I need to get raw frames from the Camera in YUV/YCbCr format on windows phone 8.1 (without Silverlight), I don't see any example on internet, is it possible using MediaCapture or CameraPreviewImageSource (Nokia SDK) ?
Thanks
The recommended way to process raw video frames on Windows Phone 8.1 is to write a custom MFT plug-in and then add it to the MediaCapture object via AddEffectAsync. The MFT acts as a DSP filter between the decoder and the XAML rich compositor.
You can choose the color space that you want to support in your MFT and Media Foundation will automatically insert color space converters for you. Keep in mind that the color spaces available on the Phone are limited. That said, NV12 is the standard color space for most video devices and is considered a 4:2:0 YUV color space.
While this sounds simple in theory it can be quite complex in practice. MFTs must be writing in C++ / MoCom. Writing an MFT does require rather deep knowledge of C++ and COM. I don't want to scare you away from giving it a try but it does have a learning curve.
Here is a sample for Windows Store that shows you how to create a MFT plug-in and add it to the MediaCapture object. Unfortunately for whatever reason this sample did not get converted to a Universal app. However, it should be easy to do the conversion. Since this is such a seminal sample I will request that we publish it as a universal app.
Media capture using capture device sample
I hope this helps,
James
Related
The short question: I am wondering if the kinect SDK / Nite can be exploited to get a depth image IN, skeleton OUT software.
The long question: I am trying to dump depth,rgb,skeleton data streams captured from a v2 Kinect into rosbags. However, to the best of my knowledge, capturing the skeleton stream on Linux with ros, kinect v2 isn't possible yet. Therefore, I was wondering if I could dump rosbags containing rgb,depth streams, and then post-process these to get the skeleton stream.
I can capture all three streams on windows using the Microsoft kinect v2 SDK, but then dumping them to rosbags, with all the metadata (camera_info, sync info etc) would be painful (correct me if I am wrong).
It's quite some time ago that I worked with NITE (and I only used Kinect v1) so maybe someone else can give a more up-to-date answer, but from what I remember, this should easily be possible.
As long as all relevant data is published via ROS topics, it is quite easy to record them with rosbag and play them back afterwards. Every node that can handle live data from the sensor will also be able to do the same work on recorded data coming from a bag file.
One issue you may encounter is that if you record kinect-data, the bag files are quickly becoming very large (several gigabytes). This can be problematic if you want to edit the file afterwards on a machine with very little RAM. If you only want to play the file or if you have enough RAM, this should not really be a problem, though.
Indeed it is possible to perform a NiTE2 skeleton tracking on any depth-image-stream.
Refer to:
https://github.com/VIML/VirtualDeviceForOpenNI2/wiki/How-to-use
and
https://github.com/VIML/VirtualDeviceForOpenNI2/wiki/About-PrimeSense-NiTE
With this extension one can add a virtual device which allows to manipulate each pixel of the depth stream. This device can then be used for creation of a userTracker object. As long as the right device name is provided skeleton tracking can be done
\OpenNI2\VirtualDevice\Kinect
but consider usage limits:
NiTE only allow to been used with "Authorized Hardware"
I am a beginner in Windows Phone app development. My goal is to create a simple augmented reality application which will include shape recognition (ex. hand or face). Additionally I would like to draw 3D objects on screen and place them in reality. The question is what is the best way to start development? Especially which toolkits do You advise to use? My current idea is to detect motion using Motion Class built in WP-SDK and use EmguCV to dectect and recognise shapes. And which library should I use to draw shapes (Direct3d or XNA) ? Is it a good way to start? I am confused if EmguCV is available on Windows Phone platform at all?
Additional info:
- platform will be WP7.5 or WP8
i'm working also on windows phone project, it was about face recognition but because lack libraries that can used in other things i change my project.
but there is FACESDK that could help you for Face recognition.
http://research.microsoft.com/en-us/projects/facesdk/
I would like to develop an interface to a Wireless WiFi IP camera and stream its video in a frame in my application. I never did such a thing and would appreciate any pointers.
how should I approach this task?
Have a look at my MJPEG Decoder on CodePlex. You'll find source + binaries for almost every Windows platform (WinForms, WPF, Windows Runtime, etc.) along with samples. Let me know if you have any questions.
There are couple options that you may consider. However, it is very important to define the stream/source of video transmitter.
How to use a web cam in C# with .NET Framework 4.0 and Microsoft Expression Encoder 4
Perform live video stream processing from CaptureElement & MediaCapture
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I recently moved from a PC to a MacBook Pro. I'm starting to go through tutorials on Objective-C and developing in Cocoa. I do a lot of image processing algorithm development work (pixel by pixel manipulation) in my day job so I'd like to get create a test image processing app or two for OS X. I'm struggling to figure out where to start - let's say I want to create a simple application (that I could reuse) like the following:
load an image from an open file option within a file menu
display this within the GUI.
Click a button to apply pixel by pixel processing
Update the displayed image
Save the processed image from the save option within the file menu
Any pointers or links would be most appreciated.
Thanks
Other info:
I'm pretty familiar with OpenCV within Linux - haven't looked at using it within Objective-C/Cocoa/Xcode environment yet though - not even sure if this would be a good idea?
I guess it would be nice to use GPU acceleration as well, but I'm not familiar with OpenGL/OpenCL - so I might have to put that one on the long finger for the moment.
As you are looking at the Apple platform, you should look into the CoreImage framework - it will provide you most of pre-baked cookies ready to be consumed in your application.
For more advanced purposes, you can start off with openCV.
Best of luck!!
As samfisher suggests, OpenCV is not that hard to get working on the Mac, and Core Image is a great Cocoa framework for doing GPU-accelerated image processing. I'm working on porting my GPUImage framework from iOS to the Mac, and it's entirely geared around making accelerated image processing easy to work with, but unfortunately that isn't working right now.
If you're just getting started on the Mac, one tool that I can point out which you might overlook is Quartz Composer. You have to download the separate Graphics Tools package from Apple's developer site to install Quartz Composer, because it's no longer shipped with Xcode.
Quartz Composer is a graphical development tool that lets you drag and drop modules, connect inputs and outputs, and do rapid development of some fairly interesting things. One task it's great for is doing rapid prototyping of image processing, either using Core Image or OpenGL shaders. I've even heard of people using OpenCV with this using custom patches. You can easily connect an image or camera source into a filter chain, then edit the filters and see live updates as you work on them, without requiring a compile-run cycle.
If you want some sample QC projects to play with, I have a couple of them linked from this article I wrote a couple of years ago. They both do the same color-based object tracking, with one using Core Image and the other OpenGL shaders. You can dig into that and play around to see how that works, without having to get too far into writing any code.
New to Mac OS X, familiar with Windows. Windows has DirectShow, a good number of built-in filters, COM programming, and GraphEdit for very fast prototyping and snooping on the graphs you've constructed in code.
I'm now about to go to the Mac to work with cameras, webcams, microphones, color spaces, files, splitting, synchronization, rendering, file reading, file saving, and many of things I've come to take for granted with DirecShow when putting together applications for live performance. On the Mac side, so far I've found ... nothing! Either I don't know where to look or I'm having the toughest time tying the Mac's reputation for its ease of handling media with a coherent programmatic ability to get in there and start messin' with media manipulatin' building blocks.
I've seen some weak suggestions to use gstreamer or some library for QT but I can't bring myself to believe that this is the Apple way to go. And I've come across some QuickTime documentation but I'm not looking to do transitions, sprites, broadcasting, ...
Having a brain trained on DirectShow means I don't even know how Apple thinks about providing DirectShow-like functionality. That means I don't know the right keywords and don't even know where to look. Books? Bought a few. Now I might be able to write some code that can edit your sister's wedding video (if I can't make decent headway on this topic I may next be asking what that'd be worth to you), but for identifying what filters are available and how to string them together ... nothing. Suggestions?
Video handling is going through a huge transition on the Mac at the moment. QuickTime is very old, but also big and powerful, so it's been undergoing an incremental replacement process for the past 5 years or so.
That said, QTKit is the QuickTime subset (capture, playback, format conversion and basic video editing) which is supported going forward. The legacy QuickTime APIs are still there for the moment, and probably will remain at least until its major features are available elsewhere, but are 32-bit only. For some involved video stuff you may end up needing to use it in places.
At the moment, iOS is ahead of the Mac because it could start from scratch with AV Foundation. The future of the Mac media frameworks will probably either be AV Foundation directly (with QTKit being a lightweight shim over the top) or an extension of QTKit that looks very similar.
For audio there's Core Audio which is on Mac and iOS and isn't going away any time soon. It's quite powerful but somewhat obtuse in places. Luckily online support is very good; the mailing list is an essential resource.
For filters and frame-level processing you've got Core Video as someone else mentioned, as well as Core Image. For motion graphics there's Quartz Composer which includes a graphical editor and a plugin architecture to add your own patches. For programmatic procedural animation and easily mixing rendering models (OpenGL, Quartz, video, etc.) there's Core Animation.
In addition to all of these, of course there's no reason you can't use open source libraries where the built-in stuff doesn't do what you want.
To address your comment below:
In QuickTime (and QTKit), individual data types like audio and video are represented as tracks. It may not be immediately clear that QuickTime can open audio as well as video file formats. A common way to combine audio and video would be:
Create a QTMovie with your video file.
Create a QTMovie with your audio file.
Take the QTTrack object representing the audio and add it to the QTMovie with the video in it.
Flatten the movie, so it doesn't simply contain a reference to the other movie but actually contains the audio data.
Write the movie to disk.
Here's an example from Blender. You'll see how the A/V muxing is done in the end_qt function. There's also some use of Core Audio in there (AudioConverter*). (There's some classic QuickTime export code in quicktime_export.c but it doesn't seem to do audio.)