background sprite loads stretched

Hello guys, first post and quite a novice on codea/lua coding.
Here’s my problem : I’m planning to make a background sprite to scroll from right to left ( as in most of horizontal 2d shooters ). The sprite scrolls fine, but the image loaded looks blurred as it was stretched.

the image, as saved from photoshop is sized 3372x650 and it doesn’t look any stretched or blurred
( the file can be downloaded from!KQ8SUaSC!Wsx8hGfs1BEOEEm5RxZNcjAPlTJVfk2kYKEmI2BWFaU )
the background class looks like :

bg = class()

function bg:init(x,y)

self.x = x
self.y = y
bg1 = (“documents:bg1”,self.x,self.y,3372,650)

function bg:draw()



and recalled in the main class as below :
function setup()

bg1 = bg(1600,400)

cnt = 0


function draw()

cnt = cnt +1

if (cnt==4) then

1bg.x = 1bg.x - 1




Have you changed the x:y ratio (3372:650<>1600:400) ?

1600,400 is the bg sprite initial position, did I write it wrong? ( as this is not as taken from codea, and currently writing from mac, not ipad :smiley: )