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Capture still images with UWP MediaCapture (PIN_CATEGORY_STILL)

An alternative title could be: What happened to PIN_CATEGORY_STILL?
I am currently comparing images that were captured using DirectShow and PIN_CATEGORY_STILL with images that were captured using UWP MediaCapture.
On the device I am testing/playing around with DirectShow and MediaCapture, DirectShow detects a PIN_CATEGORY_STILL but I am not able to initialize an instance of MediaCapture with anything other than PhotoCaptureSource.VideoPreview.
MediaCaptureInitializationSettings settings = new()
{
VideoDeviceId = someDeviceId,
PhotoCaptureSource = PhotoCaptureSource.Photo
};
MediaCapture capture = new();
// this throws an exception
// "The capture source does not have an independent photo stream."
await capture.InitializeAsync(settings);
At this point I'm not even sure if PhotoCaptureSource.Photo is meant to be used as an equivalent to PIN_CATEGORY_STILL.
Images captured with PIN_CATEGORY_STILL are way brighter in a dark environment and have a much better quality (in file size and resolution) (which is clear to me, since I am using PhotoCaptureSource.VideoPreview for MediaCapture).
Considering this resource Win32 and COM for UWP apps, it seems like UWP MediaCapture does not use DirectShow underneath but MediaFoundation (which is meant to be a successor for DirectShow).
This article led me to this StackOverflow question Media Foundation is incorrectly marking still image capture stream descriptors as video capture, which basically states that MediaFoundation has no PIN_CATEGORY_STILL but returns 1 FPS as video capability for such devices (or profiles).
Since I am not directly using MediaFoundation nor C++, I tried testing this by querying GetAvailableMediaStreamProperties:
private void Foo()
{
var videoPreviewProperties = GetEncodingProperties(MediaStreamType.VideoRecord);
var photoProperties = GetEncodingProperties(MediaStreamType.Photo);
var videoRecordProperties = GetEncodingProperties(MediaStreamType.VideoPreview);
}
private List<VideoEncodingProperties> GetEncodingProperties(MediaStreamType streamType)
{
// MediaCapture was previously initialized with PhotoCaptureSource.VideoPreview
return MediaCapture.VideoDeviceController
.GetAvailableMediaStreamProperties(streamType)
.OfType<VideoEncodingProperties>()
.ToList();
}
None of these returns a VideoEncodingProperties with only 1 FPS.
To test MediaCapture any further I tried some of the sample applications from here UWP sample. I tried CameraAdvancedCapture, CameraOpenCV and CameraManualControls, but the results were not nearly as good as good old PIN_CATEGORY_STILL.
What happened to PIN_CATEGORY_STILL?
Is there any way to capture images without DirectShow/PIN_CATEGORY_STILL and still keeping this level of quality?
Any enlightenment is much appricated.

Read data via bluetooth using c#

I am using Lecia Disto e7100i which basically measures distance and area using laser. This device has bluetooth and can be paired with windows.
I am trying to develop an wpf app that reads the mesaured data using c#
There is no sdk that comes along with the device.
I have tried to use 32feet.Net but since there is no proper documentation I don't know where to start.
Is there any way that I can do to solve my problem?

This is not a full response, instead its more of a guideline on how to resolve your issue:
Pair the device with your Computer
Run the included software that displays the data somehow
Use WireShark to analyze the traffic
see if it is a standard protocol type or something custom
understand the protocol and reimplement it using c# and BluetoothSockets

To get started, you can try:
var client = new BluetoothClient();
// Select the bluetooth device
var dlg = new SelectBluetoothDeviceDialog();
DialogResult result = dlg.ShowDialog(this);
if (result != DialogResult.OK)
{
return;
}
BluetoothDeviceInfo device = dlg.SelectedDevice;
BluetoothAddress addr = device.DeviceAddress;
Console.WriteLine(device.DeviceName);
BluetoothSecurity.PairRequest(addr, "PIN"); // set the pin here or take user input
device.SetServiceState(BluetoothService.HumanInterfaceDevice, true);
Thread.Sleep(100); // Precautionary
if (device.InstalledServices.Length == 0)
{
// handle appropriately
}
client.Connect(addr, BluetoothService.HumanInterfaceDevice);
Also make sure that
Device appears in "Bluetooth devices" in the "Control panel".
Device is HID or change code accordingly.
Hope it helps. Cheers!

Try this demo project, and the following articles after that one.
Try to follow this tutorial
Here you can see a direct answer by the mantainer of 32feet, with which you can get in touch
Check also this answer

How to display 2 web camera preview in UWP?

Hello I displayed 1 webcam preview in UWP and that was a success.
But now I want to use 2 camera's preview on my program or be able to choose between the two cameras while connected 2 cameras on computer.
When I run 1 webcam preview, I referred to documentation on using MediaCapture and it was good.
But now I don't know how to display 2 camera previews or select a one between cameras.
Is it impossible?

Yes, it is possible :-) . The MediaCapture class takes the default camera when you call the InitializeAsync method without parameters, but there is another overload that allows you to specify the device ID.
The documentation shows how to discover video capture devices:
DeviceInformationCollection devices =
await DeviceInformation.FindAllAsync(DeviceClass.VideoCapture);
Now you can initialize multiple MediaCapture instances like this:
foreach ( var device in devices )
{
var mediaInitSettings =
new MediaCaptureInitializationSettings { VideoDeviceId = device.Id };
MediaCapture mediaCapture = new MediaCapture();
mediaCapture.InitializeAsync(mediaInitSettings);
//do something with the media capture
}
Naturally, when you want to display multiple previews, you will need to have multiple CaptureElements, each set to the specific MediaCapture instance you want.
However this approach is quite simplified. To make sure the concurrent capture and preview is supported, you must first ensure to query only cameras that support device profile using MediaCapture.IsVideoProfileSupported method as shown in the documentation and then also check find a concurrency-enabled profile common for both cameras - MediaCapture.FindConcurrentProfiles, see docs. Only then you can safely create the two previews and know the app will not crash.

