Linux-audio-dev

linux-audio-dev@lists.linuxaudio.org

7516 discussions

Re: [linux-audio-dev] BruteFIR + jack = crackling noise?

by John Lazzaro

> we don't care about non-power-of-two periods, i think. however, i do > consider periods defined in units of times and not frames to be broken > hardware design. it forces inefficiencies into the software that are > totally unnecessary. For what its worth, the SAOL standard has to deal with this problem too, since the user gets to specify an integer k-rate and an integer a-rate. Eric went for this solution: 5.8.5.2.2 krate parameter <global parameter> -> krate <int>; The krate global parameter specifies the control rate of the orchestra. [...] The krate parameter shall be an integer value between 1 and the sampling rate inclusive, specifying the control rate in Hz. [...] If the control rate as determined by the previous paragraph is not an even divisor of the sampling rate, then the control rate is the next larger integer that does evenly divide the sampling rate. The control period of the orchestra is the number of samples, or amount of time represented by these samples, in one control cycle. --- This has been controversial, since it limits the ability to use SAOL to emulate existing coding standards that have non-integer relationships betweens frames and the sample rate. The win has been decoder implementation simplicity. ------------------------------------------------------------------------- John Lazzaro -- Research Specialist -- CS Division -- EECS -- UC Berkeley lazzaro [at] cs [dot] berkeley [dot] edu www.cs.berkeley.edu/~lazzaro -------------------------------------------------------------------------

22 years, 8 months

[linux-audio-dev] [ANNOUNCE] tapiir-0.7.0

by Maarten de Boer

Hello, I just released a new version of tapiir. Tapiir now supports jack. Tapiir can be found at http://www.iua/~mdeboer/projects/tapiir/ Tapiir is a simple and flexible audio effects processor, inspired on the classical magnetic tape delay systems used since the early days of electro-acoustic music composition. It provides a graphical user interface consisting of six delay lines, or "taps", which can introduce an almost arbitrarily big or small delay to their inputs and can be feed back to each other. A wide set of effects can be easily achieved by properly configuring and connecting the delay lines: complex echo patterns, resonances, filtering, etc. Delays, interconnections and gains can all be controlled in real time. Maarten

22 years, 8 months

[linux-audio-dev] BruteFIR + jack = crackling noise?

by Werner Johansson

reposting to the list, my email client had some hick-ups.. Paul Davis <paul(a)linuxaudiosystems.com> wrote: > if you mean at JACK's level, then it prints out information about > xruns. i think you mean something else, but i'm not sure what. OK, but jackd is accessing a DMA buffer - where would that be located for USB devices which doesn't do any real DMA? (OK, maybe that's something for ALSA to figure out) The debugging I was thinking about would be something more fine-grained than just xruns (as I'm not getting any xruns (well, if I choose a period size of 64 I'm getting lots of them). I'm not really sure what to monitor either, just thinking out loud here - it might be interesting to find out where the actual playback and recording pointers are pointing when accessing the buffer to find out whether something is out of sync (it kind of sounds like that, that the beginning of the buffer gets overwritten with new data, or that the end of the buffer somehow isn't completely written when jackd grabs it). Not sure whether jackd can actually see that though (?). The two parts of the buffer (when using two periods) is laid out consecutively in memory, right? One possible explanation might be that jackd gets called a bit to early/late when the audio device/driver is switching buffers, but that would be kind of hard to actually see for jackd as a client to ALSA? (I recognize the audio artifacts from the good old days of DOS demo coding of SoundBlaster DMA, at one point where I had screwed up the logic, writing in the "live" buffer, then the beginning of every period was anything but clean...) This isn't CPU related, there's plenty of CPU time left, and it's occuring all the time, just curious where to start debugging (it seems like it's a jackd problem because aplay works fine, but then again, I guess that aplay doesn't mmap the buffer).. /WernerJ

22 years, 8 months

[linux-audio-dev] ANNOUNCE SonaSound

by Niklas Werner

Hi LADers! I released a realtime Music-visualization-program (my master's thesis) on http://sonasound.sf.net. It's probably more of academic use at the moment. Licensed under GPL. Maybe there is some interest. Features are: - Waveform-Display - short-time-spectrum - sonogram - spectrum-generation switchable between lpc and fft - Major kinds of windowing functions choosable - Different kinds of windowing functions are directly comparable via live-switching - Overlap of 50% can be switched on and off without stopping - Buffer-Size and FFT-Size freely adjustable - All Displays work from soundfile while playing or direct live-input from soundcard - Comparison of different spectrum-generation-methods via multiple instances fo SonaSound possible Libraries needed: - fftw (www.fftw.org) - glib >= 1.2 - gtk >= 1.2 - gtkglarea - GL - GLU - portaudio (www.portaudio.com) (Yes, I know, switching to JACK might help) - sndfile >= 1.0 There are many features I would like to add and a few not-so-good-features I'd like to clean up. Have fun* Niklas

22 years, 8 months

[linux-audio-dev] ZynAddSubFX 1.0.9 relased

by Nasca Paul

Hi. I relased ZynAddSubFX 1.0.9 (a very poerfull software synthesizer for Linux). News: - added keylimit to Part - you can use multiple filter stges in order to make very steep filter rolloffs (eg. 48 dB/octave) - ADsynth - added noise mode and you can make fixed frequencies; added the "Punch" parameter - added an external program "Controller" which enables you to use the mouse for MIDI controllers - other improvements and bugfixes See more at http://zynaddsubfx.sourceforge.net Paul. __________________________________________________ Do you Yahoo!? Yahoo! Tax Center - forms, calculators, tips, more http://taxes.yahoo.com/

22 years, 8 months

[linux-audio-dev] amble (was: blockless processing)

by Simon Jenkins

Here's another take on that paste-it-together-out-of-C-code "blockless processing" idea that was discussed a few months back. Its incomplete and experimental, and I'm not sure how much further its worth pursuing it (I'll keep it going for a while longer I think) but its pretty interesting if you like this sort of thing: http://www.sbibble.pwp.blueyonder.co.uk/amble/amble-0.1.1.tar.gz Some (not all) of the demos require libsndfile and its headers. Simon Jenkins (Bristol, UK)

22 years, 8 months

[linux-audio-dev] SuperCollider

by Miha Tomsic

Hello LADies and LADdies! What is new on the SuperCollider front? I've seen there are some new files up on the page and will try to compile them later today. Take care, Miha...

22 years, 8 months

[linux-audio-dev] crusoe ll problems

by jfm3

I'm trying to run a low latency kernel and audio applications on a crusoe processor laptop. Yes, I'm crazy. I have patched a 2.4.20 kernel with the low latency, preemption, and variable hz patches, as well as a modification to the alim15x3 DMA code and an extra entry in the "unusual USB devices" list. I'm running recent CVS checkouts of ALSA from Planet CCRMA. The kernel works well, and the low latency patches really make the system more responsive even under load. However, when I run latencytest0.42/do_test blah blah, the system hangs while playing the sound. It does not even display the xperf window. After a very long time, Control-C stops the process. When I run jack -R (jack 0.55) and freqtweak, freqtweak claims it gets "shut down" by jack the first time I try to start it. The second time I try to start it, it connects to jack and plays for a few seconds, but then audio stops and the system hangs. I need to use sysrq or a power cycle to restart. I can send pretty good beer, the alim15x3 patch, and any other clues to anyone who can help me with this. -- (jfm3 2838 BCBA 93BA 3058 ED95 A42C 37DB 66D1 B43C 9FD0)

22 years, 8 months

[linux-audio-dev] can somebody tell me how to create a .wav file from the sound buffer or gsm?

by leo zhu

I have already got the sound data from sound card into the buffer, and I've also finished it to encode the data to gsm and send to another server. Right now I need to store the sound data to some .wav file in the server. How can I do it, ether from memory buffer or gsm? Are there any API to do it? Thanks. __________________________________________________ Do you Yahoo!? Yahoo! Tax Center - forms, calculators, tips, more http://taxes.yahoo.com/

22 years, 8 months

[linux-audio-dev] [announce]

by ljp

Hello, This is to announce a web forum dedicated to Linux and recording. http://www.recording.org/cgi-local/ubb/ultimatebb.cgi Come and join the fun!

22 years, 8 months

Jump to page:

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

Linux-audio-dev