PresentationApp/imagick.go
2016-03-27 13:01:51 -07:00

90 lines
2.5 KiB
Go

// PresentationApp project imagick.go
package main
import (
"image"
. "math"
"gopkg.in/gographics/imagick.v2/imagick"
)
/*resizeImage() mw fullsize image
newwidth, newheight = size to be resized to
keepSpecSize = return image with exactly the size specified or just the size of the resized image
center = senter the image
*/
func resizeImage(mw *imagick.MagickWand, newWidth, newHeight int, keepSpecSize, center bool) (resmw *imagick.MagickWand) {
var (
width, height, origHeight, origWidth int
)
origHeight = int(mw.GetImageHeight())
origWidth = int(mw.GetImageWidth())
//check if requested size is the same as current size
if (origHeight != newHeight) || (origWidth != newWidth) {
// width / height * newheight = newwidth
if (round((float64(origWidth) / float64(origHeight)) * float64(newHeight))) <= newWidth {
width = round((float64(origWidth) / float64(origHeight)) * float64(newHeight))
height = newHeight
} else {
// height / width * newwidth = newheight
height = round((float64(origHeight) / float64(origWidth)) * float64(newWidth))
width = newWidth
}
} else {
height = newHeight
width = newWidth
}
//new magickwand for resized image
resmw = imagick.NewMagickWand()
if !keepSpecSize {
resmw.NewImage(uint(width), uint(height), imagick.NewPixelWand())
center = false
} else {
//blank image
resmw.NewImage(uint(newWidth), uint(newHeight), imagick.NewPixelWand())
if center {
err = mw.ResizeImage(uint(width), uint(height), imagick.FILTER_LANCZOS, 1)
if err != nil {
panic(err)
}
//centers image
resmw.CompositeImage(mw, imagick.COMPOSITE_OP_SRC_OVER, round(float64(newWidth-width)/float64(2)), round(float64(newHeight-height)/float64(2)))
} else {
resmw.CompositeImage(mw, imagick.COMPOSITE_OP_SRC_OVER, 0, 0)
}
}
mw.Destroy()
return resmw
}
//getImage() from imagick to image.RGBA
func (cl cell) getImage(width, height int) (img *image.RGBA) {
mw := cl.img.GetImage()
if (width == 0) || (height == 0) {
width = int(mw.GetImageWidth())
height = int(mw.GetImageHeight())
}
mw = resizeImage(mw, width, height, true, true)
img = image.NewRGBA(image.Rect(0, 0, int(width), int(height)))
if img.Stride != img.Rect.Size().X*4 {
panic("unsupported stride")
}
Tpix, _ := mw.ExportImagePixels(0, 0, uint(width), uint(height), "RGBA", imagick.PIXEL_CHAR)
img.Pix = Tpix.([]uint8)
mw.Destroy()
return
}
func round(a float64) int {
if a < 0 {
return int(Ceil(a - 0.5))
}
return int(Floor(a + 0.5))
}