscaling it's similar to NearestNeighbor. +// +// - NearestNeighbor +// Fastest resampling filter, no antialiasing. +// +type ResampleFilter struct { + Support float64 + Kernel func(float64) float64 +} + +// NearestNeighbor is a nearest-neighbor filter (no anti-aliasing). +var NearestNeighbor ResampleFilter + +// Box filter (averaging pixels). +var Box ResampleFilter + +// Linear filter. +var Linear ResampleFilter + +// Hermite cubic spline filter (BC-spline; B=0; C=0). +var Hermite ResampleFilter + +// MitchellNetravali is Mitchell-Netravali cubic filter (BC-spline; B=1/3; C=1/3). +var MitchellNetravali ResampleFilter + +// CatmullRom is a Catmull-Rom - sharp cubic filter (BC-spline; B=0; C=0.5). +var CatmullRom ResampleFilter + +// BSpline is a smooth cubic filter (BC-spline; B=1; C=0). +var BSpline ResampleFilter + +// Gaussian is a Gaussian blurring Filter. +var Gaussian ResampleFilter + +// Bartlett is a Bartlett-windowed sinc filter (3 lobes). +var Bartlett ResampleFilter + +// Lanczos filter (3 lobes). +var Lanczos ResampleFilter + +// Hann is a Hann-windowed sinc filter (3 lobes). +var Hann ResampleFilter + +// Hamming is a Hamming-windowed sinc filter (3 lobes). +var Hamming ResampleFilter + +// Blackman is a Blackman-windowed sinc filter (3 lobes). +var Blackman ResampleFilter + +// Welch is a Welch-windowed sinc filter (parabolic window, 3 lobes). +var Welch ResampleFilter + +// Cosine is a Cosine-windowed sinc filter (3 lobes). +var Cosine ResampleFilter + +func bcspline(x, b, c float64) float64 { + var y float64 + x = math.Abs(x) + if x < 1.0 { + y = ((12-9*b-6*c)*x*x*x + (-18+12*b+6*c)*x*x + (6 - 2*b)) / 6 + } else if x < 2.0 { + y = ((-b-6*c)*x*x*x + (6*b+30*c)*x*x + (-12*b-48*c)*x + (8*b + 24*c)) / 6 + } + return y +} + +func sinc(x float64) float64 { + if x == 0 { + return 1 + } + return math.Sin(math.Pi*x) / (math.Pi * x) +} + +func init() { + NearestNeighbor = ResampleFilter{ + Support: 0.0, // special case - not applying the filter + } + + Box = ResampleFilter{ + Support: 0.5, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x <= 0.5 { + return 1.0 + } + return 0 + }, + } + + Linear = ResampleFilter{ + Support: 1.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 1.0 { + return 1.0 - x + } + return 0 + }, + } + + Hermite = ResampleFilter{ + Support: 1.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 1.0 { + return bcspline(x, 0.0, 0.0) + } + return 0 + }, + } + + MitchellNetravali = ResampleFilter{ + Support: 2.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 2.0 { + return bcspline(x, 1.0/3.0, 1.0/3.0) + } + return 0 + }, + } + + CatmullRom = ResampleFilter{ + Support: 2.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 2.0 { + return bcspline(x, 0.0, 0.5) + } + return 0 + }, + } + + BSpline = ResampleFilter{ + Support: 2.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 2.0 { + return bcspline(x, 1.0, 0.0) + } + return 0 + }, + } + + Gaussian = ResampleFilter{ + Support: 2.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 2.0 { + return math.Exp(-2 * x * x) + } + return 0 + }, + } + + Bartlett = ResampleFilter{ + Support: 3.