A forum post to Chinese-language site weiphone.com indicates that the iPhone 3GS is capable of playing back both 720p and 1080p video encoded in H.264 through the built-in video player, suggesting that Apple is currently placing arbitrary limits on the device, either to preserve battery life or keep its functionality more consistent with that of prior iPhone OS devices. Using the free document storage and viewing application FileAid, forum member fridtear was able to circumvent Apple's video restrictions, smoothly playing back files up to 30 Mbps in 1980x1080 resolution via the iPhone 3GS' built-in video player.
While such high-resolution video is obviously not necessary for the iPhone itself, which offers only a 480 x 320 pixel display, many users are interested in outputting video for display on external monitors, and the iPhone 3GS is by default limited by Apple in that regard to the same 640 x 480 resolution, 1.5 Mbps standard used by older iPhone models. Of course, the large file sizes involved in high-definition, high bitrate video would restrict videos to relatively short clips given current iPhone storage capacities. The tests also did not address the effect of such video playback on heat or battery life under extended usage.Rumors surfacing in late April hinted at high-definition capabilities for what turned out to be the iPhone 3GS, but while this latest report indicates that the hardware may be capable of it to at least some extent, Apple has elected not to enable it at this time.
