Pd Documentation 3

+ + +Pd Documentation chapter 3: Getting Pd to run + +
+ back to table of contents +

+ +Pd runs under Irix, Windows, and Linux. +How to get Pd up and running depends on your operating system, +but the overall strategy is the same. +You must first get and install it, and +then untangle whatever problems arise in handling audio and MIDI input +and output, and finally get Pd to meet its real-time obligations reliably. + +In case of trouble also consult the Pd mailing list archive on + + http://iem.kug.ac.at/mailinglists/pd-list/ +, which often has late-breaking news about configuration problems and solutions. + + +

+You may be interested in getting only audio output or audio input, or +you may need both to run simultaneously. By default, Pd will try to run +both, but if you don't need either input or output, you may find that Pd +runs more reliably, or at least more efficiently, with the unused direction +turned off. This is controlled by Pd's command line flags. + +

+Depending on your application you will have a more or less stringent latency +requirement. Ideally, when any input (audio, MIDI, keyboard, network) is +available, the outputs (in particular the audio output) should react instantly. +In real life, it is necessary to buffer the audio inputs and outputs, trying +always to keep some number of milliseconds ahead of real time to prepare for the +inevitable occasions where the CPU runs off to service some different task +from Pd. How small this latency can be chosen depends on your OS and your +audio driver. + +

+To test audio and MIDI, start Pd and select "test Audio and MIDI" from the +"help" menu. + +

TIP: If Pd starts up but you get distortion or glitches in the audio +output, this could be either because the "audio I/O buffer" isn't big enough, +or else because the CPU load of the patch you're running is too great for the +machine you have, or else because the ADC and DAC are out of sync or even at +different sample rates. To test for the first possibility, try increasing the +"-audiobuf" parameter in the command line (but see also under your OS below.) +For the second, start up your favorite performance monitor program; and for the +third, try starting Pd up with ADCs disabled. + +

Here are instructions for getting and installing Pd for the four +operating systems it runs on: IRIX, MS Windows, Linux, and Max OSX. + +

3.1. IRIX (SGI machines)

+ +

Download Pd, which will be a "tar.Z" file. You can unpack this by +typing "zcat [name].tar.Z | tar xf -" to a shell. This creates a directory +named "pd". + +

+Starting with release 0.25, Pd should come in "n32" and "o32" versions. +"o32" is the default and will run on IRIX 5.x and up. "n32" runs faster, +but only on 6.x and up. Also, "externs" have to be updated for n32. The +"pd" executable (bin/pd in the distribution) is a symbolic link to either +"pd-o32" or "pd-n32." + +

NOTE: "externs" appear to be broken in the N32 version... I'm not sure +how long this has been true. If you want to use external objects, you have +to use the O32 version. + +

+Please note that the path to the Pd executable program can't contain +space characters; don't put it in a directory named "Program Files" +for example. + +

+If for example you put Pd in ~, the executable program +will be ~/pd/bin/pd. The program looks at its command line to +figure out where it is, so it's best to invoke Pd by its full pathname. +You should always invoke Pd from a Unix shell because many important +messages appear on the standard error. + +

+The simplest way to invoke Pd is to +make an alias in your ".cshrc" file (assuming you use the "c" shell) such as: +

+
+    alias pd ~/pd/bin/pd
+
+

+(assuming your Pd distribution landed in ~, for example). + +

+Pd will open the "default" audio input and output devices, without regard +for whether they are in sync or not. This will be bad if they aren't; use +the "-noadc" or "-nodac" flag to disable either the input or output. Pd is +supposed to handle up to 8 channels of audio in and/or out. (But at least +one user had to recompile Pd on his Onyx to get 8 channels working.) + +

+As to MIDI, Pd simply attempts to open all available MIDI devices for input and +output, which is probably very bad on anything more recent than my Indy. If +any MIDI ports fail to open either for input or output, all MIDI is disabled. + +

