/// <summary> /// Generates a circular mask to use in morphological operations /// with the anchor in the center /// </summary> /// <param name="radius">The radius of the mask as maximum distance from center pixel (i.e. radius=0 would be 1-pixel mask)</param> /// <returns>The mask</returns> public static MorphologyMask GenerateDiskMask(int radius) { if (radius < 1) { throw new ArgumentOutOfRangeException("radius"); } //Masks in ipps morphological functions don't really allow for stride //unless it is guaranteed, that the pixels within the stride are of value0 //therefore we generate the mask with the minimum possible width and height //that is dividable by 4 int diameter = 1 + 2 * radius;//center pixel is extra int imageWidth = (int)(Math.Ceiling(diameter / 4.0) * 4); IppiPoint center = new IppiPoint(radius, radius); Image8 mask = new Image8(imageWidth, diameter); //Set all pixels to 0 IppHelper.IppCheckCall(ip.ippiSet_8u_C1R(0, mask.Image, mask.Stride, mask.Size)); //Loop over pixels, check distance and set to 1 if within circle for (int x = 0; x < mask.Width; x++) { for (int y = 0; y < mask.Width; y++) { if (Distance.Euclidian(new IppiPoint(x, y), center) <= radius) { *mask[x, y] = 1; } } } //default anchor is in the circle's center return(new MorphologyMask(mask, center)); }
/// <summary> /// Performs a 3x3 opening operation on an image - removes speckles /// </summary> /// <param name="imIn">The image to perform an opening operation on</param> /// <param name="imOpened">The image after the opening operation</param> /// <param name="imCalc">Intermediate image for semi-processed version</param> /// <param name="region">The ROI in which to perform the operation</param> public static void Open3x3(Image8 imIn, Image8 imOpened, Image8 imCalc, IppiROI roi) { //Modify region we operate on to allow mask overhang var inner = new IppiROI(roi.X + 1, roi.Y + 1, roi.Width - 3, roi.Height - 3); IppHelper.IppCheckCall(ip.ippiErode3x3_8u_C1R(imIn[inner.TopLeft], imIn.Stride, imCalc[inner.TopLeft], imCalc.Stride, inner.Size)); IppHelper.IppCheckCall(ip.ippiDilate3x3_8u_C1R(imCalc[inner.TopLeft], imCalc.Stride, imOpened[inner.TopLeft], imOpened.Stride, inner.Size)); }
/// <summary> /// Performs an opening operation in the specified ROI using the specified /// neighborhood mask /// </summary> /// <param name="imIn">The image to perform the opening operation on</param> /// <param name="imOpened">The image after the opening operation</param> /// <param name="imCalc">Intermediate buffer for processing</param> /// <param name="neighborhood">The mask for the opening operation</param> /// <param name="region">The image region in which to perform the operation</param> public static void Open(Image8 imIn, Image8 imOpened, Image8 imCalc, MorphologyMask neighborhood, IppiROI roi) { //Modify region we operate on to allow mask overhang var inner = new IppiROI(roi.X + neighborhood.Anchor.x, roi.Y + neighborhood.Anchor.y, roi.Width - neighborhood.Mask.Width, roi.Height - neighborhood.Mask.Height); IppHelper.IppCheckCall(ip.ippiErode_8u_C1R(imIn[inner.TopLeft], imIn.Stride, imCalc[inner.TopLeft], imCalc.Stride, inner.Size, neighborhood.Mask.Image, neighborhood.Mask.Size, neighborhood.Anchor)); IppHelper.IppCheckCall(ip.ippiDilate_8u_C1R(imCalc[inner.TopLeft], imCalc.Stride, imOpened[inner.TopLeft], imOpened.Stride, inner.Size, neighborhood.Mask.Image, neighborhood.Mask.Size, neighborhood.Anchor)); }
/// <summary> /// Multiplies the mask with the image effectively removing /// parts outside the mask /// </summary> /// <param name="image">The image to mask</param> public void MaskImage(Image8 image) { if (!_maskValid) { GenerateMask(); } IppHelper.IppCheckCall(ip.ippiMul_8u_C1IRSfs(_mask.Image, _mask.Stride, image.Image, image.Stride, image.Size, 0)); }
public override void UpdateBackground(Image8 im) { if (im.Width != width || im.Height != height) { throw new ArgumentException("The supplied image must have the same dimensions as the background"); } IppHelper.IppCheckCall(cv.ippiAddWeighted_8u32f_C1IR(im.Image, im.Stride, background.Image, background.Stride, im.Size, FractionUpdate)); }
//Construct 32F image using an 8-bit unsigned image as input public Image32F(Image8 im) { Width = im.Width; Height = im.Height; Size = new IppiSize(Width, Height); Stride = 4 * Width; Image = (float *)Marshal.AllocHGlobal(Stride * Height).ToPointer(); //convert image IppHelper.IppCheckCall(ip.ippiConvert_8u32f_C1R(im.Image, im.Stride, Image, Stride, Size)); }
//Construct 16-bit image using an 8-bit unsigned image as input public Image16(Image8 im) { Width = im.Width; Height = im.Height; Size = new IppiSize(Width, Height); Stride = (int)(4 * Math.Ceiling(Width * 2 / 4.0)); Image = (ushort *)Marshal.AllocHGlobal(Stride * Height).ToPointer(); //scale, convert and copy image IppHelper.IppCheckCall(ip.ippiScale_8u16u_C1R(im.Image, im.Stride, Image, Stride, Size)); _isFromPinned = false; }
public virtual void UpdateBackground(Image8 im, BlobWithMoments regionToExclude) { if (regionToExclude == null) { UpdateBackground(im); } else { //reset our mask to <update all>, then fill bounding box with 0s ip.ippiSet_8u_C1R(byte.MaxValue, _updateMask.Image, _updateMask.Stride, _updateMask.Size); IppiROI roi = new IppiROI(regionToExclude.BoundingBox.x, regionToExclude.BoundingBox.y, regionToExclude.BoundingBox.width, regionToExclude.BoundingBox.height); ip.ippiSet_8u_C1R(0, _updateMask[regionToExclude.BB_TopLeft], _updateMask.Stride, regionToExclude.BB_Size); IppHelper.IppCheckCall(cv.ippiAddWeighted_8u32f_C1IMR(im.Image, im.Stride, _updateMask.Image, _updateMask.Stride, background.Image, background.Stride, im.Size, FractionUpdate)); } }
/// <summary> /// Generates a rectangular mask to use in morphological operations /// with the anchor in the center /// </summary> /// <param name="width">The width of the rectangle</param> /// <param name="height">The height of the rectangle</param> /// <returns>The morphology mask</returns> public static MorphologyMask GenerateRectMask(int width, int height) { if (width < 1) { throw new ArgumentOutOfRangeException("width"); } if (height < 1) { throw new ArgumentOutOfRangeException("height"); } int imageWidth = (int)(Math.Ceiling(width / 4.0) * 4); IppiPoint center = new IppiPoint((int)Math.Floor(width / 4.0), (int)Math.Floor(height / 4.0)); Image8 mask = new Image8(imageWidth, height); //Set all pixels to zero IppHelper.IppCheckCall(ip.ippiSet_8u_C1R(0, mask.Image, mask.Stride, mask.Size)); //Set rectangle to 1 IppHelper.IppCheckCall(ip.ippiSet_8u_C1R(1, mask.Image, mask.Stride, new IppiSize(width, height))); return(new MorphologyMask(mask, center)); }
/// <summary> /// Update background excluding detected regions from the update /// </summary> /// <param name="im">The new image to add to the background</param> /// <param name="regionsToExclude">The blobs that should be excluded from the update</param> public virtual void UpdateBackground(Image8 im, BlobWithMoments[] regionsToExclude) { if (regionsToExclude == null) { UpdateBackground(im); } else { //reset our mask to <update all>, then fill all bounding boxes with 0s ip.ippiSet_8u_C1R(byte.MaxValue, _updateMask.Image, _updateMask.Stride, _updateMask.Size); foreach (BlobWithMoments b in regionsToExclude) { if (b != null) { ip.ippiSet_8u_C1R(0, _updateMask[b.BB_TopLeft], _updateMask.Stride, b.BB_Size); } } IppHelper.IppCheckCall(cv.ippiAddWeighted_8u32f_C1IMR(im.Image, im.Stride, _updateMask.Image, _updateMask.Stride, background.Image, background.Stride, im.Size, FractionUpdate)); } }
public virtual void UpdateBackground(Image8 im, Blob[] regionsToExclude) { if (regionsToExclude == null)//do a simple update { UpdateBackground(im); } else { //reset our mask to <update all>, then fill all bounding boxes with 0s ip.ippiSet_8u_C1R(byte.MaxValue, _updateMask.Image, _updateMask.Stride, _updateMask.Size); foreach (Blob b in regionsToExclude) { if (b != null) { IppiROI roi = new IppiROI(b.BoundingBox); ip.ippiSet_8u_C1R(0, _updateMask[roi.TopLeft], _updateMask.Stride, roi.Size); } } IppHelper.IppCheckCall(cv.ippiAddWeighted_8u32f_C1IMR(im.Image, im.Stride, _updateMask.Image, _updateMask.Stride, background.Image, background.Stride, im.Size, FractionUpdate)); } }
/// <summary> /// Implements a "greater than" threshold like MATLABS /// im2bw function /// </summary> /// <param name="imIn">The image to threshold</param> /// <param name="imThresh">The image after thresholding</param> /// <param name="region">The ROI in which to perform the operation</param> /// <param name="threshold">The threshold to apply</param> public static void Im2Bw(Image8 imIn, Image8 imThresh, IppiROI region, byte threshold) { IppHelper.IppCheckCall(ip.ippiThreshold_LTVal_8u_C1R(imIn[region.TopLeft], imIn.Stride, imThresh[region.TopLeft], imThresh.Stride, region.Size, (byte)(threshold + 1), 0)); IppHelper.IppCheckCall(ip.ippiThreshold_GTVal_8u_C1IR(imThresh[region.TopLeft], imThresh.Stride, region.Size, threshold, 255)); }
void GenerateMask() { //To generate the mask, we use a euclidian distance transform to the center pixel //followed by a thresholding operation //To save resources we only do this within the outer square of the circle since //all pixels outside of that square will be black anyway double xStart, yStart; //compute outer square xStart = _center.x - _radius; yStart = _center.y - _radius; if (xStart < 0) { xStart = 0; } if (yStart < 0) { yStart = 0; } IppiROI outerSquare = new IppiROI((int)xStart, (int)yStart, 2 * _radius, 2 * _radius); if (outerSquare.X + outerSquare.Width >= _mask.Width) { outerSquare.Width = _mask.Width - outerSquare.X - 1; } if (outerSquare.Y + outerSquare.Height >= _mask.Height) { outerSquare.Height = _mask.Height - outerSquare.Y - 1; } //The distance transform will calculate for all non-0 pixels the distance to the closest //0 pixel - hence we set all pixels in our mask temporarily to 1 and the circles center to 0 IppHelper.IppCheckCall(ip.ippiSet_8u_C1R(1, _mask.Image, _mask.Stride, _mask.Size)); IppHelper.IppCheckCall(ip.ippiSet_8u_C1R(0, _mask[Center], _mask.Stride, new IppiSize(1, 1))); //initialize buffers and calculate distance transform within outer square //we initialize the distance transform image with a value > radius so that all the //untouched pixel outside of the outer square will later be set to 0 int bufferSize; IppHelper.IppCheckCall(cv.ippiTrueDistanceTransformGetBufferSize_8u32f_C1R(outerSquare.Size, &bufferSize)); byte * dTransBuffer = (byte *)Marshal.AllocHGlobal(bufferSize); Image32F distImage = new Image32F(_mask); IppHelper.IppCheckCall(ip.ippiSet_32f_C1R(Radius + 1, distImage.Image, distImage.Stride, distImage.Size)); IppHelper.IppCheckCall(cv.ippiTrueDistanceTransform_8u32f_C1R(_mask[outerSquare.TopLeft], _mask.Stride, distImage[outerSquare.TopLeft], distImage.Stride, outerSquare.Size, dTransBuffer)); //set all pixels whose value after the distance transform is >radius to 0 IppHelper.IppCheckCall(ip.ippiThreshold_GTVal_32f_C1IR(distImage.Image, distImage.Stride, distImage.Size, Radius, 0)); //now set all pixels whose value is >0 to 1 IppHelper.IppCheckCall(ip.ippiThreshold_GTVal_32f_C1IR(distImage.Image, distImage.Stride, distImage.Size, 0, 1)); //convert dist image, copying it into the mask IppHelper.IppCheckCall(ip.ippiConvert_32f8u_C1R(distImage.Image, distImage.Stride, _mask.Image, _mask.Stride, _mask.Size, IppRoundMode.ippRndNear)); //Clean up Marshal.FreeHGlobal((IntPtr)dTransBuffer); distImage.Dispose(); _maskValid = true; /* * //We want to generate the mask with the least amount of pixel-iterations possible * //based on the radius we can define to rectangular regions for which we can * //bulk-set the pixels * //The inner square of the circle is definitely white (centered around center, side-length = sqrt(r*r/2) * //The outer square is definitely black (centerered around center, side-length=radius) * double sideLength,xStart,yStart; * * //compute inner square * sideLength = Math.Sqrt(_radius * _radius / 2); * xStart = _center.x - sideLength / 2; * yStart = _center.y - sideLength / 2; * if (xStart < 0) * xStart = 0; * if (yStart < 0) * yStart = 0; * IppiROI innerSquare = new IppiROI((int)xStart, (int)yStart, (int)sideLength, (int)sideLength); * if (innerSquare.X + innerSquare.Width >= _mask.Width) * { * innerSquare.Width = _mask.Width - innerSquare.X - 1; * } * if (innerSquare.Y + innerSquare.Height >= _mask.Height) * { * innerSquare.Height = _mask.Height - innerSquare.Y - 1; * } * * //compute outer square * xStart = _center.x - _radius / 2.0; * yStart = _center.y - _radius / 2.0; * if (xStart < 0) * xStart = 0; * if (yStart < 0) * yStart = 0; * IppiROI outerSquare = new IppiROI((int)xStart, (int)yStart, _radius, _radius); * if (outerSquare.X + outerSquare.Width >= _mask.Width) * { * outerSquare.Width = _mask.Width - outerSquare.X - 1; * } * if (outerSquare.Y + outerSquare.Height >= _mask.Height) * { * outerSquare.Height = _mask.Height - outerSquare.Y - 1; * } * * //set whole image to black and inner square to 1 * IppHelper.IppCheckCall(ip.ippiSet_8u_C1R(0, _mask.Image, _mask.Stride, _mask.Size)); * IppHelper.IppCheckCall(ip.ippiSet_8u_C1R(1, _mask[innerSquare.TopLeft], _mask.Stride, innerSquare.Size)); * * //loop over all the pixels that are in between the boundaries of the outer * //and inner square, measure their distance to the center and * //p = d>r?0:1; */ }
/// <summary> /// Scale image to 8bit representation avoiding clipping /// </summary> /// <param name="im"></param> public void ReduceTo8U(Image8 im) { System.Diagnostics.Debug.Assert(im.Width == Width); System.Diagnostics.Debug.Assert(im.Height == Height); IppHelper.IppCheckCall(ip.ippiScale_16u8u_C1R(Image, Stride, im.Image, im.Stride, Size, IppHintAlgorithm.ippAlgHintFast)); }
public void ReduceTo8U(Image8 im) { System.Diagnostics.Debug.Assert(im.Width == Width); System.Diagnostics.Debug.Assert(im.Height == Height); IppHelper.IppCheckCall(ip.ippiConvert_32f8u_C1R(Image, Stride, im.Image, im.Stride, Size, IppRoundMode.ippRndZero)); }