User:JWSchmidt/Blog/21 February 2007

From Wikiversity

Copyleft media files

I added licensing information directly into the audio file for the Wiki Campus Radio test conference call.

is the new version of the file. I guess most people who might work with a GFDL file will be folks who copy the file. If the licensing information is in the audio channel, then it will be passed from listener to listener even under conditions where the file is not simply downloaded from Wikiversity. However, the files I usually make already include discussion of Wikiversity, so it is not clear that a bunch of mumbo-jumbo about copyleft licensing really adds that much for the typical listener.

In the case of more sophisticated folks who might be involved with making derivative works, it is not clear that there is any way to actually control what happens with licensing of derivative works. If a media file originally made by Wikiversity participants ended up getting diced and spliced and incorporated into various derivative works without correct attribution, would anyone really care? If not, then it might make more sense to just include in media files a short and user-friendly infomercial. Maybe the trick would be to convert the legalese into a fun infomercial.

Question about OGG. The original audio file for

that was produced by GarageBand was a 21.7 MB .m4a file. I originally used two different converters and Music Man made the smaller ogg file, that uploaded to Wikiversity as a 12,549 KB file. After adding the licensing information, the new audio file was a minute longer and was exported from GarageBand as a 22.7 MB .m4a file. The Music Man converter produced a 10,437 KB ogg file this time. In both cases, Music Man was using default settings....I'm not even sure if there is a way to control the quality of output. Listening to the new ogg, I suspect it is lower quality than the first version that did not include the licensing information. The QuickTime player indicates that both files are 44.1 kHz, but the older file was 108 kbits/sec while the new one is 87 kbits/sec. In both cases, the original .m4a files were 1441 kbits/sec. I do not see any way to control the bit rate of the output file using the Music Man converter.

I was originally biased towards Music Man over VLC because VLC explicitly says it is not great for file format conversion (they say it is mainly for capturing streams) and the first time I tried it, VLC was slow and made much larger files than Music Man. However, I now see that VLC allows you to select 64, 128, or 192 kbits/sec. The default is 192, which is why it was making larger files than Music Man (87-108 kbits/sec). I tried using VLC to make a 128 kbit/sec ogg, but I ended up with a damaged file that will not play in the QuickTime player but did open in Audacity. I used Audacity to save a new ogg file and it came out at 104 kbits/sec and 12.2 MB. Audacity has a setting for audio export quality; a 0-10 scale with the default in the middle. I tried saving another copy from Audacity at 7/10 on their quality scale and got a file that was 146 kbits/second and 16.5 MB.