On the next-generation iPad launch event, Apple has announced that they are rolling out the support for 1080p Video Content on iTunes, and with the new iOS 5.1 the new-generation devices will be qualified of playing real 1080p content on their core without any limitation from the Apple. Apple has made this announcement with the introduction of new Apple TV that is eventually capable of playing 1080p content with the older gen-A5 dual-core processor, exactly the same processor your old Apple TV had from months. However, it is reported by the Ars Technica that Apple has started pushing a new model of H.264 compression for the 1080p Video content on the iTunes and providing a “High” compression profile of video for the iPhone 4S, and the new iPad, and Apple TV.
It is also reported that the new 1080p content from the iTunes generally carries the least increase in their file size while the move from 720p to 1080p. In a survey from the Arc Technica, it is discovered that several titles on the iTunes with 1080p video content are generally increased by 15-25% over their old 720p video compression version, and the pixels of the video is indeed doubled from their current resolution without any massive increment in their file size.
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. The AppleTV now supports H.264 compression for 1920×1080 resolution video at 30 frames per second using High or Main Profile up to level 4.0, the iPad and the iPhone 4S the same up to level 4.1. The profile indicates what kind of decompression algorithms the H.264 decoder has on board—the “High” profile obviously has some tricks up its sleeve that the “Main” or “Baseline” profiles known to previous devices don’t support. The level value indicates how many blocks or bits per second a device can handle.
The report also offers a comparison of video quality between the 720p and 1080p formats on the iTunes Store, noting that the increase in image quality for 1080p content is minor in many cases, but more significant in brighter scenes.