Pd has not been fixed to request real-time priority from Irix; it will +compete with all other processes on your machine for CPU time. + +

Audio and MIDI in IRIX

+ +

+Pd takes command line arguments to set the number of input and output channels +and the sample rate. These don't affect the SGI's audio settings, which you +have to set separately using the "audio panel." Pd does detect the audio +sample rate if you don't specify one on the command line. + +

+On SGI machines, you have to work to get MIDI running. Before you start Pd, verify +that least one MIDI port is configured open. Pd opens the FIRST MIDI port +that's open. You might want to get rid of the "software" MIDI port if you're +running 6.x. On Indys, the usual practice is to open serial port number 2 +because some systems configure port 1 as "console" by default. You can use the +GUI if you want, or else just type +

+
+    startmidi -d /dev/ttyd2
+
+

+to get port 2 speaking MIDI, and +

+
+    stopmidi
+
+

+to stop it. You can test whether MIDI is configured by typing, +

+
+    ps -dafe | grep midi
+
+

+and looking for "startmidi" processes. +

+It's a good idea to connect your serial port to your MIDI interface before +typing the "startmidi" command, not afterward, at least in 5.x. We use the +Opcode Studio 3 interface but in principle any Mac-compatible one should work. + +

+The O2 apparently has RS232 ports, not RS422. I think SGI's web site says +something about how to deal with this. + +

3.2. Microsoft Windows

+ +

Pd is compiled under NT, but shoould work under any version of Windows +since 95. Pd will appear as a "zip" file. Unzip this, creating a directory +such as \pd. (You can put it wherever you like but the path should have no +spaces in it; so "Program Files" would be a bad place.) + +

+If for example you put Pd in C:\pd, the executable program will be +C:\pd\bin\pd. You can simply adjust your path to include C:\pd\bin and just +invoke "pd" in a command prompt window. You can also make a "command prompt" +shortcut to start Pd. + +

Pd requires "TCP/IP networking" to be turned on. This doesn't mean you +have to be on a real network, but simply that Pd actually consists of two +programs that make a "network link" to intercommunicate. + +

The vanishing window

+ +

Pd is a "command line" program. Most error and diagnostic +messages from Pd appear on the command prompt window Pd runs from. + +

If you start Pd from the "run" menu or as a shortcut, and if there's +a problem with run-time flags (see the Pd command line below), Pd will +print an error and exit. You won't see this error unless you arrange for the +"command prompt" or "msdos" window to stay open after Pd exits. One way +to do this is to make a "batch" file ("run.bat", say) containing the Pd +command line. + +

Audio in Microsoft Windows

+ +

+You can ask for a list of audio and MIDI devices by typing +"pd -listdev"; you can then specify which audio and MIDI device to use. +Type "pd -help" (or make any mistake) to get the syntax for specifying +which device to use. + +

+Most PC sound cards seem to have MIDI built in; you don't seem to have to +do anything special to get Pd to send and receive MIDI. You can list and +choose MIDI devices in the same way as audio. + +

+MIDI timing is very poor if you are using simultaneous audio input and output; +if you suppress either audio input or output things will improve somewhat under +NT; you can apparently get the jitter down to ~40 msec. On W95 performance is +simply terrible. W98, with either audio input or output suppressed, offers +fairly good MIDI timing (~5 msec jitter) but crashes occasionally. + +

Some NT and W98 drivers greet you with a constant trail of "resyncing +audio" messages. Sometimes you can fix this by invoking Pd with the "-noresync" +flag. + +

ASIO

+ +

As of version 0.35 Pd supports ASIO. Invoke Pd as "pd -asio" and, if +needed, specify "-sounddev" (etc.) flags to specify which device (see +"the Pd command line" below.) You can also specify a "-blocksize" different +from the default (256 samples) and "-audiobuf" in milliseconds. Pd will +round this down to a power of two buffers, each of "-blocksize" in sample +frames. + +

