Linux-audio-dev

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7440 discussions

[linux-audio-dev] MIDI Clock and ALSA seq

by Steve Harris

Hi all, I'm trying to hack up a quick app that sends MIDI clock pulses in sync with a ringbuffer playback. I've got it reading MIDI (thanks to Matthias' great exmaple code), but I cant figure out how to send MIDI clock pulses explicitly. The ALSA seq interface lets me set it up to go automatically, but I want to send a clock pulse every 1/24th of the buffer, so the sync is correct. I dont think I can use raw MIDI because I need the ALSA seq for other apps, on the same MIDI port. - Steve PS I know there are several apps that can, or will be able to do this, but I need it to work by saturday. Its disposable code.

21 years, 7 months

[linux-audio-dev] Re: Steve Harris' C++ v C benchmark

by Robert Jonsson

Hi, > >>> I think that for applications like audio processing where speed is one of >>> the main goals benchmarking is extremely important. Personally I would >>> love to see more people do it properly and publish their results like I >>> did here: > > > Agreed. If someone that knows c, c++ and objective c were to write up an > audio focused benchmark that would be great. I've not realy used GObject, > but I guess it should include that too. Okay, this isn't even remotely audio focused, but nevertheless very entertaining reading. - The great computer language shootout - http://www.bagley.org/~doug/shootout/ /Robert

21 years, 7 months

[linux-audio-dev] Steve Harris' C++ v C benchmark

by Erik de Castro Lopo

Hi all, A couple of days ago Steve Harris posted results from a quick benchmark on on the jackit-devel mailing list. On Wed, 12 Feb 2003 23:57:02 +0000 Steve Harris <S.W.Harris(a)ecs.soton.ac.uk> wrote: > Just to follow up, I rebuilt my test code on gcc3, and it went from C++ > being around 30% slower, to about 1% faster, which is what I expected to > see in the first place. I guess they fixed the optimizer deficiency. As a C fan I was rather curious about this. I didn't want people getting the wrong impression that C++ is automatically faster than C (it isn't) or that in the long term improvements in the C++ compiler will make it faster than C (it won't). So I asked Steve for more details and he pointed me at the code: http://plugin.org.uk/filter/ and suggested that further discussion of this issue should probably be moved from the jackit-devel list to this one. So here we are. (Steve, please don't take this as a slight on you, I simply want to get the facts right). For those interested, my machine is a dual 450Mhz PIII, with SCSI disks, 2.4.20 kernel and running Debian Testing. All compilers and toolchain programs are from Debian Testing; none have been compiled from source. Debian is rather nice in that it allows more than one compiler to be installed on a machine at anyone time. Here are the compilers I used for my testing: erikd@coltrane > gcc-2.95 -v Reading specs from /usr/lib/gcc-lib/i386-linux/2.95.4/specs gcc version 2.95.4 20011002 (Debian prerelease) erikd@coltrane > g++-2.95 -v Reading specs from /usr/lib/gcc-lib/i386-linux/2.95.4/specs gcc version 2.95.4 20011002 (Debian prerelease) erikd@coltrane > gcc-3.2 -v Reading specs from /usr/lib/gcc-lib/i386-linux/3.2.1/specs Configured with: /mnt/data/gcc-3.1/gcc-3.2-3.2.1ds2/src/configure -v --enable-languages=c,c++,java,f77,proto,objc,ada --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --with-gxx-include-dir=/usr/include/c++/3.2 --enable-shared --with-system-zlib --enable-nls --without-included-gettext --enable-java-gc=boehm --enable-objc-gc i386-linux Thread model: posix gcc version 3.2.1 20020924 (Debian prerelease) erikd@coltrane > g++-3.2 -v Reading specs from /usr/lib/gcc-lib/i386-linux/3.2.1/specs Configured with: /mnt/data/gcc-3.1/gcc-3.2-3.2.1ds2/src/configure -v --enable-languages=c,c++,java,f77,proto,objc,ada --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --with-gxx-include-dir=/usr/include/c++/3.2 --enable-shared --with-system-zlib --enable-nls --without-included-gettext --enable-java-gc=boehm --enable-objc-gc i386-linux Thread model: posix gcc version 3.2.1 20020924 (Debian prerelease) And here are the results running Steve's tests (neglecting the Objective C tests because my system seems to be missing something): Compiler Program Cycles -------- ------- ------ gcc-2.95 ansic.c 85058 g++-2.95 cpp.C 90719 gcc-3.2 ansic.c 196581 g++-3.2 cpp.C 85042 Thats all a little strange. So lets look at the code. In cpp.C, Steve defines a Lowpass class and its process member functions like this: class LowPass { private: float ym1; float a; public: void setA(float newa); void reset(); float process(float x); }; float LowPass::process(float x) { float y = ym1 * (1.0f - a) + x * a; ym1 = y; return y; } while the C version is defined like this: typedef struct { float ym1; float a; } lowpass; float lowpass_process(lowpass *this, float x) { float y; y = this->ym1 * (1.0f - this->a) + x * this->a; this->ym1 = y; return y; } So what is going on here? Well my guess is that both versions of g++ and the older version of gcc are applying an optimisation that the new gcc isn't and my guess is that the missing optimisation is function in-lining. So why was in-lining present in gcc-2.95 and absent in gcc-3.2? Thats probably because gcc-3.2 is working towards compliance with the C1999 ISO Standard. In C99, inline is a new C keyword. If I now change the lowpass_process function as follows: inline float lowpass_process(lowpass *this, float x) { float y; y = this->ym1 * (1.0f - this->a) + x * this->a; this->ym1 = y; return y; } and add -std=c99 to the gcc-3.2 command line, the new results are: Compiler Program Cycles -------- ------- ------ gcc-3.2 ansic.c 86299 g++-3.2 cpp.C 85042 So, g++-3.2 is still beating gcc-3.2. However, if g++ is in-lining one function, its probably in-lining them all. Adding inline to all functions in ansic.c gets these results: Compiler Program Cycles -------- ------- ------ gcc-3.2 ansic.c 85044 g++-3.2 cpp.C 85042 which is a 0.002 percent difference. My guess is that even this small difference is purely in the start-up code which is completely irrelevant when the speed that matters is in the processing loop. This little exercise shows that there is more to benchmarking than just getting results. Once you have results, you have to: 1) Compare the results with other results (ie gcc-3.2 and g++-32. vs gcc-2.95 and g++-2.95). 2) Analyze the results and figure out why you get the results you get (in this case, by compiling to assembler it would have obvious that gcc-3.2 was not by-default in-lining functions while the others were). I think that for applications like audio processing where speed is one of the main goals benchmarking is extremely important. Personally I would love to see more people do it properly and publish their results like I did here: http://www.mega-nerd.com/FPcast/ Results like these are repeatable and verifiable. Cheers, Erik -- +-----------------------------------------------------------+ Erik de Castro Lopo nospam(a)mega-nerd.com (Yes it's valid) +-----------------------------------------------------------+ When a user mailbombs me with 100,000 messages, we call it denial of service and the guy can be thrown in jail. When 100,000 SPAMMERS send me one mail each, we call it marketing.

