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Notice the dark borders\naround the image, due to the zero-padding beyond its boundaries.\nThe `convolve2d` function allows for other types of image boundaries,\nbut is far slower.\n\n" }, { "__type": "Code", "__tag": 4050, "value": "from scipy import datasets\n", "execution_status": "success" }, { "__type": "Code", "__tag": 4050, "value": "face = datasets.face(gray=True)\n", "execution_status": "unexpected_exception" }, { "__type": "Code", "__tag": 4050, "value": "kernel = np.outer(signal.windows.gaussian(70, 8),\n signal.windows.gaussian(70, 8))\n", "execution_status": "success" }, { "__type": "Code", "__tag": 4050, "value": "blurred = signal.fftconvolve(face, kernel, mode='same')\n", "execution_status": "unexpected_exception" }, { "__type": "Text", "__tag": 4046, "value": "\n" }, { "__type": "Code", "__tag": 4050, "value": "fig, (ax_orig, ax_kernel, ax_blurred) = plt.subplots(3, 1,\n figsize=(6, 15))\n", "execution_status": "success" }, { "__type": "Code", "__tag": 4050, "value": "ax_orig.imshow(face, cmap='gray')\n", "execution_status": "unexpected_exception" }, { "__type": "Code", "__tag": 4050, "value": "ax_orig.set_title('Original')\n", "execution_status": "failure" }, { "__type": "Code", "__tag": 4050, "value": "ax_orig.set_axis_off()\n", "execution_status": "success" }, { "__type": "Code", "__tag": 4050, "value": "ax_kernel.imshow(kernel, cmap='gray')\nax_kernel.set_title('Gaussian kernel')\n", "execution_status": "failure" }, { "__type": "Code", "__tag": 4050, "value": "ax_kernel.set_axis_off()\n", "execution_status": "success" }, { "__type": "Code", "__tag": 4050, "value": "ax_blurred.imshow(blurred, cmap='gray')\n", "execution_status": "unexpected_exception" }, { "__type": "Code", "__tag": 4050, "value": "ax_blurred.set_title('Blurred')\n", "execution_status": "failure" }, { "__type": "Code", "__tag": 4050, "value": "ax_blurred.set_axis_off()\nfig.show()\n", "execution_status": "success" } ], "title": [], "level": 0, "target": null }, "see_also": [ { "__type": "SeeAlsoItem", "__tag": 4028, "name": { "__type": "CrossRef", "__tag": 4002, "value": "convolve", "reference": { "__type": "RefInfo", "__tag": 4000, "module": "current-module", "version": "current-version", "kind": "to-resolve", "path": "convolve" }, "kind": "module" }, "descriptions": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "Uses the direct convolution or FFT convolution algorithm depending on which is faster." } ] } ], "type": "func" }, { "__type": "SeeAlsoItem", "__tag": 4028, "name": { "__type": "CrossRef", "__tag": 4002, "value": "oaconvolve", "reference": { "__type": "LocalRef", "__tag": 4022, "kind": "module", "path": "scipy.signal._signaltools:oaconvolve" }, "kind": "module" }, "descriptions": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "Uses the overlap-add method to do convolution, which is generally faster when the input arrays are large and significantly different in size." } ] } ], "type": "func" } ], "signature": { "__type": "SignatureNode", "__tag": 4029, "kind": "function", "parameters": [ { "__type": "SigParam", "__tag": 4030, "name": "in1", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": { "__type": "Empty", "__tag": 4031 } }, { "__type": "SigParam", "__tag": 4030, "name": "in2", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": { "__type": "Empty", "__tag": 4031 } }, { "__type": "SigParam", "__tag": 4030, "name": "mode", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": "full" }, { "__type": "SigParam", "__tag": 4030, "name": "axes", "annotation": { "__type": "Empty", "__tag": 4031 }, "kind": "POSITIONAL_OR_KEYWORD", "default": "None" } ], "return_annotation": { "__type": "Empty", "__tag": 4031 }, "target_name": "fftconvolve" }, "references": null, "qa": "scipy.signal._signaltools:fftconvolve", "arbitrary": [], "local_refs": [ "axes", "in1", "in2", "mode", "out" ] }