在ImageView上绘图

时间:2013-09-06 05:43:11

标签: java android image bitmap imageview

我找到了一些绘制直方图的代码但我不确定如果用户点击_tempBitmaps[0]按钮

后如何显示ShowRGB Histogram的直方图

我希望用户点击按钮ImageView后,图表会显示在display_RGB之上,当用户再次点击该按钮时,图表就会消失。

我还附上了我希望实现的布局和图形的模型。

样机:

Mockup

以下是我为直方图找到的示例代码,它可以正常工作,但目前有些变量尚未初始化,这就是我需要帮助的地方:

class DrawOnTop extends View {
    Bitmap mBitmap;
    Paint mPaintBlack;
    Paint mPaintYellow;
    Paint mPaintRed;
    Paint mPaintGreen;
    Paint mPaintBlue;
    byte[] mYUVData;
    int[] mRGBData;
    int mImageWidth, mImageHeight;
    int[] mRedHistogram;
    int[] mGreenHistogram;
    int[] mBlueHistogram;
    double[] mBinSquared;

    public DrawOnTop(Context context) {
        super(context);

        mPaintBlack = new Paint();
        mPaintBlack.setStyle(Paint.Style.FILL);
        mPaintBlack.setColor(Color.BLACK);
        mPaintBlack.setTextSize(25);

        mPaintYellow = new Paint();
        mPaintYellow.setStyle(Paint.Style.FILL);
        mPaintYellow.setColor(Color.YELLOW);
        mPaintYellow.setTextSize(25);

        mPaintRed = new Paint();
        mPaintRed.setStyle(Paint.Style.FILL);
        mPaintRed.setColor(Color.RED);
        mPaintRed.setTextSize(25);

        mPaintGreen = new Paint();
        mPaintGreen.setStyle(Paint.Style.FILL);
        mPaintGreen.setColor(Color.GREEN);
        mPaintGreen.setTextSize(25);

        mPaintBlue = new Paint();
        mPaintBlue.setStyle(Paint.Style.FILL);
        mPaintBlue.setColor(Color.BLUE);
        mPaintBlue.setTextSize(25);

        mBitmap = null;
        mYUVData = null;
        mRGBData = null;
        mRedHistogram = new int[256];
        mGreenHistogram = new int[256];
        mBlueHistogram = new int[256];
        mBinSquared = new double[256];
        for (int bin = 0; bin < 256; bin++)
        {
            mBinSquared[bin] = ((double)bin) * bin;
        } // bin
    }

    @Override
    protected void onDraw(Canvas canvas) {
        if (mBitmap != null)
        {
            int canvasWidth = canvas.getWidth();
            int canvasHeight = canvas.getHeight();
            int newImageWidth = canvasWidth;
            int newImageHeight = canvasHeight;
            int marginWidth = (canvasWidth - newImageWidth)/2;

            // Convert from YUV to RGB
            decodeYUV420SP(mRGBData, mYUVData, mImageWidth, mImageHeight);

            // Draw bitmap
            mBitmap.setPixels(mRGBData, 0, mImageWidth, 0, 0, 
                    mImageWidth, mImageHeight);
            Rect src = new Rect(0, 0, mImageWidth, mImageHeight);
            Rect dst = new Rect(marginWidth, 0, 
                    canvasWidth-marginWidth, canvasHeight);
            canvas.drawBitmap(mBitmap, src, dst, mPaintBlack);

            // Draw black borders                       
            canvas.drawRect(0, 0, marginWidth, canvasHeight, mPaintBlack);
            canvas.drawRect(canvasWidth - marginWidth, 0, 
                    canvasWidth, canvasHeight, mPaintBlack);

            // Calculate histogram
            calculateIntensityHistogram(mRGBData, mRedHistogram, 
                    mImageWidth, mImageHeight, 0);
            calculateIntensityHistogram(mRGBData, mGreenHistogram, 
                    mImageWidth, mImageHeight, 1);
            calculateIntensityHistogram(mRGBData, mBlueHistogram, 
                    mImageWidth, mImageHeight, 2);

            // Calculate mean
            double imageRedMean = 0, imageGreenMean = 0, imageBlueMean = 0;
            double redHistogramSum = 0, greenHistogramSum = 0, blueHistogramSum = 0;
            for (int bin = 0; bin < 256; bin++)
            {
                imageRedMean += mRedHistogram[bin] * bin;
                redHistogramSum += mRedHistogram[bin];
                imageGreenMean += mGreenHistogram[bin] * bin;
                greenHistogramSum += mGreenHistogram[bin];
                imageBlueMean += mBlueHistogram[bin] * bin;
                blueHistogramSum += mBlueHistogram[bin];
            } // bin
            imageRedMean /= redHistogramSum;
            imageGreenMean /= greenHistogramSum;
            imageBlueMean /= blueHistogramSum;

            // Calculate second moment
            double imageRed2ndMoment = 0, imageGreen2ndMoment = 0, imageBlue2ndMoment = 0;
            for (int bin = 0; bin < 256; bin++)
            {
                imageRed2ndMoment += mRedHistogram[bin] * mBinSquared[bin];
                imageGreen2ndMoment += mGreenHistogram[bin] * mBinSquared[bin];
                imageBlue2ndMoment += mBlueHistogram[bin] * mBinSquared[bin];
            } // bin
            imageRed2ndMoment /= redHistogramSum;
            imageGreen2ndMoment /= greenHistogramSum;
            imageBlue2ndMoment /= blueHistogramSum;
            double imageRedStdDev = Math.sqrt( imageRed2ndMoment - imageRedMean*imageRedMean );
            double imageGreenStdDev = Math.sqrt( imageGreen2ndMoment - imageGreenMean*imageGreenMean );
            double imageBlueStdDev = Math.sqrt( imageBlue2ndMoment - imageBlueMean*imageBlueMean );

            // Draw mean
            String imageMeanStr = "Mean (R,G,B): " + String.format("%.4g", imageRedMean) + ", " + String.format("%.4g", imageGreenMean) + ", " + String.format("%.4g", imageBlueMean);
            canvas.drawText(imageMeanStr, marginWidth+10-1, 30-1, mPaintBlack);
            canvas.drawText(imageMeanStr, marginWidth+10+1, 30-1, mPaintBlack);
            canvas.drawText(imageMeanStr, marginWidth+10+1, 30+1, mPaintBlack);
            canvas.drawText(imageMeanStr, marginWidth+10-1, 30+1, mPaintBlack);
            canvas.drawText(imageMeanStr, marginWidth+10, 30, mPaintYellow);

            // Draw standard deviation
            String imageStdDevStr = "Std Dev (R,G,B): " + String.format("%.4g", imageRedStdDev) + ", " + String.format("%.4g", imageGreenStdDev) + ", " + String.format("%.4g", imageBlueStdDev);
            canvas.drawText(imageStdDevStr, marginWidth+10-1, 60-1, mPaintBlack);
            canvas.drawText(imageStdDevStr, marginWidth+10+1, 60-1, mPaintBlack);
            canvas.drawText(imageStdDevStr, marginWidth+10+1, 60+1, mPaintBlack);
            canvas.drawText(imageStdDevStr, marginWidth+10-1, 60+1, mPaintBlack);
            canvas.drawText(imageStdDevStr, marginWidth+10, 60, mPaintYellow);

            // Draw red intensity histogram
            float barMaxHeight = 3000;
            float barWidth = ((float)newImageWidth) / 256;
            float barMarginHeight = 2;
            RectF barRect = new RectF();
            barRect.bottom = canvasHeight - 200;
            barRect.left = marginWidth;
            barRect.right = barRect.left + barWidth;
            for (int bin = 0; bin < 256; bin++)
            {
                float prob = (float)mRedHistogram[bin] / (float)redHistogramSum;
                barRect.top = barRect.bottom - 
                    Math.min(80,prob*barMaxHeight) - barMarginHeight;
                canvas.drawRect(barRect, mPaintBlack);
                barRect.top += barMarginHeight;
                canvas.drawRect(barRect, mPaintRed);
                barRect.left += barWidth;
                barRect.right += barWidth;
            } // bin

            // Draw green intensity histogram
            barRect.bottom = canvasHeight - 100;
            barRect.left = marginWidth;
            barRect.right = barRect.left + barWidth;
            for (int bin = 0; bin < 256; bin++)
            {
                barRect.top = barRect.bottom - Math.min(80, ((float)mGreenHistogram[bin])/((float)greenHistogramSum) * barMaxHeight) - barMarginHeight;
                canvas.drawRect(barRect, mPaintBlack);
                barRect.top += barMarginHeight;
                canvas.drawRect(barRect, mPaintGreen);
                barRect.left += barWidth;
                barRect.right += barWidth;
            } // bin

