我正在测试可拍摄高质量图像的相机应用程序。我希望将捕获的图像保存在移动存储器（内部或外部）中，以检查图像的细节。
我使用以下代码捕获图像。
import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.design.widget.BottomSheetBehavior;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewTreeObserver;
import android.view.WindowManager;
import android.widget.Toast;
import com.otaliastudios.cameraview.CameraListener;
import com.otaliastudios.cameraview.CameraLogger;
import com.otaliastudios.cameraview.CameraOptions;
import com.otaliastudios.cameraview.CameraView;
import com.otaliastudios.cameraview.SessionType;
import com.otaliastudios.cameraview.Size;
import java.io.File;
public class CameraActivity extends AppCompatActivity implements View.OnClickListener, ControlView.Callback {
private CameraView camera;
private ViewGroup controlPanel;
private boolean mCapturingPicture;
private boolean mCapturingVideo;
// To show stuff in the callback
private Size mCaptureNativeSize;
private long mCaptureTime;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_HARDWARE_ACCELERATED,
WindowManager.LayoutParams.FLAG_HARDWARE_ACCELERATED);
setContentView(R.layout.activity_camera);
CameraLogger.setLogLevel(CameraLogger.LEVEL_VERBOSE);
camera = findViewById(R.id.camera);
camera.addCameraListener(new CameraListener() {
public void onCameraOpened(CameraOptions options) { onOpened(); }
public void onPictureTaken(byte[] jpeg) { onPicture(jpeg); }
@Override
public void onVideoTaken(File video) {
super.onVideoTaken(video);
onVideo(video);
}
});
findViewById(R.id.edit).setOnClickListener(this);
findViewById(R.id.capturePhoto).setOnClickListener(this);
findViewById(R.id.captureVideo).setOnClickListener(this);
findViewById(R.id.toggleCamera).setOnClickListener(this);
controlPanel = findViewById(R.id.controls);
ViewGroup group = (ViewGroup) controlPanel.getChildAt(0);
Control[] controls = Control.values();
for (Control control : controls) {
ControlView view = new ControlView(this, control, this);
group.addView(view, ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.WRAP_CONTENT);
}
controlPanel.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
BottomSheetBehavior b = BottomSheetBehavior.from(controlPanel);
b.setState(BottomSheetBehavior.STATE_HIDDEN);
}
});
}
private void message(String content, boolean important) {
int length = important ? Toast.LENGTH_LONG : Toast.LENGTH_SHORT;
Toast.makeText(this, content, length).show();
}
private void onOpened() {
ViewGroup group = (ViewGroup) controlPanel.getChildAt(0);
for (int i = 0; i < group.getChildCount(); i++) {
ControlView view = (ControlView) group.getChildAt(i);
view.onCameraOpened(camera);
}
}
private void onPicture(byte[] jpeg) {
mCapturingPicture = false;
long callbackTime = System.currentTimeMillis();
if (mCapturingVideo) {
message("Captured while taking video. Size="+mCaptureNativeSize, false);
return;
}
// This can happen if picture was taken with a gesture.
if (mCaptureTime == 0) mCaptureTime = callbackTime - 300;
if (mCaptureNativeSize == null) mCaptureNativeSize = camera.getPictureSize();
PicturePreviewActivity.setImage(jpeg);
Intent intent = new Intent(CameraActivity.this, PicturePreviewActivity.class);
intent.putExtra("delay", callbackTime - mCaptureTime);
intent.putExtra("nativeWidth", mCaptureNativeSize.getWidth());
intent.putExtra("nativeHeight", mCaptureNativeSize.getHeight());
startActivity(intent);
mCaptureTime = 0;
mCaptureNativeSize = null;
}
private void onVideo(File video) {
mCapturingVideo = false;
Intent intent = new Intent(CameraActivity.this, VideoPreviewActivity.class);
intent.putExtra("video", Uri.fromFile(video));
startActivity(intent);
}
@Override
public void onClick(View view) {
switch (view.getId()) {
case R.id.edit: edit(); break;
case R.id.capturePhoto: capturePhoto(); break;
case R.id.captureVideo: captureVideo(); break;
case R.id.toggleCamera: toggleCamera(); break;
}
}
@Override
public void onBackPressed() {
BottomSheetBehavior b = BottomSheetBehavior.from(controlPanel);
if (b.getState() != BottomSheetBehavior.STATE_HIDDEN) {
b.setState(BottomSheetBehavior.STATE_HIDDEN);
return;
}
super.onBackPressed();
}
private void edit() {
BottomSheetBehavior b = BottomSheetBehavior.from(controlPanel);
b.setState(BottomSheetBehavior.STATE_COLLAPSED);
}
private void capturePhoto() {
if (mCapturingPicture) return;
mCapturingPicture = true;
mCaptureTime = System.currentTimeMillis();
mCaptureNativeSize = camera.getPictureSize();
message("Capturing picture...", false);
camera.capturePicture();
}
private void captureVideo() {
if (camera.getSessionType() != SessionType.VIDEO) {
message("Can't record video while session type is 'picture'.", false);
return;
}
if (mCapturingPicture || mCapturingVideo) return;
mCapturingVideo = true;
message("Recording for 8 seconds...", true);
camera.startCapturingVideo(null, 8000);
}
private void toggleCamera() {
if (mCapturingPicture) return;
switch (camera.toggleFacing()) {
