educause_2016-tall-2-autosaved
Two 36″x48″ panels (4’x8′ space provided).
ffmpeg tweaks for SS UVMToob ; Bug in server settings
MPEG-DASH streams in FF and Chrome were failing with a No Suitable Media Files error. I thought that maybe this was a lingering key frame interval issue.
While researching I delved ever deeper into ffmpeg and libx264 alchemy. I learned enough to convinve myself that Constant Bit Rare (CBR) files were the root cause of the fuzzy “high definition” transcodes I was getting from visually pristine yet low bit-rate input files. So I switched to Constant Rate Factor (CRF) compression, but maintaining the same max bitrates of 600, 1000, and 3000K.
Old
-vcodec libx264 -vf “scale=min(480,iw):trunc(ow/a/2)*2” -vb 600k -r 30 -force_key_frames ‘expr:gte(t,n_forced*2)’ -pix_fmt yuv420p -c:a aac -b:a 128k -ar 44100 -f mp4
New
-acodec aac -b:a 128k -ac 2 -ar 44100 -af “aresample=first_pts=0” -pix_fmt yuv420p -vsync -1 -sn -vcodec libx264 -r 30 -vf “scale=min(480,iw):trunc(ow/a/2)*2” -threads 0 -maxrate 600k -bufsize 600k -preset faster -tune film -x264opts keyint=60:min-keyint=60:no-scenecut -map_metadata -1 -f mp4 -y
Also, there were some conflicting options set for captions, causing videos with captions to fail when attempting DASH streaming. Fixed. Now 99% HTML5/DASH
Omeka 2.4.1 went live
Title says it all.
USB Thumb Drives, Windows 10, Virtual Box
This was a research and configuration project. Most 303 lab macs should now or soon be properly configured, but it never hurts to check. Procedure sounds something like this…
Log onto MacBook using NetID and password (yes, you can proceed logged in as ctlstaff, but it takes more steps). Launch VirtualBox. Should see something like this:
Scroll down, find and click on USB. Make sure it is enabled for USB3
Insert thumb drive. Eject thumb drive (drag into trash or click eject icon), but do not remove drive from MacBook
Start Windows 10.
Move mouse to top of screen to make VirtualBox menu appears. Select Devices=>USB=>your USB Drive . Done
USB Thumb/Jump drive/Memory Stick and Windows
Figured out the trick to make external USB MSDs (Mass Storage Devices) work with VirtualBox/Windows 10.
Now I just have to teach the trick to all 15 MacBooks Watch this space for updates
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Omeka Update
A development instance of Omeka 2.4.1 (latest) is installed at http://badger.uvm.edu/omeka-2.4.1/ .
Hope is checking it out
It uses a copy of the production database and assets. When Hope gives me the green light, I will copy the dev database over the prod. Hopefully no one would have added any assets or edited an exhibit between now and then
EDUCAUSE poster
Submitted proposal. Proposal accepted Conference late October.
poster session, “Low Threshold Application Streaming Video Server,” was accepted for EDUCAUSE 2016 Annual Conference. Your Poster Session will occur on Thursday, October 27, 2016 from 12:30 PM to 1:30 PM PT
Sustainable Courses database
built cool database for Aaron Witham of sustainability office
https://www.uvm.edu/ctl/apps/sustain/
But he doesn’t work at UVM anymore. Sigh .
Streaming Video bits and bytes
Now witness the power of this fully operational Death st….. oops, I mean streaming server. Quietly went ‘live’ July 1. So far, 350 audio file and 844 video files have been uploaded. Some outstanding issues:
- some submitted pathological files feature video tracks and audio tracks of differing lengths. JWplayer plays to end of shortest (or length of video, hard to tell which since it s invariably the video which is shorter) causing the audio track to get clipped
- some submitted pathological files feature very low bitrates, especially screencasts of PowerPoint, which have solid backgrounds and little motion. When bitrate is below 600 kbps , transcoding yields less than satisfactory results
- multiple back to back submissions try to process in parallel , developing a queuing system to process sequentially
oEmbed with UvmTube
here is some text
And above is the video!
Posted in Projects, Video and Audio
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