After spending hours finding and collecting URLs of YouTube videos and reading the forum and solving various problems several months ago, I just noticed the image and video for low-bandwidth YouTube videos are pixelated / blocky when viewed in the JW FLV Player on my website, compared with the same low-bandwidth videos on YouTube's site. Is there some setting I can add to fix that, or are all low-bandwidth YouTube images and videos always going to be pixelated in JW FLV Player and relatively sharp on YouTube's site? I hope all the time I spent wasn't for nothing. The player's dimensions are set to a width of 440 and different heights for different playlists (on separate pages), so I wouldn't think that's what's causing it.
The standard, low-bandwidth YouTube video is 320x240. By using a width of 440 you are almost doubling the size of the video. This will cause a degradation in the display quality.
You could use the high-quality YouTube format. I am not sure if most YouTube videos are available in the high-quality format or not; you would have to check your specific videos.
You also have to use a proxy script to get the URL of the high-quality videos because they are not yet available through the YouTube API.
See this thread (post on 17.09.2008) for the YouTube high-quality proxy script:
http://www.jeroenwijering.com/?thread=13017