{"id":105,"date":"2021-12-06T12:48:12","date_gmt":"2021-12-06T17:48:12","guid":{"rendered":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/?post_type=chapter&#038;p=105"},"modified":"2024-01-09T17:32:45","modified_gmt":"2024-01-09T22:32:45","slug":"image-start-the-chapter","status":"web-only","type":"chapter","link":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/chapter\/image-start-the-chapter\/","title":{"raw":"Image start the chapter","rendered":"Image start the chapter"},"content":{"raw":"<a id=\"anchor\"><\/a>\r\n<img class=\"aligncenter wp-image-106 \" src=\"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-content\/uploads\/sites\/998\/2021\/12\/Screenshot-2021-12-06-at-9.21.35-AM.png\" alt=\"\" width=\"773\" height=\"331\" \/>\r\n\r\nText for this chapter\r\n\r\nIn\u00a0<a title=\"Mathematics\" href=\"https:\/\/en.wikipedia.org\/wiki\/Mathematics\">mathematics<\/a>\u00a0(in particular,\u00a0<a title=\"Functional analysis\" href=\"https:\/\/en.wikipedia.org\/wiki\/Functional_analysis\">functional analysis<\/a>),\u00a0<b>convolution<\/b>\u00a0is a\u00a0<a title=\"Operation (mathematics)\" href=\"https:\/\/en.wikipedia.org\/wiki\/Operation_(mathematics)\">mathematical operation<\/a>\u00a0on two\u00a0<a title=\"Function (mathematics)\" href=\"https:\/\/en.wikipedia.org\/wiki\/Function_(mathematics)\">functions<\/a>\u00a0(<span class=\"texhtml mvar\">f<\/span>\u00a0and\u00a0<span class=\"texhtml mvar\">g<\/span>) that produces a third function (<span class=\"mwe-math-element\"><span class=\"mwe-math-mathml-inline mwe-math-mathml-a11y\">{\\displaystyle f*g}<\/span><img class=\"mwe-math-fallback-image-inline\" src=\"https:\/\/wikimedia.org\/api\/rest_v1\/media\/math\/render\/svg\/de088e4a3777d3b5d2787fdec81acd91e78a719e\" alt=\"f*g\" aria-hidden=\"true\" \/><\/span>) that expresses how the shape of one is modified by the other. The term\u00a0<i>convolution<\/i>\u00a0refers to both the result function and to the process of computing it. It is defined as the\u00a0<a title=\"Integral\" href=\"https:\/\/en.wikipedia.org\/wiki\/Integral\">integral<\/a>\u00a0of the product of the two functions after one is reversed and shifted. The integral is evaluated for all values of shift, producing the convolution function.\r\n\r\nSome features of convolution are similar to\u00a0<a title=\"Cross-correlation\" href=\"https:\/\/en.wikipedia.org\/wiki\/Cross-correlation\">cross-correlation<\/a>: for real-valued functions, of a continuous or discrete variable, it differs from cross-correlation (<span class=\"mwe-math-element\"><span class=\"mwe-math-mathml-inline mwe-math-mathml-a11y\">{\\displaystyle f\\star g}<\/span><img class=\"mwe-math-fallback-image-inline\" src=\"https:\/\/wikimedia.org\/api\/rest_v1\/media\/math\/render\/svg\/371d3161cd7e094182a184d7601b49880228385c\" alt=\"f\\star g\" aria-hidden=\"true\" \/><\/span>) only in that either\u00a0<span class=\"texhtml\"><i>f<\/i>(<i>x<\/i>)<\/span>\u00a0or\u00a0<span class=\"texhtml\"><i>g<\/i>(<i>x<\/i>)<\/span>\u00a0is reflected about the y-axis; thus it is a cross-correlation of\u00a0<span class=\"texhtml\"><i>f<\/i>(<i>x<\/i>)<\/span>\u00a0and\u00a0<span class=\"texhtml\"><i>g<\/i>(\u2212<i>x<\/i>)<\/span>, or\u00a0<span class=\"texhtml\"><i>f<\/i>(\u2212<i>x<\/i>)<\/span>\u00a0and\u00a0<span class=\"texhtml\"><i>g<\/i>(<i>x<\/i>)<\/span>.<sup id=\"cite_ref-1\" class=\"reference\"><a href=\"https:\/\/en.wikipedia.org\/wiki\/Convolution#cite_note-1\">[A]<\/a><\/sup>\u00a0 For complex-valued functions, the cross-correlation operator is the\u00a0<a title=\"Hermitian adjoint\" href=\"https:\/\/en.wikipedia.org\/wiki\/Hermitian_adjoint\">adjoint<\/a>\u00a0of the convolution operator.\r\n\r\nConvolution has applications that include\u00a0<a title=\"Probability\" href=\"https:\/\/en.wikipedia.org\/wiki\/Probability\">probability<\/a>,\u00a0<a title=\"Statistics\" href=\"https:\/\/en.wikipedia.org\/wiki\/Statistics\">statistics<\/a>,\u00a0<a title=\"Acoustics\" href=\"https:\/\/en.wikipedia.org\/wiki\/Acoustics\">acoustics<\/a>,\u00a0<a title=\"Spectroscopy\" href=\"https:\/\/en.wikipedia.org\/wiki\/Spectroscopy\">spectroscopy<\/a>,\u00a0<a title=\"Signal processing\" href=\"https:\/\/en.wikipedia.org\/wiki\/Signal_processing\">signal processing<\/a>\u00a0and\u00a0<a class=\"mw-redirect\" title=\"Image processing\" href=\"https:\/\/en.wikipedia.org\/wiki\/Image_processing\">image processing<\/a>,\u00a0<a title=\"Geophysics\" href=\"https:\/\/en.wikipedia.org\/wiki\/Geophysics\">geophysics<\/a>,\u00a0<a title=\"Engineering\" href=\"https:\/\/en.wikipedia.org\/wiki\/Engineering\">engineering<\/a>,\u00a0<a title=\"Physics\" href=\"https:\/\/en.wikipedia.org\/wiki\/Physics\">physics<\/a>,\u00a0<a title=\"Computer vision\" href=\"https:\/\/en.wikipedia.org\/wiki\/Computer_vision\">computer vision<\/a>\u00a0and\u00a0<a class=\"mw-redirect\" title=\"Differential equations\" href=\"https:\/\/en.wikipedia.org\/wiki\/Differential_equations\">differential equations<\/a>.<sup id=\"cite_ref-2\" class=\"reference\"><a href=\"https:\/\/en.wikipedia.org\/wiki\/Convolution#cite_note-2\">[1]<\/a><\/sup>\r\n\r\nThe convolution can be defined for functions on\u00a0<a title=\"Euclidean space\" href=\"https:\/\/en.wikipedia.org\/wiki\/Euclidean_space\">Euclidean space<\/a>\u00a0and other\u00a0<a title=\"Group (mathematics)\" href=\"https:\/\/en.wikipedia.org\/wiki\/Group_(mathematics)\">groups<\/a>.<sup class=\"noprint Inline-Template Template-Fact\">[<i><a title=\"Wikipedia:Citation needed\" href=\"https:\/\/en.wikipedia.org\/wiki\/Wikipedia:Citation_needed\"><span title=\"This claim needs references to reliable sources. (October 2017)\">citation needed<\/span><\/a><\/i>]<\/sup>\u00a0For example,\u00a0<a title=\"Periodic function\" href=\"https:\/\/en.wikipedia.org\/wiki\/Periodic_function\">periodic functions<\/a>, such as the\u00a0<a title=\"Discrete-time Fourier transform\" href=\"https:\/\/en.wikipedia.org\/wiki\/Discrete-time_Fourier_transform\">discrete-time Fourier transform<\/a>, can be defined on a\u00a0<a title=\"Circle\" href=\"https:\/\/en.wikipedia.org\/wiki\/Circle\">circle<\/a>\u00a0and convolved by\u00a0<a class=\"mw-redirect\" title=\"Periodic convolution\" href=\"https:\/\/en.wikipedia.org\/wiki\/Periodic_convolution\">periodic convolution<\/a>. (See row 18 at\u00a0<a class=\"mw-redirect\" title=\"DTFT\" href=\"https:\/\/en.wikipedia.org\/wiki\/DTFT#Properties\">DTFT \u00a7\u00a0Properties<\/a>.) A\u00a0<i>discrete convolution<\/i>\u00a0can be defined for functions on the set of\u00a0<a class=\"mw-redirect\" title=\"Integers\" href=\"https:\/\/en.wikipedia.org\/wiki\/Integers\">integers<\/a>.\r\n\r\nGeneralizations of convolution have applications in the field of\u00a0<a title=\"Numerical analysis\" href=\"https:\/\/en.wikipedia.org\/wiki\/Numerical_analysis\">numerical analysis<\/a>\u00a0and\u00a0<a title=\"Numerical linear algebra\" href=\"https:\/\/en.wikipedia.org\/wiki\/Numerical_linear_algebra\">numerical linear algebra<\/a>, and in the design and implementation of\u00a0<a title=\"Finite impulse response\" href=\"https:\/\/en.wikipedia.org\/wiki\/Finite_impulse_response\">finite impulse response<\/a>\u00a0filters in signal processing.