Do you need to stream JPGs?

Hi all. I am building a slide show that loads external jpgs. I’m trying to build a preloader for this as there is some delay when switching between the images.

the code i have is:

checkLoadPic = function (){
if(imagePic.getBytesLoaded() < imagePic.getBytesTotal()){
    _root.backClip.load_txt.text = Math.floor(imagePic.getBytesLoaded()/imagePic.getBytesTotal()*100) +"%";
}else if(imagePic.getBytesLoaded() == imagePic.getBytesTotal()){
   

it works fine the issue is that it will not trigger the first part that updates the text. I ran a trace of the BytesLoaded and found that it was either 0 or the total amount. So the preloader is skipped and there is nothing happening during the delay. Which leads me to belive jpgs are not streamed. Am I missing something? thanks.