개요: 안드로이드 프로그래밍(자바)을 해서 딥러닝 기술이 적용되는 카메라앱을 만들어봅니다. 그리고 부분별로 소스코드를 분석합니다.
안드로이드 스튜디오를 이용합니다.
먼저, java파일은 해당하는 페이지의 기능을 담당하고 xml파일은 UI를 담당한다고 보시면 되겠습니다.
MainActivity.java를 생성해줍니다.
MainActivity.java
/*
원본 코드
https://github.com/SkyeBeFreeman/SkyeCamera
https://github.com/googlearchive/android-Camera2Basic/blob/master/Application/src/main/java/com/example/android/camera2basic/Camera2BasicFragment.java
수정
webnautes
*/
package com.example.cameraapp;
import android.annotation.TargetApi;
import android.content.ContentResolver;
import android.content.ContentValues;
import android.content.Context;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.ImageFormat;
import android.graphics.Matrix;
import android.hardware.Sensor;
import android.hardware.SensorManager;
import android.hardware.camera2.CameraAccessException;
import android.hardware.camera2.CameraCaptureSession;
import android.hardware.camera2.CameraCharacteristics;
import android.hardware.camera2.CameraDevice;
import android.hardware.camera2.CameraManager;
import android.hardware.camera2.CameraMetadata;
import android.hardware.camera2.CaptureFailure;
import android.hardware.camera2.CaptureRequest;
import android.hardware.camera2.CaptureResult;
import android.hardware.camera2.TotalCaptureResult;
import android.hardware.camera2.params.StreamConfigurationMap;
import android.media.ExifInterface;
import android.media.Image;
import android.media.ImageReader;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.os.HandlerThread;
import androidx.annotation.NonNull;
import androidx.core.app.ActivityCompat;
import androidx.appcompat.app.AppCompatActivity;
import android.provider.MediaStore;
import android.util.DisplayMetrics;
import android.util.Log;
import android.util.Size;
import android.util.SparseIntArray;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.WindowManager;
import android.widget.FrameLayout;
import android.widget.ImageButton;
import android.widget.Toast;
import java.io.OutputStream;
import java.nio.ByteBuffer;
import java.util.Arrays;
public class MainActivity extends AppCompatActivity{
private SurfaceView mSurfaceView;
private SurfaceHolder mSurfaceViewHolder;
private Handler mHandler;
private ImageReader mImageReader;
private CameraDevice mCameraDevice;
private CaptureRequest.Builder mPreviewBuilder;
private CameraCaptureSession mSession;
private int mDeviceRotation;
private Sensor mAccelerometer;
private Sensor mMagnetometer;
private SensorManager mSensorManager;
private DeviceOrientation deviceOrientation;
int mDSI_height, mDSI_width;
private static final SparseIntArray ORIENTATIONS = new SparseIntArray();
static {
ORIENTATIONS.append(ExifInterface.ORIENTATION_NORMAL, 0);
ORIENTATIONS.append(ExifInterface.ORIENTATION_ROTATE_90, 90);
ORIENTATIONS.append(ExifInterface.ORIENTATION_ROTATE_180, 180);
ORIENTATIONS.append(ExifInterface.ORIENTATION_ROTATE_270, 270);
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// 상태바를 안보이도록 합니다.
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
// 화면 켜진 상태를 유지합니다.
