I noticed how some videos on YouTube are full width, meaning that the video fills the whole video player but some videos including mine are very centered and leave dark spaces at the side, like the player is to big for the video. Is there a way to make the video bigger to fill the whole player? +rep for any hep. Thanks!
They have different aspect ratios (proportions). Some are 4:3 and others 16:9. Examples: 640x360 is 16:9 and 480x360 is 4:3. So 16:9 will be filling all the space. So you have to create them with corresponding proportions - 640x360, 720x576, 1280x720, and so on...
There are many ways to make this happen, While watching the video at youtube, you can make plugins into the firefox and then make the videos stretch to full page and download them. The second is that you can download the video as FLV format and then convert it using a converting software and in that you can mention the resolution you want to be in the converted video. Hope this helps...