TIM and I had a quick chat yesterday after it turned out that we had oversampled 38 shows/episodes, basically saving at a sample rate far greater than what we had recorded. This becomes especially problematic because audio files are serves by a cache server that drops the connection after 10 minutes, which means that timeouts will affect downloaders on a low-bandwidth connection. Some listeners reported this to us last year, but it wasn't until yesterday that we thought about shrinking file sizes. The idea came from a listener. On an important and technical note, this listener asked whether feasible to "make the files much smaller (monophonic with a slower sample rate and lower resolution)." I then spent over an hour experimenting with Audacity and ffmpeg
. I ran a series of tests where parameters in the encoders are changed and I then listened to the results. The VoIP recording we do is at 16KHz, compared to the far greater frequency which we used to encode this in (huge waste of space for no gain in quality). Eventually I found that even without using the command line, e.g. ffmpeg -ab 16k -ar 11025
, I could still rely on Audacity to handle both .mp3
and .ogg
extensions to produce files about a quarter of the size they used to be. The only drawback of that is that when we have music tracks (of higher sampling/resolution) they obviously degrade in quality. Since the vast majority of the recorded tracks will always be talk, that ought to be worth the compromise and smaller files would also make storage and bandwidth less of an issue (caching resolves only the latter, to a degree).
gtk-recordmydesktop
can be used to show Web sites and other things while the show is running. ⬆
Comments
satipera
2011-04-13 09:32:03
Dr. Roy Schestowitz
2011-04-13 13:47:40
Needs Sunlight
2011-04-13 09:33:15
twitter
2011-04-13 13:03:01
Dr. Roy Schestowitz
2011-04-13 13:46:37
twitter
2011-04-13 23:50:46
Are the free software sip clients up to this yet? Skype can do the multi video chat thing I think, but it is a pay service and I don't think Skype works with Lenny or on anything but x86.
Dr. Roy Schestowitz
2011-04-13 13:46:01
kozmcrae
2011-04-13 13:50:11
No, seriously. It's good to hear about the bandwidth. I would also like to add my two cents about the sound. First, the volumes between the three of you are uneven. I used the compressor in Audacious and was able to even it out somewhat. But there's one aspect of the sound I can't seem to control. It's the relative frequencies. Tim comes through the best, smooth and well rounded. Then Gordon's, but Roy, you must burdened with a poor quality microphone because your voice sounds like it's coming through on one band in the midrange of an equalizer. There's no way I can fatten it up to sound more like Tim's voice. I spent the better part of my life playing music and working with sound, maybe that's why I'm sensitive to it. Unfortunately I no nothing about working with sound over the Internet so I have no advice, just some critiques.
Dr. Roy Schestowitz
2011-04-13 14:20:24