How To Maximize Videos for Viewing on Mobile Devices

I wrote an article on how to maximize video viewing for the iPod Touch. (Quality vs File Size)

I revised the article since the concept is applicable to any mobile device - cell phone, other mp3 players.

This process reduces the resolution of your video so that it it has the smallest possible file size without sacrificing quality.


Anyway. Lets start.

Take note of the resolution of your device - this is very important. When you are converting video files for viewing on a mobile device, ensure that the resolution of the resulting video is less than the device's screen resolution. Higher resolutions will most likely still be playable, but you wont notice too much of a difference since the device wont be able to display the additional pixels anyway - it'll just fit everything in its screen. No use cramming up 720 pixels of video on a 480 pixel screen right? Its actually worse if the resolution is too high as it takes more processing power (generates more heat and shortens battery life) to play. But then again, if you choose a resolution that is too low, you are giving up quality too much.

Example: Say your device has a screen resolution of 480 x 320 (this is just an example, your mobile device almost certainly have a diferfent resolution). But you want to put in a video whose resolution is 720 x 540. (say you ripped from a DVD or form an online video you downloaded)

Again, the height and the width of the video needs to be less than or equal to the mobile device's resolution. We need to scale the video to a resolution closest to 480 x 320.

But do not just directly convert to 480 x 320. When scaling down, the proportion of the width to the height needs to be retained. Depending on the original resolution, it can create an undesirable stretching effect if you just directly convert to 480 x 320.



To properly scale down, just divide the height and width of the video by the same number so that the width is less than or equal to 480 and the height is less than or equal to 320.

Example:

Divide the height and width by 2.

720 / 2 = 360. This is the width

540 / 2 = 270. This is the height.

Resulting resolution will be 360 x 270. Although this will save a lot of disk space, you will not be able to maximize the iPod's screen.

Lets use 1.5

720 / 1.5 = 480

540 / 1.5 = 360

Though the width (480) will fit perfectly on the iPod's screen, the height (360) is too tall. It will work, but this will not get us the best file size to quality efficiency.

Lets use 1.7

720 / 1.7 = approx 424

540 / 1.7 = approx 318

Resolution 424 x 318 would be our ideal choice. Its not too tall nor too wide for the mobile device's screen. But it still uses up the screen to its full potential based on the original file's resolution.