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| author | Wim <wim@42.be> | 2020-12-31 14:48:12 +0100 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2020-12-31 14:48:12 +0100 |
| commit | 4f20ebead36876a88391bf033d1de3e4cf0228da (patch) | |
| tree | 70b6fd79c6a5e00c958c29a7bd3926f074e76ba6 /vendor/github.com/disintegration/imaging | |
| parent | a9f89dbc645aafc68daa9fc8d589f55104b535c7 (diff) | |
| download | matterbridge-msglm-4f20ebead36876a88391bf033d1de3e4cf0228da.tar.gz matterbridge-msglm-4f20ebead36876a88391bf033d1de3e4cf0228da.tar.bz2 matterbridge-msglm-4f20ebead36876a88391bf033d1de3e4cf0228da.zip | |
Update vendor for next release (#1343)
Diffstat (limited to 'vendor/github.com/disintegration/imaging')
16 files changed, 2902 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 00000000..7ae5e4b2 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/.travis.yml @@ -0,0 +1,12 @@ +language: go +go: + - "1.10.x" + - "1.11.x" + - "1.12.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 00000000..a4144a9d --- /dev/null +++ b/vendor/github.com/disintegration/imaging/LICENSE @@ -0,0 +1,21 @@ +The MIT License (MIT) + +Copyright (c) 2012 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. diff --git a/vendor/github.com/disintegration/imaging/README.md b/vendor/github.com/disintegration/imaging/README.md new file mode 100644 index 00000000..a1fd764d --- /dev/null +++ b/vendor/github.com/disintegration/imaging/README.md @@ -0,0 +1,226 @@ +# 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, non-premultiplied 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:
+- `Lanczos` - A high-quality resampling filter for photographic images yielding sharp results.
+- `CatmullRom` - A sharp cubic filter that is faster than Lanczos filter while providing similar results.
+- `MitchellNetravali` - A cubic filter that produces smoother results with less ringing artifacts than CatmullRom.
+- `Linear` - Bilinear resampling filter, produces smooth output. 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.
+
+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
+-----------------------------------|----------------------------------------------|---------------------------------------------
+ |  | 
+
+### Saturation adjustment
+
+```go
+dstImage := imaging.AdjustSaturation(srcImage, 20)
+```
+
+Original image | Saturation = 30 | Saturation = -30
+-----------------------------------|----------------------------------------------|---------------------------------------------
+ |  | 
+
+## FAQ
+
+### Incorrect image orientation after processing (e.g. an image appears rotated after resizing)
+
+Most probably, the given image contains the EXIF orientation tag.
+The stadard `image/*` packages do not support loading and saving
+this kind of information. To fix the issue, try opening images with
+the `AutoOrientation` decode option. If this option is set to `true`,
+the image orientation is changed after decoding, according to the
+orientation tag (if present). Here's the example:
+
+```go
+img, err := imaging.Open("test.jpg", imaging.AutoOrientation(true))
+```
+
+### What's the difference between `imaging` and `gift` packages?
+
+[imaging](https://github.com/disintegration/imaging)
+is designed to be a lightweight and simple image manipulation package.
+It provides basic image processing functions and a few helper functions
+such as `Open` and `Save`. It consistently returns *image.NRGBA image
+type (8 bits per channel, RGBA).
+
+[gift](https://github.com/disintegration/gift)
+supports more advanced image processing, for example, sRGB/Linear color
+space conversions. It also supports different output image types
+(e.g. 16 bits per channel) and provides easy-to-use API for chaining
+multiple processing steps together.
