A key draw of the iPhone as a portable video player (PVP) is the fact that its complementing software, iTunes, offers a cheap, easy, and legal way to get content that will play on the device. But what if you already own the video files you’d like to watch, but they’re in any variety of formats that aren’t natively supported by the iPhone? iTunes has a built-in Video Converter, but then you’d be limited to the file types that QuickTime supports. You may need a different Video Converter for Mac
The iPhone 4, the iPad, and the latest versions of the iPod touch all support H.264 main profile level 3.1. What that means is that you can play HD video with a resolution of up to 1280×720 and a framerate of 30 frames per second. iPad Video Converter That’s a significant step up from the baseline profile level 3.0 (720x480x30 or 720x576x25) that the older iPhones and iPod touches support, and even an improvement over the older Apple TV, which could only play 1280×720 video at 24 frames per second or less. The main profile rather than baseline profile means that it’s possible to use more effective compression.
Another way to accomplish the same thing is to import the files in iTunes and choose “Create iPod or iPhone Version” or “Create iPad or AppleTV Version” from the Advanced menu—again, both are compatible with the iPhone 4. This has the advantage that you can batch convert a set of files. But be warned: iTunes doesn’t handle multithreading very well and becomes much less responsive during the conversion process.