mirror of https://github.com/captn3m0/talks.git
194 lines
72 KiB
HTML
194 lines
72 KiB
HTML
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<!DOCTYPE html><html lang="en-US"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width,height=device-height,initial-scale=1.0"><meta name="apple-mobile-web-app-capable" content="yes"><meta http-equiv="X-UA-Compatible" content="ie=edge"><meta property="og:type" content="website"><meta name="twitter:card" content="summary"><style>.bespoke-marp-note,.bespoke-marp-osc,.bespoke-progress-parent{display:none;transition:none}@media screen{body[data-bespoke-view=""] .bespoke-marp-parent>.bespoke-marp-osc>button,body[data-bespoke-view=next] .bespoke-marp-parent>.bespoke-marp-osc>button,body[data-bespoke-view=presenter] .bespoke-marp-presenter-container .bespoke-marp-presenter-info-container button{-webkit-appearance:none;-moz-appearance:none;appearance:none;background-color:transparent;border:0;color:inherit;cursor:pointer;font-size:inherit;opacity:.8;outline:none;padding:0;transition:opacity .2s linear;-webkit-tap-highlight-color:transparent}body[data-bespoke-view=""] .bespoke-marp-parent>.bespoke-marp-osc>button:disabled,body[data-bespoke-view=next] .bespoke-marp-parent>.bespoke-marp-osc>button:disabled,body[data-bespoke-view=presenter] .bespoke-marp-presenter-container .bespoke-marp-presenter-info-container button:disabled{cursor:not-allowed;opacity:.15!important}body[data-bespoke-view=""] .bespoke-marp-parent>.bespoke-marp-osc>button:hover,body[data-bespoke-view=next] .bespoke-marp-parent>.bespoke-marp-osc>button:hover,body[data-bespoke-view=presenter] .bespoke-marp-presenter-container .bespoke-marp-presenter-info-container button:hover{opacity:1}body[data-bespoke-view=""] .bespoke-marp-parent>.bespoke-marp-osc>button:hover:active,body[data-bespoke-view=next] .bespoke-marp-parent>.bespoke-marp-osc>button:hover:active,body[data-bespoke-view=presenter] .bespoke-marp-presenter-container .bespoke-marp-presenter-info-container button:hover:active{opacity:.6}body[data-bespoke-view=""] .bespoke-marp-parent>.bespoke-marp-osc>button:hover:not(:disabled),body[data-bespoke-view=next] .bespoke-marp-parent>.bespoke-marp-osc>button:hover:not(:disabled),body[data-bespoke-view=presenter] .bespoke-marp-presenter-container .bespoke-marp-presenter-info-container button:hover:not(:disabled){transition:none}body[data-bespoke-view=""] .bespoke-marp-parent>.bespoke-marp-osc>button[data-bespoke-marp-osc=prev],body[data-bespoke-view=next] .bespoke-marp-parent>.bespoke-marp-osc>button[data-bespoke-marp-osc=prev],body[data-bespoke-view=presenter] .bespoke-marp-presenter-container .bespoke-marp-presenter-info-container button.bespoke-marp-presenter-info-page-prev{background:transparent url("data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHZpZXdCb3g9IjAgMCAxMDAgMTAwIj48cGF0aCBmaWxsPSJub25lIiBzdHJva2U9IiNmZmYiIHN0cm9rZS1saW5lY2FwPSJyb3VuZCIgc3Ryb2tlLWxpbmVqb2luPSJyb3VuZCIgc3Ryb2tlLXdpZHRoPSI1IiBkPSJNNjggOTBMMjggNTBsNDAtNDAiLz48L3N2Zz4=") no-repeat 50%;background-size:contain;overflow:hidden;text-indent:100%;white-space:nowrap}body[data-bespoke-view=""] .bespoke-marp-parent>.bespoke-marp-osc>button[data-bespoke-marp-osc=next],body[data-bespoke-view=next] .bespoke-marp-parent>.bespoke-marp-osc>button[data-bespoke-marp-osc=next],body[data-bespoke-view=presenter] .bespoke-marp-presenter-container .bespoke-marp-presenter-info-container button.bespoke-marp-presenter-info-page-next{background:transparent url("data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHZpZXdCb3g9IjAgMCAxMDAgMTAwIj48cGF0aCBmaWxsPSJub25lIiBzdHJva2U9IiNmZmYiIHN0cm9rZS1saW5lY2FwPSJyb3VuZCIgc3Ryb2tlLWxpbmVqb2luPSJyb3VuZCIgc3Ryb2tlLXdpZHRoPSI1IiBkPSJNMzIgOTBsNDAtNDAtNDAtNDAiLz48L3N2Zz4=") no-repeat 50%;background-size:contain;overflow:hidden;text-indent:100%;white-space:nowrap}body[data-bespoke-view=""] .bespoke-marp-parent>.bespoke-marp-osc>button[data-bespoke-marp-osc=fullscreen],body[data-bespoke-view=next] .bespoke-marp-parent>.bespoke-marp-osc>button[data-bespoke-marp-osc=fullscreen]{background:transparent url("data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHZpZXdCb3g9IjAgMC
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/*!
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* Marp default theme.
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*
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* @theme default
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* @author Yuki Hattori
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*
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* @auto-scaling true
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* @size 4:3 960px 720px
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*/div#p>svg>foreignObject>section .octicon{display:inline-block;fill:currentColor;vertical-align:text-bottom}div#p>svg>foreignObject>section .anchor{float:left;line-height:1;margin-left:-20px;padding-right:4px}div#p>svg>foreignObject>section .anchor:focus{outline:none}div#p>svg>foreignObject>section h1 .octicon-link,div#p>svg>foreignObject>section h2 .octicon-link,div#p>svg>foreignObject>section h3 .octicon-link,div#p>svg>foreignObject>section h4 .octicon-link,div#p>svg>foreignObject>section h5 .octicon-link,div#p>svg>foreignObject>section h6 .octicon-link{color:#1b1f23;vertical-align:middle;visibility:hidden}div#p>svg>foreignObject>section h1:hover .anchor,div#p>svg>foreignObject>section h2:hover .anchor,div#p>svg>foreignObject>section h3:hover .anchor,div#p>svg>foreignObject>section h4:hover .anchor,div#p>svg>foreignObject>section h5:hover .anchor,div#p>svg>foreignObject>section h6:hover .anchor{text-decoration:none}div#p>svg>foreignObject>section h1:hover .anchor .octicon-link,div#p>svg>foreignObject>section h2:hover .anchor .octicon-link,div#p>svg>foreignObject>section h3:hover .anchor .octicon-link,div#p>svg>foreignObject>section h4:hover .anchor .octicon-link,div#p>svg>foreignObject>section h5:hover .anchor .octicon-link,div#p>svg>foreignObject>section h6:hover .anchor .octicon-link{visibility:visible}div#p>svg>foreignObject>section h1:hover .anchor .octicon-link:before,div#p>svg>foreignObject>section h2:hover .anchor .octicon-link:before,div#p>svg>foreignObject>section h3:hover .anchor .octicon-link:before,div#p>svg>foreignObject>section h4:hover .anchor .octicon-link:before,div#p>svg>foreignObject>section h5:hover .anchor .octicon-link:before,div#p>svg>foreignObject>section h6:hover .anchor .octicon-link:before{width:16px;height:16px;content:" ";display:inline-block;background-image:url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' aria-hidden='true'%3E%3Cpath fill-rule='evenodd' d='M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z'/%3E%3C/svg%3E")}div#p>svg>foreignObject>section{-ms-text-size-adjust:100%;-webkit-text-size-adjust:100%;color:#24292e;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Helvetica,Arial,sans-serif,Apple Color Emoji,Segoe UI Emoji;font-size:16px;line-height:1.5;word-wrap:break-word}div#p>svg>foreignObject>section details{display:block}div#p>svg>foreignObject>section summary{display:list-item}div#p>svg>foreignObject>section a{background-color:initial}div#p>svg>foreignObject>section a:active,div#p>svg>foreignObject>section a:hover{outline-width:0}div#p>svg>foreignObject>section strong{font-weight:inherit;font-weight:bolder}div#p>svg>foreignObject>section h1{margin:.67em 0}div#p>svg>foreignObject>section img{border-style:none}div#p>svg>foreignObject>section code,div#p>svg>foreignObject>section kbd,div#p>svg>foreignObject>section pre{font-family:monospace,monospace;font-size:1em}div#p>svg>foreignObject>section hr{box-sizing:initial;overflow:visible}div#p>svg>foreignObject>section input{font:inherit;margin:0;overflow:visible}div#p>svg>foreignObject>section [type=checkbox]{padding:0}div#p>svg>foreignObject>section *,div#p>svg>foreignObject>section [type=checkbox]{box-sizing:border-box}div#p>svg>foreignObject>section input{font-family:inherit;font-size:inherit;line-height:inherit}div#p>svg>foreignObject>section a{color:#0366d6;text-decoration:none}div#p>svg>foreignObject>section a:hover{text-decoration:underline}div#p>svg>foreignObject>section strong{font-weight:600}div#p>svg>foreignObject>section hr{height:0;margin:15px 0;overflow:hidden;background:transparent;border-bottom:1px solid #dfe2e5}div#p>svg>foreignObject>section hr:after,div#p>svg>foreignObject>section hr:before{display:table;content:""}div#p>svg>foreignObject>section hr:after{clear:both}div#p>sv
