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The first basic idea of the glitch-free playback model (a better, less marketingy name is probably timer-based audio scheduling which is the term I internally use in the PA codebase) is to no longer depend on sound card interrupts to schedule audio but use system timers instead. System timers are far more flexible then the fragment-based sound card timers. They can be reconfigured at any time, and have a granularity that is independant from any buffer metrics of the sound card. The second basic idea is to use playback buffers that are as large as possible, up to a limit of 2s or 5s. The third basic idea is to allow rewriting of the hardware buffer at any time. This allows instant reaction on user-input (i.e. pause/seek requests in your music player, or instant event sounds) although the huge latency imposed by the hardware playback buffer would suggest otherwise.

whenever a news site or blog runs a story about one of these alternative controllers, the naysayers crawl out of the slime and start whining “there’s no way I could ever learn to play that”, “it has too many buttons and it scares me”, “I invested in keyboard lessons and I’m not throwing away all that investment”, etc etc. The simple fact that the Jankó design was MEANT TO BE EASIER TO PLAY….they don’t care. Musicians are so conservative it’s disgusting.

XML-RPC XML-RPC is the second request format supported by Flickr. XML-RPC uses HTTP as the transport and XML for encoding. In XML-RPC, the method parameters are wrapped in a XML document and POST-ed to the XML-RPC endpoint, in this case http://api.flickr.com/services/xmlrpc/. A XML-RPC request will have this format: <methodCall> <methodName>flickr.test.echo</methodName> <params> <param> <value> <struct> <member> <name>api_key</name> <value><string>..your API key..</string></value> </member> </struct> </value> </param> </params> </methodCall> If the method takes more than one parameter, you will have to repeat the <member> structure for each parameter; you can find detailed instructions regarding the packaging of complex datatypes at www.xmlrpc.com. Here is how to implement this call in Actionscript: var request:XML; var response:XML; request=new XML(); response = new XML(); response.onLoad=function(success:Boolean){ trace(success); trace(this.toString()); } request.xmlDecl = '<?xml version="1.0"?>'; request.parseXML("<methodCall><methodName>flickr.test.echo</methodName><params> <param><value><struct><member><name>api_key</name><value>..your API key..</value></member></struct></value></param></params></methodCall>"); request.sendAndLoad("http://api.flickr.com/services/xmlrpc/", response); Since this is a HTTP POST operation, I have to use the sendAndLoad method of the XML object. Developer Matt Shaw is behind an open source project that provides a XML-RPC library for Actionscript; an introduction can be found at http://xmlrpcflash.mattism.com/, or you can download the library (more details can be found here). Using this library, the call to the echo function shown above would look like this: import com.mattism.http.xmlrpc.Connection; import com.mattism.http.xmlrpc.ConnectionImpl; onLoadListing = function( response:Array ){ trace("Found the following objects:"); var i:Number; for (i=0; i<response.length; i++){ trace(i+". "+url+response[i]); } }; var url:String = "http://api.flickr.com/services/xmlrpc/"; var c:Connection = new ConnectionImpl(); c.setUrl(url); c.onLoad = onLoadListing; c.addParam( { api_key:'...your API key...' }, "struct"); c.call("flickr.test.echo");

from SimpleXMLRPCServer import SimpleXMLRPCServer,SimpleXMLRPCRequestHandler class ExtendedXMLRPCRequestHandler(SimpleXMLRPCRequestHandler): def do_GET(self): #only allow a request for the crossdomain file #this can be changed to support GETs of any file if needed if self.path != '/crossdomain.xml': self.send_response(403) self.log_request(403) return #open the crossdomain file and read its contents f = file('crossdomain.xml', 'r') msg = f.read() f.close() #write the data to the socket along with valid HTTP headers res = 'HTTP/1.0 200 OK\r\nDate: %s\r\n\r\n%s' % \ (self.date_time_string(),msg) self.wfile.write(res) self.log_request(200) class EchoClass: def echo(self, data): return data #create an instance of the class s = EchoClass() #create the server on localhost server = SimpleXMLRPCServer(('', 8000), ExtendedXMLRPCRequestHandler) #register the instance as a web service server.register_instance(s) #start accepting requests server.serve_forever()