Good day,
I would like to take this opportunity to give my many thanks to the people of stackoverflow.com.
I have been new to coding, .net, over the past year, and I have always found stakoverflow to be a fantastic base of knowledge for learning. I spent the last couple weeks working, in depth, on a speech recognition project I am going to use with the upcoming release of Media Browser 3. Originally, the idea was to build a recognizer and have it control media. However as I moved through the different namespaces for speech recognition, it lead me into the realm of the Microsoft Kinect sensor. The more I use the kinect device, the more I would like to use some of the skeleton tracking it has to offer. Which leads me to my question.
I am not interested in build a WPF application that displays a window of what the kinect is seeing. This is part of a Form application, in which I would like to support only two of three gestures.
The idea is for it to watch for three gestures and simulate a key press on the keyboard.
So first I enable skeletonframe before the the audio for the recognizer, because I had read on here somewhere that enabling the skeleton after the audio canceled the audio for some reason.
Then I add some event handlers to my form.
I added skeletonFrameReady event.
I suppose my main questions would be, am I on the right track with skeleton tracking? Is it possible to do this from a form application without trying to draw th skeleton?
Thank you again,
I hope I made sense, sorry for my ignorance.
Ben
It is possible of course. For gesture recognition you can make a comparison between the positions of the joints (In the method that skeletonFrameReady event calls, which is called several times per second).
If you want to recognize complex gestures (like waving a hand), I suggest you take a look at this page http://blogs.msdn.com/b/mcsuksoldev/archive/2011/08/08/writing-a-gesture-service-with-the-kinect-for-windows-sdk.aspx and download the sample code there. (which is hidden in the last paragraph :)
Main idea is checking for predefined gesture segments with the correct order (If the segment1 is successful, look at segment2. If segment2 is paused, look at segment2 again until it is either successful or failed).
Hope this helps.
Related
For the past few months I've been looking into developing a Kinect based multitouch interface for a variety of software music synthesizers.
The overall strategy I've come up with is to create objects, either programatically or (if possible) algorithmically to represent various controls of the soft synth. These should have;
X position
Y position
Height
Width
MIDI output channel
MIDI data scaler (convert x-y coords to midi values)
2 strategies I've considered for agorithmic creation are XML description and somehow pulling stuff right off the screen (ie given a running program, find xycoords of all controls). I have no idea how to go about that second one, which is why I express it in such specific technical language ;). I could do some intermediate solution, like using mouse clicks on the corners of controls to generate an xml file. Another thing I could do, that I've seen frequently in flash apps, is to put the screen size into a variable and use math to build all interface objects in terms of screen size. Note that it isn't strictly necessary to make the objects the same size as onscreen controls, or to represent all onscreen objects (some are just indicators, not interactive controls)
Other considerations;
Given (for now) two sets of X/Y coords as input (left and right hands), what is my best option for using them? My first instinct is/was to create some kind of focus test, where if the x/y coords fall within the interface object's bounds that object becomes active, and then becomes inactive if they fall outside some other smaller bounds for some period of time. The cheap solution I found was to use the left hand as the pointer/selector and the right as a controller, but it seems like I can do more. I have a few gesture solutions (hidden markov chains) I could screw around with. Not that they'd be easy to get to work, exactly, but it's something I could see myself doing given sufficient incentive.
So, to summarize, the problem is
represent the interface (necessary because the default interface always expects mouse input)
select a control
manipulate it using two sets of x/y coords (rotary/continuous controller) or, in the case of switches, preferrably use a gesture to switch it without giving/taking focus.
Any comments, especially from people who have worked/are working in multitouch io/NUI, are greatly appreciated. Links to existing projects and/or some good reading material (books, sites, etc) would be a big help.
Woah lots of stuff here. I worked on lots of NUI stuff during my at Microsoft so let's see what we can do...
But first, I need to get this pet peeve out of the way: You say "Kinect based multitouch". That's just wrong. Kinect inherently has nothing to do with touch (which is why you have the "select a control" challenge). The types of UI consideration needed for touch, body tracking, and mouse are totally different. For example, in touch UI you have to be very careful about resizing things based on screen size/resolution/DPI... regardless of the screen, fingers are always the same physical size and people have the same degreee of physical accuracy so you want your buttons and similar controls to always be roughly the same physical size. Research has found 3/4 of an inch to be the sweet spot for touchscreen buttons. This isn't so much of a concern with Kinect though since you aren't directly touching anything - accuracy is dictated not by finger size but by sensor accuracy and users ability to precisely control finicky & lagging virtual cursors.
