func ToComputeImage(src image.Image) *image.Gray {
// Small M
bSize := src.Bounds().Size()
smallBounds := image.Rect(0, 0, bSize.X/16, bSize.Y/16)
smallM := image.NewGray(smallBounds)
rez.Convert(smallM, src, rez.NewBilinearFilter())
return smallM
}
func ToComputeImageCol(src image.Image) *image.RGBA {
// Small M
//bSize := src.Bounds().Size()
smallBounds := src.Bounds() // image.Rect(0, 0, bSize.X/16, bSize.Y/16)
smallM := image.NewRGBA(smallBounds)
rez.Convert(smallM, src, rez.NewBilinearFilter())
return smallM
}
func newResizeFuncRez(filter rez.Filter) resizeFunc {
return func(im image.Image) image.Image {
newIm := newImageFunc(image.Rect(0, 0, width, height))
err := rez.Convert(newIm, im, filter)
if err != nil {
panic(err)
}
return newIm
}
}
// ResizeImage resizes the given image IF it is larger than maxWidth or maxHeight
func ResizeImage(src image.Image, maxWidth int64, maxHeight int64, square bool) (image.Image, error) {
var dst image.Image
// Check the original dimensions first, and bail out if this image is not larger than max dimensions
srcSize := src.Bounds().Size()
if int64(srcSize.X) < maxWidth && int64(srcSize.Y) < maxHeight {
return src, nil
}
// Use the original image dimensions to keep it in pro
// Distorting images is a sin of which we are never guilty
ratio := float64(maxWidth) / float64(srcSize.X)
yRatio := float64(maxHeight) / float64(srcSize.Y)
if yRatio < ratio {
ratio = yRatio
}
// Now adjust desired width and height according to ratio
width := float64(srcSize.X) * ratio
height := float64(srcSize.Y) * ratio
// Create a new resized image with the desired dimensions and fill it with resized image data
// We switch on input image type - is YCbCrSubsampleRatio444 correct?
switch src.(type) {
case *image.YCbCr:
dst = image.NewYCbCr(image.Rect(0, 0, int(width), int(height)), image.YCbCrSubsampleRatio444)
case *image.RGBA:
dst = image.NewRGBA(image.Rect(0, 0, int(width), int(height)))
default:
dst = nil
}
err := rez.Convert(dst, src, rez.NewBicubicFilter())
// IF we want thumbnails to be square/cropped we could do this
// for now we don't need this. We may not even want it for camping?
// err := imaging.Thumbnail(srcImage, 100, 100, imaging.Lanczos)
if err != nil {
return nil, err
}
return dst, nil
}
func ConvertThreads(output, input image.Image, filter rez.Filter) error {
return rez.Convert(output, input, filter)
}