Question

我可以在gridview中屏蔽图像，但问题是如何在屏蔽中剪切或裁剪图像的蒙版内容。帮助我一些想法和一些演示..

public void makeMaskImage(ImageView mImageView, Bitmap mBitmap,
        int MASK_IMAGEVIEW, int IMAGEVIEW_THUMB_BACKGROUND) {
    try {
        Bitmap mask = BitmapFactory.decodeResource(mContext.getResources(),MASK_IMAGEVIEW);
        Bitmap result = Bitmap.createBitmap(mask.getWidth(),
                mask.getHeight(), Config.ARGB_8888);
        Canvas mCanvas = new Canvas(result);
        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));

        if (mBitmap == null) {
            mBitmap = BitmapFactory.decodeResource(mContext.getResources(),
                    R.drawable.no_image_friend);
            mImageView.setImageBitmap(mBitmap);
            return;
        }

        mCanvas.drawBitmap(mBitmap, 0, 0, null);
        mCanvas.drawBitmap(mask, 0, 0, paint);
        paint.setXfermode(null);
        try {
            mImageView .setImageBitmap(Bitmap_process(getImageBuffer(result)));
        } catch (IOException e) {
            e.printStackTrace();
        }
        mImageView.setScaleType(ScaleType.CENTER);
        mImageView.setBackgroundResource(IMAGEVIEW_THUMB_BACKGROUND);
    } catch (OutOfMemoryError e) {
        e.printStackTrace();
    }
}

Answer 1

您好以下可能是一些帮助

需要合适的图片

final long startTime = SystemClock.uptimeMillis（）;

    // Part 1: Decode image
    Bitmap unscaledBitmap = ScalingUtilities.decodeResource(getResources(), mSourceId,
            mDstWidth, mDstHeight, ScalingLogic.FIT);

    // Part 2: Scale image
    Bitmap scaledBitmap = ScalingUtilities.createScaledBitmap(unscaledBitmap, mDstWidth,
            mDstHeight, ScalingLogic.FIT);
    unscaledBitmap.recycle();

    // Calculate memory usage and performance statistics
    final int memUsageKb = (unscaledBitmap.getRowBytes() * unscaledBitmap.getHeight()) / 1024;
    final long stopTime = SystemClock.uptimeMillis();

    // Publish results
    mResultView.setText("Time taken: " + (stopTime - startTime)
            + " ms. Memory used for scaling: " + memUsageKb + " kb.");
    mImageView.setImageBitmap(scaledBitmap);

接下来如何裁剪图像

 final long startTime = SystemClock.uptimeMillis();

            // Part 1: Decode image
            Bitmap unscaledBitmap = ScalingUtilities.decodeResource(getResources(), mSourceId,
                    mDstWidth, mDstHeight, ScalingLogic.CROP);

            // Part 2: Scale image
            Bitmap scaledBitmap = ScalingUtilities.createScaledBitmap(unscaledBitmap, mDstWidth,
                    mDstHeight, ScalingLogic.CROP);
            unscaledBitmap.recycle();

            // Calculate memory usage and performance statistics
            final int memUsageKb = (unscaledBitmap.getRowBytes() * unscaledBitmap.getHeight()) / 1024;
            final long stopTime = SystemClock.uptimeMillis();

            // Publish results
            mResultView.setText("Time taken: " + (stopTime - startTime)
                    + " ms. Memory used for scaling: " + memUsageKb + " kb.");
            mImageView.setImageBitmap(scaledBitmap);

解码资源功能

 public static Bitmap decodeResource(Resources res, int resId, int dstWidth, int dstHeight,
            ScalingLogic scalingLogic) {
        Options options = new Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeResource(res, resId, options);
        options.inJustDecodeBounds = false;
        options.inSampleSize = calculateSampleSize(options.outWidth, options.outHeight, dstWidth,
                dstHeight, scalingLogic);
        Bitmap unscaledBitmap = BitmapFactory.decodeResource(res, resId, options);

        return unscaledBitmap;
    }

calculateSampleSize函数

public static int calculateSampleSize(int srcWidth, int srcHeight, int dstWidth, int dstHeight,
            ScalingLogic scalingLogic) {
        if (scalingLogic == ScalingLogic.FIT) {
            final float srcAspect = (float)srcWidth / (float)srcHeight;
            final float dstAspect = (float)dstWidth / (float)dstHeight;

            if (srcAspect > dstAspect) {
                return srcWidth / dstWidth;
            } else {
                return srcHeight / dstHeight;
            }
        } else {
            final float srcAspect = (float)srcWidth / (float)srcHeight;
            final float dstAspect = (float)dstWidth / (float)dstHeight;

            if (srcAspect > dstAspect) {
                return srcHeight / dstHeight;
            } else {
                return srcWidth / dstWidth;
            }
        }
    }

createScaledBitmap函数

public static Bitmap createScaledBitmap(Bitmap unscaledBitmap, int dstWidth, int dstHeight,
            ScalingLogic scalingLogic) {
        Rect srcRect = calculateSrcRect(unscaledBitmap.getWidth(), unscaledBitmap.getHeight(),
                dstWidth, dstHeight, scalingLogic);
        Rect dstRect = calculateDstRect(unscaledBitmap.getWidth(), unscaledBitmap.getHeight(),
                dstWidth, dstHeight, scalingLogic);
        Bitmap scaledBitmap = Bitmap.createBitmap(dstRect.width(), dstRect.height(),
                Config.ARGB_8888);
        Canvas canvas = new Canvas(scaledBitmap);
        canvas.drawBitmap(unscaledBitmap, srcRect, dstRect, new Paint(Paint.FILTER_BITMAP_FLAG));

        return scaledBitmap;
    }

ScalingLogic功能

 public static enum ScalingLogic {
        CROP, FIT
    }

calculateDstRect函数

 public static Rect calculateDstRect(int srcWidth, int srcHeight, int dstWidth, int dstHeight,
            ScalingLogic scalingLogic) {
        if (scalingLogic == ScalingLogic.FIT) {
            final float srcAspect = (float)srcWidth / (float)srcHeight;
            final float dstAspect = (float)dstWidth / (float)dstHeight;

            if (srcAspect > dstAspect) {
                return new Rect(0, 0, dstWidth, (int)(dstWidth / srcAspect));
            } else {
                return new Rect(0, 0, (int)(dstHeight * srcAspect), dstHeight);
            }
        } else {
            return new Rect(0, 0, dstWidth, dstHeight);
        }
    }

我如何剪切或裁剪制作内容图像？

1 个答案: