search for: bark_noise_hybridmp

Hi, a newbie query about a potential bug in VorbisLib (I tried using bugzilla with no success): My problem is that I encountered a divide by zero exception that I tracked down to bark_noise_hybridmp() in PSY.C. I don't pretend to know what bark_noise_hybridmp() does but there are a few instances of the following in that routine: D = tN * tXX - tX * tX; R = (A + x * B) / D; When I prevented R from being calculated if D == 0 the problem went away and the resultant OGG file could stil...

...nt: Monday, July 6, 2020 4:39 PM To: Ralph Giles <giles at thaumas.net>; vorbis-dev at xiph.org Subject: RE: [Vorbis-dev] can we help with libvorbis release for CVE fixes? Hi Ralph, Thank you so much for not only tracking down the fix for CVE-2018-10393 and adding the extra bounds check to bark_noise_hybridmp(), but also for releasing an official 1.3.7 release with these fixes and other bug fixes! We really appreciate your work on clarifying the CVE fix. Plus with the new release I can upgrade from 1.3.6 to 1.3.7 instead of having to patch piecemeal from the master branch. Please let us know how Ma...

Hello everyone, I recently stumbled upon an issue in the encoder of the v1.0 SDK. At the end of each encoding session a divide by zero (D=0) happens in bark_noise_hybridmp (psy.c:642). This causes a crash on Win9x systems (WinNT seems to handle this fine by using infinite as the result). My encoding code is almost identical to the encoder_example, so I'm reasonably sure that this is not a problem on the calling side. After finding this error I tried the current...

Hi, I'm currently working on a paper describing Ogg Vorbis. It is not finished yet. Mostly the decoder is being described. If you have any comments, please send them to me. See: http://www.turbocat.net/~hselasky/math/vorbis/files/ Then I have a question about the function "bark_noise_hybridmp()" which is used in the encoder. Can someone describe what the function does in detail? From what I can see it performs various kinds of correlation, but I don't see through it. At last I want to point out that at low bit-rates, like 24kBit/sec, Ogg Vorbis has trouble with "S&qu...

...1. How physcoacoustic model is generated . I was reading noise masking . I have understood that FFT of 2048 samples is used for finding tone masking . And MDCT of same samples is used for noise masking . Now while caluculating noise masking , logmdct input is used . And function bark_noise_hybridmp is called . In that function some mathematical computation is done and noise is calculate . ( noise[i] = R - offset ) Can anyone explain me what is the funda behind it . <p>2. NOw about overlap and add . I know very well how overlap add solves the aliasing problem afer IMDCT...

Lancer 20060302 (based on aoTuV 4.51) http://homepage3.nifty.com/blacksword/ Changes: * update to oggenc v2.81 * optimized SSE2 code implementation * bark_noise_hybridmp and seed_curve are inline assembled * modified mdct_forward's SSE optimization * double step bresebham algorithm for render_line, render_line0 implementation

Hi Ralph, Thank you for your reply! For context -- we consider reported CVEs as bugs even if it's in a third-party library we use (such as libvorbis). We first determine if the CVE is something that would impact our customer workflows. In this case because of our use of libvorbis for audio I/O, it does impact our customers so we need to resolve the CVE as soon as possible. In the

...ducible floating point exceptions at lots of sample rate/bit rate combinations. For example, the original encoder_example.c, with just the initialization line changed to vorbis_encode_init(&vi,2,22050,48000,48000,48000); generates a "floating point exception 0xc0000090" in psy.c / bark_noise_hybridmp (line 642). The code reads: D = tN * tXX - tX * tX; R = (A + fi * B) / D; Before the crash, tXX and tX are both 0, thus D == 0. This causes a "divide by zero". As said, it is reproducible every single time. At higher sample rates it works at 48kbps, but crashes at higher bit rat...

Ok, I wasn't able to track down the original steps to reproduce this issue,s but we believe CVE-2018-10393 is a dupiicate of CVE-2017-14160, both fixed by commit 018ca26dece6. Because of the confusion, I added additional bounds checks to the bark_noise_hybridmp function, which make it clear to local analysis that no for bugs in this class are possible. This change is in commit a9eb99a5bd6f. Both of these changes are included in the libvorbis 1.3.7 release, posted today. This upstream release addresses all the CVE issues I'm aware of. Hopefully that a...