Linux-audio-dev April 2010

linux-audio-dev@lists.linuxaudio.org

65 participants
45 discussions

LAC 2010 live stream coverage

by Jörn Nettingsmeier

hi everybody! the Linux Audio Conference 2010 (hosted this year by the Hogeschool voor de Kunsten, Utrecht) will have live streaming coverage of all the paper presentations and selected workshops, just like in the old days. the streams will be available via http://streamer.stackingdwarves.net and at least two other relays, which will be announced as they come online. for remote participants, there is an IRC channel called #lac2010 on irc.freenode.net, which serves as a backchannel for your questions and comments, hangout for conference chatter, and helpdesk for any streaming troubles you might encounter. spread the word, and join the fun. LAC 2010 takes place from may 1st to may 4th. test streams will be made available a few days in advance. the IRC channel is already open. the official lac site is at http://lac.linuxaudio.org/2010/. best regards, on behalf of the stream team, jörn

14 years, 11 months

Re: [LAD] successive note on midi events

by James Morris

On Mon, April 12, 2010 00:38, James Morris wrote: > Hi, > > I'm pretty sure I've seen this dealt with on the list before, but can't > find it. > > With the program I'm fumbling around trying to create, it will be possible > for successive note on events for the same pitch to occur without note off > events intervening. > > Does the MIDI spec allow such things? Sorry to answer myself so soon... I guess it is allowed. The simplest case being a sequencer outputting to the same channel and port as a keyboard player. Nothing can prevent this - right? And there's no way in the world that missing note-offs could be added in, in a fashion guaranteed to cover all possible permutations of connections, or without delaying the note-on which implies a missing note-off. James. > The bash-script prototype of the program did this, and, I believe, the > soft-synths used, acted appropriately - that is, re-triggered the notes. > So I guess the question is, does it make any difference if I add-in the > note-off events - which, thinking about it, is going to be tricky because, > basically, although the program is sequencing, it will be real time and is > not psychic! > > > Cheers, > James. > > _______________________________________________ > Linux-audio-dev mailing list > Linux-audio-dev(a)lists.linuxaudio.org > http://lists.linuxaudio.org/listinfo/linux-audio-dev >

14 years, 11 months

Re: [LAD] successive note on midi events

by James Morris

On Mon, April 12, 2010 12:47, James Morris wrote: > 2) when a missing note-off detected, delay the note-on by the smallest > amount of time possible, and insert the note-off in place of it. Any thoughts on that? Or send a note-off for pitch n followed by a note on for pitch n within the same MIDI data stream? For the sake of pretending correctness? James.

14 years, 11 months

Interface development for the blind (starting from Bristol)