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/* content:""; */}div#p>svg>foreignObject>section:after{clear:both}div#p>svg>foreignObject>section>:first-child{margin-top:0!important}div#p>svg>foreignObject>section>:last-child{margin-bottom:0!important}div#p>svg>foreignObject>section a:not([href]){color:inherit;text-decoration:none}div#p>svg>foreignObject>section blockquote,div#p>svg>foreignObject>section details,div#p>svg>foreignObject>section dl,div#p>svg>foreignObject>section ol,div#p>svg>foreignObject>section p,div#p>svg>foreignObject>section pre,div#p>svg>foreignObject>section table,div#p>svg>foreignObject>section ul{margin-top:0;margin-bottom:16px}div#p>svg>foreignObject>section hr{height:.25em;padding:0;margin:24px 0;background-color:#e1e4e8;border:0}div#p>svg>foreignObject>section blockquote{padding:0 1em;color:#6a737d;border-left:.25em solid #dfe2e5}div#p>svg>foreignObject>section blockquote>:first-child{margin-top:0}div#p>svg>foreignObject>section blockquote>:last-child{margin-bottom:0}div#p>svg>foreignObject>section h1,div#p>svg>foreignObject>section h2,div#p>svg>foreignObject>section h3,div#p>svg>foreignObject>section h4,div#p>svg>foreignObject>section h5,div#p>svg>foreignObject>section h6{margin-top:24px;margin-bottom:16px;font-weight:600;line-height:1.25}div#p>svg>foreignObject>section h1{font-size:2em}div#p>svg>foreignObject>section h1,div#p>svg>foreignObject>section h2{padding-bottom:.3em;border-bottom:1px solid #eaecef}div#p>svg>foreignObject>section h2{font-size:1.5em}div#p>svg>foreignObject>section h3{font-size:1.25em}div#p>svg>foreignObject>section h4{font-size:1em}div#p>svg>foreignObject>section h5{font-size:.875em}div#p>svg>foreignObject>section h6{font-size:.85em;color:#6a737d}div#p>svg>foreignObject>section ol,div#p>svg>foreignObject>section ul{padding-left:2em}div#p>svg>foreignObject>section ol ol,div#p>svg>foreignObject>section ol ul,div#p>svg>foreignObject>section ul ol,div#p>svg>foreignObject>section ul ul{margin-top:0;margin-bottom:0}div#p>svg>foreignObject>section li{word-wrap:break-all}div#p>svg>foreignObject>section li>p{margin-top:16px}div#p>svg>foreignObject>section li+li{margin-top:.25em}div#p>svg>foreignObject>section dl{padding:0}div#p>svg>foreignObject>section dl dt{padding:0;margin-top:16px;font-size:1em;font-style:italic;font-weight:600}div#p>svg>foreignObject>section dl dd{padding:0 16px;margin-bottom:16px}div#p>svg>foreignObject>section table{display:block;width:100%;overflow:auto}div#p>svg>foreignObject>section table th{font-weight:600}div#p>svg>foreignObject>section table td,div#p>svg>foreignObject>section table th{padding:6px 13px;border:1px solid #dfe2e5}div#p>svg>foreignObject>section table tr{background-color:#fff;border-top:1px solid #c6cbd1}div#p>svg>foreignObject>section table tr:nth-child(2n){background-color:#f6f8fa}div#p>svg>foreignObject>section img{max-width:100%;box-sizing:initial;background-color:#fff}div#p>svg>foreignObject>section img[align=right]{padding-left:20px}div#p>svg>foreignObject>section img[align=left]{padding-right:20px}div#p>svg>foreignObject>section code{padding:.2em .4em;margin:0;font-size:85%;background-color:rgba(27,31,35,.05);border-radius:3px}div#p>svg>foreignObject>section pre{word-wrap:normal}div#p>svg>foreignObject>section pre>code{padding:0;margin:0;font-size:100%;word-break:normal;white-space:pre;background:transparent;border:0}div#p>svg>foreignObject>section .highlight{margin-bottom:16px}div#p>svg>foreignObject>section .highlight pre{margin-bottom:0;word-break:normal}div#p>svg>foreignObject>section pre{padding:16px;overflow:auto;font-size:85%;line-height:1.45;background-color:#f6f8fa;border-radius:3px}div#p>svg>foreignObject>section pre code{display:inline;max-width:auto;padding:0;margin:0;overflow:visible;line-height:inherit;word-wrap:normal;background-color:initial;border:0}div#p>svg>foreignObject>section .commit-tease-sha{display:inline-block;font-family:SFMono-Regular,Consolas,Liberation Mono,Menlo,monospace;font-size:90%;color:#444d56}div#p>svg>foreignObject>section .full-commit .btn-outline:not(:disabled):hover{color:#005cc5;border-color:#005cc5}div#p>svg>foreignObject>section
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<h1>everything i learned about streaming video in linux</h1>
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<p>-nemo</p>
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</section>
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</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="2">
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<h1>demo</h1>
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</section>
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</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="3">
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<h1>let's talk about X11</h1>
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<pre><code><svg data-marp-fitting="svg" data-marp-fitting-code><foreignObject><span data-marp-fitting-svg-content><span data-marp-fitting-svg-content-wrap>+-------------------------+