Retrieve name of bluetooth device from rfcomm device services

The context is the following, we have multiple trucks that contains a bluetooth to serial device, we have given each truck bluetooth a unique name to be able to connect to a specific truck.
I use this code to retrieve all the RFComm services :
DeviceInformation.FindAllAsync(RfcommDeviceService.GetDeviceSelector(RfcommServiceId.SerialPort))
The problem is that all the DeviceInformation objects returned contains the name of the RFComm service in the Name property instead of the bluetooth device name. When my project was a Win 8 store app, all was fine since the name property contained the bluetooth device name.
I found that I could create a BluetoothDevice object using the device id returned by the above code, but then the app ask to use the bluetooth device for all devices until I find the good one. I would like to prevent that as it wasn't the case with Win 8 store app.
Second solution I found was to parse the device id of the RFComm service which look like this one
Bluetooth#Bluetooth00:c2:c6:56:b0:61-00:15:be:0f:02:d7#RFCOMM:00000000:{00001101-0000-1000-8000-00805f9b34fb}
to remove everything past "#RFCOMM" and use the DeviceInformation.CreateFromIdAsync() function. This works but I was wondering if there was a cleaner solution to my problem since parsing a string can be a real problem if the string format change.
Is there a way to retrieve the name of the bluetooth device without having to ask to use all bluetooth device until we find it?

You can try with following code to get the name of the Bluetooth device:
var serviceInfoCollection = await DeviceInformation.FindAllAsync(RfcommDeviceService.GetDeviceSelector(RfcommServiceId.SerialPort), new string[] { "System.Devices.AepService.AepId" });
foreach (var serviceInfo in serviceInfoCollection)
{
var deviceInfo = await DeviceInformation.CreateFromIdAsync((string)serviceInfo.Properties["System.Devices.AepService.AepId"]);
System.Diagnostics.Debug.WriteLine($"Device name is: '{deviceInfo.Name}' and Id is: '{deviceInfo.Id}'");
}
The key point here is that Bluetooth device is one type of AssociationEndpoint objects. AEPs usually represent a device discovered over a wireless or network protocol. An AssociationEndpoint object is a child of a single AssociationEndpointContainer object and can contain 0 or more AssociationEndpointService objects. And RFComm service is one AssociationEndpointService that Bluetooth device contains. For more info, please see DeviceInformationKind enumeration and Enumerate devices over a network.
AssociationEndpointService has several properties. One of them is System.Devices.AepService.AepId which represents the identifier of the parent AssociationEndpoint object. So we can use this property to get the Bluetooth device information and once we get the device information, we can get the device name easily. However System.Devices.AepService.AepId property is not a commen property in DeviceInformation. So we need to use DeviceInformation.FindAllAsync(String, IIterable(String)) method to require this additional propertie. For more info, please see Device information properties.

How can i create Flashlight app in uwp C#

I have Lumia 830 and i've tried to create flashlight app in UWP C#. my device Flashlight works great but i don't know why i can't create my own app turn on / off Torch of my phone.
I use Lamp class :
var lamp = await Lamp.GetDefaultAsync();
if (lamp == null)
{
ShowErrorMessage("No Lamp device found");
return;
}
lamp.IsEnabled = true;
when run this code on my phone "lamp" is null and it couldn't find my FlashLED. I've got this code from MSDN.Microsoft.com and thay said
If the returned object is null, the Lamp API is unsupported on the
device. Some devices may not support the Lamp API even if there is a
lamp physically present on the device.
This class doesn't work on my Lumia 830 i don't kno why? :(
also i use this code :
var mediaDev = new MediaCapture();
await mediaDev.InitializeAsync();
var videoDev = mediaDev.VideoDeviceController;
var tc = videoDev.TorchControl;
if (tc.Supported)
{
// But wait, for this to work with Blue camera drivers, we have to Start a recording session
// Create video encoding profile as MP4
var videoEncodingProperties = MediaEncodingProfile.CreateMp4(VideoEncodingQuality.Vga);
// Start Video Recording
var videoStorageFile = await KnownFolders.VideosLibrary.CreateFileAsync("tempVideo.mp4", CreationCollisionOption.GenerateUniqueName);
await mediaDev.StartRecordToStorageFileAsync(videoEncodingProperties, videoStorageFile);
// Turn on Torch
mediaDev.VideoDeviceController.TorchControl.Enabled = true;
}
this code works and my FlashLED turn on but it record video and it take's user SD Card memory.
please help me if you know there is best way to turn on/off Torch or FlashLED.
thanks in advance
Hussein Habibi Juybari

The Lamp API is designed for Windows 10 devices only and you can only use it on devices which support the API. Currently supported devices are 950/950XL, 650, and 550. Older devices will not be updated to support this API. You should fall back to the Windows 8.1 method of turning on flash when you detect that the lamp device is not available on older devices.
From: https://wpdev.uservoice.com/forums/110705/suggestions/15846967

Please test default sample named LampDevice (cf. https://github.com/Microsoft/Windows-universal-samples/tree/master/Samples/LampDevice). Do you have the same behavior ? I just tested on Lumia 930 it works fine. No Lumia 830 to test it.