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 3.0 { + return sinc(x) * (3.0 - x) / 3.0 + } + return 0 + }, + } + + Lanczos = ResampleFilter{ + Support: 3.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 3.0 { + return sinc(x) * sinc(x/3.0) + } + return 0 + }, + } + + Hann = ResampleFilter{ + Support: 3.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 3.0 { + return sinc(x) * (0.5 + 0.5*math.Cos(math.Pi*x/3.0)) + } + return 0 + }, + } + + Hamming = ResampleFilter{ + Support: 3.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 3.0 { + return sinc(x) * (0.54 + 0.46*math.Cos(math.Pi*x/3.0)) + } + return 0 + }, + } + + Blackman = ResampleFilter{ + Support: 3.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 3.0 { + return sinc(x) * (0.42 - 0.5*math.Cos(math.Pi*x/3.0+math.Pi) + 0.08*math.Cos(2.0*math.Pi*x/3.0)) + } + return 0 + }, + } + + Welch = ResampleFilter{ + Support: 3.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 3.0 { + return sinc(x) * (1.0 - (x * x / 9.0)) + } + return 0 + }, + } + + Cosine = ResampleFilter{ + Support: 3.0, + Kernel: func(x float64) float64 { + x = math.Abs(x) + if x < 3.0 { + return sinc(x) * math.Cos((math.Pi/2.0)*(x/3.0)) + } + return 0 + }, + } +} diff --git a/vendor/github.com/disintegration/imaging/scanner.go b/vendor/github.com/disintegration/imaging/scanner.go new file mode 100644 index 0000000..c4dbfe1 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/scanner.go @@ -0,0 +1,250 @@ +package imaging + +import ( + "image" + "image/color" +) + +type scanner struct { + image image.Image + w, h int + palette []color.NRGBA +} + +func newScanner(img image.Image) *scanner { + s := &scanner{ + image: img, + w: img.Bounds().Dx(), + h: img.Bounds().Dy(), + } + if img, ok := img.(*image.Paletted); ok { + s.palette = make([]color.NRGBA, len(img.Palette)) + for i := 0; i < len(img.Palette); i++ { + s.palette[i] = color.NRGBAModel.Convert(img.Palette[i]).(color.NRGBA) + } + } + return s +} + +// scan scans the given rectangular region of the image into dst. +func (s *scanner) scan(x1, y1, x2, y2 int, dst []uint8) { + switch img := s.image.(type) { + case *image.NRGBA: + size := (x2 - x1) * 4 + j := 0 + i := y1*img.Stride + x1*4 + for y := y1; y < y2; y++ { + copy(dst[j:j+size], img.Pix[i:i+size]) + j += size + i += img.Stride + } + + case *image.NRGBA64: + j := 0 + for y := y1; y < y2; y++ { + i := y*img.Stride + x1*8 + for x := x1; x < x2; x++ { + dst[j+0] = img.Pix[i+0] + dst[j+1] = img.Pix[i+2] + dst[j+2] = img.Pix[i+4] + dst[j+3] = img.Pix[i+6] + j += 4 + i += 8 + } + } + + case *image.RGBA: + j := 0 + for y := y1; y < y2; y++ { + i := y*img.Stride + x1*4 + for x := x1; x < x2; x++ { + a := img.Pix[i+3] + switch a { + case 0: + dst[j+0] = 0 + dst[j+1] = 0 + dst[j+2] = 0 + case 0xff: + dst[j+0] = img.Pix[i+0] + dst[j+1] = img.Pix[i+1] + dst[j+2] = img.Pix[i+2] + default: + r16 := uint16(img.Pix[i+0]) + g16 := uint16(img.Pix[i+1]) + b16 := uint16(img.Pix[i+2]) + a16 := uint16(a) + dst[j+0] = uint8(r16 * 0xff / a16) + dst[j+1] = uint8(g16 * 0xff / a16) + dst[j+2] = uint8(b16 * 0xff / a16) + } + dst[j+3] = a + j += 4 + i += 4 + } + } + + case *image.RGBA64: + j := 0 + for y := y1; y < y2; y++ { + i := y*img.Stride + x1*8 + for x := x1; x < x2; x++ { + a := img.Pix[i+6] + switch a { + case 0: + dst[j+0] = 0 + dst[j+1] = 0 + dst[j+2] = 0 + case 0xff: + dst[j+0] = img.Pix[i+0] + dst[j+1] = img.Pix[i+2] + dst[j+2] = img.Pix[i+4] + default: + r32 := uint32(img.Pix[i+0])<<8 | uint32(img.Pix[i+1]) + g32 := uint32(img.Pix[i+2])<<8 | uint32(img.Pix[i+3]) + b32 := uint32(img.Pix[i+4])<<8 | uint32(img.Pix[i+5]) + a32 := uint32(img.Pix[i+6])<<8 | uint32(img.Pix[i+7]) + dst[j+0] = uint8((r32 * 0xffff / a32) >> 8) + dst[j+1] = uint8((g32 * 0xffff / a32) >> 8) + dst[j+2] = uint8((b32 * 0xffff / a32) >> 8) + } + dst[j+3] = a + j += 4 + i += 8 + } + } + + case *image.Gray: + j := 0 + for y := y1; y < y2; y++ { + i := y*img.Stride + x1 + for x := x1; x < x2; x++ { + c := img.Pix[i] + dst[j+0] = c + dst[j+1] = c + dst[j+2] = c + dst[j+3] = 0xff + j += 4 + i++ + } + } + + case *image.Gray16: + j := 0 + for y := y1; y < y2; y++ { + i := y*img.Stride + x1*2 + for x := x1; x < x2; x++ { + c := img.Pix[i] + dst[j+0] = c + dst[j+1] = c + dst[j+2] = c + dst[j+3] = 0xff + j += 4 + i += 2 + } + } + + case *image.YCbCr: + j := 0 + x1 += img.Rect.Min.X + x2 += img.Rect.Min.X + y1 += img.Rect.Min.Y + y2 += img.Rect.Min.Y + for y := y1; y < y2; y++ { + iy := (y-img.Rect.Min.Y)*img.YStride + (x1 - img.Rect.Min.X) + for x := x1; x < x2; x++ { + var ic int + switch img.SubsampleRatio { + case image.YCbCrSubsampleRatio444: + ic = (y-img.Rect.Min.Y)*img.CStride + (x - img.Rect.Min.X) + case image.YCbCrSubsampleRatio422: + ic = (y-img.Rect.Min.Y)*img.CStride + (x/2 - img.Rect.Min.X/2) + case image.YCbCrSubsampleRatio420: + ic = (y/2-img.Rect.Min.Y/2)*img.CStride + (x/2 - img.Rect.Min.X/2) + case image.YCbCrSubsampleRatio440: + ic = (y/2-img.Rect.Min.Y/2)*img.CStride + (x - img.Rect.Min.X) + default: + ic = img.COffset(x, y) + } + + yy := int(img.Y[iy]) + cb := int(img.Cb[ic]) - 128 + cr := int(img.Cr[ic]) - 128 + + r := (yy<<16 + 91881*cr + 1<<15) >> 16 + if r > 0xff { + r = 0xff + } else if r < 0 { + r = 0 + } + + g := (yy<<16 - 22554*cb - 46802*cr + 1<<15) >> 16 + if g > 0xff { + g = 0xff + } else if g < 0 { + g = 0 + } + + b := (yy<<16 + 116130*cb + 1<<15) >> 16 + if b > 0xff { + b = 0xff + } else if b < 0 { + b = 0 + } + + dst[j+0] = uint8(r) + dst[j+1] = uint8(g) + dst[j+2] = uint8(b) + dst[j+3] = 0xff + + iy++ + j += 4 + } + } + + case *image.Paletted: + j := 0 + for y := y1; y < y2; y++ { + i := y*img.Stride + x1 + for x := x1; x < x2; x++ { + c := s.palette[img.Pix[i]] + dst[j+0] = c.R + dst[j+1] = c.G + dst[j+2] = c.B + dst[j+3] = c.A + j += 4 + i++ + } + } + + default: + j := 0 + b := s.image.Bounds() + x1 += b.Min.X + x2 += b.Min.X + y1 += b.Min.Y + y2 += b.Min.Y + for y := y1; y < y2; y++ { + for x := x1; x < x2; x++ { + r16, g16, b16, a16 := s.image.At(x, y).RGBA() + switch a16 { + case 0xffff: + dst[j+0] = uint8(r16 >> 8) + dst[j+1] = uint8(g16 >> 8) + dst[j+2] = uint8(b16 >> 8) + dst[j+3] = 0xff + case 0: + dst[j+0] = 