{"id":282,"date":"2012-03-18T14:02:39","date_gmt":"2012-03-18T14:02:39","guid":{"rendered":"http:\/\/ahay.org\/blog\/?p=282"},"modified":"2015-09-04T03:50:09","modified_gmt":"2015-09-04T03:50:09","slug":"program-of-the-month-sfspectra","status":"publish","type":"post","link":"https:\/\/ahay.org\/blog\/2012\/03\/18\/program-of-the-month-sfspectra\/","title":{"rendered":"Program of the month: sfspectra"},"content":{"rendered":"<p><a href=\"\/RSF\/sfspectra.html\">sfspectra<\/a> computes spectrum, the absolute value of the 1-D Fourier transform along the fast axis. <\/p>\n<p>The following example from <a href=\"\/RSF\/book\/rsf\/su\/rsfkasper.html\">rsf\/su\/rsfkasper<\/a> shows a seismic shot gather before and after high-pass filtering and the corresponding spectra computed with <strong>sfspectra<\/strong>. <\/p>\n<p><img decoding=\"async\" src=\"\/RSF\/book\/rsf\/su\/rsfkasper\/Fig\/filt.png\" alt=\"\" title=\"\" \/> <img decoding=\"async\" src=\"\/RSF\/book\/rsf\/su\/rsfkasper\/Fig\/spec.png\" alt=\"\" title=\"\" \/><\/p>\n<p><strong>sfspectra<\/strong> has only one option: <strong>all=<\/strong>. If <strong>all=n<\/strong> (the default behavior), the spectrum is computed separately for each trace. If <strong>all=y<\/strong>, the output is the spectrum averaged across all traces. <\/p>\n<p>For a two-dimensional version, try <a href=\"\/RSF\/sfspectra2.html\">sfspectra2<\/a>. The following figures from <a href=\"\/RSF\/book\/jsg\/seislet\/lena.html\">jsg\/seislet\/lena<\/a> show the infamous <a href=\"http:\/\/en.wikipedia.org\/wiki\/Lenna\">Lena image<\/a> and the &#8220;seismic Lena&#8221; (after Chris Liner and <a href=\"http:\/\/dx.doi.org\/10.1190\/1.1481249\">David Monk<\/a>) <\/p>\n<p><img decoding=\"async\" src=\"\/RSF\/book\/jsg\/seislet\/lena\/Fig\/lena.png\" alt=\"\" title=\"\" \/> <img decoding=\"async\" src=\"\/RSF\/book\/jsg\/seislet\/lena\/Fig\/slena.png\" alt=\"\" title=\"\" \/><\/p>\n<p>and the corresponding 2-D spectra computed with <strong>sfspectra2<\/strong><\/p>\n<p><img decoding=\"async\" src=\"\/RSF\/book\/jsg\/seislet\/lena\/Fig\/flena.png\" alt=\"\" title=\"\" \/> <img decoding=\"async\" src=\"\/RSF\/book\/jsg\/seislet\/lena\/Fig\/fslena.png\" alt=\"\" title=\"\" \/><\/p>\n<h3 id=\"previousprogramsofthemonth\">Previous programs of the month<\/h3>\n<ul>\n<li><a href=\"\/blog\/2011\/07\/03\/program-of-the-month-sfnoise\/\">sfnoise<\/a><\/li>\n<li><a href=\"\/blog\/2011\/08\/09\/program-of-the-month-sfgraph\/\">sfgraph<\/a><\/li>\n<li><a href=\"\/blog\/2011\/09\/03\/program-of-the-month-sfclip\/\">sfclip<\/a><\/li>\n<li><a href=\"\/blog\/2011\/10\/01\/program-of-the-month-sfagc\/\">sfagc<\/a><\/li>\n<li><a href=\"\/blog\/2011\/11\/05\/program-of-the-month-sfenvelope\/\">sfenvelope<\/a><\/li>\n<li><a href=\"\/blog\/2011\/12\/03\/programs-of-the-month-sfcontour\/\">sfcontour<\/a><\/li>\n<li><a href=\"\/blog\/2012\/01\/01\/program-of-the-month-sfsmooth\/\">sfsmooth<\/a><\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>sfspectra computes spectrum, the absolute value of the 1-D Fourier transform along the fast axis. The following example from rsf\/su\/rsfkasper shows a seismic shot gather before and after high-pass filtering and the corresponding spectra computed with sfspectra. sfspectra has only one option: all=. If all=n (the default behavior), the spectrum is computed separately for each [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_import_markdown_pro_load_document_selector":0,"_import_markdown_pro_submit_text_textarea":"","activitypub_content_warning":"","activitypub_content_visibility":"local","activitypub_max_image_attachments":4,"activitypub_interaction_policy_quote":"","footnotes":""},"categories":[3],"tags":[],"class_list":["post-282","post","type-post","status-publish","format-standard","hentry","category-programs"],"_links":{"self":[{"href":"https:\/\/ahay.org\/blog\/wp-json\/wp\/v2\/posts\/282","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ahay.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ahay.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ahay.org\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ahay.org\/blog\/wp-json\/wp\/v2\/comments?post=282"}],"version-history":[{"count":3,"href":"https:\/\/ahay.org\/blog\/wp-json\/wp\/v2\/posts\/282\/revisions"}],"predecessor-version":[{"id":22338,"href":"https:\/\/ahay.org\/blog\/wp-json\/wp\/v2\/posts\/282\/revisions\/22338"}],"wp:attachment":[{"href":"https:\/\/ahay.org\/blog\/wp-json\/wp\/v2\/media?parent=282"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ahay.org\/blog\/wp-json\/wp\/v2\/categories?post=282"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ahay.org\/blog\/wp-json\/wp\/v2\/tags?post=282"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}