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I'm trying to synthesize a video using a stream of images in JavaScript. The problem is the "video" is either jerky, which was solved by using a buffer of sorts. However now the problem is that images are actually downloaded far faster than they are rendered.
If you have a source of images that changes, like an IP camera you can try the example below. What I have noticed is that, the "video" still updates quite slowly, however while watching a packet sniffer I can see that the image is actually being fully retrieved far faster than it is being rendered.
Here is the example:
<HTML>
<HEAD>
<SCRIPT SRC="http://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js">
</SCRIPT>
<SCRIPT>
function startVideo()
{
//when the buffer image is loaded, put it in the display
$('#image-buffer').load(function()
{
var loadedImage = $(this).attr('src');
$('#image-displayed').attr('src', loadedImage);
$(this).attr('src',
'http://path.to/image.jpg?nocache=' + Math.random());
});
$('#image-buffer').attr('src',
'http://path.to/image.jpg?nocache=' + Math.random());
}
function stopVideo()
{
$('#image-buffer').unbind('load');
$('#image-buffer').attr('src', '');
$('#image-displayed').attr('src', '');
}
</SCRIPT>
</HEAD>
<BODY>
<BUTTON ONCLICK="startVideo();">Start Video</BUTTON><BR/>
<BUTTON ONCLICK="stopVideo();">Stop Video</BUTTON><BR/>
<IMG ID="image-displayed"/>
<IMG ID="image-buffer" STYLE="visibility: hidden;"/>
</BODY>
</HTML>