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Xamarin forms Android SurfaceView - still video image left behind

In my Xamarin forms Android app, I play videos in view 1 and 16 in a matrix of 16 views using Android SurfaceView integrating with third-party video SDK, see screenshot below. Then I switch to 4 views. On switching, I stopped both videos first and then resume playing. It still plays video in view 1 which is correct. But it also shows a still video image left behind (from previous view 16). Th surface view of this image should have been removed. What could be the cause of the image?
I can clear a video or image and detach the camera using the following code. We do have such a command button Clear All.
public int ClearVideo(int cameraIndex)
{
if (App.CameraToViewHolderDictionary.ContainsKey(cameraIndex))
{
var surfaceHolder = (ISurfaceHolder)App.CameraToViewHolderDictionary[cameraIndex];
if (surfaceHolder != null/* && surfaceHolder.Surface.IsValid*/)
{
surfaceHolder.SetFormat(Format.Transparent);
surfaceHolder.SetFormat(Format.Opaque);
}
}
_videoViewModel.DetachCamera(cameraIndex);
return 0;
}
However this code shouldn't be required when changing the size of matrix views. Please suggest a way to get rid of the image left behind. Thank you.
I understand that this may not be an issue of Xamarin forms. Please note that the app works on some Android versions such as Pixel 3 or emulators such as bluestacks.

Are Somebody knows how to rotate liveviewOrientation in Sony Camera remote API

I'm using the Sony Camera API for taking a picture remotely, but when I rotate the camera streaming image is still vertical. API ver. is 2.40. I checked the Reference of API but there is nothing about orientation of live view

Look to api getevent (pooling or callback) , you will see a liveviewOrientation value in the result.
{
"type":"liveviewOrientation",
"liveviewOrientation":"90"
}
Then you have to rotate your output stream.
It's device dependant
Rotate:
Read the stream, look for Common Header to decode "Packet",then extract JPEG image from one "Packet",decode it.
Rotate the image according to liveviewOrientation, then show it to your display.

Unity canvas scaler hiding animations in high resolution display

I instantiate the following gameObject, which contains an Animator with the mode "always animate" on, the animation goes for 340ms, after that time I destroy the gameObject.
The gameObject Inspector properties:
I instantiate it using the following code:
instancia = (Instantiate(cardAnimation, new Vector3(0, 0, 0), Quaternion.identity) as GameObject).GetComponent<Image>();
instancia.rectTransform.SetParent(transform);
StartCoroutine(KillOnAnimationEnd());
Here is the Coroutine:
private IEnumerator KillOnAnimationEnd()
{
yield return new WaitForSeconds(0.34f);
DestroyImmediate(instancia);
}
Here is how the animation looks like when simulating in Unity (PC-Windows):
But on android after I open the chest it waits 340ms with nothing happening and then show the information above, does this have something to do with the plataform or is some unity or perhaps code related issue?
NOTE: I also have another animation in another scene that is just a already instantiated gameObject in the Hierarchy with always animated on and it works on Android.
--EDIT--
So I have ran the newest version of the app in a emulator which is almost about 1080x480 and the animation showed just as the PC, also running on a 720p smartphone did the job, the only problem I'm still having is with my QuadHD resolution from Galaxy S6, everything else shows but the animation, I have even tried making the animation run without any script so it runs in a loop, but it doesn't show up in galaxy screen.
Given the news about the issue I think this might change a little bit the perspective of answers and perhaps help someone else solve the same problem in the future.

Okay, figured out the problem, its something to do with "rotation" in animations using Unity3D in 2D mode, gonna be reporting it form Unity so it is fixed.
The solution: Animate your UI only using scale/position, if used rotation it will not show on high resolution display.

I am pretty sure your WaitForSeconds(0.34f) is not working properly because there is no thing such as yield keyword in Java. I recommend you to use a invoke method instead to call your method that destroys your GameObject.

Is this a Digital Compass or Unity limitation?

I'm interested in AR applications of mobile devices and naturally I would like to make better use of the compass.
The only issue I've been having to work against isn't how twitchy the compass is. (Angular Smoothing seems to solve this issue just fine) My main issue is that when the device is held Vertical the compass values start freaking out. Causing an on screen compass to flip about all over the place. I don't have a lot of experience with mobile application development so I'm not sure what would be causing this issue, if its a Unity issue or if its just a limitation of the digital compass. I know other apps do seem to be able to use the compass fine in any orientation, but this is all stupidly new to me.
I've definitely tried moving the phone in a figure of 8. The device I have to play around with is a Nexus 4.
using UnityEngine;
using System.Collections;
public class Compass : MonoBehaviour {
// Use this for initialization
void Start () {
Input.location.Start ();
Input.compass.enabled = true;
}
// Update is called once per frame
void Update ()
{
var heading = Input.compass.trueHeading;
transform.eulerAngles = new Vector3 (0, 0, heading);
}
}

Preamble :)
First of, I'm not an expert (unfortunately) in subjects that I will talk about. But still, I've decided to share my thoughts.
Theory
The problem can be generalized in the following way. You want to have some continuous function that takes a 3D vector (which is device orientation in your case) and returns another vector that is orthogonal to original vector. Theory says (see hairy ball theorem) that for some arguments that function will return zero vectors. In case when such a function is compass, zero vectors are returned when device is oriented vertical (and this fells quite natural if you have ever used an ordinary compass).
Practice
Sometimes you want your app to tell which side of the world does phone back (rear camera) is pointing to.
Or maybe even you want combined approach:
If the phone is oriented flat, show what is the phone's top pointing to.
If the phone is oriented vertical, show what is the phone's back pointing to.
In both cases you need to use gyroscope in addition to compass.

Android Camera.takePicture - Possible to disable shutter sound and preview surface?

I am working on an app that will allow a user to take quick click and forget snapshots. Most of the app is done except for the camera working that way I would like. Right now I have the camera working but I can't seem to find a way to disable the shutter sound and I cant find a way to disable displaying the preview. I was able to cover the preview up with a control but I would rather just not have it displayed if possible.
To sum things up, these are the items that I would like to disable while utilizing the built in Camera controls.
Shutter sound
Camera screen display
Image preview onPictureTaken
Does anyone know of a resource that could point me in the right direction, I would greatly appreciate it. I have been following CommonsWare's example from this sample fairly closely.
Thank you.

This is actually a property in the build.prop of a phone. I'm unsure if its possible to change this. Unless you completely override it and use your own camera code. Using what you can that is available in the SDK.
Take a look at this:
CameraService.cpp
. . .
CameraService::Client::Client(const sp<CameraService>& cameraService,
const sp<ICameraClient>& cameraClient,
const sp<CameraHardwareInterface>& hardware,
int cameraId, int cameraFacing, int clientPid) {
mPreviewCallbackFlag = FRAME_CALLBACK_FLAG_NOOP;
mOrientation = getOrientation(0, mCameraFacing == CAMERA_FACING_FRONT);
mOrientationChanged = false;
cameraService->setCameraBusy(cameraId);
cameraService->loadSound();
LOG1("Client::Client X (pid %d)", callingPid)
}
void CameraService::loadSound() {
Mutex::Autolock lock(mSoundLock);
LOG1("CameraService::loadSound ref=%d", mSoundRef);
if (mSoundRef++) return;
mSoundPlayer[SOUND_SHUTTER] = newMediaPlayer("/system/media/audio/ui/camera_click.ogg");
mSoundPlayer[SOUND_RECORDING] = newMediaPlayer("/system/media/audio/ui/VideoRecord.ogg");
}
As can be noted, the click sound is started without your interaction.
This is the service used in the Gingerbread Source code.
The reason they DON'T allow this is because it is illegal is some countries. Only way to achieve what you want is to have a custom ROM.
Update
If what being said here: http://androidforums.com/t-mobile-g1/6371-camera-shutter-sound-effect-off.html
still applies, then you could write a timer that turns off the sound (Silent Mode) for a couple of seconds and then turn it back on each time you take a picture.

You may use the data from the preview callback using a function to save it at a picture on some type of trigger such as a button, using onclick listener. you could compress the image to jpeg or png. In this way, there no shutterCallback to be implemented. and therefore you can play any sound you want or none when taking a picture.

You can effectively hide the preview surface by giving it dimensions of 1p in the xml file (I found an example the said 0p but for some reason that was giving me errors).
It may be illegal to have a silent shutter in some places, but it doesn't appear that the US is such a place, as my HTC One gives me an option to silence it, and in fact, since Android 4.2 you can do this:
Camera.CameraInfo info=new Camera.CameraInfo();
if (info.canDisableShutterSound) {
camera.enableShutterSound(false);
}