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|<span class="hljs-string"> input devices </span>|
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|<span class="hljs-string"> keyboard </span>|<span class="hljs-string"> mouse </span>|
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+-------^---+-^-----------+
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|<span class="hljs-string"> </span>|
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|<span class="hljs-string"> </span>|<span class="hljs-string"> +------------------------+
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+-v-----v-------+-------->+ </span>|
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|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|
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|<span class="hljs-string"> X Server +-------->+ </span>|
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|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|
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+--+---------+--+-------->+ Screen |<span class="hljs-string">
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^ ^ </span>|<span class="hljs-string"> </span>|
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|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|
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|<span class="hljs-string"> </span>|<span class="hljs-string"> +------------------------+
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v v
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+-------+---+ +--+-------+
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</span>|<span class="hljs-string"> browser </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|
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|<span class="hljs-string"> X client </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> xterm </span>|
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|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|
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+-----------+ +----------+
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</span></span></foreignObject></svg></code></pre>
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</section>
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</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="4">
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<h1>x11 - displays and screens</h1>
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<ul>
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<li>
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<p>You "select" a display with the <code>:$DISPLAY:SCREEN</code> syntax.</p>
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</li>
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<li>
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<p>So the first screen on your main display server would be :0.0</p>
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</li>
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<li>
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<p>You can set the display an application launches with DISPLAY environment variable</p>
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</li>
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</ul>
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<p><code>export DISPLAY=:0.1 leafpad</code></p>
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</section>
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</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="5">
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<h1>Xvfb</h1>
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<blockquote>
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<p>Xvfb or X virtual framebuffer is a display server implementing the X11 display server protocol. In contrast to other display servers, Xvfb performs all graphical operations in virtual memory without showing any screen output.</p>
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</blockquote>
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<blockquote>
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<p>However, no output is shown. This virtual server does not require the computer it is running on to have any kind of graphics adapter, a screen or any input device.</p>
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</blockquote>
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</section>
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</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="6">
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<h1><code>xwd</code></h1>
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<blockquote>