Using an RME Hammerfall, and specifying "-audiobuf 5 -blocksize 32" I +was able to get about 7 milliseconds of throughput delay (as measured by +the latency-measurement patch in 7.stuff/tools.) As always, you can specify +"-channels" to any even number up to the maximum (32, I think) or can specify +channel count separately for input and output (-inchannels and -outchannels). + +

The special joys of Windows 95

+ +

+On Windows 95 you can expect a hard time. Every user who tries it seems to +encounter a new problem. The best way to run Pd is to get into the "MSDOS +Prompt" program and type \pb\bin\pd to it (or whatever the path ends up being.) +You can probably put pd's "bin" directory in your path so that you just type +"pd" to the prompt. + +

+You don't want to run Pd from the "run" menu because if it fails to start up +the window holding the error message will disappear instantly. Ditto for +clicking on "batch files" or on the Pd executable itself. + +

+The most common reason Pd might fail to start up in W95 is not having +"networking" turned on. Pd is actually two programs that establish an IP +interconnection. Beware that this sometimes fools Windows into calling your +ISP for no reason. + +

+It is often necessary to specify a huge audio buffer to get steady audio +output in W95; see the command line arguments below. + +

3.3. Linux

+ +

What to do depends on which flavor of Linux you are running (e.g., Debian +or Red Hat). The instructions here should work for Pd 0.33 and up regardless of +your situation, but if you have any trouble just mail msp@ucsd.edu and I'll try +to figure out what's wrong and update the instructions accordingly. + +

Before you start, you might want to check that you have the resources Pd +needs. The main things you need are the C compiler, X windows (including +the X development package for Pd to link against) and TK. If you're running +Redhat or Mandrake 7.x or up, I think these are all present by default. +The RedHat X client developer "RPM" package is called XFree86-devel. + +

You don't absolutely have to have the X server package running; you can run +Pd on the microprocessor in your refrigerator as long as it can connect to an X +server on another machine. + +

If you're running RedHat you might want to use RPM to install Pd. For +other linux distributions, download the "tar.gz" version and compile it. + +

Getting Pd as an RPM

+ +

Download Pd, perhaps from + + http://www.crca.ucsd.edu/~msp/software.html , +to a file such as "pd-0.33-0.i386.rpm". +Open a "shell" window, cd to +the directory containing the file, and type the command, +

+    rpm -i pd-0.33-0.i386.rpm
+

+ +

(substituting the real file name.) Then you should be able to type "pd" +to a shell and watch the Pd main window appear. + +

Getting Pd as a .tar.gz

+ +

+Download Pd, perhaps from + + http://www.crca.ucsd.edu/~msp/software.html , +to file such as "pd-linux-033.tar.gz". Open a "shell" +window, cd to +the directory containing the file, and type the command, +

+    zcat pd-linux-033.tar.gz | tar xf -
+

+which creates a directory named "pd". I do this from my home directory. +Next, compile it. "CD" to pd and read the INSTALL.txt, or else just cd +to "pd/src" and type + +
./configure +
make depend +
make + +

You can pass flags to "configure" to customize your compilation: + +

+    To enable ALSA 0.9x (the latest one), add "--enable-alsa".
+    To enable the older ALSA 0.5x, add "--enable-old-alsa". 
+    To enable Ritsch's RME 9652 driver, add --enable-rme".
+    To put Pd in /usr/bin instead of /usr/local/bin, add "--prefix=/bin".
+

+ +

After "make", just type "~/pd/bin/pd" to run pd. + +

Alternatively, as superuser, you can run "make install" after "make depend" +and then anyone on your system can just type "pd" to run it. + +

TK support trouble

+ +Some people have reported a problem with Pd findind the shared libraries, +"libtcl.so" and "libtk.so". I don't know what causes this, but apparently you +can fix it, as root, by linking /usr/lib/libtcl8.3.so to /usr/lib/libtcl.so and +similarly for tk: + +

+
+# cd /usr/lib
+# ln -s libtk8.3.so libtk.so
+# ln -s libtcl8.3.so libtcl.so
+
+

+ +

Testing audio and MIDI.

+ +

+Next try audio. We want to know whether audio output works, whether audio +input works, and whether they work simultaneously. First run "aumix" to +see audio input and output gains and which device is "recording". +Then test audio output by running +

+    pd -noadc
+

+and selecting "test audio and MIDI" from the "help" menu. You should see a +patch. Turn on the test tone and listen. Do the usual where's-the-signal +business. + +

+Then quit Pd and test audio input via +

+    pd -nodac
+

+Re-open the test patch and hit "meter"; look at the levels. 100 dB is a +hard clip; arrange gains so that the input signal tops out around 80 or 90, +but no higher. + +

Now see if your audio driver can do full duplex by typing "pd" with no +flags. If you see error messages involving /dev/dsp or /dev/dsp2, you're +probably not able to run audio in and out at the same time. If on the other +hand there's no complaint, and if the audio test patch does what you want, you +might wish to experiment with the "-audiobuffer" flag to see what values of +audio latency your audio system can handle. + +

Audio hardware in Linux

+ +

+Be forewarned: installing and testing audio and MIDI drivers in Linux can take +days or weeks. There apears to be no single place where you can get detailed +information on Linux audio. In addition to the information here, you should +see what's posted on Guenter's page, + + + http://gige.epy.co.at/ . + + +

+Depending on your hardware and software, you might or might not be able to +run "full duplex," i.e., use audio input and output at the same time. For +many applications it's important to be able to do this, but if by any chance +you don't need simultaneous input and output you will have much less trouble +than if you do. + +

+There are two widely-used driver sets, called "OSS" and "ALSA". OSS is +included in the standard Linux kernels since version 2.2. However, for some +audio cards you can find newer versions than are included in the kernel +releases. You can get ALSA from + + + http://www.alsa-project.org/ . + +

+(There is also a commercial version of the OSS drivers which costs $30 (slightly +more for certain audio cards.) Hit + + + http://www.opensound.com/ . + +These might be easier to use than the free OSS drivers, but I've never tried +them.) + +

ALSA is able to emulate OSS, so that you can usually run Pd using the +default "OSS" settings even if it's actually ALSA that's running. + +

Installing and configuring FREE OSS

+ +

+OSS is really a collection of loadable device drivers. The commands +for loading and unloading the drivers are "insmod" and "rmmod". +You can see if the audio drivers are +running using "lsmod" (as root.) If you see something like: +

+
+Module         Pages    Used by
+eepro100           3            1 (autoclean)
+opl3               3            0
+opl3sa2            1            0
+ad1848             4    [opl3sa2]       0
+mpu401             5    [opl3sa2]       0
+sound             15    [opl3 opl3sa2 ad1848 mpu401]    0
+soundcore          1    [sound] 6
+soundlow           1    [sound] 0
+aic7xxx           23            2
+
+

+then OSS is running, and if all you see is: +

+
+eepro100           3            1 (autoclean)
+aic7xxx           23            2
+
+

+then it isn't. You can turn OSS off by running "rmmod" repeatedly, starting +with "opl3" (or whatever) so as not to remove any module before you remove +all the modules that depend on it. In the above listing, "opl3*" is device +dependent and you might see different names. + +

+The file, "/etc/modules.conf" apparently controls which sound drivers are +started at boot time. The sndconfig program updates this file but you can +also change things manually, for instance to switch between two different sound +cards. In Redhat 6.x and earlier, the file is named "conf.modules." + +

Here is a modules.conf file for OSS: + +

+
+alias eth0 e100
+alias parport_lowlevel parport_pc
+alias char-major-81 bttv
+alias usb-controller usb-uhci
+alias sound-slot-0 i810_audio
+alias sound-slot-1 es1371
+
+

+ +Here the two sound cards are the (motherboard resident) i810 driver and an +ensoniq es1371. + +

