OMwiki:Tech

Revision as of 02:08, 5 December 2009 by GChriss (Talk | contribs)


Video capture

Known issues

To-do

  • Rework modcopy to avoid mmap calls on JFFS2 filesystems (e.g., the OLPC-XO). Ticket
  • Document rendering options on other video editors (e.g., XiphQT).

Dreamlist

  • Build open-firmware cameras that record directly to Ogg (2-pass Theora+Vorbis); also include simplified on-camera editing. Elphel has completely-open network cameras, but audio capture and across-the-room zooming might not be implemented.
  • Have cameras set to blur-out individuals broadcasting a 'do not record my voice, person, or both' flag via iPhones, RFID, or colored stickers as mentioned in Yochai Benkler's keynote at OVC 2009.



Editing

Known issues

  • Cinelerra-CV is buggy and somewhat dated. Wait for Lumiera to mature.

To-do

Dreamlist

  • Theora encoding via hardware acceleration (TI C64x+ DSP or an Elphel card?)
  • Find a sensible audio compressor to avoid the time-intensive task of adjusting audio to comfortable listening levels.



Archiving

Known issues

  • FTP is only available for item download and initial upload; item editing is browser-based.

To-do

Dreamlist



Distribution

Known issues

  • Abandon Media RSS ver. 1.5.0 and start on a sensible ver. 1.6. Ver 1.4 is OK.

To-do

  • Figure out a content delivery network and targeted areas.

Dreamlist


OMwiki issues

Known issues

  • Find a way to add style="width:352px;" to embed code in 352×240 streams and fix aspect ratio for 352×240 thumbnails when in category view.
  • Video playback might take ~6 seconds to start for timecodes towards the end of the meeting (pending seeking support in oggz-chop).
  • Google Chrome won't start playback w/ installed version of oggz-chop (affects anything in stream view).
  • Edit MediaWiki:Common.js to download animated gifs only when 'show' is clicked to avoid long page loads.
  • Speaker labels work for annotations but not transcripts.
  • Search works but has a few issues (punctuation stripped, 'play inline' plays audio although video is paused, search-by-date not yet enabled for all videos)

To-do

  • Add a Vorbis-only option on video streams for low-bandwidth connections.
  • Turn on OpenID logins. Need to figure out how to link non-PEAR libraries to non-recompilable PHP or upgrade web hosting.
  • Figure out AJAX auto-complete magic.

Dreamlist

  • Ideas on MetaVid-l (e.g., Identi.ca integration)
  • Replace animated GIFs with low-FPS, enlargeable, jump-to-timecode Theora. Alternatively, use Pad.ma-style mouse-overs (see $(imagePoster).load(function() {...})). The thumbnails should cycle through the meeting in large time chunks when non-mouseover'd, and then display clickable frames according the how far the mouse is from the left edge when mouseover'd. Include ability to pause all animations and step-through lock-step upon mouse clicks.



Video post-processing

Known issues

  • No video post-processing is implemented.

To-do

  • Figure out best options to breakdown tons of video.
  • Fixup and advertise availability of echo.openmeetings.org for compute tasks.

Dreamlist

  • Identify a way to output time ranges generated from multi-speaker audio files, with each time range corresponding to the duration of how long a person spoke for (CMU Sphinx?). Hopefully add speaker identification based on the vocal profile, and maybe even facial recognition and emotional categorization (e.g., laughter).
  • Have individuals appear as virtual avatars in-video (i.e., Second Life-esque), according to user preference.



External apps/reuse

Known issues

To-do

  • ffmpeg/mplayer seems to handle duplicate Theora frames poorly, breaking A/V sync and thus limiting video reuse. Submit bug report.
  • Draft a script to import MetaVidWiki clips from apps that can produce .srt or .cmml captions (e.g., Gnome Subtitles)

Dreamlist


Minor things

  • USB headsets crash spontaneously (error message usb_set_interface failed in Debian Squeeze).



Communicate:



Non-technical development

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