by Julien Claassen

Hello! so as has been suggested on LAU, I moved this discussion back on-list, but thought it would be more relevant to the LAD than LAU for obvious reasons. Maybe some general points. Blind or visually impaired people most work with one of these technologies: Braille display, Speech synthesis (text-to-speech) or magnifier. The latter is, I think, the easiest to accomodate, as GNOME and basic X!! offers screen mags. Braille displays and speech synths are in general one dimensional tools. Both can work with graphics, yet there are restrictions. 1. The only project for both braille and TTS for GUIs I know is Orca, which needs Gnome/GTK. I suppose it's also relying on standard widgets. Then there is the fact, that I'm not certain about its usability/stability. A few win and linux users, I know, said, that Orca is far from comfortable, in comparison to windows solutions. 2. Graphics rely on 2-dimensionality. That's - in my books - all it's about. It's designed for the sighted person, being able to use his field of vision, other markers than only text to transport information to the user. Speech ingeneral is - again only from my point of view - not very suitable for audio, for obvious reasons again. I got festival to work with JACK, but it's not nice and not everyone using speech, has two soundcards, to make it really convenient. But that's just an aside. So seeing all this, the best way to interact is the console/CLI interfaces. The best amongst these are readline interfaces. Applications, which look like shells. to make this really helpful and nice (the equivalent of eye-candy) a nice kind of online help is forunite. A good example - not to say superb - is Nama. You have the command help. It works with category names, category numbers, keywords and actual commandnames. That's really taking it to the height of convenience and comfortability. A short note about ReadLine. It's written in C, for those, who haven't yet seen/used it. There is a c++ wrapper called rlmm, which hasn't seen development for some time, as far as I'm aware. Yet Readline hasn't changed it's interface drastically, I believe. Readline itself offers two ways of usage: Directly or via callback-functions. This is what rlmm uses. rlmm is also GPL, so if you don't want to use it as an external reference, I'm sure you can include it in your code, modify it to your liking. I remember, that it isn't big. Another way to interface is ncurses (with menus and forms and all the rest). Yet that can be tricky. You have to take care of the cursor (the hardcursor!) Always moving it to the current element. Don't rely on seeintg attributes. Braille displays like to attach to the real cursor and focus on it by default, which is good, because , where the cursor is, there should be the action and it's easy to follow it (I think). I also think, the same applies for TTS systems. So with ncurses you'd have to take care of some restrictions beyond the library itself. One other of these restrictions (for comfort) would be to draw progressbars or percentage bars - like in a mixer - horizontally. That's the way a braille display is oriented. Most braille displays have 40 characters, there are those with 80 characters, but they're mostly designed for home or workplace systems. The 40 character displays can serve nicely at home (most of the blind people I know, have one) and they can easily fit under a laptop. And I believe they are cheaper, so the health insurance, which mostly pays for it, is happier with it. :-) Applications, which have both GUIs and CLIs are: Aeolus (restricted CLI, yet helpful). But Fons relies - I seem to remember - on his own UI-classes. Still, he makes use of callback functions, if I'm right. Nama is written in Perl, it also offers both a GUI and a CLI. Yet I'm not completely sure, how much interconnection there is between the two. I believe, they are quite seperate. There's links2, which I think has both CLI and GUI, it's a web-browser, and should be available as packages on all major distros. It uses ncurses for displaying information. The SuSE Yast2 system, has both an ncurses and a graphical interface. But the ncurses interface is nothing to show off, to a blind person at least. (Last seen 2005/06, so that MAY have changed). And now I'm open to specific questions. Kindly yours Julien -------- Music was my first love and it will be my last (John Miles) ======== FIND MY WEB-PROJECT AT: ======== http://ltsb.sourceforge.net the Linux TextBased Studio guide ======= AND MY PERSONAL PAGES AT: ======= http://www.juliencoder.de

14 years, 11 months

successive note on midi events

by James Morris

Hi, I'm pretty sure I've seen this dealt with on the list before, but can't find it. With the program I'm fumbling around trying to create, it will be possible for successive note on events for the same pitch to occur without note off events intervening. Does the MIDI spec allow such things? The bash-script prototype of the program did this, and, I believe, the soft-synths used, acted appropriately - that is, re-triggered the notes. So I guess the question is, does it make any difference if I add-in the note-off events - which, thinking about it, is going to be tricky because, basically, although the program is sequencing, it will be real time and is not psychic! Cheers, James.

14 years, 11 months

yoshimi and the Space Choirs reconciled at last

by cal

0.056 2010-04-12 reinstates PADsynth functionality - a stuff up in XMLwrapper::getparbool(); no other changes worth mentioning. <http://sourceforge.net/projects/yoshimi/files/> and that one was really horrible to find ... educational though :-(.

14 years, 11 months

Jack working on ARM?

by nescivi

Hiho, is Jack working on this processor: CORTEX A8 ARM ? I'm looking at this board right now: http://www.igep-platform.com/ There is an Ubuntu available for it... sincerely, Marije

14 years, 11 months

Updates

by fons＠kokkinizita.net

Some updates on <http://www.kokkinizita.net/linuxaudio/downloads> jconvolver-0.8.7 Bugfixes to fconvolver, now exits cleanly. Thanks to Joern Nettingsmeier for reporting this bug. zita-resampler-0.1.1 Library is not changed, new version of the audio file resampling application. For 16-bit output 'resample' now supports dithering: rectangular, triangular or 'noise shaped' using the Lipschitz filter. Enjoy ! -- FA O tu, che porte, correndo si ? E guerra e morte !

14 years, 11 months

jack1 and netjack -M

by alex stone

Recently the -M switch was added to jack1 as a means to independently set the jackmidi buffer size. (and it works well, i hasten to add.) Is this also true for the netjack driver in jack1? Can we independently set the jackmidi buffer on a netjack slave in the command line? Alex. -- www.openoctave.org midi-subscribe(a)openoctave.org development-subscribe(a)openoctave.org

14 years, 11 months

does sndfile-convert apply dither when reducing wordlength?

by Jörn Nettingsmeier

if not, an option to do so would be cool. best, jörn

14 years, 11 months

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Linux-audio-dev April 2010