Ars Technica takes a look at the new 1080p content available on the iTunes Store, showing how a “High” compression profile for H.264-encoded content on the iPhone 4S and new iPad and Apple TV are minimizing the increase in file size needed to move from 720p to 1080p. Comparison of 720p (left) and 1080p (right) video quality in iTunes Store content In a survey of several titles now available in 1080p on the iTunes Store, the report found that file sizes generally increased by 15-25% over their respective 720p versions, despite the number of pixels more than doubling to reach the higher standard. The reason that the 1080p versions of the iTunes Store videos can be a good deal better without doubling the file size—or worse—can be found in the tech specs of the new AppleTV and the new iPad
Link:
Improved H.264 Compression Holds Down File Sizes on 1080p iTunes Store Content
