我在下面有这个代码，我想在发送到Firebase之前降低源自相机或图库的图像质量。 正在发送图像的路径（Uri），如何在此处实现代码？
我该怎么办？ .................................................. .................................................. ....................................
private void showFileChooser() {
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Select Picture"), PICK_IMAGE_REQUEST);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if ((requestCode == PICK_IMAGE_REQUEST || requestCode == REQUEST_IMAGE_CAPTURE) && resultCode == RESULT_OK && data != null && data.getData() != null) {
filePath = data.getData();
if (requestCode == PICK_IMAGE_REQUEST) {
try {
Bitmap bitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), filePath);
imageView.setImageBitmap(bitmap);
} catch (IOException e) {
e.printStackTrace();
}
} else if (requestCode == REQUEST_IMAGE_CAPTURE) {
filePath = data.getData();
Uri selectedImageUri = data.getData();
imageView.setImageURI(selectedImageUri);
}
}
}
public String getFileExtension(Uri uri) {
ContentResolver cR = getContentResolver();
MimeTypeMap mime = MimeTypeMap.getSingleton();
return mime.getExtensionFromMimeType(cR.getType(uri));
}
private void uploadFile() {
//checking if file is available
if (filePath != null && (editTextName.getText().toString().length() > 0)
&& (editTextName1.getText().toString().length() > 0)
&& (editTextName2.getText().toString().length() > 0)
) {
//displaying progress dialog while image is uploading
final ProgressDialog progressDialog = new ProgressDialog(this);
progressDialog.setTitle("Uploading");
progressDialog.show();
//getting the storage reference
StorageReference sRef = storageReference.child(Constants.STORAGE_PATH_UPLOADS + System.currentTimeMillis() + "." + getFileExtension(filePath));
//adding the file to reference
sRef.putFile(filePath)
.addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
@Override
public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {
//dismissing the progress dialog
progressDialog.dismiss();
//displaying success toast
Toast.makeText(getApplicationContext(), "File Uploaded ", Toast.LENGTH_LONG).show();
Intent intent = new Intent(MainActivity.this, ShowMap.class);
startActivity(intent);
//creating the upload object to store uploaded image details
Upload upload = new Upload(editTextName.getText().toString().trim(), editTextName1.getText().toString().trim(), editTextName2.getText().toString().trim(), editTextLatitude.getText().toString().trim(), editTextLongitude.getText().toString().trim(), taskSnapshot.getDownloadUrl().toString());
//adding an upload to firebase database
String uploadId = mDatabase.push().getKey();
mDatabase.child(uploadId).setValue(upload);
}
})
.addOnFailureListener(new OnFailureListener() {
@Override
public void onFailure(@NonNull Exception exception) {
progressDialog.dismiss();
Toast.makeText(getApplicationContext(), exception.getMessage(), Toast.LENGTH_LONG).show();
}
})
.addOnProgressListener(new OnProgressListener<UploadTask.TaskSnapshot>() {
@Override
public void onProgress(UploadTask.TaskSnapshot taskSnapshot) {
//displaying the upload progress
double progress = (100.0 * taskSnapshot.getBytesTransferred()) / taskSnapshot.getTotalByteCount();
progressDialog.setMessage("Uploaded " + ((int) progress) + "%...");
}
});
}else{
Toast.makeText(this, "Error", Toast.LENGTH_LONG).show();
} //display an error if no file is selected
}
答案 0 :(得分：0)
Bitmap image2 = (Bitmap) data.getExtras().get("data");
img.setImageBitmap(image2);
String incident_ID = IncidentFormActivity.incident_id;
imagepath="/sdcard/RDMS/"+incident_ID+ x + ".PNG";
File file = new File(imagepath);
try {
double xFactor = 0;
double width = Double.valueOf(image2.getWidth());
Log.v("WIDTH", String.valueOf(width));
double height = Double.valueOf(image2.getHeight());
Log.v("height", String.valueOf(height));
if(width>height){
xFactor = 841/width;
}
else{
xFactor = 595/width;
}
Log.v("Nheight", String.valueOf(width*xFactor));
Log.v("Nweight", String.valueOf(height*xFactor));
int Nheight = (int) ((xFactor*height));
int NWidth =(int) (xFactor * width) ;
bm = Bitmap.createScaledBitmap( image2,NWidth, Nheight, true);
file.createNewFile();
FileOutputStream ostream = new FileOutputStream(file);
bm.compress(CompressFormat.PNG, 100, ostream);
ostream.close();
这是调整图片大小的代码..
答案 1 :(得分：0)
检查这个课程。这有助于压缩图像
class ImageFile(val uri: Uri, name: String) {
val filename: String
init {
val file = File(Environment.getExternalStorageDirectory().toString() + "/Documents")
if (!file.exists()) {
file.mkdirs()
}
val fileNoMedia = File(file.absolutePath + "/.nomedia")
if (!fileNoMedia.exists())
fileNoMedia.createNewFile()
if (name.toLowerCase().endsWith(".pdf")) {
filename = file.absolutePath + "/" + System.currentTimeMillis() + ".pdf"
} else {
filename = file.absolutePath + "/" + System.currentTimeMillis() + ".jpg"
}
}
@Throws(IOException::class)
fun copyFileStream(context: Context, uri: Uri): String {
if (filename.endsWith(".pdf") || filename.endsWith(".PDF")) {
var ins: InputStream? = null
var os: OutputStream? = null
try {
ins = context.getContentResolver().openInputStream(uri)
os = FileOutputStream(filename)
val buffer = ByteArray(1024)
var length: Int = ins.read(buffer)
while (length > 0) {
os.write(buffer, 0, length);
length = ins.read(buffer)
}
} catch (e: Exception) {
e.printStackTrace();
} finally {
ins?.close()
os?.close()
}
} else {
var ins: InputStream? = null
var os: OutputStream? = null
try {
ins = context.getContentResolver().openInputStream(uri)
var scaledBitmap: Bitmap? = null
val options = BitmapFactory.Options()
options.inJustDecodeBounds = true
var bmp = BitmapFactory.decodeStream(ins, null, options)
var actualHeight = options.outHeight
var actualWidth = options.outWidth
// max Height and width values of the compressed image is taken as 816x612
val maxHeight = 816.0f
val maxWidth = 612.0f
var imgRatio = (actualWidth / actualHeight).toFloat()
val maxRatio = maxWidth / maxHeight
// width and height values are set maintaining the aspect ratio of the image
if (actualHeight > maxHeight || actualWidth > maxWidth) {
if (imgRatio < maxRatio) {
imgRatio = maxHeight / actualHeight
actualWidth = (imgRatio * actualWidth).toInt()
actualHeight = maxHeight.toInt()
} else if (imgRatio > maxRatio) {
imgRatio = maxWidth / actualWidth
actualHeight = (imgRatio * actualHeight).toInt()
actualWidth = maxWidth.toInt()
} else {
actualHeight = maxHeight.toInt()
actualWidth = maxWidth.toInt()
}
}
// setting inSampleSize value allows to load a scaled down version of the original image
options.inSampleSize = calculateInSampleSize(options, actualWidth, actualHeight)
// inJustDecodeBounds set to false to load the actual bitmap
options.inJustDecodeBounds = false
// this options allow android to claim the bitmap memory if it runs low on memory
options.inPurgeable = true
options.inInputShareable = true
options.inTempStorage = ByteArray(16 * 1024)
try {
// load the bitmap from its path
ins.close()
ins = context.getContentResolver().openInputStream(uri)
bmp = BitmapFactory.decodeStream(ins, null, options)
} catch (exception: OutOfMemoryError) {
exception.printStackTrace()
}
try {
scaledBitmap = Bitmap.createBitmap(actualWidth, actualHeight, Bitmap.Config.ARGB_8888)
} catch (exception: OutOfMemoryError) {
exception.printStackTrace()
}
val ratioX = actualWidth / options.outWidth.toFloat()
val ratioY = actualHeight / options.outHeight.toFloat()
val middleX = actualWidth / 2.0f
val middleY = actualHeight / 2.0f
val scaleMatrix = Matrix()
scaleMatrix.setScale(ratioX, ratioY, middleX, middleY)
val canvas = Canvas(scaledBitmap!!)
canvas.matrix = scaleMatrix
canvas.drawBitmap(bmp, middleX - bmp.width / 2, middleY - bmp.height / 2, Paint(Paint.FILTER_BITMAP_FLAG))
os = FileOutputStream(filename)
scaledBitmap.compress(Bitmap.CompressFormat.JPEG, 80, os)
val buffer = ByteArray(1024)
var length: Int = ins.read(buffer)
while (length > 0) {
os.write(buffer, 0, length);
length = ins.read(buffer)
}
} catch (e: Exception) {
e.printStackTrace();
} finally {
ins?.close()
os?.close()
}
}
return filename
}
fun calculateInSampleSize(options: BitmapFactory.Options, reqWidth: Int, reqHeight: Int): Int {
val height = options.outHeight
val width = options.outWidth
var inSampleSize = 1
if (height > reqHeight || width > reqWidth) {
val heightRatio = Math.round(height.toFloat() / reqHeight.toFloat())
val widthRatio = Math.round(width.toFloat() / reqWidth.toFloat())
inSampleSize = if (heightRatio < widthRatio) heightRatio else widthRatio
}
val totalPixels = (width * height).toFloat()
val totalReqPixelsCap = (reqWidth * reqHeight * 2).toFloat()
while (totalPixels / (inSampleSize * inSampleSize) > totalReqPixelsCap) {
inSampleSize++
}
return inSampleSize
}
}
了解更多信息，请访问this link
答案 2 :(得分：0)
我能够解决！
调整图片大小
private String storeImage(Bitmap image) {
File pictureFile = getOutputMediaFile();
if (pictureFile == null) {
Log.d("log",
"Error creating media file, check storage permissions: ");// e.getMessage());
return null;
}
try {
FileOutputStream fos = new FileOutputStream(pictureFile);
image.compress(Bitmap.CompressFormat.JPEG, 30, fos);
fos.close();
} catch (FileNotFoundException e) {
Log.d("log", "File not found: " + e.getMessage());
} catch (IOException e) {
Log.d("log", "Error accessing file: " + e.getMessage());
}
return null;
}
/** Create a File for saving an image or video */
private File getOutputMediaFile(){
// To be safe, you should check that the SDCard is mounted
// using Environment.getExternalStorageState() before doing this.
File mediaStorageDir = new File(Environment.getExternalStorageDirectory()
+ "/Android/data/"
+ getApplicationContext().getPackageName()
+ "/Files");
// This location works best if you want the created images to be shared
// between applications and persist after your app has been uninstalled.
// Create the storage directory if it does not exist
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("ddMMyyyy_HHmm").format(new Date());
File mediaFile;
String mImageName="MI_"+ timeStamp +".jpg";
mediaFile = new File(mediaStorageDir.getPath() + File.separator + mImageName);
Log.v("log", "save: " + mediaStorageDir.getAbsoluteFile());
return mediaFile;
}
onActivityResult
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if ((requestCode == PICK_IMAGE_REQUEST || requestCode == REQUEST_IMAGE_CAPTURE) && resultCode == RESULT_OK && data != null && data.getData() != null) {
filePath = data.getData();
if (requestCode == PICK_IMAGE_REQUEST) {
try {
bitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), filePath);
storeImage(bitmap);
imageView.setImageBitmap(bitmap);
Log.v("log", "path = " + getOutputMediaFile().getAbsoluteFile());
imagemfinal = Uri.fromFile(getOutputMediaFile().getAbsoluteFile());
} catch (IOException e) {
e.printStackTrace();
}
} else if (requestCode == REQUEST_IMAGE_CAPTURE) {
filePath = data.getData();
Uri selectedImageUri = data.getData();
try {
Bitmap bitmap1 = MediaStore.Images.Media.getBitmap(this.getContentResolver(), selectedImageUri);
storeImage(bitmap1);
imagemfinal = Uri.fromFile(getOutputMediaFile().getAbsoluteFile());
imageView.setImageBitmap(bitmap1);
} catch (IOException e) {
e.printStackTrace();
}
}
}
}