UVCC dual camera capture quick example

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
  ~  UVCCamera
  ~  library and sample to access to UVC web camera on non-rooted Android device
  ~
  ~ Copyright (c) 2014-2017 saki t_saki@serenegiant.com
  ~
  ~  Licensed under the Apache License, Version 2.0 (the "License");
  ~  you may not use this file except in compliance with the License.
  ~   You may obtain a copy of the License at
  ~
  ~      http://www.apache.org/licenses/LICENSE-2.0
  ~
  ~   Unless required by applicable law or agreed to in writing, software
  ~   distributed under the License is distributed on an "AS IS" BASIS,
  ~   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  ~   See the License for the specific language governing permissions and
  ~   limitations under the License.
  ~
  ~  All files in the folder are under this Apache License, Version 2.0.
  ~  Files in the libjpeg-turbo, libusb, libuvc, rapidjson folder
  ~  may have a different license, see the respective files.
  -->
<android.support.v4.widget.DrawerLayout
	xmlns:android="http://schemas.android.com/apk/res/android"
	xmlns:tools="http://schemas.android.com/tools" android:id="@+id/drawer_layout"
	android:layout_width="match_parent"
	android:layout_height="match_parent"
>
	<RelativeLayout
		android:id="@+id/RelativeLayout1"
		android:layout_width="match_parent"
		android:layout_height="match_parent"
		android:background="#ffffffff"
		tools:context="com.serenegiant.usbcameratest3.MainActivity"
		tools:ignore="MergeRootFrame">

		<HorizontalScrollView
			android:layout_width="wrap_content"
			android:layout_height="wrap_content"
		>
			<ScrollView
				android:layout_width="wrap_content"
				android:layout_height="wrap_content"
			>
				<LinearLayout
					android:layout_width="wrap_content"
					android:layout_height="wrap_content"
					android:layout_centerInParent="true"
					android:baselineAligned="false"
					android:orientation="vertical">

					<RelativeLayout
						android:id="@+id/camera_layout_L"
						android:layout_width="wrap_content"
						android:layout_height="wrap_content"
						android:layout_weight="1">

						<com.serenegiant.widget.UVCCameraTextureView
							android:id="@+id/camera_view_L"
							android:layout_width="1280px"
							android:layout_height="720px"
							android:layout_centerHorizontal="true"
						/>

						<ImageView
							android:id="@+id/frame_image_L"
							android:layout_width="1280px"
							android:layout_height="720px"
							android:layout_alignBottom="@+id/camera_view_L"
							android:layout_alignLeft="@+id/camera_view_L"
							android:layout_alignRight="@+id/camera_view_L"
							android:layout_alignTop="@+id/camera_view_L"
							android:src="@drawable/border"/>
					</RelativeLayout>

					<RelativeLayout
						android:id="@+id/camera_layout_R"
						android:layout_width="wrap_content"
						android:layout_height="wrap_content"
						android:layout_weight="1">

						<com.serenegiant.widget.UVCCameraTextureView
							android:id="@+id/camera_view_R"
							android:layout_width="1280px"
							android:layout_height="720px"
							android:layout_centerHorizontal="true"
						/>

						<ImageView
							android:id="@+id/frame_image_R"
							android:layout_width="1280px"
							android:layout_height="720px"
							android:layout_alignBottom="@+id/camera_view_R"
							android:layout_alignLeft="@+id/camera_view_R"
							android:layout_alignRight="@+id/camera_view_R"
							android:layout_alignTop="@+id/camera_view_R"
							android:src="@drawable/border"/>
					</RelativeLayout>
				</LinearLayout>

