func Vis(feat *rimg64.Multi, weights WeightSet, cell int) image.Image {
if feat.Channels == 31 {
return Vis(compress(feat, weights), weights, cell)
}
width, height := feat.Width*cell, feat.Height*cell
img := image.NewRGBA(image.Rect(0, 0, width, height))
// Fill background.
bg := color.Gray{0}
if weights == Signed {
bg = color.Gray{128}
}
draw.Draw(img, img.Bounds(), image.NewUniform(bg), image.ZP, draw.Src)
// Rescale intensities to [0, 1].
var dst vec.Mutable = vec.Slice(feat.Elems)
var src vec.Const = dst
if weights == Signed {
max, _ := vec.Max(vec.Abs(src))
rescale := func(x float64) float64 {
return (1 + x/max) / 2
}
vec.Copy(dst, vec.Map(src, rescale))
} else {
switch weights {
case Neg:
src = vec.Scale(-1, src)
case Abs:
src = vec.Abs(src)
default:
}
max, _ := vec.Max(src)
if max <= 0 {
vec.Copy(dst, vec.Zeros(src.Len()))
} else {
rescale := func(x float64) float64 {
return math.Max(0, x/max)
}
vec.Copy(dst, vec.Map(src, rescale))
}
}
gc := draw2d.NewGraphicContext(img)
gc.SetLineWidth(1)
// Draw cells.
for x := 0; x < feat.Width; x++ {
for y := 0; y < feat.Height; y++ {
drawCell(feat, x, y, gc, cell)
}
}
return img
}
func InfNorm(x Const) float64 {
y, _ := vec.Max(Abs(x))
return y
}