getWindow().setFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON,
WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
setContentView(R.layout.activity_main);
ImageButton button = findViewById(R.id.take_photo);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
takePicture();
}
});
mSurfaceView = findViewById(R.id.surfaceView);
mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mMagnetometer = mSensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD);
deviceOrientation = new DeviceOrientation();
initSurfaceView();
}
@Override
protected void onResume() {
super.onResume();
mSensorManager.registerListener(deviceOrientation.getEventListener(), mAccelerometer, SensorManager.SENSOR_DELAY_UI);
mSensorManager.registerListener(deviceOrientation.getEventListener(), mMagnetometer, SensorManager.SENSOR_DELAY_UI);
}
@Override
protected void onPause() {
super.onPause();
mSensorManager.unregisterListener(deviceOrientation.getEventListener());
}
public void initSurfaceView() {
DisplayMetrics displayMetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
mDSI_height = displayMetrics.heightPixels;
mDSI_width = displayMetrics.widthPixels;
mSurfaceViewHolder = mSurfaceView.getHolder();
mSurfaceViewHolder.addCallback(new SurfaceHolder.Callback() {
@Override
public void surfaceCreated(SurfaceHolder holder) {
initCameraAndPreview();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
if (mCameraDevice != null) {
mCameraDevice.close();
mCameraDevice = null;
}
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
});
}
@TargetApi(19)
public void initCameraAndPreview() {
HandlerThread handlerThread = new HandlerThread("CAMERA2");
handlerThread.start();
mHandler = new Handler(handlerThread.getLooper());
Handler mainHandler = new Handler(getMainLooper());
try {
String mCameraId = "" + CameraCharacteristics.LENS_FACING_FRONT; // 후면 카메라 사용
CameraManager mCameraManager = (CameraManager) this.getSystemService(Context.CAMERA_SERVICE);
CameraCharacteristics characteristics = mCameraManager.getCameraCharacteristics(mCameraId);
StreamConfigurationMap map = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);
Size largestPreviewSize = map.getOutputSizes(ImageFormat.JPEG)[0];
Log.i("LargestSize", largestPreviewSize.getWidth() + " " + largestPreviewSize.getHeight());
setAspectRatioTextureView(largestPreviewSize.getHeight(),largestPreviewSize.getWidth());
mImageReader = ImageReader.newInstance(largestPreviewSize.getWidth(), largestPreviewSize.getHeight(), ImageFormat.JPEG,/*maxImages*/7);
mImageReader.setOnImageAvailableListener(mOnImageAvailableListener, mainHandler);
if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
return;
}
mCameraManager.openCamera(mCameraId, deviceStateCallback, mHandler);
} catch (CameraAccessException e) {
Toast.makeText(this, "카메라를 열지 못했습니다.", Toast.LENGTH_SHORT).show();
}
}
private ImageReader.OnImageAvailableListener mOnImageAvailableListener = new ImageReader.OnImageAvailableListener() {
@Override
public void onImageAvailable(ImageReader reader) {
Image image = reader.acquireNextImage();
ByteBuffer buffer = image.getPlanes()[0].getBuffer();
byte[] bytes = new byte[buffer.remaining()];
buffer.get(bytes);
final Bitmap bitmap = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
new SaveImageTask().execute(bitmap);
}
};
private CameraDevice.StateCallback deviceStateCallback = new CameraDevice.StateCallback() {
@Override
public void onOpened(CameraDevice camera) {
mCameraDevice = camera;
try {
takePreview();
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
@Override
public void onDisconnected(@NonNull CameraDevice camera) {
if (mCameraDevice != null) {
mCameraDevice.close();
mCameraDevice = null;
}
}
@Override
public void onError(CameraDevice camera, int error) {
Toast.makeText(MainActivity.this, "카메라를 열지 못했습니다.", Toast.LENGTH_SHORT).show();
}
};
public void takePreview() throws CameraAccessException {
mPreviewBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
mPreviewBuilder.addTarget(mSurfaceViewHolder.getSurface());
mCameraDevice.createCaptureSession(Arrays.asList(mSurfaceViewHolder.getSurface(), mImageReader.getSurface()), mSessionPreviewStateCallback, mHandler);
}
private CameraCaptureSession.StateCallback mSessionPreviewStateCallback = new CameraCaptureSession.StateCallback() {
@Override
public void onConfigured(@NonNull CameraCaptureSession session) {
mSession = session;
try {
mPreviewBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
mPreviewBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH);
mSession.setRepeatingRequest(mPreviewBuilder.build(), null, mHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
@Override
public void onConfigureFailed(@NonNull CameraCaptureSession session) {
Toast.makeText(MainActivity.this, "카메라 구성 실패", Toast.LENGTH_SHORT).show();
}
};
private CameraCaptureSession.CaptureCallback mSessionCaptureCallback = new CameraCaptureSession.CaptureCallback() {
@Override
public void onCaptureCompleted(CameraCaptureSession session, CaptureRequest request, TotalCaptureResult result) {
mSession = session;
unlockFocus();
}
@Override
public void onCaptureProgressed(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull CaptureResult partialResult) {
mSession = session;
}
@Override
public void onCaptureFailed(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull CaptureFailure failure) {
super.onCaptureFailed(session, request, failure);
}
};
public void takePicture() {
try {
CaptureRequest.Builder captureRequestBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);//用来设置拍照请求的request
captureRequestBuilder.addTarget(mImageReader.getSurface());
captureRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
captureRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH);
// 화면 회전 안되게 고정시켜 놓은 상태에서는 아래 로직으로 방향을 얻을 수 없어서
// 센서를 사용하는 것으로 변경
//deviceRotation = getResources().getConfiguration().orientation;
mDeviceRotation = ORIENTATIONS.get(deviceOrientation.getOrientation());
Log.d("@@@", mDeviceRotation+"");
captureRequestBuilder.set(CaptureRequest.JPEG_ORIENTATION, mDeviceRotation);
CaptureRequest mCaptureRequest = captureRequestBuilder.build();
mSession.capture(mCaptureRequest, mSessionCaptureCallback, mHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
public Bitmap getRotatedBitmap(Bitmap bitmap, int degrees) throws Exception {
if(bitmap == null) return null;
if (degrees == 0) return bitmap;
Matrix m = new Matrix();
m.setRotate(degrees, (float) bitmap.getWidth() / 2, (float) bitmap.getHeight() / 2);
return Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), m, true);
}
/**
* Unlock the focus. This method should be called when still image capture sequence is
* finished.
