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如何在上传到服务器之前在android中调整/压缩相机图像或图库图像?

[英]How to resize/compress a camera image or gallery image in android before upload to server?

I have to upload image which may be choose from gallery or take by camera. 我必须上传图片,可以从图库中选择或通过相机拍摄。 I have done this successfully. 我成功完成了这个。 But problem is , some time image size is 1MB. 但问题是,有些时候图像大小是1MB。 So it takes more time to upload to server. 因此上传到服务器需要更多时间。 I need to resize this image before upload. 我需要在上传之前调整此图片的大小。 How to do this? 这该怎么做?

 public void onActivityResult(int requestCode, int resultCode, Intent data)
{
    AlertDialog alertDialog1;

    if( requestCode == REQUEST_IMAGE && resultCode == Activity.RESULT_OK ){
        try {
            FileInputStream in = new FileInputStream(destination);
            BitmapFactory.Options options = new BitmapFactory.Options();
            options.inSampleSize = 10;
            imagePath = destination.getAbsolutePath();
            Bitmap bmp = BitmapFactory.decodeStream(in, null, options);
            //img = (ImageView) findViewById(R.id.imageView1);
            int nh = (int) ( bmp.getHeight() * (512.0 / bmp.getWidth()) );
            Bitmap scaled = Bitmap.createScaledBitmap(bmp, 512, nh, true);
            img.setImageBitmap(scaled);
        } catch (Exception e) {
            // AlertDialog alertDialog1;
            alertDialog1 = new AlertDialog.Builder(getActivity()).create();
            alertDialog1.setTitle("Message");
            alertDialog1.setMessage("bala \t "+e.toString());
            alertDialog1.show();
        }

    }else if (requestCode == 1) {
        try {
            Uri selectedImageUri = data.getData();
            imagePath =  getPath(selectedImageUri);
            destination = new File(imagePath);
            FileInputStream in = new FileInputStream(destination);
            BitmapFactory.Options options = new BitmapFactory.Options();
            options.inSampleSize = 10;
            imagePath = destination.getAbsolutePath();
            Bitmap bmp = BitmapFactory.decodeStream(in, null, options);
            //int nh = (int) ( bmp.getHeight() * (512.0 / bmp.getWidth()) );
           // Bitmap scaled = Bitmap.createScaledBitmap(bmp, 512, nh, true);
            img.setImageBitmap(bmp);

            //img.setImageBitmap(bmp);
        } catch (Exception e) {
            // AlertDialog alertDialog1;
            alertDialog1 = new AlertDialog.Builder(getActivity()).create();
            alertDialog1.setTitle("Message");
            alertDialog1.setMessage("sang\t"+e.toString());
            alertDialog1.show();
        }
    }
    else{

    }
}

Now, how to resize the image? 现在,如何调整图像大小?

  1. To resize image you can use the following function 要调整图像大小,您可以使用以下功能

    Bitmap yourBitmap; Bitmap resized = Bitmap.createScaledBitmap(yourBitmap, newWidth, newHeight, true);

  2. To compress the image 压缩图像

    Bitmap bmp = BitmapFactory.decodeFile(miFoto) ByteArrayOutputStream bos = new ByteArrayOutputStream(); bmp.compress(CompressFormat.JPEG, 70, bos); InputStream in = new ByteArrayInputStream(bos.toByteArray()); ContentBody foto = new InputStreamBody(in, "image/jpeg", "filename");

压缩位图就好

bmp = Bitmap.createScaledBitmap(bmp, 160, 160, true);

can use: 可以使用:

Bitmap bitmap = BitmapFactory.decodeFile(fileUri.getPath());
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 50, stream); //compress to 50% of original image quality
byte[] byte_arr = stream.toByteArray();

You can checkout this code it works same as you wanted WhatsApp Like Image Compression . 您可以签出此代码,它的工作方式与您想要的WhatsApp图像压缩相同 This code has been modified according to my usage. 此代码已根据我的用法进行了修改。 Using this code will provide you : 使用此代码将为您提供:

  • Low Size Images around 100kb without playing with image quality. 低尺寸图像约100kb,无需播放图像质量。
  • High pixel images will be scaled down to maxWidth and maxHeight without loosing its original quality. 高像素图像将缩小到maxWidthmaxHeight,而不会失去其原始质量。

Original Article : Loading images Super-Fast like WhatsApp 原始文章: 像WhatsApp一样加载超快速图像

Demo : 演示:

Original Image : Size - 3.84Mb Dimensions - 3120*4160 原始图像 :尺寸 - 3.84Mb尺寸 - 3120 * 4160

Compressed Image : Size - 157Kb Dimensions - 960*1280 压缩图像 :尺寸 - 157Kb尺寸 - 960 * 1280

you need to compress the image because Re-scaling bitmap reduce the quality of image. 您需要压缩图像,因为重新缩放位图会降低图像质量。 you can try this function for compress your image. 您可以尝试使用此功能来压缩图像。 just pass this funtion from where you upload your image in your activity. 只需通过您在活动中上传图片的功能。

/ Funtion for compress image
    public String compressImage(String imageUri) {

        String filePath = getRealPathFromURI(imageUri);
        Bitmap scaledBitmap = null;

        BitmapFactory.Options options = new BitmapFactory.Options();

//      by setting this field as true, the actual bitmap pixels are not loaded in the memory. Just the bounds are loaded. If
//      you try the use the bitmap here, you will get null.
        options.inJustDecodeBounds = true;
        Bitmap bmp = BitmapFactory.decodeFile(filePath, options);

        int actualHeight = options.outHeight;
        int actualWidth = options.outWidth;

//      max Height and width values of the compressed image is taken as 816x612

        float maxHeight = 816.0f;
        float maxWidth = 612.0f;
        float imgRatio = actualWidth / actualHeight;
        float 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 = (int) (imgRatio * actualWidth);               actualHeight = (int) maxHeight;             } else if (imgRatio > maxRatio) {
                imgRatio = maxWidth / actualWidth;
                actualHeight = (int) (imgRatio * actualHeight);
                actualWidth = (int) maxWidth;
            } else {
                actualHeight = (int) maxHeight;
                actualWidth = (int) maxWidth;

            }
        }

//      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 = new byte[16 * 1024];

        try {
//          load the bitmap from its path
            bmp = BitmapFactory.decodeFile(filePath, options);
        } catch (OutOfMemoryError exception) {
            exception.printStackTrace();

        }
        try {
            scaledBitmap = Bitmap.createBitmap(actualWidth, actualHeight,Bitmap.Config.ARGB_8888);
        } catch (OutOfMemoryError exception) {
            exception.printStackTrace();
        }

        float ratioX = actualWidth / (float) options.outWidth;
        float ratioY = actualHeight / (float) options.outHeight;
        float middleX = actualWidth / 2.0f;
        float middleY = actualHeight / 2.0f;

        Matrix scaleMatrix = new Matrix();
        scaleMatrix.setScale(ratioX, ratioY, middleX, middleY);

        Canvas canvas = new Canvas(scaledBitmap);
        canvas.setMatrix(scaleMatrix);
        canvas.drawBitmap(bmp, middleX - bmp.getWidth() / 2, middleY - bmp.getHeight() / 2, new Paint(Paint.FILTER_BITMAP_FLAG));

//      check the rotation of the image and display it properly
        ExifInterface exif;
        try {
            exif = new ExifInterface(filePath);

            int orientation = exif.getAttributeInt(
                    ExifInterface.TAG_ORIENTATION, 0);
            Log.d("EXIF", "Exif: " + orientation);
            Matrix matrix = new Matrix();
            if (orientation == 6) {
                matrix.postRotate(90);
                Log.d("EXIF", "Exif: " + orientation);
            } else if (orientation == 3) {
                matrix.postRotate(180);
                Log.d("EXIF", "Exif: " + orientation);
            } else if (orientation == 8) {
                matrix.postRotate(270);
                Log.d("EXIF", "Exif: " + orientation);
            }
            scaledBitmap = Bitmap.createBitmap(scaledBitmap, 0, 0, scaledBitmap.getWidth(), scaledBitmap.getHeight(), matrix, true);
        } catch (IOException e) {
            e.printStackTrace();
        }

        FileOutputStream out = null;
        String filename = getFilename();
        try {
            out = new FileOutputStream(filename);

//          write the compressed bitmap at the destination specified by filename.
            scaledBitmap.compress(Bitmap.CompressFormat.JPEG, 80, out);

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }

        return filename;

    }


    public String getFilename() {
        File file = new File(Environment.getExternalStorageDirectory().getPath(), "MyFolder/Images");
        if (!file.exists()) {
            file.mkdirs();
        }
        String uriSting = (file.getAbsolutePath() + "/" + System.currentTimeMillis() + ".jpg");
        return uriSting;

    }

    private String getRealPathFromURI(String contentURI) {
        Uri contentUri = Uri.parse(contentURI);
        Cursor cursor = getContentResolver().query(contentUri, null, null, null, null);
        if (cursor == null) {
            return contentUri.getPath();
        } else {
            cursor.moveToFirst();
            int index = cursor.getColumnIndex(MediaStore.Images.ImageColumns.DATA);
            return cursor.getString(index);
        }
    }

    public int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) {
        final int height = options.outHeight;
        final int width = options.outWidth;
        int inSampleSize = 1;

        if (height > reqHeight || width > reqWidth) {
            final int heightRatio = Math.round((float) height/ (float) reqHeight);
            final int widthRatio = Math.round((float) width / (float) reqWidth);
            inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;      }       final float totalPixels = width * height;       final float totalReqPixelsCap = reqWidth * reqHeight * 2;       while (totalPixels / (inSampleSize * inSampleSize) > totalReqPixelsCap) {
            inSampleSize++;
        }

        return inSampleSize;
    }

    //
    private void previewMedia(boolean isImage) {


        // Checking whether captured media is image or video
        if (isImage) {
            photo.setVisibility(View.VISIBLE);
            // vidPreview.setVisibility(View.GONE);
            // bimatp factory
            BitmapFactory.Options options = new BitmapFactory.Options();


            // down sizing image as it throws OutOfMemory Exception for larger
            // images
            options.inSampleSize = 2;


            final Bitmap bitmap = BitmapFactory.decodeFile(filePath, options);
            options.inJustDecodeBounds = true;


            photo.setImageBitmap(bitmap);

        }


    }

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