<sup class=\"noprint Inline-Template Template-Fact\">[<i><a title=\"Wikipedia:Citation needed\" href=\"https:\/\/en.wikipedia.org\/wiki\/Wikipedia:Citation_needed\"><span title=\"This claim needs references to reliable sources. (October 2017)\">citation needed<\/span><\/a><\/i>]<\/sup>\r\n\r\nComputing the\u00a0<a title=\"Inverse function\" href=\"https:\/\/en.wikipedia.org\/wiki\/Inverse_function\">inverse<\/a>\u00a0of the convolution operation is known as\u00a0<a title=\"Deconvolution\" href=\"https:\/\/en.wikipedia.org\/wiki\/Deconvolution\">deconvolution<\/a>.\r\n\r\nSource: <a href=\"https:\/\/en.wikipedia.org\/wiki\/Convolution\">https:\/\/en.wikipedia.org\/wiki\/Convolution<\/a>\r\n\r\nPlace an <a href=\"#anchor\">anchor<\/a>","rendered":"<p><a id=\"anchor\"><\/a><br \/>\n<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-106\" src=\"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-content\/uploads\/sites\/998\/2021\/12\/Screenshot-2021-12-06-at-9.21.35-AM.png\" alt=\"\" width=\"773\" height=\"331\" srcset=\"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-content\/uploads\/sites\/998\/2021\/12\/Screenshot-2021-12-06-at-9.21.35-AM.png 1426w, https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-content\/uploads\/sites\/998\/2021\/12\/Screenshot-2021-12-06-at-9.21.35-AM-300x128.png 300w, https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-content\/uploads\/sites\/998\/2021\/12\/Screenshot-2021-12-06-at-9.21.35-AM-1024x438.png 1024w, https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-content\/uploads\/sites\/998\/2021\/12\/Screenshot-2021-12-06-at-9.21.35-AM-768x329.png 768w, https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-content\/uploads\/sites\/998\/2021\/12\/Screenshot-2021-12-06-at-9.21.35-AM-65x28.png 65w, https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-content\/uploads\/sites\/998\/2021\/12\/Screenshot-2021-12-06-at-9.21.35-AM-225x96.png 225w, https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-content\/uploads\/sites\/998\/2021\/12\/Screenshot-2021-12-06-at-9.21.35-AM-350x150.png 350w\" sizes=\"auto, (max-width: 773px) 100vw, 773px\" \/><\/p>\n<p>Text for this chapter<\/p>\n<p>In\u00a0<a title=\"Mathematics\" href=\"https:\/\/en.wikipedia.org\/wiki\/Mathematics\">mathematics<\/a>\u00a0(in particular,\u00a0<a title=\"Functional analysis\" href=\"https:\/\/en.wikipedia.org\/wiki\/Functional_analysis\">functional analysis<\/a>),\u00a0<b>convolution<\/b>\u00a0is a\u00a0<a title=\"Operation (mathematics)\" href=\"https:\/\/en.wikipedia.org\/wiki\/Operation_(mathematics)\">mathematical operation<\/a>\u00a0on two\u00a0<a title=\"Function (mathematics)\" href=\"https:\/\/en.wikipedia.org\/wiki\/Function_(mathematics)\">functions<\/a>\u00a0(<span class=\"texhtml mvar\">f<\/span>\u00a0and\u00a0<span class=\"texhtml mvar\">g<\/span>) that produces a third function (<span class=\"mwe-math-element\"><span class=\"mwe-math-mathml-inline mwe-math-mathml-a11y\">{\\displaystyle f*g}<\/span><img decoding=\"async\" class=\"mwe-math-fallback-image-inline\" src=\"https:\/\/wikimedia.org\/api\/rest_v1\/media\/math\/render\/svg\/de088e4a3777d3b5d2787fdec81acd91e78a719e\" alt=\"f*g\" aria-hidden=\"true\" \/><\/span>) that expresses how the shape of one is modified by the other. The term\u00a0<i>convolution<\/i>\u00a0refers to both the result function and to the process of computing it. It is defined as the\u00a0<a title=\"Integral\" href=\"https:\/\/en.wikipedia.org\/wiki\/Integral\">integral<\/a>\u00a0of the product of the two functions after one is reversed and shifted. The integral is evaluated for all values of shift, producing the convolution function.