Linux-audio-dev

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7520 discussions

RE: [linux-audio-dev] Quick and efficient sound daemon idea -- wh y not do it this way?

by STEFFL, ERIK (SBCSI)

> -----Original Message----- > From: Ivica Bukvic [mailto:ico@fuse.net] ... > introduces a problem of porting apps into its API, and that > again poses > the same problem of excluding a lot of older audio apps that ... this might be solved by user space device drivers - they do not want the mixer in kernel... once the userspace device drivers are available it will be possible to implement what you propose, I guess. not sure what's the latest news as far as the userspace device drivers go... the other option is that one of the APIs will become roughly as common as OSS is today (so that virtually no applications will go straight to device drivers). JACK? erik

23 years, 2 months

[linux-audio-dev] Announcing initial release of FreqTweak

by Jesse Chappell

Announcing the initial release of FreqTweak (v0.4) http://freqtweak.sourceforge.net FreqTweak is a tool for FFT-based realtime audio spectral manipulation and display. It provides several algorithms for processing audio data in the frequency domain and a highly interactive GUI to manipulate the associated filters for each. It also provides high-resolution spectral displays in the form of scrolling- raster spectragrams and energy vs frequency plots displaying both pre- and post-processed spectra. It currently relies on JACK for low latency audio interconnection and delivery. Thus, it is only supported on Linux. FreqTweak is an extremely addictive audio toy, I have to pry myself away from playing with it so I can work on it! I hope it has value for serious audio work too (sound design, etc). The spectrum analysis is pretty useful in its own right. FreqTweak supports manipulating the spectral filters at several frequency resolutions (64,128,256,512,1024, or 2048 bands) depending on your needs and resources. Overlap and windowing are also selectable. The GUI filter graph manipulators (and analysis plots) have selectable frequency scale types: 1x and 2x linear, and two log scales to help with modulating the musical frequencies. Filters can be linked across multiple channels. The plots are resizable and zoomable (y-axis) to allow precise editing of filter values. The current processing filters are described below in the order audio is processed in the chain. Any or all of the filters can be bypassed. The state of all filters can be stored or loaded as presets. Spectral Analysis -- Multicolor scrolling-raster spectragram, or energy vs. freq line or bar plots... one shows pre-processed, another shows post-processed. EQ -- Your basic multi-band frequency attenuation. But you get an unhealthy number of bands... Pitch Scaling -- This is an interesting application of Sprengler's pitch scaling algorithm (used in Steve Harris' LADSPA plugin). If you keep all the bins at the same scale, it is equivalent to Steve's plugin, but when you start applying different scales per frequency bin, things quickly get weird. Gate -- This is a double filter where a given frequency band is allowed to pass through (unaltered) if the power on that band is between two dB thresholds... otherwise its gain is clamped to 0. Delay -- This lets you delay the audio on a per frequency-bin basis yielding some pretty wild effects (or subtle, if you are careful). A feedback filter controls the feedback of the delay per bin (be careful with this one). This is basically what Native Instrument's Spektral-Delay accomplishes. Granted, I don't have all the automated filter modulations (yet ;). See their website for audio examples of what is possible with this cool effect. Have fun... report bugs... Jesse Chappell <jesse(a)essej.net>

23 years, 2 months

[linux-audio-dev] Novation Supernova experience, anyone?

by Frank Neumann

Hi list, sorry for abusing this list yet again for a not directly LAD related issue, but.. does anyone here own (or have experience with) the Novation Supernova II synthesizer? I want to extend my MIDI park at home a little around Christmas, and this one looks like an interesting candidate to me. Things I'm interested in are: Overall opinion, weak spots, support from Novation, reasons why you would not buy it. Also, if there are recommendations for comparable systems from another company, I'm also interested in that. And, does the machine come with a complete SysEx implementation chart? I downloaded the PDF manual, but it doesn't contain anything like that.. Thanks, and please reply in private mail unless lots of people on this list start shouting "me wanna know, too" :-). Frank

23 years, 2 months

[linux-audio-dev] waveform overview

by Thomas Grill

Hi all, can anyone give me pointers on how the overview cache for a zoomable waveform display is organized? One can see accurate and fast displays in a lot of applications but i guess the rendering of this is not straightforward. best greetings, Thomas

