I have an usb-camera with its drivers and dll with some functions to use this camera in my solutions. I want to use it in any wide-spread applications, to be able just to choose and use it in Skype, for instance. So. I want to develop something that will allow me to use this device as usual web-camera.
I've heard something about such technologies as "Upper-Level Filter Drivers" and "user-mode DirectShow source filter". Looks like it something that can help.
So the question is: what technologies exist for such tasks? What technology should I choose to solve my problem if I have no skills of driver development?
Skype still uses DirectShow for video capture and user mode filter will do the job. Still Skype makes certain unreasonable assumptions that limit compatible source filters, such as if the developers stopped development/testing as soon as they had their favorite USB cam working and ignoring all other devices users might possibly want to attach.
One of the options you were suggested (in Russian - 1, 2) was to develop a kernel mode driver so that your device is visible to apps through standard WDM Video Capture Filter. This is possible and would work, though in my opinion it is a huge overkill.
Fitting custom source filter is not easy because Skype does not like a debugger attached, however driver development is really a completely different story.
The Skype Forum link you refer to is clearly misleading. The poster complains that Skype update broke compatibility with video sources. And response from admin is about audio devices, and is irrelevant.
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I've got a big ask here, but I am hoping someone might be able to help me. If there's another site you think this should be posted on, please let me know.
I'm the developer of the free app Amphetamine for macOS and I'm hoping to add a new feature to the app - keeping a Mac awake while in closed-display (clamshell) mode while not having a keyboard/mouse/power adapter/display connected to the Mac. I get requests to add this feature on an almost daily basis.
I've been working on a solution (and it's mostly ready) which uses a non-App Store helper app that must be download and installed separately. I could still go with that solution, but I want to explore one more option before pushing the separate app solution out to the world.
An Amphetamine user tipped me off that another app, AntiSleep can keep a Mac awake while in closed-display mode, while not meeting Apple's requirements. I've tested this claim, and it's true. After doing a bit of digging into how AntiSleep might be accomplishing this, I've come up with 2 possible theories so far (though there may be more to it):
In addition to the standard power assertion types, it looks like AntiSleep is using (a) private framework(s) to apply non-standard power assertions. The following non-standard power assertion types are active when AntiSleep is keeping a Mac awake: DenySystemSleep, UserIsActive, RequiresDisplayAudio, & InternalPreventDisplaySleep. I haven't been able to find much information on these power assertion types beyond what appears in IOPMLibPrivate.h. I'm not familiar at all with using private frameworks, but I assume I could theoretically add the IOPMLibPrivate header file to a project and then create these power assertion types. I understand that would likely result in an App Store review rejection for Amphetamine, of course. What about non-App Store apps? Would Apple notarize an app using this? Beyond that, could someone help me confirm that the only way to apply these non-standard power assertions is to use a private framework?
I suspect that AntiSleep may also be creating a virtual keyboard and mouse. Certainly, the idea of creating a virtual keyboard and mouse to get around Apple's requirement of having a keyboard and mouse connected to the Mac when using closed-display mode is an intriguing idea. After doing some searching, I found foohid. However, I ran into all kinds of errors trying to add and use the foohid files in a test project. Would someone be willing to take a look at the foohid project and help me understand whether it is theoretically possible to include this functionality in an App Store compatible app? I'm not asking for code help with that (yet). I'd just like some help determining whether it might be possible to do.
Thank you in advance for taking a look.
Would Apple notarize an app using this?
I haven't seen any issues with notarising code that uses private APIs. Currently, Apple only seems to use notarisation for scanning for inclusion of known malware.
Would someone be willing to take a look at the foohid project and help me understand whether it is theoretically possible to include this functionality in an App Store compatible app?
Taking a quick glance at the code of that project, it's clear it implements a kernel extension (kext). Those are not allowed on the App Store.
However, since macOS 10.15 Catalina, there's a new way to write HID drivers, using DriverKit. The idea is that the APIs are very similar to the kernel APIs, although I suspect it'll be a rewrite of the kext as a DriverKit driver, rather than a simple port.
DriverKit drivers are permitted to be included in App Store apps.
I don't know if a DriverKit based HID driver will solve your specific power management issue.
If you go with a DriverKit solution, this will only work on 10.15+.
I suspect that AntiSleep may also be creating a virtual keyboard and mouse.
I haven't looked at AntiSleep, but I do know that in addition to writing an outright HID driver, it's possible to generate HID events using user space APIs such as IOHIDPostEvent(). I don't know if those are allowed on the App Store, but as far as I'm aware, IOKitLib is generally fine.
It's possible you might be able to implement your virtual input device using those.
So I've tried to tackle this problem for the last couple of weeks but come to a bit of a standstill. I'm trying to registering an RTSP stream from an IP address as a virtual webcam for use in another application (could be skype or similar). What I need is for my computer to add a virtual webcam to its device list. This should preferably be done through a C# script as devices could be added dynamically through a .NET program.
I have found similar questions on StackOverflow, but many of these are outdated, use Linux, or receives another stream format/protocol.
My approach so far has been using DirectShow filters and so far that has worked to a degree. Using Graphedit I can see my incoming stream by using an RTSP source filter. However, there are some problems:
The source filter was a trial, the full version is paid and pretty expensive
I have no experience with DirectShow filter programming
I only showed the stream through GraphEdit, there was no virtual driver registered so e.g Skype couldn't use the stream
So I guess my question boils down to:
Is my approach with DirectShow the only way to acheive what I'd like?
Is a filter the correct approach to use if Windows should list the stream as a webcam device?
Is vcam still the best example to look at to implement something like this?
Does any one know of similar, open source programs that acheive what I describe?
Anyway, I appreciate any help I can get!
Thanks.
The diagram below explains the applicability of virtual cameras:
You are trying to somehow mount a lower green or blue box so that it reads data from RTSP.
Note that more and more applications like new Skype are Media Foundation based (top right box on the diagram) and your filter based source is less and less applicable.
Creating a virtual camera which is recognized by various software assumes you are supplying a driver (red box). Even though such packages exist, I am not aware of any open source or even free which let you quickly start on this route.
DirectShow filter based sources (and you are yet to implement RTSP client there) will only be see by DirectShow based applications of the same bitness.
Most of touchpads on laptops don't handle multitouch, hence are not able to send swipe gestures to the OS.
Would it be possible to send some gestures to Windows from an external device, like a Teensy, or a recent Arduino, that can already emulate a keyboard and a mouse. I could send buttons 4 and 5 (mouse wheel up and down), but I would like to send a real swipe gesture (for example with a flex sensor...).
One of the ways that you could work with arduino and similar is to use the Microsoft .NET Microframework, which is an open source code, available for no cost from: Micro Framework
There are other frameworks available for the Artuino that you might want to use. So if you have a great idea on how to utilize the sensor hardware, then the output must meet certain specifications.
To be able to connect to your hardware that reads gestures, you will need to understand how drivers are created, so take a look at this: Info on drivers.
To find that type of information you would need to take a look at above link, this is for sensors, which would appear to be not quite what you are looking for, you are looking to use "gestures" but first you have to be able to make the connection to your device, this guide MIGHT help. I have reviewed it for other reasons.
There is a bunch of stuff to dig through, but first of all, imo, is to understand how to get your software to communicate with Windows 8. Let me know if you have any other questions. I am not the best person, you might want to refer to the community at the Micro Framework link shown above.
Good luck.
That's perfectly possible. What your effectively suggesting is that you want to create your own input peripheral like a trackpad and use that to send inputs. As long as windows recognizes this device as an input source it will work.
Edited on April 29th, content changed
Hello everyone,
I recently bought a Sony Ericsson mobile phone and I would like to add a missing feature myself. In fact I cannot actually disable Internet connection in an easy way when roaming, which cost me a lot of money last time I moved away ... So I would like to develop a little application that would just replace the actual Internet configuration with a fake configuration to avoid auto-connections.
So what I would like to know is how can I access programmatically to my phone settings? I know that Sony Ericsson provides a SDK to run Java applications on its customised JVM. So what I am actually looking for is to know if they extended the J2ME functionality to fit their devices requirements.
This is not well documented so I am asking this question with the hope that someone here already had experience with development targeted for Sony Ericsson devices.
Thanks.
NB: This is a Sony Ericsson Elm which is based on the Sony Ericsson OS with SE Java Platform 8.5.
Edit: I accepted QuickRecipesOnSymbianOS answer as it gave me a clue on the only feature that could have helped me, but which is unfornatunately missing. The Sony Ericsson Java Platform is the only API I could use to develop real programs on my phone. But the JP-8.5 does not implement the JSR-307 package which could help me in managing APN. Thanks everyone for your help.
Well, I hope you got the great Vivaz phone, not the Satio.
In order to learn about Symbian OS C++, first go to the Foundation website.
Relevant plug: the latest introduction to Symbian OS C++ in book form is Quick Recipes on Symbian OS
For now, you won't find a better way than Symbian OS C++ to manipulate your handset access points.
JavaME simply doesn't have the correct APIs for this, at least not until JSR-307 is implemented.
I believe Qt isn't integrated quite tightly enough just yet either but that should change soon enough. Keep an eye on it.
Extending the Symbian Python runtime to do what you want would require some Symbian OS C++ anyway.
Yes you will need to use Symbian C++ to modify the CommDB, which holds the list of connections. It is quite painful to work with it directly, but there are some utility classes that can help you out. Take a look at CApSelect, CApDataHandler and CApAccessPointItem, all in the developer library.
And yes, these will work on all modern Symbian handsets, independent of brand.
Note: My answer below assumed it was about a symbian device. Since it was actually a J2me device none of the below applies
The easiest way to achieve what you want to do is probably to just remove all the "destinations" when you want to prevent auto connections. Otherwise the device will test each destination in turn until it finds one that works.
You can also set up your destinations so that they are not allowed to be used automatically. This setting must be done individually for each destination.
You can also group your destinations and set one of the groups to the default. If you set the default to an empty group you should not get any automatic connections.
Note that I have not tested any of these methods myself. When I roam I turn off automatic updates in the apps that use them. Some apps can even detect when you are roaming and avoid auto connects.
There are S60 apps available that improves the connection management of vanilla S60, but I do not know if any of them can help you with your problem.
If you are dead set on doing the programming yourself you have to use the C++ SDK for Symbian S60 available from Forum Nokia. Java ME does not allow you to manipulate the destinations of the device.
The Elm device should have (I haven't verified this) the access point API originally designed by Nokia. Not sure whether you can use it for the purpose you want though. The J2me developer guidelines available from developer.sonyericsson.com should have all the information you need.
Simply I am asked to write an application for a smart device (smart cell phone), which will get the GPS coordinates from the device itself.
I have no smart device at all. And I am kind of lost among questions like how can I check if the device have a gps by using the code, if it has how can I obtain them in a "standard" way, do I need to be using frameworks like GeoFrameWork?
So, may somebody list the must or most required things I need to have ready?
Geoframeworks GPS.NET is free these days and it's pretty comprehensive so there's no point reinventing the wheel. It's also friendly to beginners which helps. I strongly recommend downloading it and playing with some of the sample apps. It's a bit tricky if you don't have a physical device to play around with but it does have GPS emulation classes that you can use.
All you need is a copy of VS2008 Pro with the Smart Device SDK installed.