The VideoLAN Forums

I put some videos on my iphone to VLC player,
when i try to play the video, it says your device maybe to slow.
so when i try anyways, it is choppy and wont play....
anyone know y its not working correctly, or do i need to do something to make it work
please help

Here are some of the official limitations of the iPhone:

For H.264 playback:
Profile: Main (default in x264 is High)
Level: 3.1 for the iPhone 4, Level 3 for the iPhone 3
CABAC: Yes
Max Resolution: 1280*720p (iPhone 4) or 640*480p (iPhone 3)
Max framerate: 30 FPS
Max bitrate: 2.5 Mbps (iPhone 4) or 1.5 Mbps (iPhone 3)
VBV Buffer Size: 10 000
VBV Max Rate: 10 000

In fact even the iPhone 3 can handle H.264 High Profile @ Level 4.1 and also VC-1 Advanced Profile, not to mention the good old MPEG-4 ASP, because it's using the Samsung S5PC100 chip. But iTunes is the blocker if your video exceeds the specs mentionned above so you may want to use an alternative third party software.

For AAC playback:
Max bitrate: 160 Kbps
Max samplerate: 48 kHz
Max channels: 2 (stereo)

So pretty much covert file down to lower quality for iPhone 4 play back?
I know vlc can do this. What is the best format that will play hd videos correctly?

Also where is iTunes copying the file to?

I'm having the exact same problem, and the funny thing is that it's worked well up until now!
I've probably watched 20 Grey's Anatomy episodes with my iPhone trough dropbox onto vlc. It would lag a little bit, but if I paused for 10 sec the whole episode would play fine afterwards. But now all of a sudden "the device seems to be too slow" to play the same file. Makes no sense at all to me :/ I dunno how to convert and the reason why I use dropbox to adf the files in the first place was because this was supposed to be Quick and easy >< frustrating!!

on my iphone 4 app plays SD (avi) videos fine, but HD (mkv) videos come up with message 'Your phone may be too slow...' and doesn't play.

on my iphone 4 app plays SD (avi) videos fine, but HD (mkv) videos come up with message 'Your phone may be too slow...' and doesn't play.

Normal.