Preview callback

build.gradle

@@ -2,10 +2,10 @@
 
 buildscript {
     repositories {
-        jcenter()
+
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.3.0'
+        classpath 'com.android.tools.build:gradle:2.3.3'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
@@ -14,7 +14,7 @@ buildscript {
 
 allprojects {
     repositories {
-        jcenter()
+        flatDir{ dirs "../test-libs" }
     }
 }
 

demo/src/main/java/com/google/android/cameraview/demo/MainActivity.java

@@ -20,6 +20,8 @@
 import android.app.Dialog;
 import android.content.DialogInterface;
 import android.content.pm.PackageManager;
+import android.graphics.ImageFormat;
+import android.media.Image;
 import android.os.Build;
 import android.os.Bundle;
 import android.os.Environment;
@@ -235,7 +237,11 @@ private Handler getBackgroundHandler() {
     }
 
     private CameraView.Callback mCallback
-            = new CameraView.Callback() {
+            = new CameraView.Callback()
+    {
+        @Override
+        public void onPreviewFrame(CameraView cameraView, byte[] data, int width, int height, int format) {
+        }
 
         @Override
         public void onCameraOpened(CameraView cameraView) {

demo/src/main/res/layout/activity_main.xml

@@ -29,7 +29,9 @@
         android:layout_alignParentStart="true"
         android:layout_alignParentTop="true"
         android:adjustViewBounds="true"
-        android:background="@android:color/black"/>
+        android:background="@android:color/black"
+        app:preferredPreviewFormat="NV21"
+        />
 
     <android.support.v7.widget.Toolbar
         android:id="@+id/toolbar"

library/build.gradle

@@ -38,12 +38,18 @@ android {
     }
 }
 
+
 dependencies {
     compile "com.android.support:support-annotations:$supportLibraryVersion"
     compile "com.android.support:support-v4:$supportLibraryVersion"
 
+
     // Tests
+    testCompile 'org.hamcrest:hamcrest-core:1.3'
     testCompile 'junit:junit:4.12'
+
+    androidTestCompile 'org.hamcrest:hamcrest-core:1.3'
+    androidTestCompile 'junit:junit:4.12'
     androidTestCompile('com.android.support.test:runner:0.5') {
         exclude module: 'support-annotations'
     }

library/src/main/api14/com/google/android/cameraview/Camera1.java

@@ -20,7 +20,9 @@
 import android.graphics.SurfaceTexture;
 import android.hardware.Camera;
 import android.os.Build;
+import android.support.annotation.RequiresApi;
 import android.support.v4.util.SparseArrayCompat;
+import android.util.Log;
 import android.view.SurfaceHolder;
 
 import java.io.IOException;
@@ -36,6 +38,7 @@ class Camera1 extends CameraViewImpl {
     private static final int INVALID_CAMERA_ID = -1;
 
     private static final SparseArrayCompat<String> FLASH_MODES = new SparseArrayCompat<>();
+    private static final String TAG = "Camera1";
 
     static {
         FLASH_MODES.put(Constants.FLASH_OFF, Camera.Parameters.FLASH_MODE_OFF);
@@ -70,15 +73,37 @@ class Camera1 extends CameraViewImpl {
     private int mFlash;
 
     private int mDisplayOrientation;
+    private int mPreviewFormat;
 
-    Camera1(Callback callback, PreviewImpl preview) {
+    Camera.PreviewCallback mPreviewCallback;
+
+
+    Camera1(final Callback callback, PreviewImpl preview) {
         super(callback, preview);
+
+        mPreviewCallback = new Camera.PreviewCallback() {
+            @Override public void onPreviewFrame(byte[] data, Camera camera)
+            {
+                callback.onPreviewFrame( data,
+                        mCameraParameters.getPreviewSize().width,
+                        mCameraParameters.getPreviewSize().height,
+                        mCameraParameters.getPreviewFormat());
+            }
+        };
+
+
         preview.setCallback(new PreviewImpl.Callback() {
             @Override
             public void onSurfaceChanged() {
                 if (mCamera != null) {
                     setUpPreview();
                     adjustCameraParameters();
+
+                    mCamera.setPreviewCallback(mPreviewCallback);
+                }
+                else
+                {
+                    Log.d(TAG, "Cannot set preview callback because mCamera == null");
                 }
             }
         });
@@ -99,16 +124,21 @@ boolean start() {
     @Override
     void stop() {
         if (mCamera != null) {
+            mCamera.setPreviewCallback(null);
             mCamera.stopPreview();
         }
+
         mShowingPreview = false;
         releaseCamera();
     }
 
+
+
     // Suppresses Camera#setPreviewTexture
     @SuppressLint("NewApi")
     void setUpPreview() {
         try {
+
             if (mPreview.getOutputClass() == SurfaceHolder.class) {
                 final boolean needsToStopPreview = mShowingPreview && Build.VERSION.SDK_INT < 14;
                 if (needsToStopPreview) {
@@ -131,6 +161,24 @@ boolean isCameraOpened() {
         return mCamera != null;
     }
 
+
+    @Override
+    void setPreferredPreviewFormat(int imageFormat) {
+        if (mPreviewFormat == imageFormat) {
+            return;
+        }
+        mPreviewFormat = imageFormat;
+        if (isCameraOpened()) {
+            stop();
+            start();
+        }
+    }
+
+    @Override
+    public int getPreferredPreviewFormat() {
+        return mPreviewFormat;
+    }
+
     @Override
     void setFacing(int facing) {
         if (mFacing == facing) {
@@ -334,6 +382,10 @@ void adjustCameraParameters() {
         if (mShowingPreview) {
             mCamera.stopPreview();
         }
+
+        if(mCameraParameters.getSupportedPreviewFormats().contains(getPreferredPreviewFormat())) {
+            mCameraParameters.setPreviewFormat(getPreferredPreviewFormat());
+        }
         mCameraParameters.setPreviewSize(size.getWidth(), size.getHeight());
         mCameraParameters.setPictureSize(pictureSize.getWidth(), pictureSize.getHeight());
         mCameraParameters.setRotation(calcCameraRotation(mDisplayOrientation));

library/src/main/api21/com/google/android/cameraview/Camera2.java

@@ -35,7 +35,9 @@
 import android.util.SparseIntArray;
 import android.view.Surface;
 
+import java.io.ByteArrayOutputStream;
 import java.nio.ByteBuffer;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Set;
 import java.util.SortedSet;
@@ -151,10 +153,44 @@ public void onReady() {
 
     };
 
-    private final ImageReader.OnImageAvailableListener mOnImageAvailableListener
+    private final ImageReader.OnImageAvailableListener mOnPreviewAvailableListener
             = new ImageReader.OnImageAvailableListener() {
 
         @Override
+        public void onImageAvailable(ImageReader reader) {
+            Image image = reader.acquireLatestImage();
+            if (image != null) {
+                try {
+                    ArrayList<byte[]> buffers = new ArrayList<>();
+                    Image.Plane[] planes = image.getPlanes();
+                    if(planes.length == 0)
+                    {return;}
+
+                    //concatenate planes into a single byte array to be compatible with Camera1
+                    for (int i = 0; i < planes.length; i++) {
+                        ByteBuffer buffer = planes[i].getBuffer();
+                        byte[] data = new byte[buffer.remaining()];
+                        buffer.get(data);
+                        buffers.add(data);
+                    }
+                    ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+                    for (int i = 0; i < buffers.size(); i++) {
+                        outputStream.write(buffers.get(i), 0, buffers.get(i).length);
+                    }
+
+                    mCallback.onPreviewFrame(
+                            outputStream.toByteArray(), image.getWidth(), image.getHeight(), image.getFormat()
+                    );
+                } finally {
+                    image.close();
+                }
+            }
+        }
+    };
+
+    private final ImageReader.OnImageAvailableListener mOnImageAvailableListener
+            = new ImageReader.OnImageAvailableListener() {
+        @Override
         public void onImageAvailable(ImageReader reader) {
             try (Image image = reader.acquireNextImage()) {
                 Image.Plane[] planes = image.getPlanes();
@@ -182,6 +218,8 @@ public void onImageAvailable(ImageReader reader) {
 
     private ImageReader mImageReader;
 
+    private ImageReader mPreviewReader;
+
     private final SizeMap mPreviewSizes = new SizeMap();
 
     private final SizeMap mPictureSizes = new SizeMap();
@@ -196,6 +234,9 @@ public void onImageAvailable(ImageReader reader) {
 
     private int mDisplayOrientation;
 
+    private int mPreviewFormat = ImageFormat.YUV_420_888;
+    private int[] mOutputFormats;
+
     Camera2(Callback callback, PreviewImpl preview, Context context) {
         super(callback, preview);
         mCameraManager = (CameraManager) context.getSystemService(Context.CAMERA_SERVICE);
@@ -232,6 +273,12 @@ void stop() {
             mImageReader.close();
             mImageReader = null;
         }
+
+        if(mPreviewReader != null)
+        {
+            mPreviewReader.close();
+            mPreviewReader = null;
+        }
     }
 
