OMwiki:Tech
[edit] Recording devices
[edit] Known issues
- Fixup non-compliment DV hardware + firewire-core Example ticket
[edit] Possibly fixable
- Rework modcopy to avoid mmap calls on JFFS2 filesystems (e.g., the OLPC-XO). Ticket
- Investigate audio ground loops and prevention techniques
[edit] Dreamlist
- Find a portable camera or device that records footage from two audio sources (e.g., XRL mic + ambient mic) time-synchronized to a video track.
- Migrate to open-firmware cameras that record directly to Ogg; also include simplified on-camera editing. Elphel has completely-open network cameras supported by the Apertus community.
- Auto-balancing, wireless, golfball-sized mics that are mutable by the camera. Best for when push-to-talk mics are not available.
- 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.
[edit] Editing
[edit] Known issues
- Cinelerra-CV is buggy and somewhat dated. Wait for Lumiera to mature.
[edit] Possibly fixable
- Add YUV4MPEG support in Blender to enable direct output to ffmpeg2theora (email thread), building upon File:Henningsen 7oct2009 blender-svn.tar.bz2 Also build-in yuv4ogg suFigure out a pport as per xiphmont's lead.
- Find a plugin/filter that synchronizes audio captured from a secondary source; slight a/v sync drifts accumulate over time, making 2nd-track audio recombination difficult.
- Document export options to accommodate a wider range of video editors; firefogg is an option.
[edit] 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.
[edit] Archiving
[edit] Known issues
- FTP on the Internet Archive is only available for item download and initial upload; item editing is browser-based.
- Video playback on Internet Archive description pages (inc. <video> fallback) requires the presence of a Flash-based derived file. These derived files are manually deleted post-upload.
- OpenMeetings.org is not crawled by the Wayback Machine.
[edit] To-do
- Retool download_from_archive_org.php to work with different source videos and meta tags from the Internet Archive, using this wikipage as a working draft.
[edit] Dreamlist
- Implement template support on the Internet Archive description pages.
- Secure logins + strong item deletion-prevention.
[edit] Distribution
[edit] Known issues
- Forgo Media RSS ver. 1.5.0 and start on a sensible ver. 1.6. Ver 1.4 is OK.
[edit] To-do
- Implement content delivery network, which will involve site migration.
[edit] Dreamlist
[edit] OMwiki issues
[edit] 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. - Google Chrome has buggy Theora support.
- 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)
- White-on-black site design works well for focusing attention on video streams (right?), but fares poorly for text-heavy pages. Implement an automatic "turn down the lights" feature when video is in a 'play' state.
[edit] 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.
- Fix Google search listing.
- Start up project blogging, @openmeetings.org email addresses, and listing of similar projects.
[edit] 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.
[edit] Video post-processing
[edit] Known issues
- No video post-processing is implemented.
[edit] To-do
- Figure out best options to breakdown tons of video.
- Fixup and advertise availability of echo.openmeetings.org for compute tasks.
- Machine synchronization of known-good transcripts to video (i.e., match individual words to the exact timecode spoken).
[edit] 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 or Avatar-esque), according to user preference.
[edit] External apps/reuse
[edit] Known issues
- Wait for mwEmbed's libSequencer to mature; squash bugs.
[edit] 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)
- Figure out a easy way to integrate playback with blog platforms, including various commenting systems (i.e., plugins). Known hacks
[edit] Dreamlist
[edit] Minor things
- USB headsets crash spontaneously (error message
usb_set_interface failed
in Debian Squeeze).
[edit] Communicate:
- Join and post to MetaVid-l
- Join #metavid and #mediawiki. No IRC? Click here to join via a webclient.
- Have your work recognized on Sunlight Labs: Projects by contributing code.
[edit] Non-technical development
- Please see OMwiki:Volunteer