<\/p>\n<p>Some features of convolution are similar to\u00a0<a title=\"Cross-correlation\" href=\"https:\/\/en.wikipedia.org\/wiki\/Cross-correlation\">cross-correlation<\/a>: for real-valued functions, of a continuous or discrete variable, it differs from cross-correlation (<span class=\"mwe-math-element\"><span class=\"mwe-math-mathml-inline mwe-math-mathml-a11y\">{\\displaystyle f\\star g}<\/span><img decoding=\"async\" class=\"mwe-math-fallback-image-inline\" src=\"https:\/\/wikimedia.org\/api\/rest_v1\/media\/math\/render\/svg\/371d3161cd7e094182a184d7601b49880228385c\" alt=\"f\\star g\" aria-hidden=\"true\" \/><\/span>) only in that either\u00a0<span class=\"texhtml\"><i>f<\/i>(<i>x<\/i>)<\/span>\u00a0or\u00a0<span class=\"texhtml\"><i>g<\/i>(<i>x<\/i>)<\/span>\u00a0is reflected about the y-axis; thus it is a cross-correlation of\u00a0<span class=\"texhtml\"><i>f<\/i>(<i>x<\/i>)<\/span>\u00a0and\u00a0<span class=\"texhtml\"><i>g<\/i>(\u2212<i>x<\/i>)<\/span>, or\u00a0<span class=\"texhtml\"><i>f<\/i>(\u2212<i>x<\/i>)<\/span>\u00a0and\u00a0<span class=\"texhtml\"><i>g<\/i>(<i>x<\/i>)<\/span>.<sup id=\"cite_ref-1\" class=\"reference\"><a href=\"https:\/\/en.wikipedia.org\/wiki\/Convolution#cite_note-1\">[A]<\/a><\/sup>\u00a0 For complex-valued functions, the cross-correlation operator is the\u00a0<a title=\"Hermitian adjoint\" href=\"https:\/\/en.wikipedia.org\/wiki\/Hermitian_adjoint\">adjoint<\/a>\u00a0of the convolution operator.<\/p>\n<p>Convolution has applications that include\u00a0<a title=\"Probability\" href=\"https:\/\/en.wikipedia.org\/wiki\/Probability\">probability<\/a>,\u00a0<a title=\"Statistics\" href=\"https:\/\/en.wikipedia.org\/wiki\/Statistics\">statistics<\/a>,\u00a0<a title=\"Acoustics\" href=\"https:\/\/en.wikipedia.org\/wiki\/Acoustics\">acoustics<\/a>,\u00a0<a title=\"Spectroscopy\" href=\"https:\/\/en.wikipedia.org\/wiki\/Spectroscopy\">spectroscopy<\/a>,\u00a0<a title=\"Signal processing\" href=\"https:\/\/en.wikipedia.org\/wiki\/Signal_processing\">signal processing<\/a>\u00a0and\u00a0<a class=\"mw-redirect\" title=\"Image processing\" href=\"https:\/\/en.wikipedia.org\/wiki\/Image_processing\">image processing<\/a>,\u00a0<a title=\"Geophysics\" href=\"https:\/\/en.wikipedia.org\/wiki\/Geophysics\">geophysics<\/a>,\u00a0<a title=\"Engineering\" href=\"https:\/\/en.wikipedia.org\/wiki\/Engineering\">engineering<\/a>,\u00a0<a title=\"Physics\" href=\"https:\/\/en.wikipedia.org\/wiki\/Physics\">physics<\/a>,\u00a0<a title=\"Computer vision\" href=\"https:\/\/en.wikipedia.org\/wiki\/Computer_vision\">computer vision<\/a>\u00a0and\u00a0<a class=\"mw-redirect\" title=\"Differential equations\" href=\"https:\/\/en.wikipedia.org\/wiki\/Differential_equations\">differential equations<\/a>.<sup id=\"cite_ref-2\" class=\"reference\"><a href=\"https:\/\/en.wikipedia.org\/wiki\/Convolution#cite_note-2\">[1]<\/a><\/sup><\/p>\n<p>The convolution can be defined for functions on\u00a0<a title=\"Euclidean space\" href=\"https:\/\/en.wikipedia.org\/wiki\/Euclidean_space\">Euclidean space<\/a>\u00a0and other\u00a0<a title=\"Group (mathematics)\" href=\"https:\/\/en.wikipedia.org\/wiki\/Group_(mathematics)\">groups<\/a>.