func (this *DWT_CDF_9_7) Inverse(src, dst []int) (uint, uint, error) {
if len(src) < int(this.width*this.height) {
return 0, 0, errors.New("The input buffer is too small")
}
if len(dst) < int(this.width*this.height) {
return 0, 0, errors.New("The output buffer is too small")
}
if kanzi.SameIntSlices(src, dst, false) == false {
copy(dst, src)
}
i := this.steps - 1
for {
// First horizontal transform
this.computeInverse(dst, 1, this.width, this.height>>i, this.width>>i)
// Then vertical transform on the updated signal
this.computeInverse(dst, this.width, 1, this.width>>i, this.height>>i)
if i == 0 {
break
}
i--
}
return this.width * this.height, this.width * this.height, nil
}
func (this *DWT_CDF_9_7) Forward(src, dst []int) (uint, uint, error) {
if len(src) < int(this.width*this.height) {
return 0, 0, errors.New("The input buffer is too small")
}
if len(dst) < int(this.width*this.height) {
return 0, 0, errors.New("The output buffer is too small")
}
if kanzi.SameIntSlices(src, dst, false) == false {
copy(dst, src)
}
for i := uint(0); i < this.steps; i++ {
// First, vertical transform
this.computeForward(dst, this.width, 1, this.width>>i, this.height>>i)
// Then horizontal transform on the updated signal
this.computeForward(dst, 1, this.width, this.height>>i, this.width>>i)
}
return this.width * this.height, this.width * this.height, nil
}