gotosocial/vendor/github.com/buckket/go-blurhash/utils.go
Tobi Smethurst 98263a7de6
Grand test fixup (#138)
* start fixing up tests

* fix up tests + automate with drone

* fiddle with linting

* messing about with drone.yml

* some more fiddling

* hmmm

* add cache

* add vendor directory

* verbose

* ci updates

* update some little things

* update sig
2021-08-12 21:03:24 +02:00

23 lines
480 B
Go

package blurhash
import "math"
func linearTosRGB(value float64) int {
v := math.Max(0, math.Min(1, value))
if v <= 0.0031308 {
return int(v*12.92*255 + 0.5)
}
return int((1.055*math.Pow(v, 1/2.4)-0.055)*255 + 0.5)
}
func sRGBToLinear(value int) float64 {
v := float64(value) / 255
if v <= 0.04045 {
return v / 12.92
}
return math.Pow((v+0.055)/1.055, 2.4)
}
func signPow(value, exp float64) float64 {
return math.Copysign(math.Pow(math.Abs(value), exp), value)
}