Split image into X parts

Questions
1

I got an image with the size of eg. (64, 16), Can I split it into x images 16x16? Same with (64, 32)?
Basically, how to go on, so it would require less time. I tried using image:copy(x,y,w,h) but i guess i use it wrong.

2

Here’s an example to split an image.

function setup()
    img=readImage("Cargo Bot:Icon")   -- size 110 x 110
end

function draw()
    background(0)
    fill(255)
    text("Tap screen to split the image",WIDTH/2,HEIGHT-200)
    sprite(img,WIDTH/2,HEIGHT/2)
    if img1~=nil then
        sprite(img1,WIDTH/2-100,HEIGHT/2-100)
        sprite(img2,WIDTH/2+100,HEIGHT/2-100)
        sprite(img3,WIDTH/2-100,HEIGHT/2+100)
        sprite(img4,WIDTH/2+100,HEIGHT/2+100)
    end
end

function touched(t)
    if t.state==BEGAN then
        img1=img:copy(0,0,55,55)
        img2=img:copy(56,0,55,55)
        img3=img:copy(0,56,55,55)
        img4=img:copy(56,56,55,55)
    end
end
3

Here’s another example that splits the image into a lot of pieces.

displayMode(FULLSCREEN)
supportedOrientations(LANDSCAPE_ANY)

function setup()
    img=readImage("Cargo Bot:About Info Panel")
    size=1
    split()
end

function draw()
    background(255, 166, 0, 255)
    v=1
    for x=1,size do
        for y=1,size do
            sprite(tab[v],80+(x-1)*w*1.2+w/2,250+(y-1)*h*1.2+h/2)
            v=v+1
        end
    end
    fill(255)
    text("size  "..size.." x "..size,WIDTH/2,HEIGHT-50)
    text("tap near the top to increase size",WIDTH/2,HEIGHT-80)
    text("tap near the bottom to decrease size",WIDTH/2,HEIGHT-100)
end

function split()
    w=img.width//size
    h=img.height//size
    tab={}
    for x=1,size do
        for y=1,size do
            table.insert(tab,img:copy((x-1)*w,(y-1)*h,w,h))
        end        
    end
end

function touched(t)
    if t.state==BEGAN then
        if t.y>HEIGHT/2 then
            size=size+1
        else
            size=size-1
        end
        if size<1 then
            size=1
        end
        split()
    end
end
4

Thank you very much!