I wrote a small WPF app to route MIDI in to MIDI out and send bank and program change messages to my older synth module. I decided to use DryWetMidi for the MIDI I/O, which is very easy to use. While reading the docs for DryWetMidi, I noticed it had support for high precision timing. I'm wondering if these timers could be used to create arpeggiators and other such MIDI effects. Would this be as simple as processing MIDI data in the timer callback? What would be the best way to achieve something like this using this API?
I'm the author of DryWetMIDI (DWM). Yes, you can use HighPrecisionTickGenerator separately from other DWM API:
var tickGenerator = new HighPrecisionTickGenerator();
tickGenerator.TickGenerated += OnTickGenerated;
tickGenerator.TryStart(TimeSpan.FromMilliseconds(1));
...
private void OnTickGenerated(object sender, EventArgs e)
{
// ...
}
Related
getUserMedia(constrains).then(stream => {
var recorder = new MediaRecorder(stream)
})
recorder.start()
recorder.pause()
// get new stream getUserMedia(constrains_new)
// how to update recorder stream here?
recorder.resume()
Is it possible? I've try to create MediaStream and use addTrack and removeTrack methods to change stream tracks but no success (recorder stops when I try to resume it with updated stream)
Any ideas?
The short answer is no, it's not possible. The MediaStream recording spec explicitly describes this behavior: https://w3c.github.io/mediacapture-record/#dom-mediarecorder-start. It's bullet point 15.3 of that algorithm which says "If at any point, a track is added to or removed from stream’s track set, the UA MUST immediately stop gathering data ...".
But in case you only want to record audio you can probably use an AudioContext to proxy your streams. Create a MediaStreamAudioDestinationNode and use the stream that it provides for recording. Then you can feed your streams with MediaStreamAudioSourceNodes and/or MediaStreamTrackAudioSourceNodes into the audio graph and mix them in any way you desire.
Last but not least there are currently plans to add the functionality you are looking for to the spec. Maybe you just have to wait a bit. Or maybe a bit longer depending on the browser you are using. :-)
https://github.com/w3c/mediacapture-record/issues/167
https://github.com/w3c/mediacapture-record/pull/186
I currently am using Max/MSP to create an interactive system between lights and sound.
I am using Philips hue lighting which I have hooked up to Max/MSP and now I am wanting to trigger an increase in brightness/saturation on the input of a note from a Midi instrument. Does anyone have any ideas how this might be accomplished?
I have built this.
I used the shell object. And then feed an array of parameters into it via a javascipt file with the HUE API. There is a lag time of 1/6 of a second between commands.
Javascript file:
inlets=1;
outlets=1;
var bridge="192.168.0.100";
var hash="newdeveloper";
var bulb= 1;
var brt= 200;
var satn= 250;
var hcolor= 10000;
var bulb=1;
function list(bulb,hcolor,brt,satn,tran) {
execute('PUT','http://'+bridge+'/api/'+hash+'/lights/'+bulb+'/state', '"{\\\"on\\\":true,\\\"hue\\\":'+hcolor+', \\\"bri\\\":'+brt+',\\\"sat\\\":'+satn+',\\\"transitiontime\\\":'+tran+'}"');
}
function execute($method,$url,$message){
outlet(0,"curl --request",$method,"--data",$message,$url);
}
To control Philips Hue you need to issue calls to a restful http based api, like so: http://www.developers.meethue.com/documentation/core-concepts, using the [jweb] or [maxweb] objects: https://cycling74.com/forums/topic/making-rest-call-from-max-6-and-saving-the-return/
Generally however, to control lights you use DMX, the standard protocol for professional lighting control. Here is a somewhat lengthy post on the topic: https://cycling74.com/forums/topic/controlling-video-and-lighting-with-max/, scroll down to my post from APRIL 11, 2014 | 3:42 AM.
To change the bri/sat of your lights is explained in the following link (Registration/Login required)
http://www.developers.meethue.com/documentation/lights-api#16_set_light_state
You will need to know the IP Address of your hue hue bridge which is explained here: http://www.developers.meethue.com/documentation/getting-started and a valid username.
Also bear in mind the performance limitations. As a general rule you can send up to 10 lightstate commands per second. I would recommend having a 100ms gap between each one, to prevent flooding the bridge (and losing commands).
Are you interested in finding out details of who to map this data from a MIDI input to the phillips HUE lights within max? or are you already familiar with Max.
Using Tommy b's javascript (which you could put into a js object), You could for example scale the MIDI messages you want to use using midiin and borax objects and map them to the outputs you want using the scale object. Karlheinz Essl's RTC library is a good place to start with algorithmic composition if you want to transform the data at all http://www.essl.at/software.html
+1 for DMX light control via Max. There are lots of good max-to-dmx tutorials and USB-DMX hardware is getting pretty cheap. However, as someone who previously believed in dragging a bunch of computer equipment on stage just to control a light or two with an instrument, I'd recommend researching and purchasing a simple one channel "color organ" circuit kit (e.g., Velleman MK 110). Controlling a 120/240V light bulb via audio is easier than you might think; a computer for this type of application is usually overkill. Keep it simple and good luck!
I need to detect when the current playing audio/video is paused. I cannot find anything for 1.0. My app is a bit complex but here is condensed code
/* This function is called when the pipeline changes states. We use it to
* keep track of the current state. */
static void state_changed_cb(GstBus *bus, GstMessage *msg, CustomData *data)
{
GstState old_state, new_state, pending_state;
gst_message_parse_state_changed(msg, &old_state, &new_state, &pending_state);
if(GST_MESSAGE_SRC(msg) == GST_OBJECT(data->playbin))
{
g_print("State set to %s\n", gst_element_state_get_name(new_state));
}
}
gst_init(&wxTheApp->argc, &argv);
m_playbin = gst_element_factory_make("playbin", "playbin");
if(!m_playbin)
{
g_printerr("Not all elements could be created.\n");
exit(1);
}
CustomData* data = new CustomData(xid, m_playbin);
GstBus *bus = gst_element_get_bus(m_playbin);
gst_bus_set_sync_handler(bus, (GstBusSyncHandler) create_window, data, NULL);//here I do video overly stuffs
g_signal_connect (G_OBJECT (bus), "message::state-changed", (GCallback)state_changed_cb, &data);
What do I do wrong? I cannot find working example on connecting such events on Gstreamer 1.0 and 0.x seems a bit different than 1.0 so the vast exaples there don't help
UPDATE
I have found a way to get signals. I run wxWidgets timer with 500ms time span and each time timer fires I call
GstMessage* msg = gst_bus_pop(m_bus);
if(msg!=NULL)
{
g_print ("New Message -- %s\n", gst_message_type_get_name(msg->type));
}
Now I get a lot of 'state-change' messages. Still I want to know if that message is for Pause or Stop or Play or End of Media (I mean way to differentiate which message is this) so that I can notify the UI.
So while I get signals now, the basic problem, to get specific signals, remains unsolved.
You have to call gst_bus_add_signal_watch() (like in 0.10) to enable emission of the signals. Without that you can only use the other ways to get notified about GstMessages on that bus.
Also just to be sure, you need a running GLib main loop on the default main context for this to work. Otherwise you need to do things a bit different.
For the updated question:
Check the documentation: gst_message_parse_state_changed() can be used to parse the old, new and pending state from the message. This is also still the same as in 0.10. From the application point of view, and conceptionally nothing much has changed really between 0.10 and 1.0
Also you shouldn't do this timeout-waiting as it will block your wxwidget main loop. Easiest solution would be to use a sync bus handler (which you already have) and dispatch all messages from there to some callback on the wxwidget main loop.
I have a C# application, which I'm writing to try automate data extraction from a serial device. As the title of my question says, I have tried the exact same commands in Putty and I get data back. Could somebody please tell me what I have missed out, so that I can get the same data out with my C# application please?
Basically, I need to COM6, a speed/baud of 57600, and send the command without quotes "UH". I should be presented with a few lines of text data, which appears to only work on Putty.
