i Tunes itself does not support playback of most HD videos yet, and common HD video formats such as AVCHD (mts and m2ts), TOD, MOD, HD MKV, TS etc. However, i Tunes allows you to import videos such as MOV, M4V and MP4 with no restrictions on the video resolution.
Therefore, you can take advantage of this, convert HD to high resolution MOV, M4V or MP4 videos, and import the converted HD to i Tunes.
To do this, i Funia HD Video Converter is an ideal tool to choose.
Apple now offers 1080P HD video rentals and purchases in i Tunes, but it’s important to note that the i Tunes Store has not seen a wholesale updating of HD content into 1080p.
Much like the SD-HD divide, many shows continue to be available only in the older 720p resolutions, while others have been updated to add the higher-resolution 1080p format.
Here’s what you need to know about getting 1080p content at i Tunes.
Most people can’t tell the difference between a 720p and 1080p video when shown on a distant television, but with the new i Pad’s Retina display, the 1080p capable Apple TV 3, and whatever other upcoming high definition displays come from Apple, you’ll almost certainly notice the improved clarity and resolution fo 1080p.
Just be aware that 1080p content takes up much more disk space, so you may want to keep 720p as the default if you are concerned with available storage.
Ars Technica took a look at various file sizes and found that going from 720P to 1080P resulted in a file size increase of 21-25%.
This is because Apple uses better compression, to keep file sizes small without degrading quality.
In the sample above, you can see the difference between 720P and 1080P, which is more noticeable on some shows and movies than on others.
Since not all Apple devices can play 1080p content yet, Apple gives users a choice of which kind of HD content they’d prefer to download.