Android SDK

artik

Hello,

I working on an open source live stacking android app and I want to add ASI ZWO support.

It is enabled in Linux variant using normal ASI SDK and libuvc for cameras that support UVC protocol like sv105.

Currently I work with UVC based cameras and the workflow on Android is following:

I ask permission to access USB device from Java App
I access the device and get file descriptor
I pass the file descriptor to C++/NDK code and open camera using libuvc that is linked against libusb and has android specific option to open camera from file descriptor.

This setup works fine with SVBony's sv105 and other webcams.

I've looked into ASI ZWO SDK. There is Java API to access the device, ask permissions etc, but since the application is written in C++/OpenCV with only small portion using Java/Android API I want to use C++ API but I don't see an api to open camera from file descriptor.

What is the workflow you suggest to access the device from C++ while getting permissions (do I need?) in Java UI.

Thanks

Software@ZWO

artik Hi Artik, I'm not good at Android program development. I am good at using C++for development on PC. In the ZWO ASI SDK, there is an API called ASIOpenCamera, which is used to open the camera. You can try to find this API.
Best Regards.

artik

Software@ZWO

API called ASIOpenCamera, which is used to open the camera.

I clearly understand and use this API, however under Android you need to request permissions as USB device aren't directly accessible so you get permission from Android USBManager and can get File Descriptor.

But there is no API to open camera from file-descriptor.

Software@ZWO

artik Hi Artik, I'll consult with other colleagues. I hope I can help you. But I'm not sure if I can find a solution.
Best Regards

artik

Hi,

I fail to open a camera even from Java API (android 11).

After getting permission on access USB I still can't call ZwoCamera.getNumOfConnectedCameras(); or ZwoCamera.getCameraProperty(0)

For UVC device I can create it using fd that I can access by calling

        UsbManager manager = (UsbManager) getSystemService(Context.USB_SERVICE);
        UsbDeviceConnection connection = manager.openDevice(device);
        int fd = connection.getFileDescriptor();*/

And that access the device.

Also note that ASICap works perfectly. But I can't access device using ASI Android SDK.

I can use SVBony's UVC cameras but I can't operate ASI cameras.

artik

This code: https://github.com/artyom-beilis/android_live_stacker/blob/web_ols/app/src/main/java/dom/domain/LiveStackerMain.java#L163

ZwoCamera.openCamera(camid) fails under latest SDK.

If I copy shared objects from ASICAP: libusb-1.0.so, libzwo_camera.so and libASICamera2.so

it works and I can work with camera without any issues.

Please release up-to-date SDK!

Zzzz

Thank you very much for your feedback, we have submitted your question to the development team

laheller

Hi!
@artik

I have similar problem:
How to pass the USB device file descriptor (FD) got from Android Java API to the ZWO native methods?

BR,

Ladislav

artik

Hi, sorray for late replay.

What I do I open the camera in Java ASI API and get camera id.

Once it is open I just pass camera id and use it from native API. Looks like ASI SDK does not allow me.

Here I open camera: https://github.com/artyom-beilis/android_live_stacker/blob/web_ols/app/src/main/java/org/openlivestacker/LiveStackerMain.java#L331

And than in native code I use id as camera is open outside: https://github.com/artyom-beilis/OpenLiveStacker/blob/main/src/asi_camera.cpp#L46

So I only call init with id.