As a quick test, I threw this together:
private void SerialPort serialPort = new SerialPort();
private void getHistory_Click(object sender, EventArgs e)
{
serialPort.DataReceived += new SerialDataReceivedEventHandler(serialPort_DataReceived);
serialPort.PortName = "COM6";
serialPort.BaudRate = 57600;
serialPort.Open();
if (serialPort.IsOpen())
{
serialPort.Write("UH");
}
}
private void serialPort_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
string result = serialPort.ReadExisting();
Invoke(new MethodInvoker(delegate{ textbox1.AppendText(result); }));
}
The DataReceived event does get fired, but it only returns back the "UH" I sent up, no further data. Any help with this problem would be highly appreciated!
Justin
Well, without further detail of the device in question, it is hard to say for sure, but two things spring to mind:
Firstly, what comms protocol does the device require? You have set up the baud rate, but have no mention of data bits, parity, or stop bits. I think the .NET serial port class defaults to 8,N,1. If your device is the same then you should be fine. If it is not, then it won't work.
Secondly, does the device require any kind of termination to the data to define a complete packet? Commonly this can be the data sent is appended with a carriage return and a line feed (0x0D and 0x0A), or perhaps is has a prefix of STX (0x02) and a suffix of ETX (0x03).
Any message that the device responds with is likely to be in the same format too.
I don't know how Putty works, but check the setup and see if it is appending anything to the message you type, and the protocol. Hyperterminal does this too, so you could test it with this also.
I am trying to register to a "Device added/ Device removed" event using WMI. When I say device - I mean something in the lines of a Disk-On-Key or any other device that has files on it which I can access...
I am registering to the event, and the event is raised, but the EventType propery is different from the one I am expecting to see.
The documentation (MSDN) states : 1- config change, 2- Device added, 3-Device removed 4- Docking. For some reason I always get a value of 1.
Any ideas ?
Here's sample code :
public class WMIReceiveEvent
{
public WMIReceiveEvent()
{
try
{
WqlEventQuery query = new WqlEventQuery(
"SELECT * FROM Win32_DeviceChangeEvent");
ManagementEventWatcher watcher = new ManagementEventWatcher(query);
Console.WriteLine("Waiting for an event...");
watcher.EventArrived +=
new EventArrivedEventHandler(
HandleEvent);
// Start listening for events
watcher.Start();
// Do something while waiting for events
System.Threading.Thread.Sleep(10000);
// Stop listening for events
watcher.Stop();
return;
}
catch(ManagementException err)
{
MessageBox.Show("An error occurred while trying to receive an event: " + err.Message);
}
}
private void HandleEvent(object sender,
EventArrivedEventArgs e)
{
Console.WriteLine(e.NewEvent.GetPropertyValue["EventType"]);
}
public static void Main()
{
WMIReceiveEvent receiveEvent = new WMIReceiveEvent();
return;
}
}
Well, I couldn't find the code. Tried on my old RAC account, nothing. Nothing in my old backups. Go figure. But I tried to work out how I did it, and I think this is the correct sequence (I based a lot of it on this article):
Get all drive letters and cache
them.
Wait for the WM_DEVICECHANGE
message, and start a timer with a
timeout of 1 second (this is done to
avoid a lot of spurious
WM_DEVICECHANGE messages that start
as start as soon as you insert the
USB key/other device and only end
when the drive is "settled").
Compare the drive letters with the
old cache and detect the new ones.
Get device information for those.
I know there are other methods, but that proved to be the only one that would work consistently in different versions of windows, and we needed that as my client used the ActiveX control on a webpage that uploaded images from any kind of device you inserted (I think they produced some kind of printing kiosk).
Oh! Yup, I've been through that, but using the raw Windows API calls some time ago, while developing an ActiveX control that detected the insertion of any kind of media. I'll try to unearth the code from my backups and see if I can tell you how I solved it. I'll subscribe to the RSS just in case somebody gets there first.
Well,
u can try win32_logical disk class and bind it to the __Instancecreationevent.
You can easily get the required info
I tried this on my system and I eventually get the right code. It just takes a while. I get a dozen or so events, and one of them is the device connect code.