View source for Video Player

From Openmoko

Jump to: navigation, search

You do not have permission to edit this page, for the following reasons:

  • The action you have requested is limited to users in the group: Administrators.
  • You must confirm your email address before editing pages. Please set and validate your email address through your user preferences.

You can view and copy the source of this page:

Templates used on this page:

Return to Video Player.

Retrieved from "http://openmoko.org/wiki/Video_Player"
Personal tools

Not a proper 'app' page, just an overview of my understanding. --Speedevil 17:39, 16 February 2007 (CET)

Video is problematic.

On the minus side.

  • The CPU is certainly not fast enough to decode 480*640 video.
  • The display is portrait, which means that an additional rotation step is needed for most landscape video, adding to CPU usage.
  • Downloading an arbitrary video, and playing it without transcoding it, then playing it later will not be possible.

However.

On the positive side.

  • The LCD can be switched to a 240*320 stretch mode, which is much less taxing.
  • Re-encoding video to rotate it, and scale to 320*240, and encoding with a low CPU use codec such as MPEG-1 may well make half-screen doubled videos playable at 25fps.
  • If not, then it almost certainly will be possible at 12fps.
  • Playing most very small - postage stamp - videos as are sent by many phones should be possible.
  • 1G of storage should give several hours of mpeg4 video, as the quality can be reduced somewhat without being visible on the screen.

From a conversation with XorA, in #openmoko.

400kbps mpeg4 works on a 200Mhz neo (without sound) on prerotated 240*320 ffmpeg codec videos, at 25fps, using stock mplayer.

With sound, this drops to 18fps.

There are optimisations for mplayer that look promising to get 25fps with sound.