I'm messing with the idea of writing a small program to mirror output of a video capture device. If you buy a video capture device you can only use it with one program at a time because the device gets locked. Instead of buying a second capture card id like to write a program to accept input from my capture device and expose the output to other applications.
Capture Device----->Program---->Flash Media Encoder
I've never done this type of thing before. Is it device driver related? Can I make my program look like a capture device to other programs without digging in device driver dev?
If someone could point me in the right direction that would be great.
Can I make my program look like a capture device to other programs without digging in device driver dev?
-No, I'm afraid not. You'd need to do exactly that, write a driver or capture source of your own. You could make some interface to serve up image to multiple apps (what a great idea!) but then it would need to be standardised, and you'd need other companies or developers to use that interface. Again a great idea but you'd need to agree on the feature set - and each developer would likely want something new or different.
(If you are talking about particular/specific other programs, they might have a particular interface you can work with already..)
(I was also assuming you were talking about realtime video capture: if you're talking about photo capture etc, you could write an image file to disk, and then import into the other apps ... not as joined up or integrated as ideal though)
Hope that helps - not an ideal situation though!
I will not say it is impossible, but I will say it is impossible in C# because this will require you to write a device driver software which can emulate virtual capture devices which your other program can use and your program can capture actual capture device and mirror or split the data to virtual capture devices that your device driver will create.
Very much same to Virtual CD Rom Drives that we can create with some software, you will need windows device driver kit for that.
You can write combination of application, one device driver and you can have some sort of C# api or program to control the operation.
Related
If I need to post this elsewhere let me know.
We have some old software thats being re-written, that uses a printerdriver to a propriatery printer.
I need to rewrite the software bypassing the print driver and go directly to the printer. I do have the specs for the printer communication, thats fine, but what Id like to do is monitor the communications to the printer to view its contents (from the existing software that Im re-writing) and compare it to the specs, and what I will be sending it for validation.
I have to make sure Im not missing anything.
Any ideas on how I might be able to accomplish this?
Thanks
To capture the traffic you have to basic options.
1. Use software
If you are using ethernet, you can use a program like WireShark or USBTrace to capture the packets that are being sent out. There are similar programs for USB.
2. Use hardware
Another option would be to use an external logic analyzer. It's basically a box that sits in-between the computer and the printer that captures all the data, then uses software to decode it. There are some inexpensive options available (USBEE, Bus Pirate, and Total Phase Beagle.
I own a USBEE and I've used it to debug a simple USB device. It works well enough for that. The software is a little clunky though.
I was wondering if anyone knows how (or even if it is possible) to monitor and trigger an action when a computer running windows (7-8) starts reciving a file transfer from over the network onto one of its drives.
Bonus points if I can find out how big the file is that the other guy is placing on my machine and how much is done etc...
I want to know if there is any API in windows, or snippit of code, or some other API that provides any of this functionality.
I still want to be able to recive files, I just want to manage them better. I am on a network with over 90 computers and this software that I wish to write would be running on most of them.
Of course you can (after all it's what an Antivirus program does) but it's NOT easy and probably you'll see it's more comfortable to do in C than in C#. I'm sure there's a .NET porting of WinPCap anyway you can always P/Invoke.
Start reading about Network Monitor SDK on MSDN. It's not an easy task, you have to capture a specific set of frames, you may use a Network Packet Monitor to inspect the content and the type of the packets you have to capture and parse.
I'm not sure but you may take a look to QoS API (start reading this article), it should provide something you can use.
Just a quick one, if anyone knows:
Is it possible to display a TomTom devices screen on a computer (so I can interface with it's navigation ability?)
They have an SDK, however that does not have any useful information on this question, but TomTom Home can do it - so can I? C# / C++ / Whatever.
Cheers
TomTom is running linux so you can get the raw image data from /dev/raw.
cat /dev/fb > /mnt/sdcard/screenshot.raw
on the device should do it
Then you need to transfer it to your computer (needs to be done quickly).
This should be possible to do over Bluetooth, over USB or possibly by using a Eye-Fi SD card.
I don't think it is possible to do it any other way.
Access the device by Bluetooth console
I have a MAYA 44 USB sound card and would like to interface it with C#. I want to record from the provided microphones and produce a data array.
I have found examples when using the internal sound card from my laptop but when it comes to external it does not quite work.
Has anyone every connected the above sound card with C# please?
Have you had a look at the DirectSound API (Windows only though, I think). Might provide what you're after.
On how to record audio with C# in general there are already multiple threads on SO, so I won't talk about that.
I see two possible causes for your program which have different solutions:
You need to change which audio sources are muted in the windows volume control ("sndvol32.exe /R")
When opening the audio device there are multiple devices. And you're simply opening device 0 instead of enumerating them and perhaps choosing another one. The external sound-card might appear as a second device.
Is there an easy way to programmatically determine the speed (or version) of a USB port? I'm looking to control the speed of data sent to a usb port based its maximum bandwidth.
If you need a solution for Windows this should be a good start:
http://msdn.microsoft.com/en-us/library/ms793313.aspx
Basically you should try this:
Enumerate the USB devices and the symbolic names to their drivers
Open a handle to the USB device driver through its symbolic name via CreateFile
Perform a DeviceIoControl on the driver handle with the control code IOCTL_USB_GET_NODE_CONNECTION_INFORMATION_EX. This will have you returned the structure USB_NODE_CONNECTION_INFORMATION_EX. There you have a member there called Speed of the type USB_DEVICE_SPEED.
(Close the driver handle)
This could also be interesting for you: CodeProject: Enumerate Properties of an Installed Device
To answer your question, I'm sure that there are ways of getting the information you need. I don't know the answer for windows, but Linux has files you can read within the sysfs directory structure.
Speed control is usually taken care of by the drivers and the hardware controlling the bus. Most modern USB controllers really have 2 controllers per port connected. 1 for the slower speed 12Mbps USB 1.0, and another for the higher pseed 480Mbps USB 2.0. There is a magic switch inside that connects it properly. The driver itself makes sure that everything is enumerated properly, controls the flow, etc. A higher level "user-space" application typically doesn't need to worry about these things.
Also, if you have a device that is capable of running at faster than 12Mbps, and you plug it into a 12Mbps port, it'll get dragged down to 12Mbps whether you like it or not. Is it that you want to know that is got dragged down?