image linear trnsformations

linTransform.fsx

#r "System.Drawing.dll"
module Bitmap =
    open System
    open System.IO
    open System.Drawing
    open System.Drawing.Imaging

    let toArray (image:Bitmap) =
        Array2D.init image.Width image.Height (fun i j -> image.GetPixel(i,j))
    
    type DynamicImage = (int*int*Color)[]

    let dynamicToArray (image : DynamicImage) = 
        let minX = image |> Array.map (fun (x,_,_) -> x) |> Array.min
        let maxX = image |> Array.map (fun (x,_,_) -> x) |> Array.max
        let minY = image |> Array.map (fun (_,y,_) -> y) |> Array.min
        let maxY = image |> Array.map (fun (_,y,_) -> y) |> Array.max
        let lenX = maxX - minX + 1
        let lenY = maxY - minY + 1
        printfn "out size %d %d" lenX lenY 
        let res = Array2D.zeroCreate lenX lenY
        for (x,y,c) in image do
            let x = x - minX
            let y = y - minY
            //printfn "set %d %d" x y 
            res.[x, y] <- c
        res

    let fromArray (arr : Color[,]) =
        let w,h = Array2D.length1 arr, Array2D.length2 arr
        let res = new Bitmap (w,h)
        Array2D.iteri (fun i j c -> res.SetPixel(i,j,c)) arr
        res

    let load path : Bitmap = downcast Image.FromFile(path, true)
    let save path (image : Bitmap) = image.Save path

    

module Transformations = 
    type Transformation = float[,]
    type Vector = float[]
    let apply (trans:Transformation) (v:Vector) =
        let res = Array.create (Array2D.length1 trans) 0.0
        for j in 0..(Array2D.length1 trans - 1) do
            for i in 0..(v.Length - 1) do
                res.[j] <- res.[j] + trans.[j,i] * v.[i]
        res

open Transformations
open Bitmap
let transformImage (trans:Transformation) step img  = 
    let arr = img |> toArray
    let res = ResizeArray()
    for i in 0.0..step..(float(Array2D.length1 arr - 1)) do
        for j in 0.0..step..(float(Array2D.length2 arr - 1)) do
            let [|x;y|] = apply trans [|float i;float j|]
            res.Add(int x, int y, arr.[int i,int j])
    res.ToArray() |> dynamicToArray |> fromArray 


let transformFile (trans:Transformation) step inImagePath outImagePath  = 
    let res = load inImagePath |> transformImage trans step
    save outImagePath res
    


//apply (array2D [|[|2.0;1.0|];[|0.0;1.0|]|]) [|1.0;2.0|]

open System.Drawing
open System.Windows.Forms
open System.Threading

let mutable img = load "D:\\tmp\\leo.jpg"
let form = new Form(Visible = true, TopMost = true, Width = img.Width, Height = img.Height)
form.BackgroundImage <- transformImage (array2D [|[|2.0;1.0|];[|0.0;1.0|]|]) 0.1 img :> Image
form.Size = form.BackgroundImage.Size;