1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
<HTML>
<HEAD>
<TITLE>Pd Documentation 3</TITLE>
<meta http-equiv="Content-Type" content="text/html">
<link rel="stylesheet" type="text/css" href="pdmanual.css" media="screen">
</HEAD>
<BODY>
<H2>Pd Documentation chapter 3: Getting Pd to run</H2>
<P>
<A href="index.htm#s3"> back to table of contents </A>
<BR><BR>
</P>
<P>Pd runs under Irix, Microsoft Windows, Linux, and MacOS 10.2 (Jaguar).
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.
<P> Installation instructions are platform-specfic; the following four
sections
will describe what to do for various operating systems you might have.
In case of trouble also consult the Pd mailing list archive on
<A href="http://iem.kug.ac.at/mailinglists/pd-list/">
http://iem.kug.ac.at/mailinglists/pd-list/</A>
, which often has late-breaking news about configuration problems and solutions.
The rest of this section describes how to get audio and MIDI to work.
<H3> <A name=s1.0> 3.1. Audio and MIDI </A> </H3>
<P>
To test audio and MIDI, start Pd and select "test Audio and MIDI" from the
"Media" menu. You should see a window like this:
<CENTER><P>
<IMG src="fig11.1.png" ALT="test tone patch">
</P></CENTER>
<P> First, try to get Pd to play a sine wave over your speakers. The "TEST
TONE" control at top left turns this on and off. Normally, all the output
channels are turned on so that when you turn the tone on (to a soft -40 dB or a
louder -20 dB) you should get output on the first six of your output channels.
(If you have fewer than six output channnels open, the extra
channels aren't played; and if you have more, this particular patch won't
use them.)
<P> If there's anything wrong, the most likely outcome is that you will hear
nothing at all. This could be for any of at least three reasons: Pd might
have failed to open the audio device; the audio card's output volume might
be set to zero; or your audio system might not be set to amplify the computer
output.
<P> The number boxes labeled "AUDIO INPUT" show the levels of incoming
audio, in dB, with 100 being maximum. (Incoming signals may clip at
RMS levels below 100; for instance, a sinusoid clips at about 97 dB.)
Any DC present in the input (such as you get with cheap audio hardware)
will show up as level unless you turn on the "input hipass" toggle
at right; then the DC component is filtered out before metering.
<P> To test the quality of audio input and output, turn on "monitor"
(also at right) which causes the inputs to be played to the outputs at
unit gain. You should hear a faithful, non-distored copy of whatever is
sent through the patch.
<P> It is easy to get two copies of Pd running by accident; on most machines
only one at a time may be inputting and outputting sound. (Some copy of Pd
might have audio or MIDI devices open and prevent the copy you're trying to use
from getting access to them.) Having extra
copies of Pd around will also eat CPU cycles uselessly.
<P>
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 may be specified in Pd's command line flags or using the
"audio settings" dialog panel.
<P>
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.
<P> 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
audio latency in the command line or the "audio settings" dialog (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.
<P> In addition to the "test audio and MIDI" patch, the "Media" menu
contains items for controlling audio and MIDI settings. The first two
items, "Audio on" and "Audio off", open or close the audio devices and
start or stop Pd's audio computation.
<P> If there is a choice of
audio API to make, the Media menu will display them. (On Linux, they are
OSS, ALSA, and Portaudio; on Windows, you get MMIO and ASIO). More information
about the APIs appears in the sections below.
<P> Next is the "Audio settings..." menu item, which opens a dialog like this:
<CENTER><P>
<IMG src="fig11.2.png" ALT="audio settings dialog">
</P></CENTER>
The exact choices you get depend on the operating system and API. The sample
rate controls both audio output and input. The audio throughput delay is
the nominal amount of time, in milliseconds, that a sound coming into the
audio input will be delayed if it is copied through Pd straight to the
output. Naturally you would like this to be as small as possible, but,
depending on OS, API, and even the specific choice of audio hardware, there
will be a limit to how small you can make this. You can typically get
10 msec on linux (and lower still if you use special tricks), 30 msec on Mac
OSX, and 60 msec on Windows (but note that there might be ways that a
patient Windows user can reduce this).
<P> Next you get a choice of input and output device. If you want to open
more than one, hit "use multiple devices" and you'll be allowed up to 4
in and 4 out. Each audio device is 2 channels by default, but you may
specify more if your hardware supports it.
Other parameters may be tweaked using the command line; see under
<A href=#s4> preferences and startup options </A>.
<H6> MIDI </H6>
<A> 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.
<P> System exclusive MIDI message input and output is theoretically supported
in version 0.37 but does not work correctly on windows, even in 0.38.
<H3> <A name=s1.1> 3.2. Installing Pd in Microsoft Windows </A> </H3>
<P> Pd should work under any version of Windows since 95. You can download as
a self-extracting archive (a ".exe" file). Run this and select a destination
directory when prompted, such as "\pd" or "Program Files\pd".
<P> If for example you put Pd in "C:Program Files\pd", the executable program
will be "C:Program Files\pd\bin\pd". You can simply adjust your path to
include C:\pd\bin and then invoke "pd" in a command prompt window. You can also
make a shortcut to the executable program (left-click on it and drag to the
desktop, for example.)
<P> 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" (locally) to intercommunicate.
<H4> Audio in Microsoft Windows </H4>
<P>
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. You can modify the Pd shortcut (or batch file) to
set these, or else use the "startup" dialog (file menu) to specify
startup arguments.
<P>
Alternatively, (and especially when just starting out) you can experiment
with different audio configurations using the "audio settings"
item in the Media menu.
<P>
You can list and
choose MIDI devices in the same way as audio; note that, by default, MIDI
input is disabled in Windows (because it's possible to hang up some MIDI
devices if Pd exits unexpectedly).
<P>
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). The "first edition" used to crash
occasionally; this might be fixed in the "second edition".
<H4> ASIO </H4>
<P> 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.
<H3> <A name=s1.2> 3.3. Installing Pd in Linux </A> </H3>
<P> 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. (If not, you can read the Pd mailing list archives for
recent problems; if you have found a new problem you're welcome to post it
to the list.)
<P> If you're running RedHat or Mandrake you might want to use RPM to install
Pd. For other linux distributions, download the "tar.gz" version and compile
Pd.
<H4> Getting Pd as an RPM </H4>
<P> Download Pd, perhaps from
<a href="http://www.crca.ucsd.edu/~msp/software.html">
http://www.crca.ucsd.edu/~msp/software.html</A> ,
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,
<PRE>
rpm -i pd-0.33-0.i386.rpm
</PRE>
<P> (substituting the real file name.) Then you should be able to type "pd"
to a shell and watch the Pd main window appear.
<H4> Getting Pd as a .tar.gz </H4>
<P> 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.
<P>
Download Pd, perhaps from
<a href="http://www.crca.ucsd.edu/~msp/software.html">
http://www.crca.ucsd.edu/~msp/software.html</A> ,
to file such as "pd-linux-033.tar.gz". Open a "shell"
window, cd to
the directory containing the file, and type the command,
<PRE>
tar xzf pd-linux-033.tar.gz
</PRE>
<P>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
<P>
<BR> ./configure
<BR> make depend
<BR> make
</P>
<P> You can pass flags to "configure" to customize your compilation:
<PRE>
To enable debugging (and losing code optimization) add "--enable-debug".
To use Portaudio version 19 (experimental), add "--enable-portaudio".
To put Pd in /usr/bin instead of /usr/local/bin, add "--prefix=/bin".
</PRE>
Alsa and Jack support should auto-configure, but "--enable-alsa" od
"--enable-jack" will force their inclusion.
<P> After "make", just type "~/pd/bin/pd" to run pd.
<P> Alternatively, as superuser, you can run "make install" after "make depend"
and then anyone on your system can just type "pd" to run it.
<H4> Testing audio and MIDI. </H4>
<P>
Next try audio. We want to know whether audio output works, whether audio
input works, and whether they work simultaneously. First run "aumix" (or
any newer audio mixer app) to
check audio input and output gains and learn which input (mic; line;
etc.) is "recording".
Then test audio output by running
<PRE>
pd -noadc
</PRE>
<P>and selecting "test audio and MIDI" from the "Media" menu. You should see
a patch. Turn on the test tone and listen. Do the usual where's-the-signal
business.
<P>
Then quit Pd and test audio input via
<PRE>
pd -nodac
</PRE>
<P>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.
<P> 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.
<H3> Audio hardware in Linux </H3>
<P>
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. One good source of information lives at:
<A href=http://www.djcj.org/LAU/guide/index.php>
http://www.djcj.org/LAU/guide/index.php </A>.
<P>
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
<a href="http://www.alsa-project.org/">
http://www.alsa-project.org/</A> .
<P> 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.
ALSA is newer, hence less stable and harder to use, than OSS.
Installing ALSA can be tricky and/or confusing.
<P> 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 or bang on the "media"
menu items.
<P> You can add ALSA devices by name on the Pd command line:
<PRE>
pd -alsaadd loupgarou
</PRE>
instructs Pd to offer the 'loupgarou' audio device in the Audio Settings panel.
<H4> Experiences with particular soudcards </H4>
<P>
Here are some of my own experiences with sound cards so far. See
also the Pd mailing list archives.
<H6> RME 9652 (Hammerfall) </H6>
<P> 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.
<P> The easiest way to use
Hammerfall boards in Pd is via ALSA and jack; but you can use ALSA alone:
<PRE>
pd -alsa -channels 26
</PRE>
works for me. If you don't specify the number of channels correctly Pd crashes.
<H6> MIDIMAN </H6>
<P>Midiman sells PCI devices (delta 44, 66, 1010, and 1010LT)
with between 4 and 10 channels in and out, for
which there are ALSA drivers. These are also very good, and they are a
bit cheaper than Hammerfalls. The driver name is "ice1712".
<P> 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...
<H6> warning about i810/i815 drivers...</H6>
<P>As of RedHat 7.0, motherboards with native i810 audio systems didn't work in
full duplex (they crashed linux). Either run Pd -noadc or else (better)
install ALSA. This ought to be fixed by now...
<H3> <A name="s1.3"> 3.4. Installing Pd in Macintosh OSX </A> </H3>
<P>Pd version 0.35 and up support Macintosh OSX. You need the OSX Jaguar
distribution (10.2) or later.
<P> To install Pd you can always just download the sources and compile them
yourself, or (easier) just download the Mac binary from the download page:
<A href="http://crca.ucsd.edu/~msp/software.html">
http://crca.ucsd.edu/~msp/software.html</A>.
This is in the form of a compressed Tar archive; just click on it and the Max
will extract the Pd application. Open this and you should be running.
<P> The package by Hans-Christoph Steiner, on
<A href="http://at.or.at/hans/pd/installers.html">
http://at.or.at/hans/pd/installers.html</A>,
has many updates and extensions
which are not included in the original Pd distribution. Download this and
follow the (simple) instructions found there.
</P>
<H4> To install on OSX from source: </H4>
<P>
Whether you've downloaded the source or the "package" you can
always compile 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.
<P> 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.
<P> First download and install TK for OSX. I get it from:
<A href=http://tcltkaqua.sourceforge.net/>
http://tcltkaqua.sourceforge.net/. </A>
<P> Then, just as for linux, just unload pd-whatever.tar.gz into a directory
such as ~/pd-0.36-0, cd to pd-0.36-0/src, type "./configure"
and "make". Then type ~/pd-0.36-0/bin/pd to a shell and enjoy!
<P> If you wish you can put a line such as,
<pre>
alias pd ~/pd/bin/pd
</pre>
<P>in the file, ~/.tcshrc, so that you can later just type "pd" to a shell.
(The
shell only reads the ~/.tcshrc file on startup, so this won't take effect in
any existing shells unless you specially type
<pre>
source ~/.tcshrc
</pre>
<P>to them.)
<P> Follow the general directions above for testing audio and/or MIDI
as needed.
<P> 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.
