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diff --git a/pd/portaudio/docs/pa_impl_guide.html b/pd/portaudio/docs/pa_impl_guide.html deleted file mode 100644 index 50abc304..00000000 --- a/pd/portaudio/docs/pa_impl_guide.html +++ /dev/null @@ -1,197 +0,0 @@ -<!doctype html public "-//w3c//dtd html 4.0 transitional//en"> -<html> -<head> - <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> - <meta name="GENERATOR" content="Mozilla/4.79 [en] (Windows NT 5.0; U) [Netscape]"> - <meta name="Author" content="Phil Burk"> - <meta name="Description" content="Internal docs. How a stream is started or stopped."> - <meta name="KeyWords" content="audio, tutorial, library, portable, open-source, DirectSound,sound, music, JSyn, synthesis,"> - <title>PortAudio Implementation - Start/Stop</title> -</head> -<body> - -<center><table COLS=1 WIDTH="100%" BGCOLOR="#FADA7A" > -<tr> -<td> -<center> -<h1> -<a href="http://www.portaudio.com">PortAudio</a> Implementation Guide</h1></center> -</td> -</tr> -</table></center> - -<p>This document describes how to implement the PortAudio API on a new -computer platform. Implementing PortAudio on a new platform, makes it possible -to port many existing audio applications to that platform. -<p>By Phil Burk -<br>Copyright 2000 Phil Burk and Ross Bencina -<p>Note that the license says: <b>"Any person wishing to distribute modifications -to the Software is requested to send the modifications to the original -developer so that they can be incorporated into the canonical version."</b>. -So when you have finished a new implementation, please send it back to -us at "<a href="http://www.portaudio.com">http://www.portaudio.com</a>" -so that we can make it available for other users. Thank you! -<h2> -Download the Latest PortAudio Implementation</h2> -Always start with the latest implementation available at "<a href="http://www.portaudio.com">http://www.portaudio.com</a>". -Look for the nightly snapshot under the CVS section. -<h2> -Select an Existing Implementation as a Basis</h2> -The fastest way to get started is to take an existing implementation and -translate it for your new platform. Choose an implementation whose architecture -is as close as possible to your target. -<ul> -<li> -DirectSound Implementation - pa_win_ds - Uses a timer callback for the -background "thread". Polls a circular buffer and writes blocks of data -to keep it full.</li> - -<li> -Windows MME - pa_win_wmme - Spawns an actual Win32 thread. Writes blocks -of data to the HW device and waits for events that signal buffer completion.</li> - -<li> -Linux OSS - pa_linux - Spawns a real thread that writes to the "/dev/dsp" -stream using blocking I/O calls.</li> -</ul> -When you write a new implementation, you will be using some code that is -in common with all implementations. This code is in the folder "pa_common". -It provides various functions such as parameter checking, error code to -text conversion, sample format conversion, clipping and dithering, etc. -<p>The code that you write will go into a separate folder called "pa_{os}_{api}". -For example, code specific to the DirectSound interface for Windows goes -in "pa_win_ds". -<h2> -Read Docs and Code</h2> -Famialiarize yourself with the system by reading the documentation provided. -here is a suggested order: -<ol> -<li> -User Programming <a href="pa_tutorial.html">Tutorial</a></li> - -<li> -Header file "pa_common/portaudio.h" which defines API.</li> - -<li> -Header file "pa_common/pa_host.h" for host dependant code. This definces -the routine you will need to provide.</li> - -<li> -Shared code in "pa_common/pa_lib.c".</li> - -<li> -Docs on Implementation of <a href="pa_impl_startstop.html">Start/Stop</a> -code.</li> -</ol> - -<h2> -Implement Output to Default Device</h2> -Now we are ready to crank some code. For instant gratification, let's try -to play a sine wave. -<ol> -<li> -Link the test program "pa_tests/patest_sine.c" with the file "pa_lib.c" -and the implementation specific file you are creating.</li> - -<li> -For now, just stub out the device query code and the audio input code.</li> - -<li> -Modify PaHost_OpenStream() to open your default target device and get everything -setup.</li> - -<li> -Modify PaHost_StartOutput() to start playing audio.</li> - -<li> -Modify PaHost_StopOutput() to stop audio.</li> - -<li> -Modify PaHost_CloseStream() to clean up. Free all memory that you allocated -in PaHost_OpenStream().</li> - -<li> -Keep cranking until you can play a sine wave using "patest_sine.c".</li> - -<li> -Once that works, try "patest_pink.c", "patest_clip.c", "patest_sine8.c".</li> - -<li> -To test your Open and Close code, try "patest_many.c".</li> - -<li> -Now test to make sure that the three modes of stopping are properly supported -by running "patest_stop.c".</li> - -<li> -Test your implementation of time stamping with "patest_sync.c".</li> -</ol> - -<h2> -Implement Device Queries</h2> -Now that output is working, lets implement the code for querying what devices -are available to the user. Run "pa_tests/pa_devs.c". It should print all -of the devices available and their characteristics. -<h2> -Implement Input</h2> -Implement audio input and test it with: -<ol> -<li> -patest_record.c - record in half duplex, play back as recorded.</li> - -<li> -patest_wire.c - full duplex, copies input to output. Note that some HW -may not support full duplex.</li> - -<li> -patest_fuzz.c - plug in your guitar and get a feel for why latency is an -important issue in computer music.</li> - -<li> -paqa_devs.c - try to open every device and use it with every possible format</li> -</ol> - -<h2> -Debugging Tools</h2> -You generally cannot use printf() calls to debug real-time processes because -they disturb the timing. Also calling printf() from your background thread -or interrupt could crash the machine. So PA includes a tool for capturing -events and storing the information while it is running. It then prints -the events when Pa_Terminate() is called. -<ol> -<li> -To enable trace mode, change TRACE_REALTIME_EVENTS in "pa_common/pa_trace.h" -from a (0) to a (1).</li> - -<li> -Link with "pa_common/pa_trace.c".</li> - -<li> -Add trace messages to your code by calling:</li> - -<br><tt> void AddTraceMessage( char *msg, int data );</tt> -<br><tt>for example</tt> -<br><tt> AddTraceMessage("Pa_TimeSlice: past_NumCallbacks ", -past->past_NumCallbacks );</tt> -<li> -Run your program. You will get a dump of events at the end.</li> - -<li> -You can leave the trace messages in your code. They will turn to NOOPs -when you change TRACE_REALTIME_EVENTS back to (0).</li> -</ol> - -<h2> -Delivery</h2> -Please send your new code along with notes on the implementation back to -us at "<a href="http://www.portaudio.com">http://www.portaudio.com</a>". -We will review the implementation and post it with your name. If you had -to make any modifications to the code in "pa_common" or "pa_tests" <b>please</b> -send us those modifications and your notes. We will try to merge your changes -so that the "pa_common" code works with <b>all</b> implementations. -<p>If you have suggestions for how to make future implementations easier, -please let us know. -<br>THANKS! -<br> -</body> -</html> |