0 + dst[j+1] = 0 + dst[j+2] = 0 + dst[j+3] = 0 + default: + dst[j+0] = uint8(((r16 * 0xffff) / a16) >> 8) + dst[j+1] = uint8(((g16 * 0xffff) / a16) >> 8) + dst[j+2] = uint8(((b16 * 0xffff) / a16) >> 8) + dst[j+3] = uint8(a16 >> 8) + } + j += 4 + } + } + } +} diff --git a/vendor/github.com/disintegration/imaging/tools.go b/vendor/github.com/disintegration/imaging/tools.go new file mode 100644 index 0000000..fae1fa1 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/tools.go @@ -0,0 +1,213 @@ +package imaging + +import ( + "image" + "math" +) + +// Anchor is the anchor point for image alignment. +type Anchor int + +// Anchor point positions. +const ( + Center Anchor = iota + TopLeft + Top + TopRight + Left + Right + BottomLeft + Bottom + BottomRight +) + +func anchorPt(b image.Rectangle, w, h int, anchor Anchor) image.Point { + var x, y int + switch anchor { + case TopLeft: + x = b.Min.X + y = b.Min.Y + case Top: + x = b.Min.X + (b.Dx()-w)/2 + y = b.Min.Y + case TopRight: + x = b.Max.X - w + y = b.Min.Y + case Left: + x = b.Min.X + y = b.Min.Y + (b.Dy()-h)/2 + case Right: + x = b.Max.X - w + y = b.Min.Y + (b.Dy()-h)/2 + case BottomLeft: + x = b.Min.X + y = b.Max.Y - h + case Bottom: + x = b.Min.X + (b.Dx()-w)/2 + y = b.Max.Y - h + case BottomRight: + x = b.Max.X - w + y = b.Max.Y - h + default: + x = b.Min.X + (b.Dx()-w)/2 + y = b.Min.Y + (b.Dy()-h)/2 + } + return image.Pt(x, y) +} + +// Crop cuts out a rectangular region with the specified bounds +// from the image and returns the cropped image. +func Crop(img image.Image, rect image.Rectangle) *image.NRGBA { + r := rect.Intersect(img.Bounds()).Sub(img.Bounds().Min) + if r.Empty() { + return &image.NRGBA{} + } + src := newScanner(img) + dst := image.NewNRGBA(image.Rect(0, 0, r.Dx(), r.Dy())) + rowSize := r.Dx() * 4 + parallel(r.Min.Y, r.Max.Y, func(ys <-chan int) { + for y := range ys { + i := (y - r.Min.Y) * dst.Stride + src.scan(r.Min.X, y, r.Max.X, y+1, dst.Pix[i:i+rowSize]) + } + }) + return dst +} + +// CropAnchor cuts out a rectangular region with the specified size +// from the image using the specified anchor point and returns the cropped image. +func CropAnchor(img image.Image, width, height int, anchor Anchor) *image.NRGBA { + srcBounds := img.Bounds() + pt := anchorPt(srcBounds, width, height, anchor) + r := image.Rect(0, 0, width, height).Add(pt) + b := srcBounds.Intersect(r) + return Crop(img, b) +} + +// CropCenter cuts out a rectangular region with the specified size +// from the center of the image and returns the cropped image. +func CropCenter(img image.Image, width, height int) *image.NRGBA { + return CropAnchor(img, width, height, Center) +} + +// Paste pastes the img image to the background image at the specified position and returns the combined image. +func Paste(background, img image.Image, pos image.Point) *image.NRGBA { + dst := Clone(background) + pos = pos.Sub(background.Bounds().Min) + pasteRect := image.Rectangle{Min: pos, Max: pos.Add(img.Bounds().Size())} + interRect := pasteRect.Intersect(dst.Bounds()) + if interRect.Empty() { + return dst + } + src := newScanner(img) + parallel(interRect.Min.Y, interRect.Max.Y, func(ys <-chan int) { + for y := range ys { + x1 := interRect.Min.X - pasteRect.Min.X + x2 := interRect.Max.X - pasteRect.Min.X + y1 := y - pasteRect.Min.Y + y2 := y1 + 1 + i1 := y*dst.Stride + interRect.Min.X*4 + i2 := i1 + interRect.Dx()*4 + src.scan(x1, y1, x2, y2, dst.Pix[i1:i2]) + } + }) + return dst +} + +// PasteCenter pastes the img image to the center of the background image and returns the combined image. +func PasteCenter(background, img image.Image) *image.NRGBA { + bgBounds := background.Bounds() + bgW := bgBounds.Dx() + bgH := bgBounds.Dy() + bgMinX := bgBounds.Min.X + bgMinY := bgBounds.Min.Y + + centerX := bgMinX + bgW/2 + centerY := bgMinY + bgH/2 + + x0 := centerX - img.Bounds().Dx()/2 + y0 := centerY - img.Bounds().Dy()/2 + + return Paste(background, img, image.Pt(x0, y0)) +} + +// Overlay draws the img image over the background image at given position +// and returns the combined image. Opacity parameter is the opacity of the img +// image layer, used to compose the images, it must be from 0.0 to 1.0. +// +// Usage examples: +// +// // Draw spriteImage over backgroundImage at the given position (x=50, y=50). +// dstImage := imaging.Overlay(backgroundImage, spriteImage, image.Pt(50, 50), 1.0) +// +// // Blend two opaque images of the same size. +// dstImage := imaging.Overlay(imageOne, imageTwo, image.Pt(0, 0), 0.5) +// +func Overlay(background, img image.Image, pos image.Point, opacity float64) *image.NRGBA { + opacity = math.Min(math.Max(opacity, 0.0), 1.0) // Ensure 0.0 <= opacity <= 1.0. + dst := Clone(background) + pos = pos.Sub(background.Bounds().Min) + pasteRect := image.Rectangle{Min: pos, Max: pos.Add(img.Bounds().Size())} + interRect := pasteRect.Intersect(dst.Bounds()) + if interRect.Empty() { + return dst + } + src := newScanner(img) + parallel(interRect.Min.Y, interRect.Max.Y, func(ys <-chan int) { + scanLine := make([]uint8, interRect.Dx()*4) + for y := range ys { + x1 := interRect.Min.X - pasteRect.Min.X + x2 := interRect.Max.X - pasteRect.Min.X + y1 := y - pasteRect.Min.Y + y2 := y1 + 1 + src.scan(x1, y1, x2, y2, scanLine) + i := y*dst.Stride + interRect.Min.X*4 + j := 0 + for x := interRect.Min.X; x < interRect.Max.X; x++ { + r1 := float64(dst.Pix[i+0]) + g1 := float64(dst.Pix[i+1]) + b1 := float64(dst.Pix[i+2]) + a1 := float64(dst.Pix[i+3]) + + r2 := float64(scanLine[j+0]) + g2 := float64(scanLine[j+1]) + b2 := float64(scanLine[j+2]) + a2 := float64(scanLine[j+3]) + + coef2 := opacity * a2 / 255 + coef1 := (1 - coef2) * a1 / 255 + coefSum := coef1 + coef2 + coef1 /= coefSum + coef2 /= coefSum + + dst.Pix[i+0] = uint8(r1*coef1 + r2*coef2) + dst.Pix[i+1] = uint8(g1*coef1 + g2*coef2) + dst.Pix[i+2] = uint8(b1*coef1 + b2*coef2) + dst.Pix[i+3] = uint8(math.Min(a1+a2*opacity*(255-a1)/255, 255)) + + i += 4 + j += 4 + } + } + }) + return dst +} + +// OverlayCenter overlays the img image to the center of the background image and +// returns the combined image. Opacity parameter is the opacity of the img +// image layer, used to compose the images, it