旋转后如何保存图像位图? [英] How to save image bitmap after rotation?

问题描述

我开发了将图像保存到sd卡的应用程序，并且所有图片都在上方，我想旋转它们并将它们保存在我选择的旋转位置. 我知道如何旋转我的代码，但图像不会永久保存. 这是我的代码: //旋转图片

I develop app that save images to sd Card and all the pictures are upside i want to rotate them and save them in the rotate position i choose . i know how to rotate on my code but the image is not saved permanently. here is my code : //Rotate the picture

public static Bitmap rotate(Bitmap source, float angle) {
    Matrix matrix = new Matrix();
    matrix.postRotate(angle);

    return Bitmap.createBitmap(source, 0, 0, source.getWidth(),source.getHeight(), matrix, false);  
}

//调整图片大小

public void resizeImage(String path , int Wdist,int Hdist){
    try
    {
        int inWidth = 0;
        int inHeight = 0;


        InputStream in = new FileInputStream(path);

        // decode image size (decode metadata only, not the whole image)
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true; 
        BitmapFactory.decodeStream(in, null, options);
        in.close();
        in = null;

        // save width and height
        inWidth = options.outWidth;
        inHeight = options.outHeight;

        // decode full image pre-resized
        in = new FileInputStream(path);
        options = new BitmapFactory.Options();
        // calc rought re-size (this is no exact resize)
        options.inSampleSize = Math.max(inWidth/Wdist, inHeight/Hdist);
        // decode full image
        Bitmap roughBitmap = BitmapFactory.decodeStream(in, null, options);

        // calc exact destination size
        Matrix m = new Matrix();

        RectF inRect = new RectF(0, 0, roughBitmap.getWidth(), roughBitmap.getHeight());
        RectF outRect = new RectF(0, 0, Wdist, Hdist);
        m.setRectToRect(inRect, outRect, Matrix.ScaleToFit.CENTER);
        float[] values = new float[9];
        m.getValues(values);

        // resize bitmap
        Bitmap resizedBitmap = Bitmap.createScaledBitmap(roughBitmap, (int) (roughBitmap.getWidth() * values[0]), (int) (roughBitmap.getHeight() * values[4]), true);

        // save image
        try
        {
            FileOutputStream out = new FileOutputStream(path);
            resizedBitmap.compress(Bitmap.CompressFormat.JPEG, 80, out);
        }
        catch (Exception e)
        {
            Log.e("Image", e.getMessage(), e);
        }
    }
    catch (IOException e)
    {
        Log.e("Image", e.getMessage(), e);
    }
}

感谢帮手:)

推荐答案

尝试以下代码.

String root = Environment.getExternalStorageDirectory().toString();
File myDir = new File(root + "/saved_images");    
myDir.mkdirs();
Random generator = new Random();
int n = 10000;
n = generator.nextInt(n);
String fname = "Image-"+ n +".jpg";
File file = new File (myDir, fname);
if (file.exists ()) file.delete (); 
try {
       finalBitmap = rotate(bmp,50);
       FileOutputStream out = new FileOutputStream(file);
       finalBitmap.compress(Bitmap.CompressFormat.JPEG, 90, out);
       out.flush();
       out.close();

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

别忘了从Manifest

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

这篇关于旋转后如何保存图像位图?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！