In RedHat at least, the "sndconfig" program tries to automatically search +for your soundcard. Unfortunlately it only finds the "first" one which is +often not the one you want to use! + +

Under OSS, programs can stream sound using either +"block" or "stream" mode. Stream mode is the more modern and better of the +two, but the majority of drivers, even for new sound cards, only +support "block." Pd makes "block" the default. + +

ALSA (Advanced Linux Sound Architecture)

+ +

ALSA is newer, hence less stable and harder to use, than OSS. +Alsa comes in a "finished" version (0.5.x) and a +different, redesigned, "beta" version, 0.9. Installing ALSA can be tricky +and/or confusing. + +

As of version 0.33 Pd works with either 0.5.x or 0.9.x versions. +The RPM version of Pd is compiled for 0.9.x. If you're starting from the +".tar.gz" version, you have to "./configure --enable-alsa" to get it; see +the "INSTALL.txt" file in the installation. + +

By default, Pd uses OSS. If you are running ALSA, Pd will use ALSA's OSS +emulation. To make Pd use ALSA "natively", i.e., the way ALSA is designed +to be used, include the "-alsa" flag in the command line. + +

In ALSA, you can specify which sound card to use using the "-alsadev" +flag. So, for instance, "-alsadev 3" means your third card, counting from +one. You can also specify it the ALSA way: "-alsadev hw:3,0". + +

Which sound card?

+ +

+Here's a rundown on my experiences with sound cards so far. See +also the Pd mailing list archives. + +

opl3sa

+ +This is the old ISA "Yamaha" audio system. It comes on many Dell machines and +seems to offer reasonable consumer quality audio, at least under NT. I +believe the current version of OSS can get full duplex operation out of an +OPL3sa audio system. +This is an ISA ("plug and play" device and you have to deal with I/O +addresses and all that. + +

cs4232

+ +The 1999 vintage dual-processor Dell machines have "cs4232" audio, which I +couldn't get working. + +

es1370 (old Creative PCI128s; Ensoniq AudioPCI)

+ +

+The audio inputs and outputs on my PCI128 aren't clearly labelled and various +documents give them inconsistent names. On my card there are 4 stereo +mini jacks and a joystick port, in this order: + +

+joystick    black            green       red       blue
+            bidirectional    line-out    mic-in    line-in
+

+ +

It used to be possilbe to get quadraphonic audio in and out +of this card, but I haven't tried this in years. + +

Creative SBLive

+ +This seems to work fine either with ALSA or OSS as of Pd version 0.35; earlier +versions of Pd didn't see MIDI input under OSS (the driver's fault, not Pd's, +but I figured out a workaround.) + +

Sonorus Stud I/O

+ +This $1000 card is supposed to do multichannel digital I/O +in Linux, via a beta version of a commercial OSS driver ($40). +I don't know if anyone has used it with Pd. + +

RME 9652 (Hammerfall)

+ +

This is the best sound card out there; it costs around $500 and has 3 ADAT +I/O ports and one SPDIF. There is a "baby hammerfall" also, which I think is +the "9632." DO NOT CONFUSE THE 9652/9632 WITH OTHER RME BOARDS WHICH MIGHT +NOT WORK WITH PD. + +

Guenter Geiger has an OSS driver for Hammerfall for 2.4 kernels (such as +RedHat 7.1 and up). You have to download and compile it: + + + http://gige.xdv.org/pages/rme . + +

You must then run Pd using the "-32bit' flag, because this uses a +non-standard extension of OSS to 32 bit samples. + +

There's an older driver by Winfried Ritsch, invoked using the "-rme" +flag to Pd. This only works on 2.2 kernels, and you probably shouldn't +try it. It will probably be discontinued after Pd version 0.35. + +

Hammerfalls now have an ALSA driver; from what I hear +it won't work yet with Pd. I was unable to install the ALSA driver on the +two machines I tried ("no such device"). + +

MIDIMAN

+ +Midiman sells devices with between 4 and 12 analog channels in and out, for +which there are ALSA drivers. It seems to work fine with the old ALSA driver +(0.5). I'm running mine in Alsa 0.9 beta 10. The driver name is "ice1712". + +

Alsa provides an "envy24control" program (in "utils". You should run +this and check that your ice1712's sync source is internal if you have no +SPDIF input, or "SPDIF" if you do. I think the default is now "internal" +but don't take it for granted... + +

i810/i815

+ +In RedHat 7.0, motherboards with native i810 audio systems don't work in +full duplex (they crash linux). Either run Pd -noadc or else (better) install +ALSA. + +

Yamaha YMF724

+ +The OSS driver for this card appears not to support MIDI. I haven't +tried with ALSA. + +

ES1371

+ +In OSS, audio and MIDI seem both to work fine with this chipset. + +

3.4. Macintosh OSX

+ +Pd version 0.35 supports Macintosh OSX, although there are still various +problems. You can either download Pd with Mac OSX binaries, or just download +the sources and compile it yourself. + +

To install the binary OSX release:

+ +

First download and install TK for OSX +(http://sourceforge.net/projects/tcl/). Get a recent one compiled for +OSX, by chasing through "Mac OS X Tk Snapshots." I got +version 8.4a4-2, in a file named "MacOSXTk8.4a4-2.tar.gz ". Unpacking this +yields three directories: ./Applications/Wish Shell.app, +./Library/Frameworks/Tcl.framework, +and ./Library/Frameworks/Tk.framework. These must be moved, either to: +

+    ~/Applications/Wish Shell.app
+    ~/Library/Frameworks/Tcl.framework
+    ~/Library/Frameworks/Tk.framework
+

+or, if you wish to make them available to other users (or make it possible to +recompile Pd), in /Applications and /Library instead. + +

Then download and unpack the Pd binary distribution for OS X. This will +create a directory with a name like ~/Desktop/pd-0.35-test22. You can move +this elsewhere if you wish (to ~/pd, for example). To a shell window, type +either "~/Desktop/pd-0.35-test22/bin/pd" or, if you moved it as suggested, +"~/pd/bin/pd" . If you wish you can put the line, + +

+    alias pd ~/pd/bin/pd
+

+ +in the file, ~/.tcshrc, so that you can later just type "pd" to a shell. (The +shell only reads the ~/.tcshrc file onstartup, so this won't take effect in +any existing shells unless you specially type +

+    source ~/.tcshrc
+

+to them.) + +

In some cases you have to explicitly give "-soundindev" and "-soundoutdev" +flags for Pd to open audio correctly; "pd -listdev" should show you the +correct device numbers. + +

To get MIDI working, you have to do the Mac OSX magic to get a USB +MIDI interface installed. I've seen this done with Midisport devices and +I think you just download the OSX driver and follow directions. + +

On the machine I tried, it was necessary to type, + +

+    pd -midiindev 1 -midioutdev 2
+

+ +to get MIDI working. At the moment, using a midiman Midisport 2x2, I'm getting +several lines of debugging printout for each incoming MIDI message; it seems to +be the driver printing it out. I don't know how to turn this off. + +

To get Pd running at high priority, so that you'll get fewer skips in the +audio input and output, you must "renice" it. The easiest way to do this is +to make it SETUID and use the "-rt" flag. To do this, become root (you might +have to add a root account to do this) and type: + +

+    chown root ~ferguson/pd/bin/pd
+    chmod 4755 ~ferguson/pd/bin/pd
+

+(assuming your username is "ferguson"). + +

To compile your own Pd in OSX:

+ +Whether you've downloaded the source or the OSX binary distribution you can +always Pd for yourself, whether to make your own improvements, or possibly +so that you can get the newest version before it shows up compiled +for Mac OS X. + +

To be able to compile Pd, you must have installed Tcl/Tk + specifically in +/Applications/Wish Shell.app +and /Library/Frameworks/Tk.framework and /Library/Frameworks/Tcl.framework. + +You must also get the "h" files from XFree86 and put them in +/usr/X11R6/include. You can download just the H files from: +

+    http://www.crca.ucsd.edu/~msp/x.tgz
+

+(the individual files seem to have adequate copyright notices so that +I can just redistribute them.) + +Then, just as for linux, just unload pd-whatever.tar.gz into a directory +such as ~/pd-0.35-test17 , cd to pd-0.35-test17/src, type "./configure" +and "make". + +then type ~/pd-0.35-test17/bin/pd to a shell and enjoy! + + +

3.5. graphics rendering using GEM

+ +

+GEM, originally by Mark Danks but now supported by Iohannes Zmoelnig, is essentially an extension of Pd that allows you to do OpenGL programming +using a suite of "GEM objects" roughly parallel to the tilde objects built +into Pd for audio. Find out more from + Johannes's page. + + +

3.6. The Pd command line

+ +Pd is a "command line" program. The best way to run it is from your +"terminal emulator," "shell," or "MSDOS prompt." The command line is: + +

+
+    pd [options] [patches to open]
+
+

+ +although you may have to specify a path so your command interpreter can find +Pd (OS dependent.) Possible options include: + +

+
+audio configuration flags:
+-r            -- specify sample rate
+-inchannels ...  -- number of audio in channels (by device, like "2" or "16,8")
+-outchannels ... -- number of audio out channels (by device)
+-channels ...    -- specify both input and output channels
+-audiobuf     -- specify size of audio buffer in msec
+-blocksize    -- specify audio I/O block size in sample frames
+-sleepgrain   -- specify number of milliseconds to sleep when idle
+-nodac           -- suppress audio output
+-noadc           -- suppress audio input
+-noaudio         -- suppress audio input and output (-nosound is synonym) 
+-listdev          -- list audio and MIDI devices
+-audioindev ...  -- sound in device list; e.g., "2,1" for second and first
+-audiooutdev ... -- sound out device list, same as above 
+-audiodev ...    -- specify both -audioindev and -audiooutdev together
+
+(linux specific audio:)
+-frags        -- specify number of audio fragments (defeats audiobuf)
+-fragsize     -- specify log of fragment size ('blocksize' is better...)
+-stream          -- use stream mode audio (e.g., for es1370 audio cards)
+-alsa            -- use ALSA audio drivers
+-alsadev      -- ALSA device # (counting from 1) or name: default hw:0,0
+
+MIDI configuration flags:
+-midiindev ...   -- midi in device list; e.g., "1,3" for first and third
+-midioutdev ...  -- midi out device list, same format
+-mididev ...     -- specify -midioutdev and -midiindev together
+-nomidiin        -- suppress MIDI input
+-nomidiout       -- suppress MIDI output
+-nomidi          -- suppress MIDI input and output
+
+general flags:
+-path      -- add to file search path
+-open      -- open file(s) on startup
+-lib       -- load object library(s)
+-font         -- specify default font size in points
+-verbose         -- extra printout on startup and when searching for files
+-d            -- specify debug level
+-noloadbang      -- suppress all loadbangs
+-nogui           -- suppress starting the GUI
+-guicmd "cmd..." -- substitute another GUI program (e.g., rsh)
+-send "msg..."   -- send a message at startup (after patches are loaded)
+-rt or -realtime -- use real-time priority (needs root privilege)
+
+-frags        -- specify number of audio fragments (defeats audiobuf)
+-fragsize     -- specify log of fragment size ('blocksize' is better...)
+-blocksize    -- specify audio I/O block size in sample frames
+-stream          -- use stream mode audio (e.g., for es1370 audio cards)
+-alsa            -- use ALSA audio drivers
+-alsadev      -- ALSA device # (counting from 1) or name: default hw:0,0
+
+(MS Windows specific audio:)
+-resync           -- resynchronize audio (default if more than 2 channels)
+-noresync         -- never resynchronize audio I/O (default for stereo)
+-asio             -- use ASIO audio driver (and not the 'MMIO' default)
+
+MIDI configuration flags:
+-midiindev ...   -- midi in device list; e.g., "1,3" for first and third
+-midioutdev ...  -- midi out device list, same format
+-nomidiin        -- suppress MIDI input
+-nomidiout       -- suppress MIDI output
+-nomidi          -- suppress MIDI input and output
+
+general flags:
+-path      -- add to file search path
+-open      -- open file(s) on startup
+-lib       -- load object library(s)
+-font         -- specify default font size in points
+-verbose         -- extra printout on startup and when searching for files
+-d            -- specify debug level
+-noloadbang      -- suppress all loadbangs
+-nogui           -- suppress starting the GUI
+-guicmd "cmd..." -- substitute another GUI program (e.g., rsh)
+-send "msg..."   -- send a message at startup (after patches are loaded)
+-rt or -realtime -- use real-time priority (needs root privilege)
+
+

+ +Here are some details on some of the audio and MIDI options (but see also the +next section on file management.) + +

sample rate

+ +The sample rate controls Pd's logical sample rate which need not be that of +the audio input and output devices. If Pd's sample rate is wrong, time will +flow at the wrong rate and synthetic sounds will be transposed. If the output +and input devices are running at different rates, Pd will constantly drop frames +to re-sync them, which will sound bad. You can disable input or output if this +is a problem. + +

audio buffer size

+ +You can specify an audio buffer size in milliseconds, typically between 10 and +300, depending on how responsive your OS and drivers are. If this is set too +low there will be audio I/O errors ("data late"). The higher the value is, +on the other hand, the more throughput delay you will hear from the audio +and/or control inputs (MIDI, GUI) and the audio coming out. + +

In Linux and Windows, you can also specify the audio block size in sample +frames (but in Windows, this is only effective when using ASIO). + +

MIDI devices

+ +

You can specify multiple MIDI input and output devices. For example, +"pd -midiindev 3 -midioutdev 4,2" asks for the third MIDI input device and the +fourth and second MIDI output device. The "channel message" midi objects in Pd +such as notein or pgmout will take channels 1-16 to mean the first open MIDI +port, 17-32 the second one, and so on. The midiin, sysexin, midiout objects +give you a separate inlet to specify which of the open MIDI port numbers +you want. + +

In Linux, if you +ask for "pd -midioutdev 1" for instance, you get /dev/midi0 or /dev/midi00 +(or even /dev/midi). "-midioutdev 45" would be /dev/midi44. In NT, device +number 0 is the "MIDI mapper", which is the default MIDI device you selected +from the control panel; counting from one, the device numbers are card +numbers as listed by "pd -listdev." + +

3.7. dealing with files

+ +Pd has a search path feature; you specify the path on the command line +using the "-path" option. Paths may contain any number of files. If you +specify several files in a single "-path" option they're separated by colons +in unix or semicolons in NT. When Pd searches for an abstraction or an +"extern" it uses the path to try to find the necessary file. The "read" +messages to qlists and arrays (aka tables) work the same way. NO SPACES MAY +APPEAR ANYWHERE IN THE SEARCH PATH, e.g., "c:\my nonsense\goobers" won't +work. + +

Filenames in Pd are always separated by (unix-style) forward slashes, even +if you're on Windows (which uses backslashes). This is so that patches can be +ported more easily between operating systems. On the other hand, if you +specify a filename on the command line (as in "pd -path c:\pdlib") the file +separator should agree with the operating system.
+ +

If a filename in a patch has any "/" characters in it, the "path" is not +used; thus, "../sounds/sample1.wav" causes Pd only to look relative to the +directory containing the patch. (You may also invoke externs that way.) + +

As of version 0.35, there may be spaces in the path to Pd itself; also, +the "openpanel" and "savepanel" objects can handle spaces. But still not +the search path. + + + + + -- cgit v1.2.1