			</ScrollView>
		</HorizontalScrollView>
		<ImageButton
			android:id="@+id/capture_button"
			android:layout_width="@dimen/button_size"
			android:layout_height="@dimen/button_size"
			android:layout_centerVertical="true"
			android:layout_alignParentRight="true"
			android:layout_marginBottom="6dp"
			android:background="@null"
			android:scaleType="centerCrop"
			android:src="@android:drawable/ic_menu_camera"/>
	</RelativeLayout>
	<LinearLayout
		android:layout_width="wrap_content"
		android:layout_height="match_parent"
		android:layout_gravity="left"
		android:background="@color/WHITE"
		android:orientation="vertical"
	>
		<EditText
			android:id="@+id/drawerText"
			android:minWidth="150dp"
			android:layout_width="wrap_content"
			android:layout_height="wrap_content"
			android:hint="description"
			android:text=""
			android:lines="1"
			android:textColor="@color/BLACK"
		/>
	</LinearLayout>
</android.support.v4.widget.DrawerLayout>

MainActivity.java

/*
 *  UVCCamera
 *  library and sample to access to UVC web camera on non-rooted Android device
 *
 * Copyright (c) 2014-2017 saki t_saki@serenegiant.com
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *   You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *   Unless required by applicable law or agreed to in writing, software
 *   distributed under the License is distributed on an "AS IS" BASIS,
 *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *   See the License for the specific language governing permissions and
 *   limitations under the License.
 *
 *  All files in the folder are under this Apache License, Version 2.0.
 *  Files in the libjpeg-turbo, libusb, libuvc, rapidjson folder
 *  may have a different license, see the respective files.
 */

package com.serenegiant.usbcameratest7;

import android.graphics.SurfaceTexture;
import android.hardware.usb.UsbDevice;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.Surface;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnLongClickListener;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.Toast;

import com.serenegiant.common.BaseActivity;
import com.serenegiant.encoder.MediaMuxerWrapper;
import com.serenegiant.usb.CameraDialog;
import com.serenegiant.usb.USBMonitor;
import com.serenegiant.usb.USBMonitor.OnDeviceConnectListener;
import com.serenegiant.usb.USBMonitor.UsbControlBlock;
import com.serenegiant.usbcameracommon.UVCCameraHandler;
import com.serenegiant.widget.CameraViewInterface;
import com.serenegiant.widget.UVCCameraTextureView;

import java.io.File;

/**
 * Show side by side view from two camera.
 * You cane record video images from both camera, but secondarily started recording can not record
 * audio because of limitation of Android AudioRecord(only one instance of AudioRecord is available
 * on the device) now.
 */
public final class MainActivity extends BaseActivity implements CameraDialog.CameraDialogParent {
	private static final boolean DEBUG = true;    // FIXME set false when production
	private static final String TAG = "MainActivity";

	private static final float[] BANDWIDTH_FACTORS = {1.0f, 1.0f};
	private static final int[] RESOLUTION = {1280, 720};

	// for accessing USB and USB camera
	private USBMonitor mUSBMonitor;

	private UVCCameraHandler mHandlerR;
	private CameraViewInterface mUVCCameraViewR;
	private Surface mRightPreviewSurface;

	private UVCCameraHandler mHandlerL;
	private CameraViewInterface mUVCCameraViewL;
	private Surface mLeftPreviewSurface;

	private ImageButton mCaptureButton;

	@Override
	protected void onCreate(final Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		findViewById(R.id.RelativeLayout1).setOnClickListener(mOnClickListener);

		mUVCCameraViewL = (CameraViewInterface) findViewById(R.id.camera_view_L);
		mUVCCameraViewL.setAspectRatio(RESOLUTION[0], RESOLUTION[1]);
		((UVCCameraTextureView) mUVCCameraViewL).setOnClickListener(mOnClickListener);
		mHandlerL = UVCCameraHandler.createHandler(this, mUVCCameraViewL, RESOLUTION[0],
				RESOLUTION[1], BANDWIDTH_FACTORS[0]);

		mUVCCameraViewR = (CameraViewInterface) findViewById(R.id.camera_view_R);
		mUVCCameraViewR.setAspectRatio(RESOLUTION[0], RESOLUTION[1]);
		((UVCCameraTextureView) mUVCCameraViewR).setOnClickListener(mOnClickListener);
		mHandlerR = UVCCameraHandler.createHandler(this, mUVCCameraViewR, RESOLUTION[0],
				RESOLUTION[1], BANDWIDTH_FACTORS[1]);

		mCaptureButton = (ImageButton) findViewById(R.id.capture_button);
		mCaptureButton.setOnClickListener(mOnClickListener);
		mCaptureButton.setVisibility(View.INVISIBLE);
		mUSBMonitor = new USBMonitor(this, mOnDeviceConnectListener);
	}