23 years, 2 months

[linux-audio-dev] sfront 0.85 10/13/02 released

by John Lazzaro

Pick up sfront 0.85 -- 10/13/02 at: http://www.cs.berkeley.edu/~lazzaro/sa/index.html [1] Mac OS X support for real-time MIDI control, using the -cin coremidi control driver. Up to four external MIDI sources are recognized. Virtual sources are ignored; expect virtual source support in a future release. [2] Mac OS X memory locking now works in normal user processes, and is no longer limited to root. ----- All the changes in 0.85 are OS X specific, but thought I'd post this here in case people are curious about OS X porting ... With this release, all of the real-time examples in the sfront distribution run under Mac OS X. Specifically, its now it's possible to use OS X as a Structured Audio softsynth -- I've been running my PowerBook this way with 2ms CoreAudio buffers, with MIDI input from my controller via an Edirol UM-1S USB MIDI interface, and audio output via the headphone jack on the Powerbook, and things work glitch-free. Also, because audio and MIDI are both virtualized under OS X, its possible to run multiple ./sa softsynths in parallel (i.e. from different Terminal windows) and get useable layering ... although in most cases, you'd be better off doing your layering inside a single SA engine. To see the -cin coremidi control driver in action, run the sfront/examples/rtime/linbuzz softsynth, it will find external MIDI sources (up to 4, no virtual source support ...) and use them to drive the SA program in real-time. In the linbuzz example, the pitch wheel (set up to do vibrato) mod wheel (spectral envelope) and channel volume controllers are all active -- you can look at the linbuzz.saol SAOL program to see how they are used. The actual CoreMIDI code is in: sfront/src/lib/csys/coremidi.c The most interesting aspect of this code is that a single AF_UNIX SOCK_DGRAM socketpair pipe (named csysi_readproc_pipepair) is used for communication between an arbitrary number of CoreMIDI readprocs (one for each active source) and the SA sound engine (which runs inside the CoreAudio callback -- the actual main thread sleeps and does nothing). Writing the pipe is blocking (but should rarely block, and never for significant time), but reading the pipe is non-blocking. The semantics of the AF_UNIX SOCK_DGRAM (AF_UNIX is reliable, SOCK_DGRAM guarantees the messages from the CoreMIDI readprocs don't mix) makes it a good choice for doing the multi-source MIDI merge. The actual messages sent in the pipe consists of a preamble to identify the readproc, and the (error-checked for SA semantics) MIDI commands in each MIDIPacket. At this point, the Linux and OS X real-time implementations support all of the same features (audio input, audio output, MIDI In, RTP networking) ... I'm not sure if AudioUnits support makes sense for sfront, I'll probably take a closer look at the issue soon ... ------------------------------------------------------------------------- John Lazzaro -- Research Specialist -- CS Division -- EECS -- UC Berkeley lazzaro [at] cs [dot] berkeley [dot] edu www.cs.berkeley.edu/~lazzaro -------------------------------------------------------------------------

23 years, 2 months

[linux-audio-dev] latency performance of 2.4 and 2.5...