*/
private void unlockFocus() {
try {
// Reset the auto-focus trigger
mPreviewBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER,
CameraMetadata.CONTROL_AF_TRIGGER_CANCEL);
mPreviewBuilder.set(CaptureRequest.CONTROL_AE_MODE,
CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH);
mSession.capture(mPreviewBuilder.build(), mSessionCaptureCallback,
mHandler);
// After this, the camera will go back to the normal state of preview.
mSession.setRepeatingRequest(mPreviewBuilder.build(), mSessionCaptureCallback,
mHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
//출처 - https://codeday.me/ko/qa/20190310/39556.html
/**
* A copy of the Android internals insertImage method, this method populates the
* meta data with DATE_ADDED and DATE_TAKEN. This fixes a common problem where media
* that is inserted manually gets saved at the end of the gallery (because date is not populated).
* @see android.provider.MediaStore.Images.Media#insertImage(ContentResolver, Bitmap, String, String)
*/
public static final String insertImage(ContentResolver cr,
Bitmap source,
String title,
String description) {
ContentValues values = new ContentValues();
values.put(MediaStore.Images.Media.TITLE, title);
values.put(MediaStore.Images.Media.DISPLAY_NAME, title);
values.put(MediaStore.Images.Media.DESCRIPTION, description);
values.put(MediaStore.Images.Media.MIME_TYPE, "image/jpeg");
// Add the date meta data to ensure the image is added at the front of the gallery
values.put(MediaStore.Images.Media.DATE_ADDED, System.currentTimeMillis());
values.put(MediaStore.Images.Media.DATE_TAKEN, System.currentTimeMillis());
Uri url = null;
String stringUrl = null; /* value to be returned */
try {
url = cr.insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
if (source != null) {
OutputStream imageOut = cr.openOutputStream(url);
try {
source.compress(Bitmap.CompressFormat.JPEG, 50, imageOut);
} finally {
imageOut.close();
}
} else {
cr.delete(url, null, null);
url = null;
}
} catch (Exception e) {
if (url != null) {
cr.delete(url, null, null);
url = null;
}
}
if (url != null) {
stringUrl = url.toString();
}
return stringUrl;
}
private class SaveImageTask extends AsyncTask<Bitmap, Void, Void> {
@Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
Toast.makeText(MainActivity.this, "사진을 저장하였습니다.", Toast.LENGTH_SHORT).show();
}
@Override
protected Void doInBackground(Bitmap... data) {
Bitmap bitmap = null;
try {
bitmap = getRotatedBitmap(data[0], mDeviceRotation);
} catch (Exception e) {
e.printStackTrace();
}
insertImage(getContentResolver(), bitmap, ""+System.currentTimeMillis(), "");
return null;
}
}
// 출처 https://stackoverflow.com/a/43516672
private void setAspectRatioTextureView(int ResolutionWidth , int ResolutionHeight )
{
if(ResolutionWidth > ResolutionHeight){
int newWidth = mDSI_width;
int newHeight = ((mDSI_width * ResolutionWidth)/ResolutionHeight);
updateTextureViewSize(newWidth,newHeight);
}else {
int newWidth = mDSI_width;
int newHeight = ((mDSI_width * ResolutionHeight)/ResolutionWidth);
updateTextureViewSize(newWidth,newHeight);
}
}
private void updateTextureViewSize(int viewWidth, int viewHeight) {
Log.d("@@@", "TextureView Width : " + viewWidth + " TextureView Height : " + viewHeight);
mSurfaceView.setLayoutParams(new FrameLayout.LayoutParams(viewWidth, viewHeight));
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<SurfaceView
android:id="@+id/surfaceView"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
<ImageButton
android:id="@+id/take_photo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal|bottom"
android:src="@android:drawable/ic_menu_camera"
/>
</FrameLayout>