<sup class=\"noprint Inline-Template Template-Fact\">[<i><a title=\"Wikipedia:Citation needed\" href=\"https:\/\/en.wikipedia.org\/wiki\/Wikipedia:Citation_needed\"><span title=\"This claim needs references to reliable sources. (October 2017)\">citation needed<\/span><\/a><\/i>]<\/sup>\u00a0For example,\u00a0<a title=\"Periodic function\" href=\"https:\/\/en.wikipedia.org\/wiki\/Periodic_function\">periodic functions<\/a>, such as the\u00a0<a title=\"Discrete-time Fourier transform\" href=\"https:\/\/en.wikipedia.org\/wiki\/Discrete-time_Fourier_transform\">discrete-time Fourier transform<\/a>, can be defined on a\u00a0<a title=\"circle\" href=\"https:\/\/en.wikipedia.org\/wiki\/Circle\">circle<\/a>\u00a0and convolved by\u00a0<a class=\"mw-redirect\" title=\"Periodic convolution\" href=\"https:\/\/en.wikipedia.org\/wiki\/Periodic_convolution\">periodic convolution<\/a>. (See row 18 at\u00a0<a class=\"mw-redirect\" title=\"DTFT\" href=\"https:\/\/en.wikipedia.org\/wiki\/DTFT#Properties\">DTFT \u00a7\u00a0Properties<\/a>.) A\u00a0<i>discrete convolution<\/i>\u00a0can be defined for functions on the set of\u00a0<a class=\"mw-redirect\" title=\"Integers\" href=\"https:\/\/en.wikipedia.org\/wiki\/Integers\">integers<\/a>.<\/p>\n<p>Generalizations of convolution have applications in the field of\u00a0<a title=\"Numerical analysis\" href=\"https:\/\/en.wikipedia.org\/wiki\/Numerical_analysis\">numerical analysis<\/a>\u00a0and\u00a0<a title=\"Numerical linear algebra\" href=\"https:\/\/en.wikipedia.org\/wiki\/Numerical_linear_algebra\">numerical linear algebra<\/a>, and in the design and implementation of\u00a0<a title=\"Finite impulse response\" href=\"https:\/\/en.wikipedia.org\/wiki\/Finite_impulse_response\">finite impulse response<\/a>\u00a0filters in signal processing.<sup class=\"noprint Inline-Template Template-Fact\">[<i><a title=\"Wikipedia:Citation needed\" href=\"https:\/\/en.wikipedia.org\/wiki\/Wikipedia:Citation_needed\"><span title=\"This claim needs references to reliable sources. (October 2017)\">citation needed<\/span><\/a><\/i>]<\/sup><\/p>\n<p>Computing the\u00a0<a title=\"Inverse function\" href=\"https:\/\/en.wikipedia.org\/wiki\/Inverse_function\">inverse<\/a>\u00a0of the convolution operation is known as\u00a0<a title=\"Deconvolution\" href=\"https:\/\/en.wikipedia.org\/wiki\/Deconvolution\">deconvolution<\/a>.<\/p>\n<p>Source: <a href=\"https:\/\/en.wikipedia.org\/wiki\/Convolution\">https:\/\/en.wikipedia.org\/wiki\/Convolution<\/a><\/p>\n<p>Place an <a href=\"#anchor\">anchor<\/a><\/p>\n","protected":false},"author":940,"menu_order":2,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-105","chapter","type-chapter","status-web-only","hentry"],"part":103,"_links":{"self":[{"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/pressbooks\/v2\/chapters\/105","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/wp\/v2\/users\/940"}],"version-history":[{"count":4,"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/pressbooks\/v2\/chapters\/105\/revisions"}],"predecessor-version":[{"id":110,"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/pressbooks\/v2\/chapters\/105\/revisions\/110"}],"part":[{"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/pressbooks\/v2\/parts\/103"}],"metadata":[{"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/pressbooks\/v2\/chapters\/105\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/wp\/v2\/media?parent=105"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/pressbooks\/v2\/chapter-type?post=105"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/wp\/v2\/contributor?post=105"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/pressbooks.bccampus.ca\/hfriedman\/wp-json\/wp\/v2\/license?post=105"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}