	@Override
	protected void onStart() {
		super.onStart();
		mUSBMonitor.register();
		if (mUVCCameraViewR != null)
			mUVCCameraViewR.onResume();
		if (mUVCCameraViewL != null)
			mUVCCameraViewL.onResume();
	}

	@Override
	protected void onStop() {
		mHandlerR.close();
		if (mUVCCameraViewR != null)
			mUVCCameraViewR.onPause();
		mHandlerL.close();
		if (mUVCCameraViewL != null)
			mUVCCameraViewL.onPause();
		mCaptureButton.setVisibility(View.INVISIBLE);
		mUSBMonitor.unregister();
		super.onStop();
	}

	@Override
	protected void onDestroy() {
		if (mHandlerR != null) {
			mHandlerR = null;
		}
		if (mHandlerL != null) {
			mHandlerL = null;
		}
		if (mUSBMonitor != null) {
			mUSBMonitor.destroy();
			mUSBMonitor = null;
		}
		mUVCCameraViewR = null;
		mUVCCameraViewL = null;
		mCaptureButton = null;
		super.onDestroy();
	}

	private final OnClickListener mOnClickListener = new OnClickListener() {
		@Override
		public void onClick(final View view) {
			switch (view.getId()) {
				case R.id.camera_view_L:
					if (mHandlerL != null) {
						if (!mHandlerL.isOpened()) {
							CameraDialog.showDialog(MainActivity.this);
						} else {
							mHandlerL.close();
							setCameraButton();
						}
					}
					break;
				case R.id.camera_view_R:
					if (mHandlerR != null) {
						if (!mHandlerR.isOpened()) {
							CameraDialog.showDialog(MainActivity.this);
						} else {
							mHandlerR.close();
							setCameraButton();
						}
					}
					break;
				case R.id.capture_button:
					if (mHandlerL != null && mHandlerR != null) {
						if (mHandlerL.isOpened() && mHandlerR.isOpened()) {
							if (checkPermissionWriteExternalStorage()) {
								if (!mHandlerL.isRecording()) {
									String drawerText = ((EditText)findViewById(R.id.drawerText)).getText().toString();

									if(null == drawerText || drawerText.isEmpty())
										drawerText = "";
									else
										drawerText = "_(" + drawerText + ")";

									final File outputFileL = MediaMuxerWrapper.getCaptureFile(
											Environment.DIRECTORY_DCIM, drawerText + "_L.png");
									final File outputFileR = MediaMuxerWrapper.getCaptureFile(
											Environment.DIRECTORY_DCIM, drawerText + "_R.png");
									mHandlerL.captureStill(outputFileL.toString());
									mHandlerR.captureStill(outputFileR.toString());
								} else {
									mCaptureButton.setColorFilter(0);    // return to default color
									mHandlerL.stopRecording();
									mHandlerR.stopRecording();
								}
							}
						}
					}
					break;
			}
		}
	};

	private final OnLongClickListener mOnLongClickListener = new OnLongClickListener() {
		@Override
		public boolean onLongClick(View v) {
			switch (v.getId()) {
				case R.id.capture_button:
					if (mHandlerL != null && mHandlerR != null) {
						if (mHandlerL.isOpened() && mHandlerR.isOpened()) {
							if (checkPermissionWriteExternalStorage() && checkPermissionAudio()) {
								if (!mHandlerL.isRecording() && !mHandlerR.isRecording()) {
									mCaptureButton.setColorFilter(0xffff0000);    // turn red
									mHandlerL.startRecording();
									mHandlerR.startRecording();
								} else {
									mCaptureButton.setColorFilter(0);    // return to default color
									mHandlerL.stopRecording();
									mHandlerR.stopRecording();
								}
							}
						}
					}
					return true;
			}
			return false;
		}
	};

