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Questions tagged [previewcallback]

11 questions
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Android KitKat(4.x.x)'s PreviewCallback is must want SurfaceHolder?

I Have a Question. Android KitKat(4.x.x)'s PreviewCallBack is must want SurfaceHolder? Because My Preview project PreviewCallBack is work very well in Android 6.x, 7.0. And it doesn't use SurfaceHolder. But My PreviewProject in KitKat,…
kimjinyam
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Android - OnPreviewFrame not called

This is my cameraPreview I have set the listener in SurfaceChanged. I can see the camera inside the app - yet the OnPreviewFrame is never called. Here is most of the code public class CameraPreview extends SurfaceView implements…
Alon Ben Horin
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Many callback buffers for camera preview

I'm working with camera in Android and I'm using preview callback with byte buffer. If I call the function addCallbackBuffer many times, it will add several buffers. In what order will be used added buffers when the catching frame - in order of…
imported_lis
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How can I add thermal effect to YUV image

After googling a lot. I find a way to change Preview of a single frame. Correct me if i am wrong. camera.setPreviewCallback(new PreviewCallback() callBack let you get the frame of a Camera in byte. Now you can save it or modify it. First of…
Zar E Ahmer
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android camera2 preview lag when getting frame

I am using Android camera2 in order to extract frames in real time in preview mode to stitch them in NDK side(openCv). I use ImageReader surface to get frames, but it is limited to a max frame…
makhco
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onPreviewFrame() not being invoked

I want to continuously receive frames from the camera and manipulate them. Since the manipulation will be a CPU heavy task, i have opened the camera on a separate handler thread so that any callbacks land on that thread as well. However, the problem…
Abdul Wasae
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How to make threads work in Series

I have created a CameraApp. And getting byte[] cameraPreviewCallback in onPreviewFrame(byte byteArray[] , Camera camera) I am converting these byteArray to rgb and doing a lot of stuff too. So It is working slowly. So I think I should get benefit…
Xar-e-ahmer Khan
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Android: mPrevCallback to JPG, results in black pictures

I am trying to capture the preview of the camera on a surfaceview ,to save it as a JPEG in the internal memory. I found some code here on this site, that does mostly I want but saves the image to the SD Card. I changed that, and came up with the…
Herrmann336
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Android Camera dropping frames by of work in the PreviewCallback

For an Android project I have to analyze camera frames real-time. Now I use the ‘android.hardware.Camera.PreviewCallback’ to receive the camera frames. The problem is that while I try to analyze the frames my FPS drops from 30 fps to 15 fps while I…
Epler
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How start SurfaceHolder.Callback() event if Button Clicked?

i tried to start SurfaceCallback of Camera if Button Clicked, but i cannot , if i did Camera.setPreviewCallback() does not invoked although it works in i invoked SurfaceHolder.Callback() from onCreat()method as shown in code below public class…
Error
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Save PreviewFrame as JPEG on external storage (Android)

I am trying to save the preview frames from the camera on the external storage of my device. These are the permissions in my Manifest:
SparklingWater
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