search for: ehmer

There's a new module in CVS called 'masktest'. I spent the last few weeks writing this program. It can measure masking based on input from people. We need it to obtain better masking curves than we have right now (from Ehmer...). It's not finished yet, but you can get a feeling of what it's supposed to do. It will measure the masking between tone and tone, noise /tone, tone/noise and noise noise. When it's ready it's supposed to be downloaded by a lot of people who then take this test and send us a...

...sk (chief Vorbis Evangelist among other things) said, "Hey! We need to demo to the world on the 4th of April!" Hooo boy. Time to suck it up and bang it out. The Vorbis libs are not a problem. I'm in process of checking in my new psychoacoustics (they're real pretty!) based on Ehmer's and Fielder's masking papers and making last minute updates to the libs and lib APIs. This will be done in time, no sweat. Libvorbis/vorbisfile are the least of my worries. Most of the work remaining to be done is in the details. I need help, and I need alot of it in the next week. He...

...papers on the web, I distilled out the raw masking curves. I also added in a few of the raw masking curves as published in "Paramaetric Bit Allocation in a Perceptual Audio Coder"; this paper only mentions in passing that Dolby distilled their masking data for AC-3 research from both the Ehmer papers I already mentioned and later research done by Loius Fielder. I have the Fielder papers on order... hopefully they'll arrive next week. In http://www.xiph.org/ogg/paper I've placed an .xcf file containing the graphs as overlays (this is a Gimp native file). Use the 'Layers and...

Hi, I need a psychoacoustics model for some experiments and would like to use the one included in vorbis. Is there any documentation about how to use it? Looks like the relevent code is in psy.c, but I can't go further. Also I would like to know whether I can be of any help in vorbis. I have some knowledge in speech coding (I doing my master at the University of Sherbrooke's speech

Hi! Can someone say to me, how the following values are assigned? I assume that it concerns different frequencies, but which? Excerpt out: ?masking.h? .. static float tonemasks[P_BANDS][6][EHMER_MAX]={ /* 62.5 Hz */ {{ -60, -60, -60, -60, -60, -60, -60, -60, -60, -60, -60, -60, -62, -62, -65, -73, -69, -68, -68, -67, -70, -70, -72, -74, -75, -79, -79, -80, -83, -88, -93, -100, -110, -999, -999, -999, -999, -999, -999, -999,...

I tested Vorbis encoder - beta3 version, and here are my thoughts: - In comparison to beta2, subtle high-frequency artifacts seem to be gone (though they were small in beta2). Good job there! :-) - Velvet.wav also sounds better, but transparent quality is reached at -b256+. - Horn.wav still sounds very sucky, mode -b256 gives ~100kbps (this is understandable because in this sample practically