相关疑难解决方法(0)

我正在尝试将从相机中检索到的图像(大约5-8百万像素)缩小到一个较小的尺寸(最大为1024x768).我尝试了以下代码,但我一直得到一个OutOfMemoryError.

Bitmap image = BitmapFactory.decodeStream(this.image, null, opt);
int imgWidth = image.getWidth();
int imgHeight = image.getHeight();

// Constrain to given size but keep aspect ratio
float scaleFactor = Math.min(((float) width) / imgWidth, ((float) height) / imgHeight);

Matrix scale = new Matrix();
scale.postScale(scaleFactor, scaleFactor);
final Bitmap scaledImage = Bitmap.createBitmap(image, 0, 0, imgWidth, imgHeight, scale, false);

image.recycle();

看起来OOM发生在createBitmap.是否有更高效的内存方式？也许某些东西不需要我将整个原件加载到内存中？

我想使用drawBitmap()方法显示图像.但在我想根据屏幕尺寸调整大小之前.我的结果图像质量有问题.您可以在下面看到屏幕截图和测试代码.如何在运行时以高质量调整图像大小？

谢谢你的解决方案.

原始图片: alt text http://dl.dropbox.com/u/709109/gradient.png

设备上的结果屏幕截图: alt text http://dl.dropbox.com/u/709109/device.png

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.os.Bundle;
import android.view.View;
import android.widget.LinearLayout;

import java.io.IOException;
import java.io.InputStream;

public class MyActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        LinearLayout container = (LinearLayout) findViewById(R.id.container);
        container.addView(new View(this) {
            @Override
            protected void onDraw(Canvas canvas) {
                Bitmap unscaledBitmap;
                try {
                    InputStream in = getAssets().open("images/gradient.png");
                    unscaledBitmap = BitmapFactory.decodeStream(in);
                    in.close();
                    canvas.drawBitmap(unscaledBitmap, null, new Rect(0, 0, 320, 480), null);
                } catch …