Loading large image

I have se开发者_JS百科en some images loading like, first bad image is load and then slowly its converted to clear image. Which type of images are those? How can i show such effects for large image. So user can see something is happening.

Typically they are interlaced GIF89a format, but you can create interlaced Jpeg and PNG images with Photoshop or ImageMagick.

Netscape browsers also used to support the LOWSRC tag: http://answers.google.com/answers/threadview/id/732321.html

You are talking about jpegs that have been encoded with a progressive/interlaced encoding.

You need to save your jpeg images using this setting in your image manipulation program (GIMP, Photoshop) if you want images to appear progressively.

It has nothing to do with javascript.

I believe you are talking about interlaced PNGs which, while loading, "produce" the effect you're describing. There should be an option in your image editor to save the PNG as interlaced.

edit: I'm not an expert on images, but I think you can use JPEG&GIF also, not just PNG.