If you spend time playing with Kinect games, it quickly becomes clear that there are 4 interaction paradigms.
1) Pose-based commands. User strikes and holds a pose to invoke some application-wide or command (usually brining up a menu)
2) Hover buttons. User moves a virtual cursor over a button and holds still for a certain period of time to select the button
3) Swipe-based navigation and selection. User waves their hands in one direction to scroll and list and another direction to select from the list
4) Voice commands. User just speaks a command.
There are other mouse-like ideas that have been tried by hobbyists (havent seen these in an actual game) but frankly they suck: 1) using one hand for cursor and another hand to "click" where the cursor is or 2) using z-coordinate of the hand to determine whether to "click"
It's not clear to me whether you are asking about how to make some existing mouse widgets work with Kinect. If so, there are some projects on the web that will show you how to control the mouse with Kinect input but that's lame. It may sound super cool but you're really not at all taking advantage of what the device does best.
If I was building a music synthesizer, I would focus on approach #3 - swiping. Something like Dance Central. On the left side of the screen show a list of your MIDI controllers with some small visual indication of their status. Let the user swipe their left hand to scroll through and select a controller from this list. On the right side of the screen show how you are tracking the users right hand within some plane in front of their body. Now you're letting them use both hands at the same time, giving immediate visual feedback of how each hand is being interpretted, and not requiring them to be super precise.
ps... I'd also like to give a shout out to Josh Blake's upcomming NUI book. It's good stuff. If you really want to master this area, go order a copy :) http://www.manning.com/blake/
i have a media player in vb form...with 2 files in a listbox as a playlist
now i want to create a fade between changing these files as a transition how can i do that...
You can't do this with the MediaPlayer control, unless you "fake" it by merging the two videos into one (handling the overlap transition from the first to the second in your code) and then playing the single merged video.
DirectShow can do this in theory, but programming DirectShow is difficult (all the more so from .Net) and it's obscure enough now that you won't find many people to help you. Also, from my experiments into this area (I was trying to use DirectShow to transition from one video w/sound to the next without any interruption or slight pausing), it appears that DirectShow can play one video at a time with no problems at all, but on some systems (including mine) it can't handle playing two at once. To do a cross-fade transition, you need to have both graphs running during the overlap time, which my computer at least was never able to handle.
I would check out WPF and see if its controls can do this. I'm not sure they can but it's possible.
I'm new in iPhone development, and I want to make a custom Reel/Spinner like the Reel in many iPhone fishing games, and I want capture the touch events, such as if the reel is moved to the right/left.
Where should I start?
Thank You!
I would look at using OpenGL ES.
On the other hand, you can often get very good results with just old fashion "flipbook" animation created by simply displaying slightly different images in sequence.
If you're just starting out, I would suggest you go over the MoveMe application tutorial. It will teach you many of the fundamentals of detecting touch events and responding using animations. If you need another sample, you can also have a look at the Touches sample.
Once you feel comfortable with detecting touch events, I would look into Core Animation. The Cookbook has a lot of examples on how to do many different tasks. The Animation Programming Guide also has some valuable information as to how to do various types of animations.
If you have any specific questions while figuring things out, post them here, and welcome to Stack Overflow!
I recently purchased a Magic Mouse. It is fantastic and full of potential. Unfortunately, it is seriously hindered by the software support. I want to fix that. I have done quite a lot of research and these are my findings regarding the event chain thus far:
The Magic Mouse sends full multitouch events to the system.
Multitouch events are processed in the MultitouchSupport.framework (Carbon)
The events are interpreted in the framework and sent up to the system as normal events
When you scroll with one finger it sends actual scroll wheel events.
When you swipe with two fingers it sends a swipe event.
No NSTouch events are sent up to the system. You cannot use the NSTouch API to interact with the mouse.
After I discovered all of the above, I diassembled the MultitouchSupport.framework file and, with some googling, figured out how to insert a callback of my own into the chain so I would receive the raw touch event data. If you enumerate the list of devices, you can attach for each device (trackpad and mouse). This finding would enable us to create a framework for using multitouch on the mouse, but only in a single application. See my post here: Raw Multitouch Tracking.
I want to add new functionality to the mouse across the entire system, not just a single app.