case BACK:
message("Switched to back camera!", false);
break;
case FRONT:
message("Switched to front camera!", false);
break;
}
}
@Override
public boolean onValueChanged(Control control, Object value, String name) {
if (!camera.isHardwareAccelerated() && (control == Control.WIDTH || control == Control.HEIGHT)) {
if ((Integer) value > 0) {
message("This device does not support hardware acceleration. " +
"In this case you can not change width or height. " +
"The view will act as WRAP_CONTENT by default.", true);
return false;
}
}
control.applyValue(camera, value);
BottomSheetBehavior b = BottomSheetBehavior.from(controlPanel);
b.setState(BottomSheetBehavior.STATE_HIDDEN);
message("Changed " + control.getName() + " to " + name, false);
return true;
}
//region Boilerplate
@Override
protected void onResume() {
super.onResume();
camera.start();
}
@Override
protected void onPause() {
super.onPause();
camera.stop();
}
@Override
protected void onDestroy() {
super.onDestroy();
camera.destroy();
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
boolean valid = true;
for (int grantResult : grantResults) {
valid = valid && grantResult == PackageManager.PERMISSION_GRANTED;
}
if (valid && !camera.isStarted()) {
camera.start();
}
}
//endregion
}
我还添加了读写外部存储的权限。 但是我想知道图片保存后的大小。
添加代码以保存图像 -
public void KickOut(String filename,Bitmap bitmap){
ActivityCompat.requestPermissions(PicturePreviewActivity.this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},1);
OutputStream outputStream;
File filepath=Environment.getExternalStorageDirectory();
// File dir=new File(filepath+"/Olaa/");
File dir=new File("/Environment.getExternalStoragePublicDirectory/Imgs/");
dir.mkdirs();
File file=new File(dir,"filename.png");
Toast.makeText(PicturePreviewActivity.this, file + " -> saved" , Toast.LENGTH_SHORT).show();
try{
outputStream=new FileOutputStream(file);
bitmap.compress(Bitmap.CompressFormat.PNG,100,outputStream);
outputStream.flush();outputStream.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
// Toast.makeText(PicturePreviewActivity.this, filepath + " -> path" , Toast.LENGTH_SHORT).show();
}
答案 0 :(得分：1)
您可以检查捕获图像的大小，也可以将文件保存在自定义文件夹中。
你可以在onActivityResult（）中获得结果并从包中获取图像并将其转换为字节，而lengthbmp_KB将以kb为单位给出大小。
if (resultCode == RESULT_OK) {
//Image capture
if (requestCode == 1) {
Bitmap thumbnail = (Bitmap) data.getExtras().get("data");
ByteArrayOutputStream bytes = new ByteArrayOutputStream();
thumbnail.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
byte[] imageInByte = bytes.toByteArray();
long lengthbmp = imageInByte.length;
// save on custom folder
File destination1 = createDirectoryAndSaveFile(thumbnail, System.currentTimeMillis() + ".jpg");
/* File destination = new File(Environment.getExternalStorageDirectory(),
System.currentTimeMillis() + ".jpg");*/
picturePath = "" + destination1;
// show image on gallery
scanGallery(getActivity(), picturePath);
long lengthbmp_KB = lengthbmp / 1024;
long length_MB = lengthbmp_KB / 1024;
}
您可以将文件保存在自己的文件夹中
private File createDirectoryAndSaveFile(Bitmap imageToSave, String fileName) {
File direct = new File(Environment.getExternalStorageDirectory() + "/My Images");
if (!direct.exists()) {
File wallpaperDirectory = new File("/sdcard/MYfolder Images/");
wallpaperDirectory.mkdirs();
}
File file = new File(new File("/sdcard/Myfolder Images/"), fileName);
/* if (file.exists()) {
file.delete();
}*/
try {
FileOutputStream out = new FileOutputStream(file);
imageToSave.compress(Bitmap.CompressFormat.JPEG, 100, out);
out.flush();
out.close();
} catch (Exception e) {
e.printStackTrace();
}
return file;
}
您可以使用此MediaScannerConnection
在图库中查看图像
private void scanGallery(Context cntx, String path) {
try {
MediaScannerConnection.scanFile(cntx, new String[]{path}, null, new MediaScannerConnection.OnScanCompletedListener() {
public void onScanCompleted(String path, Uri uri) {
}
});
} catch (Exception e) {
e.printStackTrace();
}
}
并在onActivityResult（）
中使用此方法答案 1 :(得分：0)
要检查手机记忆库中保存的图像大小，可以使用Bitmapfactory.option
**BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(filename, options);
int imageHeight = options.outHeight;
int imageWidth = options.outWidth;**
答案 2 :(得分：0)
如果您已在清单中获得权限，则可以使用此文件保存文件。
static final int REQUEST_TAKE_PHOTO = 1;
private void dispatchTakePictureIntent() {
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
// Ensure that there's a camera activity to handle the intent
if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
// Create the File where the photo should go
File photoFile = null;
try {
photoFile = createImageFile();
} catch (IOException ex) {
// Error occurred while creating the File
...
}
// Continue only if the File was successfully created
if (photoFile != null) {
Uri photoURI = FileProvider.getUriForFile(this,
"com.example.android.fileprovider",
photoFile);
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);
}
}
}