21 years, 7 months

[linux-audio-dev] ecasound 2.2.1 released

by Kai Vehmanen

1. A short summary of changes The JACK slave mode code has been completely rewritten. As a new feature it is now possible to use libsamplerate for resampling. Using JACK has been made more user-friendly as ecasound can now automatically configure the runtime parameters to match the current server settings. And thanks to build system and signal handling updates, it's now possible to compile ecasound for win32 under Cygwin. --- 2. What is ecasound? Ecasound is a software package designed for multitrack audio processing. It can be used for simple tasks like audio playback, recording and format conversions, as well as for multitrack effect processing, mixing, recording and signal recycling. Ecasound supports a wide range of audio inputs, outputs and effect algorithms. Effects and audio objects can be combined in various ways, and their parameters can be controlled by operator objects like oscillators and MIDI-CCs. A versatile console mode user-interface is included in the package. Ecasound is licensed under the GPL. The Ecasound Control Interface (ECI) is licenced under the LGPL. --- 3. Changes since last release * If configured with JACK-support, ecasound will now fetch the correct buffer size and sampling rate parameters from the JACK server when connecting a chainsetup with JACK inputs or outputs. In other words you don't have to manually match these settings between the JACK server and ecasound. * Support for Erik de Castro Lopo's libsamplerate resampling library added. If libsamplerate is not installed, ecasound will fall back to the old resampling algorithm. * Rewritten the code that handles JACK slave-mode operation. Ecasound is now able to more quickly and reliably follow transport state and position changes, as initiated by the current JACK timebase master. * Ecasound for Windows! :) With help of the Cygwin environment, you can now compile win32 ecasound binaries straight from the standard source package. As of 1.3.1, Cygwin also contains basic /dev/dsp emulation, so even audio playback works. * Fixed many, more or less serious, bugs. The most annoying ones were incorrect handling of the '-t' option, excessive DBC warnings with JACK inputs and outputs and failing to properly reset the terminal after a CTRL-C while in interactive mode. Full list of changes is available at <http://www.wakkanet.fi/~kaiv/ecasound/history.html>. --- 4. Interface and configuration file changes None. --- 5. Contributors Patches Junichi Uekawa (build system) Kai Vehmanen (various) Bug Hunting (items closed) Janne Halttunen (2) Eric Amundsen (1) Antti Boman (1) William Goldsmith (1) Andrew Reilly (1) Oliver Thuns (1) --- 6. Links and files Web sites: http://www.eca.cx http://www.eca.cx/ecasound Source packages: http://ecasound.seul.org/download http://ecasound.seul.org/download/ecasound-2.2.1.tar.gz Related sites: http://jackit.sf.net (JACK) http://www.mega-nerd.com/SRC (libsamplerate) http://www.cygwin.com Distributions with maintained ecasound support: Agnula - http://www.agnula.org Debian - http://packages.debian.org/stable/sound/ecasound.html http://packages.debian.org/unstable/sound/ecasound2.2.html DeMuDi - http://www.demudi.org FreeBSD - http://www.freebsd.org/ports/audio.html Gentoo Linux - http://www.gentoo.org PLD Linux - http://www.pld.org.pl PlanetCCRMA - http://www-ccrma.stanford.edu/planetccrma/software SuSE Linux - http://www.suse.de/en Contrib Packages for Distributions: Mandrake - http://rpm.nyvalls.se/sound9.0.html Note! Distributors do not necessarily provide packages for the very latest ecasound version. -- http://www.eca.cx Audio software for Linux!

21 years, 7 months

[linux-audio-dev] [ANN] JACK Rack 1.4.0

by Bob Ham

Just one thing but it totally rocks :) Right click on some controls. * MIDI support http://pkl.net/~node/jack-rack.html Bob -- Bob Ham <rah(a)bash.sh>

21 years, 7 months

[linux-audio-dev] Damned .org domains...

by David Olofson

Well, here's the reason for the delay: The .org domains are being moved to some other maintaner, and as a result, domain info is totally screwed up. xap.org has been taken for almost 3 years, apparently by the same owner as xap.net... :-/ (I did get audiality.org while I was at it, but that's to be expected. Weird names have their advantages...) Now, should I try some others instead? xapaudioplugins.org (*heh*) or whatever? Not all that interesting, of course... Well, I could try and contact the owner of xap.org. Doesn't seem to be Xap Corporation (who owns xap.com), but they'll probably want some extra bucks anyway. //David Olofson - Programmer, Composer, Open Source Advocate .- The Return of Audiality! --------------------------------. | Free/Open Source Audio Engine for use in Games or Studio. | | RT and off-line synth. Scripting. Sample accurate timing. | `---------------------------> http://olofson.net/audiality -' --- http://olofson.net --- http://www.reologica.se ---

21 years, 7 months

[linux-audio-dev] [Survey] sounds on mobos / notebooks with "headphone" as master

by Takashi Iwai

Hi, i'm gathering the hardware information for workarounds of the "headphone / master swap" problem. on some onboard sound chips and notebooks, the "headphone" volume is used as "master" volume. if you have such a device, please let me know the following: 1. the name of the device (mobo, notebook) 2. whether "master" is connected to any jack? 3. output of "lspci -xv" (of the multimedia entry only) 4. output of "lspci -nv" (of the multimedia entry only) 5. ac97 codec name (found in /proc/asound/card0/ac97#0) thanks in advance, -- Takashi Iwai <tiwai(a)suse.de> SuSE Linux AG - www.suse.de ALSA Developer ALSA Project - www.alsa-project.org

21 years, 7 months

[linux-audio-dev] why is no-one responding are you all just a bunch of &*^%&^%^& wits???

by Allan Klinbail

Hi Guys This is quite a disturbing message.. nearly 2 weeks ago Paul Davis marked one of my messages as something "seriously wrong" going on .. when libraries were compiling as dynamic not static... since then I have responded with full outputs of what is happening. In response I sent full output of what was going on .. tried to sort it out by myself and sent further results.. Okay some of it was too big to get to the list immediately pending "list moderator" acceptance.. and then some of it just purely didn't get responded to. I have done everything I have asked of me from the list, including Paul's responses ..and also taken my own initiatives following lack of response and still have recieved no response. Sure I am not a coder just a potential professional user.. but that really shouldn't be an issue... Okay some individuals responded to some of my initial questions, and thankyou to the two of them.. however noone has responded to further enquiries, after acting on the responses I did get.. Is it because I feigned mild support to Steinberg having (while unreleased) versions of their software for Linux?? Or is it because I'm obviously not a coder?? Is it simply because I used the wrong subject line? This disgusts me as about 2 years ago when I said I was going to give up on Linux to the LAD lists a massive response came about saying I should keep going and my opinions (not even problems relating to software directly) were valued and necessary. Now when I have real problems compiling something, contained with as much information I could forward were included it seems it is irrelevant and no-one seems willing to respond at all (let alone Paul) .. Other compile and/or configure problems have been responded too earlier than mine (at all really as my last few posts have not received any reply) even though I acted upon all requests made of me. I am active in all lists that I am involved in with any replies that I may have a potential answer to and have been promoting this OS and in particular the potential of Ardour to many fellow professionals in the industry. I also have rad and learnt as much as I could to give qualitative feedback to any problems I incur. All I seek is the ability to use open source software in preference to rip-off commercial apps. Yes, I admit there is potential for both to exist on this platform and would use some commerical apps to aide in crossover but that is not the point of this (ardour-dev) list. It would seem only the MusE list responds to anything I send, and only a few particular individuals at that. Aside from being upset, it appears to me that you guys are all a bunch of hypocrites.. Asking for further information, and clarification but never actually responding, while I do everything that I can possibly thing\k of in aiding you answer my questions.. yet continue to be ignored... It does not seem to be a coincidence that all response ended after my response to the string "ahem". So I've wasted 2+ years of my life and countless dollars continuing down this path. Yes this is an emotional response as it seems like my friends advised me I should have just bought a Mac ,, inferior latency aside.. at least the support groups there (even those non-funded as this list) genuinely help. My only problem is , where do I go from here?? This really saddens me as I thought this (Linux) was the future. It seems it is only a future for the GPL elite. extremely pissed off Allan Klinbail

21 years, 7 months

[linux-audio-dev] ZynAddSubFX 1.0.8

by Nasca Paul

I relased today zynaddsubfx 1.0.8 at sourceforge. News: - added mono mode and portamento - added the EQ effect - the output of the system effects can be sent to other system effects - minor bugfixes and improovements Get it from http://zynaddsubfx.sourceforge.net __________________________________________________ Do you Yahoo!? Yahoo! Shopping - Send Flowers for Valentine's Day http://shopping.yahoo.com

21 years, 7 months

Re: [Alsa-devel] Re: [linux-audio-dev] Re: why is no-one responding are you all just a bunch of &*^%&^%^& wits???

by Takashi Iwai

At Wed, 12 Feb 2003 11:49:08 -0500, Paul Davis wrote: > > when ardour is in a state where i believe (rightly or wrongly) that a > reasonably typical target user can sit down and just use it without > encountering bugs when recording a typical 12-32 track piece, there > will be binaries. don't forget that the binary distribution may cause different kind of problems, too. the binary might not run on different distributions, or even on a different machine with a same distribution, unless you give all-static-linked binary. (note that even a binary like netscape 4.x cannot run properly now with the new glibc because of java.) and you would likely ignore a bug-report for such, because the only answer is "it works for me" :) Takashi (in a pessmistic atmosphere)

21 years, 7 months

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Linux-audio-dev