You Tube announced last year (November) that they started to test higher quality videos. There are now a few samples of videos in YouTube that are uploaded and can be seen in a higher resolution. The regular version of YouTube videos have a 320×240 resolution and can be seen now with an upgrade of 448×336. The audio encoding is also said to have improved from the normal 22050Hz to 44100Hz.

To watch the videos in a higher resolution, all you have to do is add &fmt=6 to the end of the video URL (so the URL will have to look like this (http://www.youtube.com/watch?v=wnVJZkDuVBM&fmt=6 ). You will notice a slight improvement in the resolution. This upgrade doesn't come without a price. The improvement in resolution will result to a slower download due to an increase in the size of the re-encoded video. To get a much higher resolution of 480×360, just add &fmt=18 at the end or the YouTube video URL. By doing this, there is a chance of getting an MP4-encoded version which also comes in a larger size. This trick does not work on all videos. It has been reported that newer videos can only be viewed in high resolution.

If ever you don't want to go to all the trouble of placing the code on every video you visit in order to view it in improved resolution, there is another way of doing this with the use of Greasemonkey Firefox extension. If you do not have Greasemonkey installed in your Firefox, you can download it here. Then, install the YouTube HD script than can be found here.  By doing this, you can view all the YouTube videos that have higher resolution automatically. However, if you feel that it is slowing down your streaming or the videos stopped loading, you can always disable the script in Greasemonkey by pressing right click on the monkey head at the bottom of your Firefox browser and unchecking the YouTube HD tag.

Note: In order for all of this to work, you need to have the latest version of Flash Player installed in your system.