Action Image Capture 在查看时导致图像模糊

Question

当我在 Android 应用程序中拍照时，显示模糊/缩小的图像，我确实意识到这将来自位图 .....data.getExtras().get ("data") 代码但是我更改的其他任何内容都不起作用，显示的图像仍然模糊。

如何让它显示完整的分辨率图片？

相机意图代码

private void cameraIntent()
{
    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    startActivityForResult(intent, REQUEST_IMAGE_CAPTURE);
}

关于活动代码

protected void onActivityResult(int requestCode, int resultCode, Intent data) {

    if (resultCode == Activity.RESULT_OK) {
        if (requestCode == REQUEST_CODE_GALLERY)
            onSelectFromGalleryResult(data);
        else if (requestCode == REQUEST_IMAGE_CAPTURE)
            onCaptureImageResult(data);
    }
    super.onActivityResult(requestCode, resultCode, data);
}

最后是 oncaptureImageResult - 我相信我会因为模糊图像而出错

private void onCaptureImageResult(Intent data) {
    Bitmap thumbnail = (Bitmap) data.getExtras().get("data");
    ByteArrayOutputStream bytes = new ByteArrayOutputStream();
    thumbnail.compress(Bitmap.CompressFormat.JPEG, 90, bytes);

    File destination = new File(Environment.getExternalStorageDirectory(),
            System.currentTimeMillis() + ".jpg");

    FileOutputStream fo;
    try {
        destination.createNewFile();
        fo = new FileOutputStream(destination);
        fo.write(bytes.toByteArray());
        fo.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

    imageView.setImageBitmap(thumbnail);
}

Answer 1

试试 WeakReference，这将返回清晰的图像而不会降低质量

  WeakReference<Bitmap> result1 = new WeakReference<Bitmap>(Bitmap.createScaledBitmap(src,
            src.getWidth(), src.getHeight(), false).copy(
            Bitmap.Config.RGB_565, true));
Bitmap bm=result1.get(); //Set this bitmap to any imageview that you want to display your image.

将上述代码放在 onCaptureImageResult() 方法中，例如

private void onCaptureImageResult(Intent data) {
Bitmap thumbnail = (Bitmap) data.getExtras().get("data");
WeakReference<Bitmap> result1 = new WeakReference<Bitmap>(Bitmap.createScaledBitmap(thumbnail,
        thumbnail.getWidth(), thumbnail.getHeight(), false).copy(
        Bitmap.Config.RGB_565, true));
   Bitmap bm=result1.get();
   imageView.setImageBitmap(bm);}

Answer 2

试试这个，这将返回准确的图像而不会降低质量..

Uri u;

 private void cameraIntent() {
        long time = System.currentTimeMillis();
        String stvalue = Long.toString(time);
        Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        File dir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM);
        File output = new File(dir, stvalue);
        u = Uri.fromFile(output);
        intent.putExtra(MediaStore.EXTRA_OUTPUT, u);
        startActivityForResult(intent, REQUEST_CAMERA);
}

 @Override
public void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    outState.putParcelable("file_uri", u);
}

@Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
    super.onRestoreInstanceState(savedInstanceState);
    u = savedInstanceState.getParcelable("file_uri");
}

然后在onActivityResult中

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if (resultCode == RESULT_OK) {          
        camerastore(u);
        break;
    } else {
        utils.Toast("Error in importing file");
    }
}


void camerastore(Uri u) {
    Bitmap bitmap = null;
    File pictureFile = new File("yourpath/image.jpg");

    try {
        bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), u);
        FileOutputStream fos = new FileOutputStream(pictureFile);
        bitmap.compress(Bitmap.CompressFormat.PNG, 100, fos)
        fos.close();
    } catch (Exception e) {
        e.printStackTrace();
    }

}

Answer 3

改变这一行。

 thumbnail.compress(Bitmap.CompressFormat.JPEG, 90, bytes);

到

 thumbnail.compress(Bitmap.CompressFormat.JPEG, 100, bytes);

Answer 4

您使用JPEG 压缩格式压缩图像过多，通过在质量中指定90 会额外损失10% 的图像质量。基本上你会进行有损压缩。要进行无损压缩，您应该选择 100% 质量的 PNG 压缩格式。你可以这样做：

Bitmap bitmap = (Bitmap) data.getExtras().get("data");
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);

还有一条建议。在File Provider 的帮助下，在cameraIntent() 方法本身中创建图像文件，在onActivity 中仅显示来自文件的图像。它提供了卓越的品质。