<H3> <A name=s1.4> 3.5. Installing Pd in IRIX (SGI machines) </A> </H3>
<P> (NOTE: as of release 0.35 I haven't had an IRIX machine to compile
Pd on. Soeren Bovbjerg has kindly compiled 0.35 and 0.36 for IRIX;
you can find these at
<A href="http://www.cvmt.dk/~sb/"> http://www.cvmt.dk/~sb/ </A>.)
<P> 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".
<P>
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."
<P> 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.
<P>
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.
<P>
The simplest way to invoke Pd is to
make an alias in your ".cshrc" file (assuming you use the "c" shell) such as:
</P>
<PRE>
alias pd ~/pd/bin/pd
</PRE>
<P>(assuming your Pd distribution landed in ~, for example).
<P>
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.)
<P>
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.
<P> 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.
<H4> Audio and MIDI in IRIX </H4>
<P>
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.
<P>
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
<PRE>
startmidi -d /dev/ttyd2
</PRE>
<P>to get port 2 speaking MIDI, and
<PRE>
stopmidi
</PRE>
<P>to stop it. You can test whether MIDI is configured by typing,
<PRE>
ps -dafe | grep midi
</PRE>
<P>and looking for "startmidi" processes.
<P>
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.
<P>
The O2 apparently has RS232 ports, not RS422. I think SGI's web site says
something about how to deal with this.
<H3> <A name=s4> 3.6. Preferences and startup options </A> </H3>
<P> Pd's behavior may be customized to instruct it where to find files, which
audio devices to open, what font size to use, and so on. Most of
these may also be changed using the various dialogs you can open from Pd's
menus. Others take effect only when Pd starts up; some of these appear
on the ``startup" dialog and some of them, too cranky to put in a GUI, must
be typed as <I> command line arguments </I>.
<P> In addition to the Audio and MIDI settings (see
<A href="#s1.0"> Audio and MIDI </A>), you can customize font size (from the
``edit" menu), directories to search for files (see
<A href="#s5"> How Pd searches for files </A>), and additional startup
parameters described below.
<P> All of these settings may be saved automatically between Pd sessions.
It is also possible to specify settings directly via the <I> command
line </I>. (A third mechanism, using configuration files, is deprecated and
isn't described here.) The Pd command line is described in the next
section. Command line settings, if given, each override the corresponding
setting that was saved from Pd.
<P> The startup settings (i.e., those that take effect only when Pd is started)
are controlled using the ``startup..." dialog from the File menu. The
dialog appears as follows:
<CENTER><P>
<IMG src="fig11.3.png" ALT="startup dialog">
</P></CENTER>
The slots at top each specify a binary ``library" for Pd to load on startup.
These may be for Gem, pdp, zexy, iemlib, cyclone, and so on. Typically, a
single binary object (an ``extern") is left for Pd to load automatically;
startup library loading is appropriate for collections of many objects
specified by a single binary library.
<P> The ``defeat real-time scheduling" contol, if enabled, makes Pd run without
its usual effort to become a real-time process (whatever this means in the
operating system you are using.) In Unix, Pd must usually be setuid to allow
real-time scheduling at all.
<P> The ``startup flags" allow you to add to Pd's command line on startup. This
is specified as described below, except that the initial word, ``pd", is
understood. For example, putting ``-rt" in this field sets real-time
scheduling; ``-sleepgrain 1" sets the sleep grain to 1 (see under MIDI below),
and typing "-rt -sleepgrain 1" does both.
<P> You may save the current settings for future Pd sessions with the
``save all settings" button; this saves not only the path but all other
settings as well.
<H6> Command line arguments </A> </H3>
<P>Pd may be run as a "command line" program from your "terminal emulator,"
"shell," or "MSDOS prompt." In Windows, if Pd is started using a "shortcut"
it is also run from a command line which you can edit using the ``properties"
dialog for the shortcut. In any operating system, Pd can be called from a
script (called a <I> batch file </I> on Windows or a <I> shell script </I>
on OSX or unix). The command line is just a line of text, which should be
of the form:
<PRE>
pd [options] [patches to open]
</PRE>
<P>although you may have to specify a path (such as "~/pd/bin/pd" or
"C:\program files\pd\bin\pd") so your command interpreter can find
Pd. Possible options include:
<PRE>
audio configuration flags:
-r <n> -- specify sample rate
-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
-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 <n> -- specify size of audio I/O buffer in msec
-blocksize <n> -- specify audio I/O block size in sample frames
-sleepgrain <n> -- 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
(linux specific audio:)
-frags <n> -- specify number of audio fragments (defeats audiobuf)
-fragsize <n> -- specify log of fragment size ('blocksize' is better...)
-oss -- use ALSA audio drivers
-alsa -- use ALSA audio drivers
-pa -- use portaudio (experimental version 19)
-alsadev <n> ----- obsolete: use -audiodev
-32bit ---- (probably obsolete) -- use 32 bit OSS extension
(Windows specific audio:)
-mmio -- use MMIO drivers and API
-asio -- use ASIO drivers and API
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 <path> -- add to file search path
-nostdpath -- don't search standard ("extra") directory
-stdpath -- search standard directory (true by default)
-helppath <path> -- add to help search path
-open <file> -- open file(s) on startup
-lib <file> -- load object library(s)
-font <n> -- specify default font size in points
-verbose -- extra printout on startup and when searching for files
-version -- don't run Pd; just print out which version it is
-d <n> -- specify debug level
-noloadbang -- suppress all loadbangs
-stderr -- send printout to standard error instead of GUI
-nogui -- suppress starting the GUI
-guiport <n> -- connect to pre-existing GUI over port 'n'
-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)
-nrt -- don't use real-time priority
</PRE>
<P>Here are some details on some of the audio, MIDI, and scheduler options (but
see also the next section on file management.)
<H4> multiple devices. </H4>
<P> 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.
<P> Audio device selection is similar, except that you can also specify
channels by device: "-audioindev 1,3 -inchannels 2,8" will try to open device 1
(2 channels) and device 3 (8 channels.)
<H4> sample rate. </H4>
<P>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.
<H4> audio buffer size and block size </H4>
<P>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.
<P> You can also specify the audio block size in sample frames. This is 64 by
default (except for MMIO for which it's 256), and may be 64, 128, or 256.
<H4> MIDI and sleepgrain</H4>
<P> 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."
<P> The "sleepgrain" controls how long (in milliseconds) Pd sleeps between
periods of computation. This is normally the audio buffer divided by 4, but
no less than 0.1 and no more than 5. On most OSes, ingoing and outgoing MIDI
is quantized to this value, so if you care about MIDI timing, reduce this to 1
or less.
<H3> <A name="s5"> 3.7. How Pd searches for files </A> </H3>
<P>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.
<P> You can see and edit the path while Pd is running using the "path..."
item in the "File" menu:
<CENTER><P>
<IMG src="fig11.4.png" ALT="startup dialog">
</P></CENTER>
<P> The path must be correctly set before you load
a patch or it may fail to find abstractions, etc., that are needed to
construct the patch. 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) do this too.
<P> If ``use standard extensions" is enabled, the usual ``extras" directory
is also searched. This contains standard external objects like ``expr" and
``fiddle", and perhaps much more depending on the distribution of Pd
you're using.
<P> You may save the current settings for future Pd sessions with the
``save all settings" button; this saves not only the path but all other
settings as well.
<P> Path entries may be relative to the patch directory; for instance,
if your path has an item, "../sound", and your patch is in "my stuff/all mine",
then Pd will look in "my stuff/sound". Spaces should be OK in the path to
the patch, but not in the path entry (../sound) itself. This is useful if
you have a patch and supporting files (even a supporting snapshot of pd)
that you want to distribute or carry around together.
<P> Regardless of path, Pd should look first in the directory containing
the patch before searching down the path. Pd does not automatically look
in the <I> current directory </I> however; to enable that, include ``." in
the path. The ``extra" directory, if enabled, is searched last.
<P> 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. <BR>
<P> If a filename specified 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.
<P> As of version 0.35, there may be spaces in the path to Pd itself; also,
the "openpanel" and "savepanel" objects can handle spaces. Spaces in the
path should work as of version 0.38.
</BODY>
</HTML>
|