	private final OnDeviceConnectListener mOnDeviceConnectListener = new OnDeviceConnectListener
			() {
		@Override
		public void onAttach(final UsbDevice device) {
			if (DEBUG) Log.v(TAG, "onAttach:" + device);
			Toast.makeText(MainActivity.this, "USB_DEVICE_ATTACHED", Toast.LENGTH_SHORT).show();

			USBMonitor usbMonitor = getUSBMonitor();
			usbMonitor.requestPermission(device);
		}

		@Override
		public void onConnect(final UsbDevice device, final UsbControlBlock ctrlBlock, final
		boolean createNew) {
			if (DEBUG) Log.v(TAG, "onConnect:" + device);
			if (!mHandlerL.isOpened()) {
				mHandlerL.open(ctrlBlock);
				final SurfaceTexture st = mUVCCameraViewL.getSurfaceTexture();
				mHandlerL.startPreview(new Surface(st));
				runOnUiThread(new Runnable() {
					@Override
					public void run() {
						mCaptureButton.setVisibility(View.VISIBLE);
					}
				});
			} else if (!mHandlerR.isOpened()) {
				mHandlerR.open(ctrlBlock);
				final SurfaceTexture st = mUVCCameraViewR.getSurfaceTexture();
				mHandlerR.startPreview(new Surface(st));
				runOnUiThread(new Runnable() {
					@Override
					public void run() {
						mCaptureButton.setVisibility(View.VISIBLE);
					}
				});
			}
		}

		@Override
		public void onDisconnect(final UsbDevice device, final UsbControlBlock ctrlBlock) {
			if (DEBUG) Log.v(TAG, "onDisconnect:" + device);
			if ((mHandlerL != null) && !mHandlerL.isEqual(device)) {
				queueEvent(new Runnable() {
					@Override
					public void run() {
						mHandlerL.close();
						if (mLeftPreviewSurface != null) {
							mLeftPreviewSurface.release();
							mLeftPreviewSurface = null;
						}
						setCameraButton();
					}
				}, 0);
			} else if ((mHandlerR != null) && !mHandlerR.isEqual(device)) {
				queueEvent(new Runnable() {
					@Override
					public void run() {
						mHandlerR.close();
						if (mRightPreviewSurface != null) {
							mRightPreviewSurface.release();
							mRightPreviewSurface = null;
						}
						setCameraButton();
					}
				}, 0);
			}
		}

		@Override
		public void onDettach(final UsbDevice device) {
			if (DEBUG) Log.v(TAG, "onDettach:" + device);
			Toast.makeText(MainActivity.this, "USB_DEVICE_DETACHED", Toast.LENGTH_SHORT).show();
		}

		@Override
		public void onCancel(final UsbDevice device) {
			if (DEBUG) Log.v(TAG, "onCancel:");
		}
	};

	/**
	 * to access from CameraDialog
	 *
	 * @return
	 */
	@Override
	public USBMonitor getUSBMonitor() {
		return mUSBMonitor;
	}

	@Override
	public void onDialogResult(boolean canceled) {
		if (canceled) {
			runOnUiThread(new Runnable() {
				@Override
				public void run() {
					setCameraButton();
				}
			}, 0);
		}
	}

	private void setCameraButton() {
		runOnUiThread(new Runnable() {
			@Override
			public void run() {
				if ((mHandlerL != null) && !mHandlerL.isOpened() && (mHandlerR != null) &&
						!mHandlerR.isOpened() && (mCaptureButton != null)) {
					mCaptureButton.setVisibility(View.INVISIBLE);
				}
			}
		}, 0);
	}
}