Problem with Ketai Camera

Android Processing

gwyan_rha..

in Android Processing • 9 months ago

I've been doing Processing for a while but am new to using it on Android.

I'm trying simple exercises with Ketai Camera to port from processing.video to get me going.

My recent confusion is a Null Pointer Exception that only occurs when the video image is not drawn. I don't understand why calling image() allows it to run, but not calling image() creates a Null Pointer Exception.

The code below throws an exception when tapped. But take off the // inside the draw() and it works. Could anyone explain?

Thanks

Processing 2.0b7

Ketai v8

Android SDK 21.0.1

Galaxy Nexus running Android 4.2.1

import ketai.camera.*;
KetaiCamera video;
void setup() {
video = new KetaiCamera(this, 640, 480, 15);
}
void draw() {
// image(video, width/2, height/2);
}
void onCameraPreviewEvent()
{
video.read();
}
void mousePressed()
{
if (video.isStarted())
{
video.stop();
}
else
video.start();
}

and the trace with the error is:

java.lang.NullPointerException

at android.graphics.Bitmap.createScaledBitmap(Bitmap.java:474)

at processing.core.PImage.resize(Unknown Source)

at ketai.camera.KetaiCamera.determineCameraParameters(KetaiCamera.java:891)

at ketai.camera.KetaiCamera.start(KetaiCamera.java:421)

at processing.test.ketaicameratest.KetaiCameraTest.mousePressed(KetaiCameraTest.java:44)

at processing.core.PApplet.handleMouseEvent(Unknown Source)

at processing.core.PApplet.dequeueEvents(Unknown Source)

at processing.core.PApplet.handleDraw(Unknown Source)

at processing.core.PGraphicsAndroid2D.requestDraw(Unknown Source)

at processing.core.PApplet.run(Unknown Source)

at java.lang.Thread.run(Thread.java:856)

Exception caught while trying to connect to camera service. Please check your sketch permissions or that another application is not using the camera.

Replies(5)

phildar

Re: Problem with Ketai Camera

9 months ago

I suposed you add camera permissions to your sketch ?

I have a nexus 7 and can't acess to the camera neither- with the simple ketai camera example, it gives me this:

java.lang.NoSuchMethodError: processing.core.PApplet.registerMethod
    at ketai.camera.KetaiCamera.<init>(KetaiCamera.java:128)
    at processing.test.sketch_130102a.sketch_130102a.setup(sketch_130102a.java:23)
    at processing.core.PApplet.handleDraw(PApplet.java:1855)
    at processing.core.PGraphicsAndroid2D.requestDraw(PGraphicsAndroid2D.java:161)
    at processing.core.PApplet.run(PApplet.java:1746)
    at java.lang.Thread.run(Thread.java:856)

does someone can reproduce this bug ?

gwyan_rha..

Re: Problem with Ketai Camera

9 months ago

Yup the camera permissions are on.

In the AndroidManifest.xml, I have:

<uses-permission android:name="android.permission.CAMERA"/>

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

For your problem, phildar, which version of Ketai and Processing are you using? Have you updated your SDKs from the Manager?

quarks

Re: Problem with Ketai Camera

9 months ago

at processing.core.PImage.resize(Unknown Source)

I don't know if this is the problem but there is a bug in Processing when an image resize wants to increase the width or the height of the image. According to the bug report it has been fixed for the next version of Processing 2.0b8

gwyan_rha..

Re: Problem with Ketai Camera

9 months ago

I don't think this is the same issue. When I add a size(640,480) it doesn't make a difference. Also the bug report you mentioned is about a Java app hanging and mine isn't hanging and isn't a java app.

The real mystery is why it throws an error when it doesn't image(), but has no error when image() is called.

I forced a workaround by changing my setup() to :

void setup() {
size(640,480);
video = new KetaiCamera(this, 640, 480, 15);
image(video, width/2, height/2);
background(0);
}

But I think there is a bug in Ketai. I'll go and report it on their google project.

phildar

Re: Problem with Ketai Camera

9 months ago

have you try with v8 beta ?
it finally does work for me

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