must be from 0.0 to 1.0. +func OverlayCenter(background, img image.Image, opacity float64) *image.NRGBA { + bgBounds := background.Bounds() + bgW := bgBounds.Dx() + bgH := bgBounds.Dy() + bgMinX := bgBounds.Min.X + bgMinY := bgBounds.Min.Y + + centerX := bgMinX + bgW/2 + centerY := bgMinY + bgH/2 + + x0 := centerX - img.Bounds().Dx()/2 + y0 := centerY - img.Bounds().Dy()/2 + + return Overlay(background, img, image.Point{x0, y0}, opacity) +} diff --git a/vendor/github.com/disintegration/imaging/transform.go b/vendor/github.com/disintegration/imaging/transform.go new file mode 100644 index 0000000..d788d0d --- /dev/null +++ b/vendor/github.com/disintegration/imaging/transform.go @@ -0,0 +1,271 @@ +package imaging + +import ( + "image" + "image/color" + "math" +) + +// FlipH flips the image horizontally (from left to right) and returns the transformed image. +func FlipH(img image.Image) *image.NRGBA { + src := newScanner(img) + dstW := src.w + dstH := src.h + rowSize := dstW * 4 + dst := image.NewNRGBA(image.Rect(0, 0, dstW, dstH)) + parallel(0, dstH, func(ys <-chan int) { + for dstY := range ys { + i := dstY * dst.Stride + srcY := dstY + src.scan(0, srcY, src.w, srcY+1, dst.Pix[i:i+rowSize]) + reverse(dst.Pix[i : i+rowSize]) + } + }) + return dst +} + +// FlipV flips the image vertically (from top to bottom) and returns the transformed image. +func FlipV(img image.Image) *image.NRGBA { + src := newScanner(img) + dstW := src.w + dstH := src.h + rowSize := dstW * 4 + dst := image.NewNRGBA(image.Rect(0, 0, dstW, dstH)) + parallel(0, dstH, func(ys <-chan int) { + for dstY := range ys { + i := dstY * dst.Stride + srcY := dstH - dstY - 1 + src.scan(0, srcY, src.w, srcY+1, dst.Pix[i:i+rowSize]) + } + }) + return dst +} + +// Transpose flips the image horizontally and rotates 90 degrees counter-clockwise. +func Transpose(img image.Image) *image.NRGBA { + src := newScanner(img) + dstW := src.h + dstH := src.w + rowSize := dstW * 4 + dst := image.NewNRGBA(image.Rect(0, 0, dstW, dstH)) + parallel(0, dstH, func(ys <-chan int) { + for dstY := range ys { + i := dstY * dst.Stride + srcX := dstY + src.scan(srcX, 0, srcX+1, src.h, dst.Pix[i:i+rowSize]) + } + }) + return dst +} + +// Transverse flips the image vertically and rotates 90 degrees counter-clockwise. +func Transverse(img image.Image) *image.NRGBA { + src := newScanner(img) + dstW := src.h + dstH := src.w + rowSize := dstW * 4 + dst := image.NewNRGBA(image.Rect(0, 0, dstW, dstH)) + parallel(0, dstH, func(ys <-chan int) { + for dstY := range ys { + i := dstY * dst.Stride + srcX := dstH - dstY - 1 + src.scan(srcX, 0, srcX+1, src.h, dst.Pix[i:i+rowSize]) + reverse(dst.Pix[i : i+rowSize]) + } + }) + return dst +} + +// Rotate90 rotates the image 90 degrees counter-clockwise and returns the transformed image. +func Rotate90(img image.Image) *image.NRGBA { + src := newScanner(img) + dstW := src.h + dstH := src.w + rowSize := dstW * 4 + dst := image.NewNRGBA(image.Rect(0, 0, dstW, dstH)) + parallel(0, dstH, func(ys <-chan int) { + for dstY := range ys { + i := dstY * dst.Stride + srcX := dstH - dstY - 1 + src.scan(srcX, 0, srcX+1, src.h, dst.Pix[i:i+rowSize]) + } + }) + return dst +} + +// Rotate180 rotates the image 180 degrees counter-clockwise and returns the transformed image. +func Rotate180(img image.Image) *image.NRGBA { + src := newScanner(img) + dstW := src.w + dstH := src.h + rowSize := dstW * 4 + dst := image.NewNRGBA(image.Rect(0, 0, dstW, dstH)) + parallel(0, dstH, func(ys <-chan int) { + for dstY := range ys { + i := dstY * dst.Stride + srcY := dstH - dstY - 1 + src.scan(0, srcY, src.w, srcY+1, dst.Pix[i:i+rowSize]) + reverse(dst.Pix[i : i+rowSize]) + } + }) + return dst +} + +// Rotate270 rotates the image 270 degrees counter-clockwise and returns the transformed image. +func Rotate270(img image.Image) *image.NRGBA { + src := newScanner(img) + dstW := src.h + dstH := src.w + rowSize := dstW * 4 + dst := image.NewNRGBA(image.Rect(0, 0, dstW, dstH)) + parallel(0, dstH, func(ys <-chan int) { + for dstY := range ys { + i := dstY * dst.Stride + srcX := dstY + src.scan(srcX, 0, srcX+1, src.h, dst.Pix[i:i+rowSize]) + reverse(dst.Pix[i : i+rowSize]) + } + }) + return dst +} + +// Rotate rotates an image by the given angle counter-clockwise . +// The angle parameter is the rotation angle in degrees. +// The bgColor parameter specifies the color of the uncovered zone after the rotation. +func Rotate(img image.Image, angle float64, bgColor color.Color) *image.NRGBA { + angle = angle - math.Floor(angle/360)*360 + + switch angle { + case 0: + return Clone(img) + case 90: + return Rotate90(img) + case 180: + return Rotate180(img) + case 270: + return Rotate270(img) + } + + src := toNRGBA(img) + srcW := src.Bounds().Max.X + srcH := src.Bounds().Max.Y + dstW, dstH := rotatedSize(srcW, srcH, angle) + dst := image.NewNRGBA(image.Rect(0, 0, dstW, dstH)) + + if dstW <= 0 || dstH <= 0 { + return dst + } + + srcXOff := float64(srcW)/2 - 0.5 + srcYOff := float64(srcH)/2 - 0.5 + dstXOff := float64(dstW)/2 - 0.5 + dstYOff := float64(dstH)/2 - 0.5 + + bgColorNRGBA := color.NRGBAModel.Convert(bgColor).(color.NRGBA) + sin, cos := math.Sincos(math.Pi * angle / 180) + + parallel(0, dstH, func(ys <-chan int) { + for dstY := range ys { + for dstX := 0; dstX < dstW; dstX++ { + xf, yf := rotatePoint(float64(dstX)-dstXOff, float64(dstY)-dstYOff, sin, cos) + xf, yf = xf+srcXOff, yf+srcYOff + interpolatePoint(dst, dstX, dstY, src, xf, yf, bgColorNRGBA) + } + } + }) + + return dst +} + +func rotatePoint(x, y, sin, cos float64) (float64, float64) { + return x*cos - y*sin, x*sin + y*cos +} + +func rotatedSize(w, h int, angle float64) (int, int) { + if w <= 0 || h <= 0 { + return 0, 0 + } + + sin, cos := math.Sincos(math.Pi * angle / 180) + x1, y1 := rotatePoint(float64(w-1), 0, sin, cos) + x2, y2 := rotatePoint(float64(w-1), float64(h-1), sin, cos) + x3, y3 := rotatePoint(0, float64(h-1), sin, cos) + + minx := math.Min(x1, math.Min(x2, math.Min(x3, 0))) + maxx := math.Max(x1, math.Max(x2, math.Max(x3, 0))) + miny := math.Min(y1, math.Min(y2, math.Min(y3, 0))) + maxy := math.Max(y1, math.Max(y2, math.Max(y3, 0))) + + neww := maxx - minx + 1 + if neww-math.Floor(neww) > 0.1 { + neww++ + } + newh := maxy - miny + 1 + if newh-math.Floor(newh) > 0.1 { + newh++ + } + + return int(neww), int(newh) +} + +func interpolatePoint(dst *image.NRGBA, dstX, dstY int, src *image.NRGBA, xf, yf float64, bgColor color.NRGBA) { + dstIndex := dstY*dst.Stride + dstX*4 + + x0 := int(math.Floor(xf)) + y0 := int(math.Floor(yf)) + bounds := src.Bounds() + if !image.Pt(x0, y0).In(image.Rect(bounds.Min.X-1, bounds.Min.Y-1, bounds.Max.X, bounds.Max.Y)) { + dst.Pix[dstIndex+0] = bgColor.R + dst.Pix[dstIndex+1] = bgColor.G + dst.Pix[dstIndex+2] = bgColor.B + dst.Pix[dstIndex+3] = bgColor.A + return + } + + xq := xf - float64(x0) + yq := yf - float64(y0) + + var pxs [4]color.NRGBA + var cfs [4]float64 + + for i := 0; i < 2; i++ { + for j := 0; j < 2; j++ { + k := i*2 + j + pt := image.Pt(x0+j, y0+i) + if pt.In(bounds) { + l := pt.Y*src.Stride + pt.X*4 + pxs[k].R = src.Pix[l+0] + pxs[k].G = src.Pix[l+1] + pxs[k].B = src.Pix[l+2] + pxs[k].A = src.Pix[l+3] + } else { + pxs[k] = bgColor + } + } + } + + cfs[0] = (1 - xq) * (1 - yq) + cfs[1] = xq * (1 - yq) + cfs[2] = (1 - xq) * yq + cfs[3] = xq * yq + + var r, g, b, a float64 + for i := range pxs { + wa := float64(pxs[i].A) * cfs[i] + r += float64(pxs[i].R) * wa + g += float64(pxs[i].G) * wa + b += float64(pxs[i].B) * wa + a += wa + } + + if a != 0 { + r /= a + g /= a + b /= a + } + + dst.Pix[dstIndex+0] = clamp(r) + dst.Pix[dstIndex+1] = clamp(g) + dst.Pix[dstIndex+2] = clamp(b) + dst.Pix[dstIndex+3] = clamp(a) +} diff --git a/vendor/github.com/disintegration/imaging/utils.go b/vendor/github.com/disintegration/imaging/utils.go new file mode 100644 index 0000000..3b6ad2e --- /dev/null +++ b/vendor/github.com/disintegration/imaging/utils.go @@ -0,0 +1,83 @@ +package imaging + +import ( + "image" + "runtime" + "sync" +) + +// parallel processes the data in separate goroutines. +func parallel(start, stop int, fn func(<-chan int)) { + count := stop - start + if count < 1 { + return + } + + procs := runtime.GOMAXPROCS(0) + if procs > count { + procs = count + } + + c := make(chan int, count) + for i := start; i < stop; i++ { + c <- i + } + close(c) + + var wg sync.WaitGroup + for i := 0; i < procs; i++ { + wg.Add(1) + go func() { + defer wg.Done() + fn(c) + }() + } + wg.Wait() +} + +// absint returns the absolute value of i. +func absint(i int) int { + if i < 0 { + return -i + } + return i +} + +// clamp rounds and clamps float64 value to fit into uint8. +func clamp(x float64) uint8 { + v := int64(x + 0.5) + if v > 255 { + return 255 + } + if v > 0 { + return uint8(v) + } + return 0 +} + +func reverse(pix []uint8) { + if len(pix) <= 4 { + return + } + i := 0 + j := len(pix) - 4 + for i < j { + pix[i+0], pix[j+0] = pix[j+0], pix[i+0] + pix[i+1], pix[j+1] = pix[j+1], pix[i+1] + pix[i+2], pix[j+2] = pix[j+2], pix[i+2] + pix[i+3], pix[j+3] = pix[j+3], pix[i+3] + i += 4 + j -= 4 + } +} + +func toNRGBA(img image.Image) *image.NRGBA { + if img, ok := img.(*image.NRGBA); ok { + return &image.NRGBA{ + Pix: img.Pix, + Stride: img.Stride, + Rect: img.Rect.Sub(img.Rect.Min), + } + } + return Clone(img) +} |