     @Override
@@ -256,6 +303,24 @@ int getFacing() {
         return mFacing;
     }
 
+    @Override
+    void setPreferredPreviewFormat(int imageFormat) {
+        if (mPreviewFormat == imageFormat) {
+            return;
+        }
+
+        mPreviewFormat = imageFormat;
+        if (isCameraOpened()) {
+            stop();
+            start();
+        }
+    }
+
+    @Override
+    public int getPreferredPreviewFormat() {
+        return mPreviewFormat;
+    }
+
     @Override
     Set<AspectRatio> getSupportedAspectRatios() {
         return mPreviewSizes.ratios();
@@ -382,8 +447,7 @@ private boolean chooseCameraIdByFacing() {
             mCameraCharacteristics = mCameraManager.getCameraCharacteristics(mCameraId);
             Integer level = mCameraCharacteristics.get(
                     CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL);
-            if (level == null ||
-                    level == CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_LEGACY) {
+            if (level == null ) {
                 return false;
             }
             Integer internal = mCameraCharacteristics.get(CameraCharacteristics.LENS_FACING);
@@ -435,6 +499,8 @@ private void collectCameraInfo() {
         if (!mPreviewSizes.ratios().contains(mAspectRatio)) {
             mAspectRatio = mPreviewSizes.ratios().iterator().next();
         }
+
+        mOutputFormats = map.getOutputFormats();
     }
 
     protected void collectPictureSizes(SizeMap sizes, StreamConfigurationMap map) {
@@ -451,6 +517,29 @@ private void prepareImageReader() {
         mImageReader = ImageReader.newInstance(largest.getWidth(), largest.getHeight(),
                 ImageFormat.JPEG, /* maxImages */ 2);
         mImageReader.setOnImageAvailableListener(mOnImageAvailableListener, null);
+
+
+        if (mPreviewReader != null) {
+            mPreviewReader.close();
+        }
+        Size previewSize = mPreviewSizes.sizes(mAspectRatio).last();
+
+        int fmt = ImageFormat.YUV_420_888;
+        if (mOutputFormats != null) {
+            for (int format : mOutputFormats) {
+                if (format == getPreferredPreviewFormat()) {
+                    fmt = format;
+                    break;
+                }
+            }
+        }
+
+        mPreviewReader = ImageReader.newInstance(   previewSize.getWidth(),
+                                                    previewSize.getHeight(),
+                                                    fmt,
+                                                    2);
+
+        mPreviewReader.setOnImageAvailableListener( mOnPreviewAvailableListener, null );
     }
 
     /**
@@ -478,9 +567,11 @@ void startCaptureSession() {
         mPreview.setBufferSize(previewSize.getWidth(), previewSize.getHeight());
         Surface surface = mPreview.getSurface();
         try {
-            mPreviewRequestBuilder = mCamera.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
+            mPreviewRequestBuilder = mCamera.createCaptureRequest(CameraDevice.TEMPLATE_RECORD);
             mPreviewRequestBuilder.addTarget(surface);
-            mCamera.createCaptureSession(Arrays.asList(surface, mImageReader.getSurface()),
+            mPreviewRequestBuilder.addTarget(mPreviewReader.getSurface());
+
+            mCamera.createCaptureSession( Arrays.asList(surface, mImageReader.getSurface(), mPreviewReader.getSurface()),
                     mSessionCallback, null);
         } catch (CameraAccessException e) {
             throw new RuntimeException("Failed to start camera session");

library/src/main/base/com/google/android/cameraview/CameraViewImpl.java

@@ -16,6 +16,7 @@
 
 package com.google.android.cameraview;
 
+import android.media.Image;
 import android.view.View;
 
 import java.util.Set;
@@ -46,6 +47,9 @@ View getView() {
 
     abstract void setFacing(int facing);
 
+    abstract void setPreferredPreviewFormat(int imageFormat);
+    abstract int getPreferredPreviewFormat();
+
     abstract int getFacing();
 
     abstract Set<AspectRatio> getSupportedAspectRatios();
@@ -77,6 +81,7 @@ interface Callback {
 
         void onPictureTaken(byte[] data);
 
+        void onPreviewFrame(byte[] data, int width, int height, int format);
     }
 
 }