Hello Jim, Awsome test, a very important tool for designing correction. To me it indicates that we don't have to be too afraid of error rates in the % range, 1/48 works for most bits with 100% intelligibility, while some few bits create an awful listening experience and need to be correctable.
Considering that error rate will probably vary over time ( aka. fluttering ) single corrupted frames (with low error rates) interleaved with good frames will have a good chance of propagating acceptable / enjoyable audio. 73 de SM6FBD On 26/10/12 09:58, Jimmy Carter wrote: > Hello again, > > I went ahead and tried to make it a little easier for others to help > with the subjective measurements. > > A small write-up can be found at http://kg4sgp.com/codec2-bit-study.html > . This page has links to audio with corresponding bit corruptions. From > the listening I've done there is definitely a difference in the > sensitivity of the different bit types. > > Please excuse the simple site. As you can probably tell it's not a > priority of mine. > > KG4SGP - Jim > > On 10/26/2012 01:03 AM, Jimmy Carter wrote: >> Hi all, >> >> I'm new to the list, but am interested in helping out with codec2 and >> this seemed like the perfect thing to start with. >> >> I started writing a program to cause bit errors at specified locations >> in the frames in order to judge their importance. Got it working just >> a bit ago and decided I would share it here. >> >> The C code can be found at: >> http://www.kg4sgp.com/code/errbit.c >> >> Its not the cleanest/prettiest code, but it works :) . >> >> It can be piped and I have used it in-line with some of the examples. >> If everyone is interested I would be happy to take some of the sample >> audio files and encode them with bit errors at different positions >> across the different bit rates. I could write that up and post it to >> my site, or where ever you guys would like. >> >> Already it can be seen that certain bits are very important! >> >> Looking forward to your replies! >> >> KG4SGP - Jim >> >> On 10/24/2012 06:17 PM, David Rowe wrote: >>> Hello, >>> >>>>> Given what Jean-Marc wrote about the first VQ index, it probably rates >>>>> higher than energy. >>>> If David and/or Steve can confirm this; it makes sence to incorperate >>>> this in the search for a good interleaver. >>> It's best to test the relative sensitivity of the different codec >>> parameters. So set up the FEC/interleaving so that we can evaluate >>> different schemes, apply say 1-5% random errors and listen to the >>> results for a few test sentences. >>> >>> The index assignment Jean-Marc suggested may provide as much improvement >>> as FEC. >>> >>> Cheers, >>> >>> David >>> >>> >>> >>> ------------------------------------------------------------------------------ >>> >>> Everyone hates slow websites. So do we. >>> Make your web apps faster with AppDynamics >>> Download AppDynamics Lite for free today: >>> http://p.sf.net/sfu/appdyn_sfd2d_oct >>> _______________________________________________ >>> Freetel-codec2 mailing list >>> [email protected] >>> https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > > ------------------------------------------------------------------------------ > Everyone hates slow websites. So do we. > Make your web apps faster with AppDynamics > Download AppDynamics Lite for free today: > http://p.sf.net/sfu/appdyn_sfd2d_oct > _______________________________________________ > Freetel-codec2 mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 ------------------------------------------------------------------------------ The Windows 8 Center In partnership with Sourceforge Your idea - your app - 30 days. Get started! http://windows8center.sourceforge.net/ what-html-developers-need-to-know-about-coding-windows-8-metro-style-apps/ _______________________________________________ Freetel-codec2 mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/freetel-codec2