In an attempt to do so, I figured out how to use Event Taps to see if the lowest level event tap would allow me to get the raw data, interpret it, and send up my own events in its place. Unfortunately, this is not the case. The event tap, even at the HID level, is still a step above where the input is being interpreted in MultitouchSupport.framework.
See my event tap attempt here: Event Tap - Attempt Raw Multitouch.
An interesting side note: when a multitouch event is received, such as a swipe, the default case is hit and prints out an event number of 29. The header shows 28 as being the max.
On to my question, now that you have all the information and have seen what I have tried: what would be the best approach to extending the functionality of the Magic Mouse? I know I need to insert something at a low enough level to get the input before it is processed and predefined events are dispatched. So, to boil it down to single sentence questions:
Is there some way to override the default callbacks used in MultitouchSupport.framework?
Do I need to write a kext and handle all the incoming data myself?
Is it possible to write a kext that sits on top of the kext that is handling the input now, and filters it after that kext has done all the hard work?
My first goal is to be able to dispatch a middle button click event if there are two fingers on the device when you click. Obviously there is far, far more that could be done, but this seems like a good thing to shoot for, for now.
Thanks in advance!
-Sastira
How does what is happening in MultitouchSupport.framework differ between the Magic Mouse and a glass trackpad? If it is based on IOKit device properties, I suspect you will need a KEXT that emulates a trackpad but actually communicates with the mouse. Apple have some documentation on Darwin kernel programming and kernel extensions specifically:
About Kernel Extensions
Introduction to I/O Kit Device Driver Design Guidelines
Kernel Programming Guide
(Personally, I'd love something that enabled pinch magnification and more swipe/button gestures; as it is, the Magic Mouse is a functional downgrade from the Mighty Mouse's four buttons and [albeit ever-clogging] 2D scroll wheel. Update: last year I wrote Sesamouse to do just that, and it does NOT need a kext (just a week or two staring at hex dumps :-) See my other answer for the deets and source code.)
Sorry I forgot to update this answer, but I ended up figuring out how to inject multitouch and gesture events into the system from userland via Quartz Event Services. I'm not sure how well it survived the Lion update, but you can check out the underlying source code at https://github.com/calftrail/Touch
It requires two hacks: using the private Multitouch framework to get the device input, and injecting undocumented CGEvent structures into Quartz Event Services. It was incredibly fun to figure out how to pull it off, but these days I recommend just buying a Magic Trackpad :-P
I've implemented a proof-of-concept of userspace customizable multi-touch events wrapper.
You can read about it here: http://aladino.dmi.unict.it/?a=multitouch (see in WaybackMachine)
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all the best
If you get to that point, you may want to consider the middle click being three fingers on the mouse instead of two. I've thought about this middle click issue with the magic mouse and I notice that I often leave my 2nd finger on the mouse even though I am only pressing for a left click. So a "2 finger" click might be mistaken for a single left click, and it would also require the user more effort in always having to keep the 2nd finger off the mouse. Therefor if it's possible to detect, three fingers would cause less confusion and headaches. I wonder where the first "middle button click" solution will come from, as I am anxious for my middle click Expose feature to return :) Best of luck.
I just bought a Magic Mouse and I like it pretty much. But as a Mac Developer it's even cooler. But there's one problem: is there already an API available for it? I want to use it for one of my applications. For, example, detect the user's finger positions, swipe or stretch gestures etc...
Does anyone know if there's an API for it (and how to use it)?
The Magic Mouse does not use the NSTouch API. I have been experimenting with it and attempting to capture touch information. I've had no luck so far. The only touch method that is common to both the mouse and the trackpad is the swipeWithEvent: method. It is called for a two finger swipe on the device only.
It seems the touch input from the mouse is being interpreted somewhere else, then forwarded on to the public API. I have yet to find the private API that is actually doing the work.
get a look here: http://www.iphonesmartapps.org/aladino/?a=multitouch
there's a full working proof-of-concept using the CGEventPost method.
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all the best!
I have not tested, but I would be shocked if it didn't use NSTouch. NSTouch is the API you use to interact with the multi-touch trackpads on current MacBook Pros (and the new MacBooks that came out this week). You can check out the LightTable sample project to see how it is used.
It is part of AppKit, but it is a Snow Leopard only API.
I messed around with the below app before getting my magic mouse. I was surprised to find that the app also tracked the multi touch points on the mouse.
There is a link in the comments to some source that gets the raw data similarly, but there is no source to this actual app.
http://lericson.blogg.se/code/2009/november/multitouch-on-unibody-macbooks.html