Question

=>我们已经创建了一个图像编辑器。但是，我保存了编辑后的图像，然后图像分辨率下降了。

=>我的保存方法是：bitMap.compress(Bitmap.CompressFormat.PNG, 100, stream);

=>在android中以原始分辨率保存图像的任何想法。

=>任何库或其他方式

<com.example.shreejiweb.canvas.PaintView
           android:id="@+id/paint_view"
           android:background="@android:color/black"
           android:layout_width="wrap_content"
           android:layout_height="wrap_content" />

MainActivity

package com.example.shreejiweb.canvas;

import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

public class MainActivity extends AppCompatActivity {

    PaintView mPaintView;
    Button mBtnPick,btn_save;
    int mWidth;
    int mHeight;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mWidth = mHeight = 0;

        // Getting reference to PaintView
        mPaintView = (PaintView) findViewById(R.id.paint_view);

        // Getting reference to Button "Pick an Image"
        mBtnPick = (Button) findViewById(R.id.btn_pick);
        btn_save = findViewById(R.id.btn_save);
        // Setting OnClickListener for the button
        mBtnPick.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                Intent i = new Intent();
                i.setType("image/*");
                i.setAction(Intent.ACTION_GET_CONTENT);

                Intent customChooserIntent = Intent.createChooser(i, "Pick an image");
                startActivityForResult(customChooserIntent, 10);
            }
        });

        btn_save.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                View content = mPaintView;
                content.setDrawingCacheEnabled(true);
                content.setDrawingCacheQuality(View.DRAWING_CACHE_QUALITY_HIGH);
                Bitmap bitmap = content.getDrawingCache();
                String path = Environment.getExternalStorageDirectory().getAbsolutePath();
                File file = new File(path+"/image.png");
                FileOutputStream ostream;
                try {
                    file.createNewFile();
                    ostream = new FileOutputStream(file);
                    bitmap.compress(Bitmap.CompressFormat.PNG, 100, ostream);
                    ostream.flush();
                    ostream.close();
                    Toast.makeText(getApplicationContext(), "image saved", Toast.LENGTH_LONG).show();
                } catch (Exception e) {
                    e.printStackTrace();
                    Toast.makeText(getApplicationContext(), "error", Toast.LENGTH_LONG).show();
                }
            }
        });

        if (savedInstanceState != null) {
            mWidth = savedInstanceState.getInt("width");
            mHeight = savedInstanceState.getInt("height");
            Bitmap bitmap = savedInstanceState.getParcelable("bitmap");
            if (bitmap != null) {

                mPaintView.addBitmap(bitmap);
            }
        }

    }

    // Courtesy : developer.android.com/training/displaying-bitmaps/load-bitmap.html
    public static int calculateInSampleSize(
            BitmapFactory.Options options, int reqWidth, int reqHeight) {
        // Raw height and width of image
        final int height = options.outHeight;
        final int width = options.outWidth;
        int inSampleSize = 1;

        if (height > reqHeight || width > reqWidth) {

            // Calculate ratios of height and width to requested height and width
            final int heightRatio = Math.round((float) height / (float) reqHeight);
            final int widthRatio = Math.round((float) width / (float) reqWidth);

            // Choose the smallest ratio as inSampleSize value, this will guarantee
            // a final image with both dimensions larger than or equal to the
            // requested height and width.
            inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
        }

        return inSampleSize;
    }


    private Bitmap getBitmapFromUri(Uri data) {
        Bitmap bitmap = null;

        // Starting fetch image from file
        InputStream is = null;
        try {

            is = getContentResolver().openInputStream(data);

            // First decode with inJustDecodeBounds=true to check dimensions
            final BitmapFactory.Options options = new BitmapFactory.Options();
            options.inJustDecodeBounds = true;

            // BitmapFactory.decodeFile(path, options);
            BitmapFactory.decodeStream(is, null, options);

            // Calculate inSampleSize
//            options.inSampleSize = calculateInSampleSize(options, mWidth, mHeight);

            // Decode bitmap with inSampleSize set
            options.inJustDecodeBounds = false;

            is = getContentResolver().openInputStream(data);

            bitmap = BitmapFactory.decodeStream(is, null, options);


            if (bitmap == null) {
                Toast.makeText(getBaseContext(), "Image is not Loaded", Toast.LENGTH_SHORT).show();
                return null;
            }

            assert is != null;
            is.close();
        } catch (IOException | NullPointerException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return bitmap;
    }


    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
        // TODO Auto-generated method stub
        super.onActivityResult(requestCode, resultCode, intent);
        if (requestCode == 10 && resultCode == RESULT_OK && null != intent) {
            Uri data = intent.getData();
            Uri imageUri = intent.getData();
            Bitmap bitmap = null;
            try {
                bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), imageUri);
            } catch (IOException e) {
                e.printStackTrace();
            }

//            Bitmap bitmap = getBitmapFromUri(data);
            if (bitmap != null) {
                mPaintView.addBitmap(bitmap);
            }
        }
    }


    @Override
    public void onWindowFocusChanged(boolean hasFocus) {
        // TODO Auto-generated method stub
        super.onWindowFocusChanged(hasFocus);
        mWidth = mPaintView.getWidth();
        mHeight = mPaintView.getHeight();
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {

        outState.putInt("width", mWidth);
        outState.putInt("height", mHeight);
        if (mPaintView.getBitmap() != null) {
            outState.putParcelable("bitmap", mPaintView.getBitmap());
        }

        super.onSaveInstanceState(outState);

    }

    @Override
    protected void onResume() {

        mPaintView.pause(false);

        // Resume repainting
        mPaintView.invalidate();

        super.onResume();
    }

    @Override
    protected void onPause() {

        // Pause repainting
        mPaintView.pause(true);

        super.onPause();

    }
}

Answer 1

“原始分辨率”是位图，因此您只需要获取位图像素，然后将其写入到文件中即可添加文件头的文件：Android : save a Bitmap to bmp file format

如何以原始分辨率保存编辑的图像？

1 个答案: