Question Taking camera snapshot with "TryGetLatestImage"

I have couple of questions regarding how TryGetLatestImage works...

1. I have "TakeSnapshot" method connected with button (onclick). When i click the button first time it doesn't go inside "arCameraManager.TryGetLatestImage(out cameraImage)". Second time it works.

Code (CSharp):

1. private void TakeSnapshot() {
2.             XRCameraImage cameraImage;
3.  
4.             if (arCameraManager.TryGetLatestImage(out cameraImage)) {
5.                 StartCoroutine(ProcessImage(cameraImage));
6.                 cameraImage.Dispose();
7.             }
8.         }
9.  
10.         IEnumerator ProcessImage(XRCameraImage image) {
11.             var request = image.ConvertAsync(new XRCameraImageConversionParams {
12.                 inputRect = new RectInt(0, 0, image.width, image.height),
13.                     outputDimensions = new Vector2Int(image.width, image.height),
14.                     outputFormat = TextureFormat.RGB24,
15.                     transformation = CameraImageTransformation.MirrorY
16.             });
17.  
18.             while (!request.status.IsDone())
19.                 yield return null;
20.  
21.             if (request.status != AsyncCameraImageConversionStatus.Ready) {
22.                 Debug.LogErrorFormat("Request failed with status {0}", request.status);
23.                 request.Dispose();
24.                 yield break;
25.             }
26.  
27.             var rawData = request.GetData<byte>();
28.  
29.             Texture2D imageTexture = new Texture2D(
30.                 request.conversionParams.outputDimensions.x,
31.                 request.conversionParams.outputDimensions.y,
32.                 request.conversionParams.outputFormat,
33.                 false);
34.  
35.             imageTexture.LoadRawTextureData(rawData);
36.             imageTexture.Apply();
37.  
38.             request.Dispose();
39.  
40.             snapshotImage.texture = imageTexture;
41.         }

2. Texture is 640x480 and rotated (landscape instead of portrait). How can i set resolution to native and rotate it?

3. If i use "arCameraManager.frameReceived" resolution is correct, but this is not useful, cause frame is received every frame (i think).

Code (CSharp):

1. private void OnEnable() {
2.             arCameraManager.frameReceived += OnFrameReceived;
3.         }
4.  
5.         private void OnFrameReceived(ARCameraFrameEventArgs obj) {
6.             var tex = obj.textures[0];
7.         }

Help please ... Thank you

 

Bytheway code is from official help: https://docs.unity3d.com/Packages/com.unity.xr.arfoundation@4.0/manual/cpu-camera-image.html
I have "TakeSnapshot" instead of "GetImageAsync"...
I think that TryGetLatestImage is async (it doesn't receive image on the same frame). But if that is true, you must call "GetImageAsync" at least 2 times... Which is wierd.
I'm confused here.

Edit:
I also updated ARFoundation, subsytem and ARCore, and i used:
arCameraManager.TryAcquireLatestCpuImage(out XRCpuImage cameraImage)
... no difference.