            // Draw blue intensity histogram
            barRect.bottom = canvasHeight;
            barRect.left = marginWidth;
            barRect.right = barRect.left + barWidth;
            for (int bin = 0; bin < 256; bin++)
            {
                barRect.top = barRect.bottom - Math.min(80, ((float)mBlueHistogram[bin])/((float)blueHistogramSum) * barMaxHeight) - barMarginHeight;
                canvas.drawRect(barRect, mPaintBlack);
                barRect.top += barMarginHeight;
                canvas.drawRect(barRect, mPaintBlue);
                barRect.left += barWidth;
                barRect.right += barWidth;
            } // bin
        } // end if statement

        super.onDraw(canvas);

    } // end onDraw method

    static public void decodeYUV420SP(int[] rgb, byte[] yuv420sp, int width, int height) {
        final int frameSize = width * height;

        for (int j = 0, yp = 0; j < height; j++) {
            int uvp = frameSize + (j >> 1) * width, u = 0, v = 0;
            for (int i = 0; i < width; i++, yp++) {
                int y = (0xff & ((int) yuv420sp[yp])) - 16;
                if (y < 0) y = 0;
                if ((i & 1) == 0) {
                    v = (0xff & yuv420sp[uvp++]) - 128;
                    u = (0xff & yuv420sp[uvp++]) - 128;
                }

                int y1192 = 1192 * y;
                int r = (y1192 + 1634 * v);
                int g = (y1192 - 833 * v - 400 * u);
                int b = (y1192 + 2066 * u);

                if (r < 0) r = 0; else if (r > 262143) r = 262143;
                if (g < 0) g = 0; else if (g > 262143) g = 262143;
                if (b < 0) b = 0; else if (b > 262143) b = 262143;

                rgb[yp] = 0xff000000 | ((r << 6) & 0xff0000) | ((g >> 2) & 0xff00) | ((b >> 10) & 0xff);
            }
        }
    }

    static public void decodeYUV420SPGrayscale(int[] rgb, byte[] yuv420sp, int width, int height)
    {
        final int frameSize = width * height;

        for (int pix = 0; pix < frameSize; pix++)
        {
            int pixVal = (0xff & ((int) yuv420sp[pix])) - 16;
            if (pixVal < 0) pixVal = 0;
            if (pixVal > 255) pixVal = 255;
            rgb[pix] = 0xff000000 | (pixVal << 16) | (pixVal << 8) | pixVal;
        } // pix
    }

    static public void calculateIntensityHistogram(int[] rgb, int[] histogram, int width, int height, int component)
    {
        for (int bin = 0; bin < 256; bin++)
        {
            histogram[bin] = 0;
        } // bin
        if (component == 0) // red
        {
            for (int pix = 0; pix < width*height; pix += 3)
            {
                int pixVal = (rgb[pix] >> 16) & 0xff;
                histogram[ pixVal ]++;
            } // pix
        }
        else if (component == 1) // green
        {
            for (int pix = 0; pix < width*height; pix += 3)
            {
                int pixVal = (rgb[pix] >> 8) & 0xff;
                histogram[ pixVal ]++;
            } // pix
        }
        else // blue
        {
            for (int pix = 0; pix < width*height; pix += 3)
            {
                int pixVal = rgb[pix] & 0xff;
                histogram[ pixVal ]++;
            } // pix
        }
    }
} 

这是我想创建按钮的类,它将创建直方图:

public class testrgb extends Activity {
    /************************
     * PROPERTIES
     **********************/
    /* Tag for Log */
    public static final String TAG = "PiccaFinal.EditPicturesActivity";
    /* Images Path */
    private String[] _imagesPath;
    /* Original Images */
    private Bitmap[] _originalBitmaps = new Bitmap[2];
    /* Final Filtered Images */
    private Bitmap[] _filteredBitmaps = new Bitmap[2];

    /* Image View */
    private ImageView _filterImageView;

    private Preview mPreview;
    private DrawOnTop mDrawOnTop;


    int[] pixels;

    /************************
     * ANDROID METHODS
     **********************/
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getWindow().setFormat(PixelFormat.TRANSLUCENT);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.activity_edit_pictures);

        Intent intent = getIntent();
        _imagesPath = intent.getStringArrayExtra(MainActivity.IMAGES_PATH);

        for (int i = MainActivity.LEFT_IMAGE; i <= MainActivity.RIGHT_IMAGE; i++) {
            _originalBitmaps[i] = BitmapFactory.decodeFile(_imagesPath[i]);
        }

        _filterImageView = (ImageView) findViewById(R.id.filter_image_view);
        _filterImageView
                .setImageBitmap(_originalBitmaps[MainActivity.LEFT_IMAGE]);

        // --------------------------------------------------------------------------------

        // display_RGB

        Button display_RGBButton = (Button) findViewById(R.id.display_RGB);
        display_RGBButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                //what should I do here




        });

    }

}

0 个答案:

没有答案