Question

我正在使用相机拍摄照片：

mCamera.takePicture(null, null,
                            new PhotoHandler(getApplicationContext()));

但是我拍摄的照片是风景画，我想要它是肖像画，我尝试将文件转换为位图，旋转它然后再次保存，这里是我的onPictureTaken()函数和rotate()函数PhotoHandler.class：

@Override
public void onPictureTaken(byte[] data, Camera camera) {
    File pictureFileDir = getDir();
    if (!pictureFileDir.exists() && !pictureFileDir.mkdirs()) {
        Log.d("Error", "Can't create directory to save image.");
        Toast.makeText(context, "Can't create directory to save image.",
                Toast.LENGTH_LONG).show();
        return;
    }
    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyymmddhhmmss");
    String date = dateFormat.format(new Date());
    String photoFile = "Picture_" + date + ".jpg";
    String filename = pictureFileDir.getPath() + File.separator + photoFile;
    pictureFile = new File(filename);
    st1 = pictureFile.getAbsolutePath();
    try {
        FileOutputStream fos = new FileOutputStream(pictureFile);
        fos.write(data);
        fos.close();
        Toast.makeText(context, "New Image saved:" + photoFile,
                Toast.LENGTH_LONG).show();
    } catch (Exception error) {
        Log.d("Error", "File" + filename + "not saved: "
                + error.getMessage());
        Toast.makeText(context, "Image could not be saved.",
                Toast.LENGTH_LONG).show();
    }
    Bitmap b = rotate(BitmapFactory.decodeFile(pictureFile.getAbsolutePath()),270);
    FileOutputStream out = null;
    try {
        out = new FileOutputStream(pictureFile);
        b.compress(Bitmap.CompressFormat.PNG, 100, out);
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            if (out != null) {
                out.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    CameraPreview.safeToTakePicture = true;
    galleryAddPic();
}

public static Bitmap rotate(Bitmap bitmap, int degree) {
    int w = bitmap.getWidth();
    int h = bitmap.getHeight();
    Matrix mtx = new Matrix();
    mtx.setRotate(degree);
    return Bitmap.createBitmap(bitmap, 0, 0, w, h, mtx, true);
}

无论如何，它需要太长时间，我尝试使用mCamera.setDisplayOrientation(90);但它只更改了相机的预览，拍摄的照片仍然相同，我也尝试获取相机的参数并像这里一样更改：

Camera.Parameters parameters = mCamera.getParameters();
parameters.set("orientation", "portrait");
mCamera.setParameters(parameters);

如果没有成功，我们将不胜感激。

编辑： 新代码：

@Override
public void onPictureTaken(byte[] data, Camera camera) {
    File pictureFileDir = getDir();
    if (!pictureFileDir.exists() && !pictureFileDir.mkdirs()) {
        Log.d("Error", "Can't create directory to save image.");
        Toast.makeText(context, "Can't create directory to save image.",
                Toast.LENGTH_LONG).show();
        return;
    }
    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyymmddhhmmss");
    String date = dateFormat.format(new Date());
    String photoFile = "Picture_" + date + ".jpg";
    String filename = pictureFileDir.getPath() + File.separator + photoFile;
    pictureFile = new File(filename);
    st1 = pictureFile.getAbsolutePath();
    Bitmap b = rotate(BitmapFactory.decodeByteArray(data,0,data.length),270);
    FileOutputStream out = null;
    try {
        out = new FileOutputStream(pictureFile);
        b.compress(Bitmap.CompressFormat.PNG, 100, out);
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            if (out != null) {
                out.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    CameraPreview.safeToTakePicture = true;
    galleryAddPic();
}

Answer 1

无论如何，这需要太长时间

您当前的算法如下所示：

从内存中的照片开始
将照片保存到磁盘，这很慢
将照片从磁盘读回内存，这很慢
旋转重新加载的照片

更有效的方法是：

从内存中的照片开始
旋转照片

BitmapFactory decodeByteArray()有Bitmap返回以供轮换使用。

takePicture（）横向模式旋转android

1 个答案: