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The middle\npeak disappears completely: Since there were no seed values in this peak\nregion, its reconstructed value is truncated to the surrounding value (-1).\n\nAs a more practical example, we try to extract the bright features of an\nimage by subtracting a background image created by reconstruction.\n\n" }, { "__type": "Code", "__tag": 4050, "value": "y, x = np.mgrid[:20:0.5, :20:0.5]\nbumps = np.sin(x) + np.sin(y)\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\nTo create the background image, set the mask image to the original image,\nand the seed image to the original image with an intensity offset, `h`.\n\n" }, { "__type": "Code", "__tag": 4050, "value": "h = 0.3\nseed = bumps - h\nbackground = reconstruction(seed, bumps)\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\nThe resulting reconstructed image looks exactly like the original image,\nbut with the peaks of the bumps cut off. Subtracting this reconstructed\nimage from the original image leaves just the peaks of the bumps\n\n" }, { "__type": "Code", "__tag": 4050, "value": "hdome = bumps - background\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\nThis operation is known as the h-dome of the image and leaves features\nof height `h` in the subtracted image." } ], "title": [], "level": 0, "target": null }, "see_also": [], "signature": { "__type": "SignatureNode", "__tag": 4029, "kind": "function", "parameters": [ { "__type": "SigParam", "__tag": 4030, "name": "seed", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": { "__type": "Empty", "__tag": 4031 } }, { "__type": "SigParam", "__tag": 4030, "name": "mask", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": { "__type": "Empty", "__tag": 4031 } }, { "__type": "SigParam", "__tag": 4030, "name": "method", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": "dilation" }, { "__type": "SigParam", "__tag": 4030, "name": "footprint", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": "None" }, { "__type": "SigParam", "__tag": 4030, "name": "offset", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": "None" } ], "return_annotation": { "__type": "Empty", "__tag": 4031 }, "target_name": "reconstruction" }, "references": [ ".. [1] Robinson, \"Efficient morphological reconstruction: a downhill", " filter\", Pattern Recognition Letters 25 (2004) 1759-1767.", ".. [2] Vincent, L., \"Morphological Grayscale Reconstruction in Image", " Analysis: Applications and Efficient Algorithms\", IEEE Transactions", " on Image Processing (1993)", ".. [3] Soille, P., \"Morphological Image Analysis: Principles and", " Applications\", Chapter 6, 2nd edition (2003), ISBN 3540429883." ], "qa": "skimage.morphology.grayreconstruct:reconstruction", "arbitrary": [], "local_refs": [ "footprint", "mask", "method", "offset", "reconstructed", "seed" ] }