+
+## 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:
+
+
diff --git a/vendor/github.com/disintegration/imaging/adjust.go b/vendor/github.com/disintegration/imaging/adjust.go new file mode 100644 index 00000000..daaf1de8 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/adjust.go @@ -0,0 +1,253 @@ +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++ { + d := dst.Pix[i : i+3 : i+3] + r := d[0] + g := d[1] + b := d[2] + f := 0.299*float64(r) + 0.587*float64(g) + 0.114*float64(b) + y := uint8(f + 0.5) + d[0] = y + d[1] = y + d[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++ { + d := dst.Pix[i : i+3 : i+3] + d[0] = 255 - d[0] + d[1] = 255 - d[1] + d[2] = 255 - d[2] + i += 4 + } + } + }) + return dst +} + +// AdjustSaturation changes the saturation of the image using the percentage parameter and returns the adjusted image. +// The percentage must be in the range (-100, 100). +// The percentage = 0 gives the original image. +// The percentage = 100 gives the image with the saturation value doubled for each pixel. +// The percentage = -100 gives the image with the saturation value zeroed for each pixel (grayscale). +// +// Examples: +// dstImage = imaging.AdjustSaturation(srcImage, 25) // Increase image saturation by 25%. +// dstImage = imaging.AdjustSaturation(srcImage, -10) // Decrease image saturation by 10%. +// +func AdjustSaturation(img image.Image, percentage float64) *image.NRGBA { + percentage = math.Min(math.Max(percentage, -100), 100) + multiplier := 1 + percentage/100 + + return AdjustFunc(img, func(c color.NRGBA) color.NRGBA { + h, s, l := rgbToHSL(c.R, c.G, c.B) + s *= multiplier + if s > 1 { + s = 1 + } + r, g, b := hslToRGB(h, s, l) + return color.NRGBA{r, g, b, c.A} + }) +} + +// 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++ { + switch { + case 0 <= v && v <= 1: + lut[i] = clamp((0.5 + (float64(i)/255.0-0.5)*v) * 255.0) + case 1 < v && v < 2: + lut[i] = clamp((0.5 + (float64(i)/255.0-0.5)*(1/(2.0-v))) * 255.0) + default: + 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)) + lut = lut[0:256] + 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++ { + d := dst.Pix[i : i+3 : i+3] + d[0] = lut[d[0]] + d[1] = lut[d[1]] + d[2] = lut[d[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++ { + d := dst.Pix[i : i+4 : i+4] + r := d[0] + g := d[1] + b := d[2] + a := d[3] + c := fn(color.NRGBA{r, g, b, a}) + d[0] = c.R + d[1] = c.G + d[2] = c.B + d[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 00000000..11eddc16 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/convolution.go @@ -0,0 +1,148 @@ +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 + s := src.Pix[off : off+3 : off+3] + r += float64(s[0]) * c.k + g += float64(s[1]) * c.k + b += float64(s[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 + d := dst.Pix[dstOff : dstOff+4 : dstOff+4] + d[0] = clamp(r) + d[1] = clamp(g) + d[2] = clamp(b) + d[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 00000000..c98c9125 --- /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, non-premultiplied 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 00000000..47316b70 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/effects.go @@ -0,0 +1,169 @@ +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. +// +// 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) + scanLineF := make([]float64, len(scanLine)) + for y := range ys { + src.scan(0, y, src.w, y+1, scanLine) + for i, v := range scanLine { + scanLineF[i] = float64(v) + } + 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 + s := scanLineF[i : i+4 : i+4] + wa := s[3] * weight + r += s[0] * wa + g += s[1] * wa + b += s[2] * wa + a += wa + } + if a != 0 { + aInv := 1 / a + j := y*dst.Stride + x*4 + d := dst.Pix[j : j+4 : j+4] + d[0] = clamp(r * aInv) + d[1] = clamp(g * aInv) + d[2] = clamp(b * aInv) + d[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) + scanLineF := make([]float64, len(scanLine)) + for x := range xs { + src.scan(x, 0, x+1, src.h, scanLine) + for i, v := range scanLine { + scanLineF[i] = float64(v) + } + 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 + s := scanLineF[i : i+4 : i+4] + wa := s[3] * weight + r += s[0] * wa + g += s[1] * wa + b += s[2] * wa + a += wa + } + if a != 0 { + aInv := 1 / a + j := y*dst.Stride + x*4 + d := dst.Pix[j : j+4 : j+4] + d[0] = clamp(r * aInv) + d[1] = clamp(g * aInv) + d[2] = clamp(b * aInv) + d[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. +// +// 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/go.mod b/vendor/github.com/disintegration/imaging/go.mod new file mode 100644 index 00000000..a870810e --- /dev/null +++ b/vendor/github.com/disintegration/imaging/go.mod @@ -0,0 +1,3 @@ +module github.com/disintegration/imaging + +require golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8 diff --git a/vendor/github.com/disintegration/imaging/go.sum b/vendor/github.com/disintegration/imaging/go.sum new file mode 100644 index 00000000..17bf7381 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/go.sum @@ -0,0 +1,3 @@ +golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8 h1:hVwzHzIUGRjiF7EcUjqNxk3NCfkPxbDKRdnNE1Rpg0U= +golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0= +golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ= diff --git a/vendor/github.com/disintegration/imaging/histogram.go b/vendor/github.com/disintegration/imaging/histogram.go new file mode 100644 index 00000000..c547fe82 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/histogram.go @@ -0,0 +1,52 @@ +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++ { + s := scanLine[i : i+3 : i+3] + r := s[0] + g := s[1] + b := s[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/io.go b/vendor/github.com/disintegration/imaging/io.go new file mode 100644 index 00000000..f6c6da86 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/io.go @@ -0,0 +1,444 @@ +package imaging + +import ( + "encoding/binary" + "errors" + "image" + "image/draw" + "image/gif" + "image/jpeg" + "image/png" + "io" + "io/ioutil" + "os" + "path/filepath" + "strings" + + "golang.org/x/image/bmp" + "golang.org/x/image/tiff" +) + +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{} + +type decodeConfig struct { + autoOrientation bool +} + +var defaultDecodeConfig = decodeConfig{ + autoOrientation: false, +} + +// DecodeOption sets an optional parameter for the Decode and Open functions. +type DecodeOption func(*decodeConfig) + +// AutoOrientation returns a DecodeOption that sets the auto-orientation mode. +// If auto-orientation is enabled, the image will be transformed after decoding +// according to the EXIF orientation tag (if present). By default it's disabled. +func AutoOrientation(enabled bool) DecodeOption { + return func(c *decodeConfig) { + c.autoOrientation = enabled + } +} + +// Decode reads an image from r. +func Decode(r io.Reader, opts ...DecodeOption) (image.Image, error) { + cfg := defaultDecodeConfig + for _, option := range opts { + option(&cfg) + } + + if !cfg.autoOrientation { + img, _, err := image.Decode(r) + return img, err + } + + var orient orientation + pr, pw := io.Pipe() + r = io.TeeReader(r, pw) + done := make(chan struct{}) + go func() { + defer close(done) + orient = readOrientation(pr) + io.Copy(ioutil.Discard, pr) + }() + + img, _, err := image.Decode(r) + pw.Close() + <-done + if err != nil { + return nil, err + } + + return fixOrientation(img, orient), nil +} + +// Open loads an image from file. +// +// Examples: +// +// // Load an image from file. +// img, err := imaging.Open("test.jpg") +// +// // Load an image and transform it depending on the EXIF orientation tag (if present). +// img, err := imaging.Open("test.jpg", imaging.AutoOrientation(true)) +// +func Open(filename string, opts ...DecodeOption) (image.Image, error) { + file, err := fs.Open(filename) + if err != nil { + return nil, err + } + defer file.Close() + return Decode(file, opts...) +} + +// Format is an image file format. +type Format int + +// Image file formats. +const ( + JPEG Format = iota + PNG + GIF + TIFF + BMP +) + +var formatExts = map[string]Format{ + "jpg": JPEG, + "jpeg": JPEG, + "png": PNG, + "gif": GIF, + "tif": TIFF, + "tiff": TIFF, + "bmp": BMP, +} + +var formatNames = map[Format]string{ + JPEG: "JPEG", + PNG: "PNG", + GIF: "GIF", + TIFF: "TIFF", + BMP: "BMP", +} + +func (f Format) String() string { + return formatNames[f] +} + +// ErrUnsupportedFormat means the given image format is not supported. +var ErrUnsupportedFormat = errors.New("imaging: unsupported image format") + +// FormatFromExtension parses image format from filename extension: +// "jpg" (or "jpeg"), "png", "gif", "tif" (or "tiff") and "bmp" are supported. +func FormatFromExtension(ext string) (Format, error) { + if f, ok := formatExts[strings.ToLower(strings.TrimPrefix(ext, "."))]; ok { + return f, nil + } + return -1, ErrUnsupportedFormat +} + +// FormatFromFilename parses image format from filename: +// "jpg" (or "jpeg"), "png", "gif", "tif" (or "tiff") and "bmp" are supported. +func FormatFromFilename(filename string) (Format, error) { + ext := filepath.Ext(filename) + return FormatFromExtension(ext) +} + +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) + } + + switch format { + case JPEG: + if nrgba, ok := img.(*image.NRGBA); ok && nrgba.Opaque() { + rgba := &image.RGBA{ + Pix: nrgba.Pix, + Stride: nrgba.Stride, + Rect: nrgba.Rect, + } + return jpeg.Encode(w, rgba, &jpeg.Options{Quality: cfg.jpegQuality}) + } + return jpeg.Encode(w, img, &jpeg.Options{Quality: cfg.jpegQuality}) + + case PNG: + encoder := png.Encoder{CompressionLevel: cfg.pngCompressionLevel} + return encoder.Encode(w, img) + + case GIF: + return gif.Encode(w, img, &gif.Options{ + NumColors: cfg.gifNumColors, + Quantizer: cfg.gifQuantizer, + Drawer: cfg.gifDrawer, + }) + + case TIFF: + return tiff.Encode(w, img, &tiff.Options{Compression: tiff.Deflate, Predictor: true}) + + case BMP: + return bmp.Encode(w, img) + } + + return ErrUnsupportedFormat +} + +// 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) { + f, err := FormatFromFilename(filename) + if err != nil { + return err + } + file, err := fs.Create(filename) + if err != nil { + return err + } + err = Encode(file, img, f, opts...) + errc := file.Close() + if err == nil { + err = errc + } + return err +} + +// orientation is an EXIF flag that specifies the transformation +// that should be applied to image to display it correctly. +type orientation int + +const ( + orientationUnspecified = 0 + orientationNormal = 1 + orientationFlipH = 2 + orientationRotate180 = 3 + orientationFlipV = 4 + orientationTranspose = 5 + orientationRotate270 = 6 + orientationTransverse = 7 + orientationRotate90 = 8 +) + +// readOrientation tries to read the orientation EXIF flag from image data in r. +// If the EXIF data block is not found or the orientation flag is not found +// or any other error occures while reading the data, it returns the +// orientationUnspecified (0) value. +func readOrientation(r io.Reader) orientation { + const ( + markerSOI = 0xffd8 + markerAPP1 = 0xffe1 + exifHeader = 0x45786966 + byteOrderBE = 0x4d4d + byteOrderLE = 0x4949 + orientationTag = 0x0112 + ) + + // Check if JPEG SOI marker is present. + var soi uint16 + if err := binary.Read(r, binary.BigEndian, &soi); err != nil { + return orientationUnspecified + } + if soi != markerSOI { + return orientationUnspecified // Missing JPEG SOI marker. + } + + // Find JPEG APP1 marker. + for { + var marker, size uint16 + if err := binary.Read(r, binary.BigEndian, &marker); err != nil { + return orientationUnspecified + } + if err := binary.Read(r, binary.BigEndian, &size); err != nil { + return orientationUnspecified + } + if marker>>8 != 0xff { + return orientationUnspecified // Invalid JPEG marker. + } + if marker == markerAPP1 { + break + } + if size < 2 { + return orientationUnspecified // Invalid block size. + } + if _, err := io.CopyN(ioutil.Discard, r, int64(size-2)); err != nil { + return orientationUnspecified + } + } + + // Check if EXIF header is present. + var header uint32 + if err := binary.Read(r, binary.BigEndian, &header); err != nil { + return orientationUnspecified + } + if header != exifHeader { + return orientationUnspecified + } + if _, err := io.CopyN(ioutil.Discard, r, 2); err != nil { + return orientationUnspecified + } + + // Read byte order information. + var ( + byteOrderTag uint16 + byteOrder binary.ByteOrder + ) + if err := binary.Read(r, binary.BigEndian, &byteOrderTag); err != nil { + return orientationUnspecified + } + switch byteOrderTag { + case byteOrderBE: + byteOrder = binary.BigEndian + case byteOrderLE: + byteOrder = binary.LittleEndian + default: + return orientationUnspecified // Invalid byte order flag. + } + if _, err := io.CopyN(ioutil.Discard, r, 2); err != nil { + return orientationUnspecified + } + + // Skip the EXIF offset. + var offset uint32 + if err := binary.Read(r, byteOrder, &offset); err != nil { + return orientationUnspecified + } + if offset < 8 { + return orientationUnspecified // Invalid offset value. + } + if _, err := io.CopyN(ioutil.Discard, r, int64(offset-8)); err != nil { + return orientationUnspecified + } + + // Read the number of tags. + var numTags uint16 + if err := binary.Read(r, byteOrder, &numTags); err != nil { + return orientationUnspecified + } + + // Find the orientation tag. + for i := 0; i < int(numTags); i++ { + var tag uint16 + if err := binary.Read(r, byteOrder, &tag); err != nil { + return orientationUnspecified + } + if tag != orientationTag { + if _, err := io.CopyN(ioutil.Discard, r, 10); err != nil { + return orientationUnspecified + } + continue + } + if _, err := io.CopyN(ioutil.Discard, r, 6); err != nil { + return orientationUnspecified + } + var val uint16 + if err := binary.Read(r, byteOrder, &val); err != nil { + return orientationUnspecified + } + if val < 1 || val > 8 { + return orientationUnspecified // Invalid tag value. + } + return orientation(val) + } + return orientationUnspecified // Missing orientation tag. +} + +// fixOrientation applies a transform to img corresponding to the given orientation flag. +func fixOrientation(img image.Image, o orientation) image.Image { + switch o { + case orientationNormal: + case orientationFlipH: + img = FlipH(img) + case orientationFlipV: + img = FlipV(img) + case orientationRotate90: + img = Rotate90(img) + case orientationRotate180: + img = Rotate180(img) + case orientationRotate270: + img = Rotate270(img) + case orientationTranspose: + img = Transpose(img) + case orientationTransverse: + img = Transverse(img) + } + return img +} diff --git a/vendor/github.com/disintegration/imaging/resize.go b/vendor/github.com/disintegration/imaging/resize.go new file mode 100644 index 00000000..706435e3 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/resize.go @@ -0,0 +1,595 @@ +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. +// +// 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 := range weights { + var r, g, b, a float64 + for _, w := range weights[x] { + i := w.index * 4 + s := scanLine[i : i+4 : i+4] + aw := float64(s[3]) * w.weight + r += float64(s[0]) * aw + g += float64(s[1]) * aw + b += float64(s[2]) * aw + a += aw + } + if a != 0 { + aInv := 1 / a + j := j0 + x*4 + d := dst.Pix[j : j+4 : j+4] + d[0] = clamp(r * aInv) + d[1] = clamp(g * aInv) + d[2] = clamp(b * aInv) + d[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 := range weights { + var r, g, b, a float64 + for _, w := range weights[y] { + i := w.index * 4 + s := scanLine[i : i+4 : i+4] + aw := float64(s[3]) * w.weight + r += float64(s[0]) * aw + g += float64(s[1]) * aw + b += float64(s[2]) * aw + a += aw + } + if a != 0 { + aInv := 1 / a + j := y*dst.Stride + x*4 + d := dst.Pix[j : j+4 : j+4] + d[0] = clamp(r * aInv) + d[1] = clamp(g * aInv) + d[2] = clamp(b * aInv) + d[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. +// +// 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 creates an image with the specified dimensions and fills it with the scaled source image. +// To achieve the correct aspect ratio without stretching, the source image will be cropped. +// +// 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 { + dstW, dstH := width, height + + if dstW <= 0 || dstH <= 0 { + return &image.NRGBA{} + } + + srcBounds := img.Bounds() + srcW := srcBounds.Dx() + srcH := srcBounds.Dy() + + if srcW <= 0 || srcH <= 0 { + return &image.NRGBA{} + } + + if srcW == dstW && srcH == dstH { + return Clone(img) + } + + if srcW >= 100 && srcH >= 100 { + return cropAndResize(img, dstW, dstH, anchor, filter) + } + return resizeAndCrop(img, dstW, dstH, anchor, filter) +} + +// cropAndResize crops the image to the smallest possible size that has the required aspect ratio using +// the given anchor point, then scales it to the specified dimensions and returns the transformed image. +// +// This is generally faster than resizing first, but may result in inaccuracies when used on small source images. +func cropAndResize(img image.Image, width, height int, anchor Anchor, filter ResampleFilter) *image.NRGBA { + dstW, dstH := width, height + + srcBounds := img.Bounds() + srcW := srcBounds.Dx() + srcH := srcBounds.Dy() + srcAspectRatio := float64(srcW) / float64(srcH) + dstAspectRatio := float64(dstW) / float64(dstH) + + var tmp *image.NRGBA + if srcAspectRatio < dstAspectRatio { + cropH := float64(srcW) * float64(dstH) / float64(dstW) + tmp = CropAnchor(img, srcW, int(math.Max(1, cropH)+0.5), anchor) + } else { + cropW := float64(srcH) * float64(dstW) / float64(dstH) + tmp = CropAnchor(img, int(math.Max(1, cropW)+0.5), srcH, anchor) + } + + return Resize(tmp, dstW, dstH, filter) +} + +// resizeAndCrop resizes 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. +func resizeAndCrop(img image.Image, width, height int, anchor Anchor, filter ResampleFilter) *image.NRGBA { + dstW, dstH := width, height + + srcBounds := img.Bounds() + srcW := srcBounds.Dx() + srcH := srcBounds.Dy() + srcAspectRatio := float64(srcW) / float64(srcH) + dstAspectRatio := float64(dstW) / float64(dstH) + + var tmp *image.NRGBA + if srcAspectRatio < dstAspectRatio { + tmp = Resize(img, dstW, 0, filter) + } else { + tmp = Resize(img, 0, dstH, filter) + } + + return CropAnchor(tmp, dstW, dstH, 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. +// +// 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 specifies a resampling filter to be used for image resizing. +// +// General filter recommendations: +// +// - Lanczos +// A high-quality resampling filter for photographic images yielding sharp results. +// +// - CatmullRom +// A sharp cubic filter that is faster than Lanczos filter while providing similar results. +// +// - MitchellNetravali +// A cubic filter that produces smoother results with less ringing artifacts than CatmullRom. +// +// - Linear +// Bilinear resampling filter, produces a smooth output. 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 00000000..37d92cef --- /dev/null +++ b/vendor/github.com/disintegration/imaging/scanner.go @@ -0,0 +1,285 @@ +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 + if size == 4 { + for y := y1; y < y2; y++ { + d := dst[j : j+4 : j+4] + s := img.Pix[i : i+4 : i+4] + d[0] = s[0] + d[1] = s[1] + d[2] = s[2] + d[3] = s[3] + j += size + i += img.Stride + } + } else { + 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++ { + s := img.Pix[i : i+8 : i+8] + d := dst[j : j+4 : j+4] + d[0] = s[0] + d[1] = s[2] + d[2] = s[4] + d[3] = s[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++ { + d := dst[j : j+4 : j+4] + a := img.Pix[i+3] + switch a { + case 0: + d[0] = 0 + d[1] = 0 + d[2] = 0 + d[3] = a + case 0xff: + s := img.Pix[i : i+4 : i+4] + d[0] = s[0] + d[1] = s[1] + d[2] = s[2] + d[3] = a + default: + s := img.Pix[i : i+4 : i+4] + r16 := uint16(s[0]) + g16 := uint16(s[1]) + b16 := uint16(s[2]) + a16 := uint16(a) + d[0] = uint8(r16 * 0xff / a16) + d[1] = uint8(g16 * 0xff / a16) + d[2] = uint8(b16 * 0xff / a16) + d[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++ { + s := img.Pix[i : i+8 : i+8] + d := dst[j : j+4 : j+4] + a := s[6] + switch a { + case 0: + d[0] = 0 + d[1] = 0 + d[2] = 0 + case 0xff: + d[0] = s[0] + d[1] = s[2] + d[2] = s[4] + default: + r32 := uint32(s[0])<<8 | uint32(s[1]) + g32 := uint32(s[2])<<8 | uint32(s[3]) + b32 := uint32(s[4])<<8 | uint32(s[5]) + a32 := uint32(s[6])<<8 | uint32(s[7]) + d[0] = uint8((r32 * 0xffff / a32) >> 8) + d[1] = uint8((g32 * 0xffff / a32) >> 8) + d[2] = uint8((b32 * 0xffff / a32) >> 8) + } + d[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] + d := dst[j : j+4 : j+4] + d[0] = c + d[1] = c + d[2] = c + d[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] + d := dst[j : j+4 : j+4] + d[0] = c + d[1] = c + d[2] = c + d[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 + + hy := img.Rect.Min.Y / 2 + hx := img.Rect.Min.X / 2 + for y := y1; y < y2; y++ { + iy := (y-img.Rect.Min.Y)*img.YStride + (x1 - img.Rect.Min.X) + + var yBase int + switch img.SubsampleRatio { + case image.YCbCrSubsampleRatio444, image.YCbCrSubsampleRatio422: + yBase = (y - img.Rect.Min.Y) * img.CStride + case image.YCbCrSubsampleRatio420, image.YCbCrSubsampleRatio440: + yBase = (y/2 - hy) * img.CStride + } + + for x := x1; x < x2; x++ { + var ic int + switch img.SubsampleRatio { + case image.YCbCrSubsampleRatio444, image.YCbCrSubsampleRatio440: + ic = yBase + (x - img.Rect.Min.X) + case image.YCbCrSubsampleRatio422, image.YCbCrSubsampleRatio420: + ic = yBase + (x/2 - hx) + default: + ic = img.COffset(x, y) + } + + yy1 := int32(img.Y[iy]) * 0x10101 + cb1 := int32(img.Cb[ic]) - 128 + cr1 := int32(img.Cr[ic]) - 128 + + r := yy1 + 91881*cr1 + if uint32(r)&0xff000000 == 0 { + r >>= 16 + } else { + r = ^(r >> 31) + } + + g := yy1 - 22554*cb1 - 46802*cr1 + if uint32(g)&0xff000000 == 0 { + g >>= 16 + } else { + g = ^(g >> 31) + } + + b := yy1 + 116130*cb1 + if uint32(b)&0xff000000 == 0 { + b >>= 16 + } else { + b = ^(b >> 31) + } + + d := dst[j : j+4 : j+4] + d[0] = uint8(r) + d[1] = uint8(g) + d[2] = uint8(b) + d[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]] + d := dst[j : j+4 : j+4] + d[0] = c.R + d[1] = c.G + d[2] = c.B + d[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() + d := dst[j : j+4 : j+4] + switch a16 { + case 0xffff: + d[0] = uint8(r16 >> 8) + d[1] = uint8(g16 >> 8) + d[2] = uint8(b16 >> 8) + d[3] = 0xff + case 0: + d[0] = 0 + d[1] = 0 + d[2] = 0 + d[3] = 0 + default: + d[0] = uint8(((r16 * 0xffff) / a16) >> 8) + d[1] = uint8(((g16 * 0xffff) / a16) >> 8) + d[2] = uint8(((b16 * 0xffff) / a16) >> 8) + d[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 00000000..0ec19a03 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/tools.go @@ -0,0 +1,249 @@ +package imaging + +import ( + "bytes" + "image" + "image/color" + "math" +) + +// 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{} + } + + c := color.NRGBAModel.Convert(fillColor).(color.NRGBA) + if (c == color.NRGBA{0, 0, 0, 0}) { + return image.NewNRGBA(image.Rect(0, 0, width, height)) + } + + return &image.NRGBA{ + Pix: bytes.Repeat([]byte{c.R, c.G, c.B, c.A}, width*height), + Stride: 4 * width, + Rect: image.Rect(0, 0, width, height), + } +} + +// 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 +} + +// 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. +// +// 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++ { + d := dst.Pix[i : i+4 : i+4] + r1 := float64(d[0]) + g1 := float64(d[1]) + b1 := float64(d[2]) + a1 := float64(d[3]) + + s := scanLine[j : j+4 : j+4] + r2 := float64(s[0]) + g2 := float64(s[1]) + b2 := float64(s[2]) + a2 := float64(s[3]) + + coef2 := opacity * a2 / 255 + coef1 := (1 - coef2) * a1 / 255 + coefSum := coef1 + coef2 + coef1 /= coefSum + coef2 /= coefSum + + d[0] = uint8(r1*coef1 + r2*coef2) + d[1] = uint8(g1*coef1 + g2*coef2) + d[2] = uint8(b1*coef1 + b2*coef2) + d[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 00000000..fe4a92f9 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/transform.go @@ -0,0 +1,268 @@ +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) { + j := dstY*dst.Stride + dstX*4 + d := dst.Pix[j : j+4 : j+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)) { + d[0] = bgColor.R + d[1] = bgColor.G + d[2] = bgColor.B + d[3] = bgColor.A + return + } + + xq := xf - float64(x0) + yq := yf - float64(y0) + points := [4]image.Point{ + {x0, y0}, + {x0 + 1, y0}, + {x0, y0 + 1}, + {x0 + 1, y0 + 1}, + } + weights := [4]float64{ + (1 - xq) * (1 - yq), + xq * (1 - yq), + (1 - xq) * yq, + xq * yq, + } + + var r, g, b, a float64 + for i := 0; i < 4; i++ { + p := points[i] + w := weights[i] + if p.In(bounds) { + i := p.Y*src.Stride + p.X*4 + s := src.Pix[i : i+4 : i+4] + wa := float64(s[3]) * w + r += float64(s[0]) * wa + g += float64(s[1]) * wa + b += float64(s[2]) * wa + a += wa + } else { + wa := float64(bgColor.A) * w + r += float64(bgColor.R) * wa + g += float64(bgColor.G) * wa + b += float64(bgColor.B) * wa + a += wa + } + } + if a != 0 { + aInv := 1 / a + d[0] = clamp(r * aInv) + d[1] = clamp(g * aInv) + d[2] = clamp(b * aInv) + d[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 00000000..6c7af1a5 --- /dev/null +++ b/vendor/github.com/disintegration/imaging/utils.go @@ -0,0 +1,167 @@ +package imaging + +import ( + "image" + "math" + "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 { + pi := pix[i : i+4 : i+4] + pj := pix[j : j+4 : j+4] + pi[0], pj[0] = pj[0], pi[0] + pi[1], pj[1] = pj[1], pi[1] + pi[2], pj[2] = pj[2], pi[2] + pi[3], pj[3] = pj[3], pi[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) +} + +// rgbToHSL converts a color from RGB to HSL. +func rgbToHSL(r, g, b uint8) (float64, float64, float64) { + rr := float64(r) / 255 + gg := float64(g) / 255 + bb := float64(b) / 255 + + max := math.Max(rr, math.Max(gg, bb)) + min := math.Min(rr, math.Min(gg, bb)) + + l := (max + min) / 2 + + if max == min { + return 0, 0, l + } + + var h, s float64 + d := max - min + if l > 0.5 { + s = d / (2 - max - min) + } else { + s = d / (max + min) + } + + switch max { + case rr: + h = (gg - bb) / d + if g < b { + h += 6 + } + case gg: + h = (bb-rr)/d + 2 + case bb: + h = (rr-gg)/d + 4 + } + h /= 6 + + return h, s, l +} + +// hslToRGB converts a color from HSL to RGB. +func hslToRGB(h, s, l float64) (uint8, uint8, uint8) { + var r, g, b float64 + if s == 0 { + v := clamp(l * 255) + return v, v, v + } + + var q float64 + if l < 0.5 { + q = l * (1 + s) + } else { + q = l + s - l*s + } + p := 2*l - q + + r = hueToRGB(p, q, h+1/3.0) + g = hueToRGB(p, q, h) + b = hueToRGB(p, q, h-1/3.0) + + return clamp(r * 255), clamp(g * 255), clamp(b * 255) +} + +func hueToRGB(p, q, t float64) float64 { + if t < 0 { + t++ + } + if t > 1 { + t-- + } + if t < 1/6.0 { + return p + (q-p)*6*t + } + if t < 1/2.0 { + return q + } + if t < 2/3.0 { + return p + (q-p)*(2/3.0-t)*6 + } + return p +} |