public Bitmap getTransparentSignatureBitmap(boolean trimBlankSpace) {

        if (!trimBlankSpace) {
            return getTransparentSignatureBitmap();
        }

        ensureSignatureBitmap();

        int imgHeight = mSignatureBitmap.getHeight();
        int imgWidth = mSignatureBitmap.getWidth();

        int backgroundColor = Color.TRANSPARENT;

        int xMin = Integer.MAX_VALUE,
                xMax = Integer.MIN_VALUE,
                yMin = Integer.MAX_VALUE,
                yMax = Integer.MIN_VALUE;

        boolean foundPixel = false;

        // Find xMin
        for (int x = 0; x < imgWidth; x++) {
            boolean stop = false;
            for (int y = 0; y < imgHeight; y++) {
                if (mSignatureBitmap.getPixel(x, y) != backgroundColor) {
                    xMin = x;
                    stop = true;
                    foundPixel = true;
                    break;
                }
            }
            if (stop)
                break;
        }

        // Image is empty...
        if (!foundPixel)
            return null;

        // Find yMin
        for (int y = 0; y < imgHeight; y++) {
            boolean stop = false;
            for (int x = xMin; x < imgWidth; x++) {
                if (mSignatureBitmap.getPixel(x, y) != backgroundColor) {
                    yMin = y;
                    stop = true;
                    break;
                }
            }
            if (stop)
                break;
        }

        // Find xMax
        for (int x = imgWidth - 1; x >= xMin; x--) {
            boolean stop = false;
            for (int y = yMin; y < imgHeight; y++) {
                if (mSignatureBitmap.getPixel(x, y) != backgroundColor) {
                    xMax = x;
                    stop = true;
                    break;
                }
            }
            if (stop)
                break;
        }

        // Find yMax
        for (int y = imgHeight - 1; y >= yMin; y--) {
            boolean stop = false;
            for (int x = xMin; x <= xMax; x++) {
                if (mSignatureBitmap.getPixel(x, y) != backgroundColor) {
                    yMax = y;
                    stop = true;
                    break;
                }
            }
            if (stop)
                break;
        }

        return Bitmap.createBitmap(mSignatureBitmap, xMin, yMin, xMax - xMin, yMax - yMin);
    }
Set the velocity filter weight.

@param velocityFilterWeight the weight.
signature-pad/src/main/java/com/github/gcacace/signaturepad/views/SignaturePad.java