by Joern Nettingsmeier

hi andrew, hi everyone ! as per your request, i fearlessly built and booted 2.5.41 with preemption enabled. although it was my first take at the dev kernel, it went very smoothly :-D anyway, it seems to perform worse than 2.4.20-pre1-lowlatency. it feels very snappy on startup, but under load it is a lot less responsive to user interaction. i have run benno senoner's latencytest on both kernels. you can see the results at http://spunk.dnsalias.org/latencytest . for me, the biggest problem seems to be soft-raid. i have my /var partition striped over 2 scsi disks, and accessing them causes huge latency peaks. is there any chance to get this under control ? i don't have a spare disk around, so i can't easily compare to non-raid, but i'm quite sure it's the source of the problem, because people with similar hardware are doing fine. other than that, there were a few peaks under /proc stress, but they are not easily reproducible. i have not yet tested your mm-patches due to a compile failure (log is attached below). i used http://www.zip.com.au/~akpm/linux/patches/2.5/2.5.41/2.5.41-mm3/2.5.41-mm3.…. if there's any patches to try or more benchmarks to run, let me know. best, jörn *** Hardware: Dual-P3 @ 600Mhz, 512MB PC100 SDRAM, ASUS P2B-DS one 4G IBM DCAS SCSI disk (/), 2 9G COMPAQ SCSI disks (/var, soft-RAID 0), SCSI CDROM and CDR, no IDE devices. Soundcards: SB Live (used during the tests) and Ensoniq 1371 (idle) The audio file that was played back during the tests came over NFS. *** make -f init/Makefile Generating include/linux/compile.h (updated) gcc -Wp,-MD,init/.version.o.d -D__KERNEL__ -Iinclude -Wall -Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing -fno-common -pipe -mpreferred-stack-boundary=2 -march=i686 -Iarch/i386/mach-generic -fomit-frame-pointer -nostdinc -iwithprefix include -DKBUILD_BASENAME=version -c -o init/version.o init/version.c ld -m elf_i386 -r -o init/built-in.o init/main.o init/version.o init/do_mounts.o ld -m elf_i386 -e stext -T arch/i386/vmlinux.lds.s arch/i386/kernel/head.o arch/i386/kernel/init_task.o init/built-in.o --start-group arch/i386/kernel/built-in.o arch/i386/mm/built-in.o arch/i386/mach-generic/built-in.o kernel/built-in.o mm/built-in.o fs/built-in.o ipc/built-in.o security/built-in.o lib/lib.a arch/i386/lib/lib.a drivers/built-in.o sound/built-in.o arch/i386/pci/built-in.o net/built-in.o --end-group -o .tmp_vmlinux1 fs/built-in.o: In function `isofs_put_super': fs/built-in.o(.text+0x390e5): undefined reference to `unload_nls' fs/built-in.o: In function `isofs_fill_super': fs/built-in.o(.text+0x39f0b): undefined reference to `load_nls' fs/built-in.o(.text+0x39f25): undefined reference to `load_nls_default' fs/built-in.o(.text+0x3a0c6): undefined reference to `unload_nls' fs/built-in.o: In function `wcsntombs_be': fs/built-in.o(.text+0x3c60b): undefined reference to `utf8_wctomb' make: *** [.tmp_vmlinux1] Error 1 -- Jörn Nettingsmeier Kurfürstenstr 49, 45138 Essen, Germany http://spunk.dnsalias.org (my server) http://www.linuxdj.com/audio/lad/ (Linux Audio Developers)

23 years, 2 months

[linux-audio-dev] Tapiir

by Miha Tomsic

Hello Maarten and other LAD(y)s! I am having some problems with tapiir 0.6. It seem's I can't get it to run with SCHED_RR. I can run it with suid or as root and still I am getting: josef:/usr/src/tapiir-0.6/src# ./tapiir !!!Scheduler set to Round Robin with priority 99 FAILED!!! Make sure you are root, or that tapiir has the suid flag set ( chmod 4755 ) Any idea why this is happening? Thanks and take care, Miha...

23 years, 2 months

[linux-audio-dev] Tk Ecasound 0.8.1 Released!

by Luis Pablo Gasparotto

Download it from: http://www.sourceforge.net/projects/tkeca Changes: - Bug fixed in Close/Ok button in Recording/Mixdown Properties Windows Regards, Luis Pablo Ahora pod�s usar Yahoo! Messenger desde tu celular. Aprend� c�mo hacerlo en Yahoo! M�vil: http://ar.mobile.yahoo.com/sms.html

23 years, 2 months

[linux-audio-dev] Tk Ecasound 0.8.0 Released!

by Luis Pablo Gasparotto

Download it from: http://www.sourceforge.net/projects/tkeca Changes: - Recording / Mixdown properties windows Regards, Luis Pablo Ahora pod�s usar Yahoo! Messenger desde tu celular. Aprend� c�mo hacerlo en Yahoo! M�vil: http://ar.mobile.yahoo.com/sms.html

23 years, 2 months

Re: [linux-audio-dev] latency performance of 2.4 and 2.5...

by Joern Nettingsmeier

Peter L Jones wrote: > > On Friday 11 Oct 2002 13:48, Joern Nettingsmeier wrote: > [snip] > > i have run benno senoner's latencytest on both kernels. you can see the > > results at > > > > http://spunk.dnsalias.org/latencytest . > > > > Jörn, could you post the latencytest URL, please. > > Thanks, > > -- Peter http://www.gardena.net/benno/linux/latencytest-0.42-png.tar.gz -- Jörn Nettingsmeier Kurfürstenstr 49, 45138 Essen, Germany http://spunk.dnsalias.org (my server) http://www.linuxdj.com/audio/lad/ (Linux Audio Developers)

23 years, 2 months

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Linux-audio-dev