Recently I have built a virtual camera filter using Vivek's VCam (http://tmhare.mvps.org/downloads.htm) in directshow but it works only in softwares which can show user mode filters. So to make my virtual device available in all softwares I have to built a kernel mode driver.
I have two questions.
Can I somehow overcome this problem with user mode directshow filter?
If not how can I get camera streaming through AVStream avshws driver available in WDK sample drivers or if there is anyother easy solution for it then please suggest?
Related
I'm currently working on an experimental Android Kernel (Research). I'actually trying to find some ways to preserve battery charge by implementing a kind of power management tool on the kernel level. I'm working on the msm-hammerahead kernel (used by the nexus 5 running Android 5.0).
I'm trying to figure out if there exists a way to switch between network types (2G,3G,Wifi) at runtime. I know that there exist the possibility to switch the default network type within the build.prop file(ro.telephony.default_network).
Does anybody know if it is even possible to achive this?
The android kernel is not the place to look for network switching. build.prop is also useless for this because it just contain the default boot values.
Switching network interfaces is a very bad idea, because the android framework need to be synchronized with the lower linux layer state.
I would suggest checking the ConnectivityManager.java in the android framework to understand better how the network switching works.
I need to create several local virtual IP Cameras for a project I'm making. I have tried several software, and the closest I have gotten was with magic camera, because it would let me create a virtual camera, but it wont let me assign a source to that camera. I need to assign an IP address and a username with a password, so that I access the IP camera's video and use that virtual camera in a program I'm developing. the thing is that the Camera's brand is not supported by Labview, so I need to use a virtual local camera to use these cameras (3S Vision IP Cameras).
Thanks in advance!
From the National Instruments Support Knowledgebase:
Connecting to an Arbitrary MJPEG IP Camera with IMAQdx Using Third Party Virtual Camera Emulator
http://digital.ni.com/public.nsf/allkb/9446A8C25CC99F7586257A56004D513D
Here are the options for using an IP cameras in LabVIEW as of 2019:
(in case someone like me still need this)
Use Vision Acquisition Software 14.5 (February 2015)
(with LabVIEW 2014 SP1 and Vision Development Module 2014-2017 SP1)
Pros:
Official, native support;
Any # of cameras.
Cons:
You lose all the features introduced in newer versions of LabVIEW;
Cameras must support and be configured to stream in MJPEG over HTTP.
Additional info:
It's the last version to support arbitrary IP cameras. Basler and Axis IP cameras were supported until VAS 19.0.
Cameras in the same subnet should be detected automatically. If cameras are in another network, you can try to add them manually as follows:
Go to the %Public%\Documents\National Instruments\NI-IMAQdx\Data\ folder;
Open or create a file IPCameras.ini in a text editor;
If creating, place an IPCameras section on a first line:
[IPCameras]
Add a line for each camera in a following format:
cameraSerialNumber = IPAddress, MJPEG stream URL, camera brand, camera description
Save your changes and restart NI MAX.
Use DirectShow device (webcam) emulator
NI-IMAQdx driver supports USB 2.0 cameras through the DirectShow interface. By using software which creates such interface for IP cameras, they can be used as regular USB 2.0 cameras.
There are multiple tools available:
IP Video Source
Pros:
Free;
Any # of cameras.
Cons:
Each camera must be added manually through emulator's settings;
Each camera's resolution must be set manually in emulator's settings;
Cameras must support and be configured to stream in MJPEG over HTTP(S);
32/64-bit versions work independently of each other. NI MAX is a 32-bit application, so it won't show cameras emulated by 64-bit tool. However, they are still detected and can be used in LabVIEW with IMAQdx VIs.
Additional info:
Camera's alias displayed in LabVIEW can be changed in a following way:
Go to the %Public%\Documents\National Instruments\NI-IMAQdx\Data\ folder;
Select one of camX.iid files and open it in a text editor;
Find an attribute InterfaceName and set its value to a desired name. See Vendor attribute's value for a name you set to that camera in emulator's settings;
Save your changes and rename this file to the same name;
Restart LabVIEW.
Moonware Universal Source Filter [more info]
Pros:
Supports JPEG/MJPEG/MPEG4/H264 over HTTP/RTSP;
Hardware decoding;
Low latency;
Multiple cameras.
Cons:
32-bit only. 64-bit version is not likely to happen;
Adds a watermark to an image (free version) / Paid: $49 per PC (no watermark);
Each camera must be added manually through emulator's settings.
and more
Use Multimedia for LabVIEW add-on
Pros:
Native interface (LabVIEW API for FFmpeg libraries);
Supports most codecs and protocols;
Any # of cameras;
Full control over data acquisition and processing (down to individual FFmpeg options).
Cons:
Paid: $949 per PC (developer license), $19 per PC (runtime license), 30 days trial;
Lower-level analog of NI-IMAQdx driver (see more complicated).
Use libVLC to receive images from a camera
(or another similar library)
Pros:
Free;
Supports most codecs and protocols;
Possibility of hardware decoding (depends on library usage);
Any # of cameras.
Cons:
You'll have to interface with libVLC library directly through the Call Library function node;
To receive video frame by frame you'll have to write a simple C library which will be called by libVLC to provide a frame (see example below in a linked thread).
This question is regarding file transfer using AllJoyN
I am using the basic_client & basic_service files for Windows 64 Bit desktop machine and I was able to build and run it successfully to transfer files from Client to Service.
Also I am able to transfer files between two phones in Android using the Android sdk with the FIle Transfer sample provided which in turn uses the FileTransferComponent.
Now I am trying to make the discovery part work for the Android devices and the Desktop. THe desktop discovers the Android device but the Android device wont discover the desktop client. Could you please let me know what I am doing wrong here?
Also the file transfer modules(Like OfferFile,RequestOffer) are handled by the bus in Android whereas in Windows client, there is a FileTransfer interface implemented for the same to transfer data using input-output stream. Could you please help me understand how I can achieve the same filetransfer between the two clients when their implementation is different? Or should I use a different mechanism for this purpose?
Awaiting your reply
I am currently trying to write a network monitoring software for windows mobile 6. I googled a lot and some people say that it is not possible to use a NDIS driver or WinPcap or so for monitoring any network interface. Others say that it is possible. Fact is, that I found no exaples, nor any sourcecode on the net.
Therefore I ask this community: Is it possible to write a packet capturing tool that works on data-link layer for windows mobile in C or C#?
with best regards
Desktop and Server Windows products have a very defined, generic, and pluggable structure into which you can insert hooks into the network layer. (Look up LSP or Layered Service Provider - this is how AntiVirus/Firewall programs plug themselves into monitoring your network traffic). As far as WinPCap, it plugs in one level lower at the NDIS driver level, but regardless, Windows Mobile just is not nearly as flexible when it comes to this. I don't necessarily think it's just Microsoft being short-sighted here, though - it takes much more power to provide a generic and pluggable LSP or NDIS layer that most mobile devices just can't afford.
The most important point here - NDIS Packet Capturing is not supported for Windows Mobile. Closest you can get to a mobile platform with packet capture is Windows Embedded CE.
So, in order to capture network traffic for Windows Mobile you would need to develop your own NDIS driver framework. Not a small task.
Windows Mobile uses Windows CE.
NDIS is very much present on Windows Mobile, so you can write an intermediate driver to capture traffic.
However, it already has netlog which should do the work for you: http://msdn.microsoft.com/en-us/library/ms883126.aspx
I'm wondering if there is a way to create an asp.net webpage that will connect a visitors USB device to an application on the windows bases server? This way we avoid having to install a software on the visitors computer to control a USB device update that they purchase form us.
All they have to do is visit our update page, plug their deivce to the USB, and have our site update the usb hardware.
Possible? or am I dreaming? :)
i found software like: USB over IP, and few others. But not show ure its possible to create a C# or vb.net based ASP.net page to control the visitors USB device.
Please advise.
In general, Web pages and scripts that run in browsers are limited in what local system resources they can access. Direct access to hardware like USB devices has obvious security implications.
The only way I can think of to do this might be an ActiveX control (IE only, I think) or some other kind of browser plugin.
One possibility is building a webserver into the USB device. Give the device internet access, and get it to download its own firmware in a process controlled through the webpage that the usb device serves.
Note that I have no idea if this is actually possible, just thought I'd throw in this different way of looking at the problem.
It is possible to create an ActiveX/.NETcontrol/Java Applet that will do it.
Granting the rights to this thing to access local devices will require certain security setup which can be automated, but in any case will require some user consent/interaction
I see here 2 ways:
ActiveX control
The problem is that the user should first download and install the
ActiveX from an Internet web server or from a local file
USB Device driver + DHCP Server + Web server embedded in the
device
Your USB device, once plugged, should present itself as a "Virtual
Ethernet Interface" in order for Windows to add the driver to the
list of the Internet Connections.
The Device should have also a DHCP server in order to give Windows
an IP address. Beware of the fact
The USB Device should also have an HTTP server.
At the end of this process, Windows will have 2 IP addresses.
Now you have to figure out how to have IE point to the index.html
file of the device.
Buy/Find a commercial software
You are not the first guy on this planet that has similar
requirements.
The only way I can possibly imagine doing this is through JAVA
EDIT: Looks like there might be an ActiveX way to do this as well, though ActiveX is Internet Explorer only, which limits it's usability.