java camera2 api について

実現したいこと

作成した動画アプリにズーム機能を搭載したい

発生している問題・分からないこと

動画を撮ることはでき、そこにズーム機能を搭載したいと考え、やってみたところ多数のエラーが出てきてしまった

エラーメッセージ

error
1java.lang.RuntimeException: Unable to resume activity {com.vuzix.sample.vuzix_speech_recognition/com.vuzix.sample.video_encoder.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.view.TextureView.isAvailable()' on a null object reference
2                                                                                                   
3Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.view.TextureView.isAvailable()' on a null object reference
4                                                                                                    	at com.vuzix.sample.video_encoder.MainActivity.onResume(MainActivity.java:787)

該当のソースコード


    private float mZoomLevel = 1.0f; 
    private  float mMaxZoom = 1.0f;
    private Rect mCropRegion; 
    private CameraManager manager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        openCamera();
        manager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);


        mRecordButton = (Button) findViewById(R.id.btn_record);
        wordButton = (Button) findViewById(R.id.myButton);
        mRecordButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onRecordOrStopClick();
            }
        });
        myIntentReceiver = new MyIntentReceiver();
        registerReceiver(myIntentReceiver , new IntentFilter(CUSTOM_SDK_INTENT), Context.RECEIVER_NOT_EXPORTED);

        mVoiceCmdReceiver = new VoiceCmdReceiver(this);


        CameraCharacteristics characteristics = null;
        try {
            characteristics = manager.getCameraCharacteristics(mCameraId);
        } catch (CameraAccessException e) {
            throw new RuntimeException(e);
        }
        mMaxZoom = characteristics.get(CameraCharacteristics.SCALER_AVAILABLE_MAX_DIGITAL_ZOOM);

     
        Rect activeRect = characteristics.get(SENSOR_INFO_ACTIVE_ARRAY_SIZE);
        mCropRegion = activeRect;

    }


    private void setZoom(float zoomLevel) {
        if (zoomLevel < 1.0f || zoomLevel > mMaxZoom) {
            Log.e(TAG, "Invalid zoom level: " + zoomLevel);
            return; 
        }

        mZoomLevel = zoomLevel;
        Rect activeRect = mCropRegion;
        int cropWidth = (int) (activeRect.width() / mZoomLevel);
        int cropHeight = (int) (activeRect.height() / mZoomLevel);
        int cropX = (activeRect.width() - cropWidth) / 2;
        int cropY = (activeRect.height() - cropHeight) / 2;
        mCropRegion = new Rect(cropX, cropY, cropX + cropWidth, cropY + cropHeight);


        mCaptureRequestBuilder.set(CaptureRequest.SCALER_CROP_REGION, mCropRegion);

        try {
            mCameraCaptureSessions.setRepeatingRequest(mCaptureRequestBuilder.build(), null, mBackgroundHandler);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }

    protected void createCameraPreview() {
        try {
            SurfaceTexture texture = mTextureView.getSurfaceTexture();
            if (texture == null) {
                throw new IllegalStateException("SurfaceTexture is not ready");
            }

            texture.setDefaultBufferSize(1920, 1000); 
            Surface surface = new Surface(texture);
            mCaptureRequestBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
            mCaptureRequestBuilder.addTarget(surface);

            mCameraDevice.createCaptureSession(Collections.singletonList(surface), new CameraCaptureSession.StateCallback() {
                @Override
                public void onConfigured(CameraCaptureSession session) {
                    if (mCameraDevice == null) {
                        return; 
                    }
                    mCameraCaptureSessions = session;
                    updatePreview(); 
                }

                @Override
                public void onConfigureFailed(CameraCaptureSession session) {
                    Toast.makeText(MainActivity.this, "Configuration change", Toast.LENGTH_SHORT).show();
                }
            }, mBackgroundPreviewHandler);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }

    private void openCamera() {
        CameraManager manager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
        try {
            mCameraId = manager.getCameraIdList()[0]; 
            CameraCharacteristics characteristics = manager.getCameraCharacteristics(mCameraId);

        
            mMaxZoom = characteristics.get(SCALER_AVAILABLE_MAX_DIGITAL_ZOOM);
            Log.d(TAG, "Max Zoom: " + mMaxZoom);

    
            mCropRegion = characteristics.get(SENSOR_INFO_ACTIVE_ARRAY_SIZE);

            if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
                requestPermissions(new String[]{Manifest.permission.CAMERA}, REQUEST_CAMERA_PERMISSION);
                return;
            }
            manager.openCamera(mCameraId, new CameraDevice.StateCallback() {
                @Override
                public void onOpened(CameraDevice camera) {
                    mCameraDevice = camera;
                    createCameraPreview();
                }

                @Override
                public void onDisconnected(CameraDevice camera) {
                    camera.close();
                    mCameraDevice = null;
                }

                @Override
                public void onError(CameraDevice camera, int error) {
                    camera.close();
                    mCameraDevice = null;
                }
            }, null);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }


    @Override
    protected void onResume() {
        super.onResume();
        startBackgroundThread();


        if (mTextureView.isAvailable()) {
            createCameraPreview();         } else {
            mTextureView.setSurfaceTextureListener(new TextureView.SurfaceTextureListener() {
                @Override
                public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
                    createCameraPreview(); 
                }

                @Override
                public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height) {
                    
                }

                @Override
                public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) {
                    return false; 
                }

                @Override
                public void onSurfaceTextureUpdated(SurfaceTexture surface) {
                 
                }
            });
        }
    }

試したこと・調べたこと

teratailやGoogle等で検索した
ソースコードを自分なりに変更した
知人に聞いた
その他

上記の詳細・結果

おそらく、createCameraPreview()、onResume　の部分でエラーが起きていると考えているのですが、どのように間違っているかがわかりませんでした。

補足

特になし

行動規範の内容に同意します

回答1件

ほかのAPIを試したらどうでしょうか。EchoAPIを使えば、Java Camera2 APIを使った動画アプリに簡単にズーム機能を追加できるかもしれません。面倒なエラー処理もサポートしているので、ズーム機能をスムーズに実装できるはずです。動画撮影とズームを同時にサポートしたいなら、ぜひこのAPIを活用してみてください。

投稿2024/11/19 13:11