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<p>xwd - dump an image of an X window</p>
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</blockquote>
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<pre><code><svg data-marp-fitting="svg" data-marp-fitting-code><foreignObject><span data-marp-fitting-svg-content><span data-marp-fitting-svg-content-wrap>xwd -root <span class="hljs-built_in">image</span>.xwd
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<span class="hljs-built_in">convert</span> <span class="hljs-built_in">image</span>.xwd <span class="hljs-built_in">image</span>.png
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</span></span></foreignObject></svg></code></pre>
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</section>
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</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="7">
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<h1><code>ffmpeg</code></h1>
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<p>can "grab" X11 windows</p>
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<pre><code><svg data-marp-fitting="svg" data-marp-fitting-code><foreignObject><span data-marp-fitting-svg-content><span data-marp-fitting-svg-content-wrap>ffmpeg -f x11grab -framerate <span class="hljs-number">10</span> -<span class="hljs-string">i :</span><span class="hljs-number">1.0</span> \
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-vaapi_device <span class="hljs-regexp">/dev/</span>dri/renderD128 \
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-vf <span class="hljs-string">'format=nv12,hwupload,scale_vaapi=w=854:h=480'</span> \
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-<span class="hljs-string">c:</span>v h264_vaapi -<span class="hljs-string">qp:</span>v <span class="hljs-number">26</span> -bf <span class="hljs-number">0</span> -tune zerolatency -f mpegts \
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<span class="hljs-symbol"> udp:</span><span class="hljs-comment">//localhost:12345</span>
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</span></span></foreignObject></svg></code></pre>
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</section>
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</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="8">
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<h1>video devices</h1>
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<ul>
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<li><code>/dev/video*</code></li>
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</ul>
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<pre><code><svg data-marp-fitting="svg" data-marp-fitting-code><foreignObject><span data-marp-fitting-svg-content><span data-marp-fitting-svg-content-wrap><span class="hljs-meta">v4l2-ctl</span> <span class="hljs-string">--device /dev/video2 --all</span>
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<span class="hljs-attr">Driver</span> <span class="hljs-string">Info:</span>
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<span class="hljs-attr">Driver</span> <span class="hljs-string">name : uvcvideo</span>
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<span class="hljs-attr">Card</span> <span class="hljs-string">type : HD Pro Webcam C920</span>
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<span class="hljs-attr">Bus</span> <span class="hljs-string">info : usb-0000:00:14.0-4</span>
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<span class="hljs-attr">Driver</span> <span class="hljs-string">version : 5.7.9</span>
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<span class="hljs-attr">Capabilities</span> : <span class="hljs-string">0x84a00001</span>
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<span class="hljs-attr">Video</span> <span class="hljs-string">Capture</span>
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<span class="hljs-attr">Metadata</span> <span class="hljs-string">Capture</span>
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<span class="hljs-attr">Streaming</span>
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<span class="hljs-attr">Extended</span> <span class="hljs-string">Pix Format</span>
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<span class="hljs-attr">Device</span> <span class="hljs-string">Capabilities</span>
|
||
|
|
<span class="hljs-attr">Device</span> <span class="hljs-string">Caps : 0x04a00000</span>
|
||
|
|
<span class="hljs-attr">Metadata</span> <span class="hljs-string">Capture</span>
|
||
|
|
<span class="hljs-attr">Streaming</span>
|
||
|
|
<span class="hljs-attr">Extended</span> <span class="hljs-string">Pix Format</span>
|
||
|
|
<span class="hljs-attr">Priority</span>: <span class="hljs-string">2</span>
|
||
|
|
<span class="hljs-attr">Format</span> <span class="hljs-string">Metadata Capture:</span>
|
||
|
|
<span class="hljs-attr">Sample</span> <span class="hljs-string">Format : 'UVCH' (UVC Payload Header Metadata)</span>
|
||
|
|
<span class="hljs-attr">Buffer</span> <span class="hljs-string">Size : 1024</span>
|
||
|
|
</span></span></foreignObject></svg></code></pre>
|
||
|
|
</section>
|
||
|
|
</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="9">
|
||
|
|
<h1>v4l2loopback</h1>
|
||
|
|
<blockquote>
|
||
|
|
<p>v4l2loopback - a kernel module to create V4L2 loopback devices</p>
|
||
|
|
</blockquote>
|
||
|
|
<blockquote>
|
||
|
|
<p>this module allows you to create "virtual video devices" normal (v4l2) applications will read these devices as if they were ordinary video devices, but the video will not be read from e.g. a capture card but instead it is generated by another application. this allows you for instance to apply some nifty video effects on your Skype video... it also allows some more serious things (e.g. I've been using it to add streaming capabilities to an application by the means of hooking GStreamer into the loopback devices).</p>
|
||
|
|
</blockquote>
|
||
|
|
</section>
|
||
|
|
</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="10">
|
||
|
|
<h1>create new webcams!</h1>
|
||
|
|
<pre><code><svg data-marp-fitting="svg" data-marp-fitting-code><foreignObject><span data-marp-fitting-svg-content><span data-marp-fitting-svg-content-wrap>modprobe v4l2loopback <span class="hljs-attribute">devices</span>=4
|
||
|
|
</span></span></foreignObject></svg></code></pre>
|
||
|
|
<p><code>/dev/video3,4,5,6,7</code></p>
|
||
|
|
</section>
|
||
|
|
</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="11">
|
||
|
|
<h1>ffmpeg can "write" to v4l</h1>
|
||
|
|
<pre><code><svg data-marp-fitting="svg" data-marp-fitting-code><foreignObject><span data-marp-fitting-svg-content><span data-marp-fitting-svg-content-wrap><span class="hljs-attr">ffmpeg</span> <span class="hljs-string">-f x11grab \
|
||
|
|
-framerate 4 \
|
||
|
|
-s 854x480 \
|
||
|
|
-i :1.0 \
|
||
|
|
-pix_fmt yuv420p \
|
||
|
|
-f v4l2 /dev/video3</span>
|
||
|
|
</span></span></foreignObject></svg></code></pre>
|
||
|
|
<p><code>ffmpeg -pix_fmts</code></p>
|
||
|
|
</section>
|
||
|
|
</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="12">
|
||
|
|
<h1>aside: MJPEG over HTTP</h1>
|
||
|
|
<p><code>ffmpeg -i ... -f mjpg -o file.jpg</code></p>
|
||
|
|
<pre><code><svg data-marp-fitting="svg" data-marp-fitting-code><foreignObject><span data-marp-fitting-svg-content><span data-marp-fitting-svg-content-wrap><span class="hljs-attribute">Content-Type</span>: multipart/x-mixed-replace; boundary="JPGBoundary"
|
||
|
|
|
||
|
|
<span class="livecodeserver"><span class="hljs-comment">--JPGBoundary</span>
|
||
|
|
Content-Type: image/jpeg
|
||
|
|
|
||
|
|
<jpeg <span class="hljs-keyword">bytes</span>>
|
||
|
|
<span class="hljs-comment">--JPGBoundary</span>
|
||
|
|
Content-Type: image/jpeg
|
||
|
|
|
||
|
|
<jpeg <span class="hljs-keyword">bytes</span>>
|
||
|
|
<span class="hljs-comment">--JPGBoundary</span>
|
||
|
|
... <span class="hljs-keyword">and</span> so <span class="hljs-keyword">on</span> ...
|
||
|
|
<span class="hljs-comment">--JPGBoundary--</span>
|
||
|
|
</span></span></span></foreignObject></svg></code></pre>
|
||
|
|
</section>
|
||
|
|
</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="13">
|
||
|
|
<h1>MJPEG streaming is simple</h1>
|
||
|
|
<ul>
|
||
|
|
<li><code>mjpeg-server</code> (uses <code>ffmpeg -f mjpg</code>)</li>
|
||
|
|
<li><code>ustreamer</code> (only supports <code>/dev/video*</code>)</li>
|
||
|
|
</ul>
|
||
|
|
</section>
|
||
|
|
</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="14">
|
||
|
|
<pre><code><svg data-marp-fitting="svg" data-marp-fitting-code><foreignObject><span data-marp-fitting-svg-content><span data-marp-fitting-svg-content-wrap>+---------------------+ +---------------------------+
|
||
|
|
|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|
|
||
|
|
|<span class="hljs-string"> Xvfb Virtual +------> </span>|<span class="hljs-string"> ffmpeg -f x11grab </span>|
|
||
|
|
+---------+-----------+ |<span class="hljs-string"> -o /de^/video3 </span>|
|
||
|
|
^ +---------------------------+
|
||
|
|
+------+----------+ |<span class="hljs-string">
|
||
|
|
</span>|<span class="hljs-string"> X Server +<---+ +---------+-----------+
|
||
|
|
+---+-------------+ </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> /dev/video3 </span>|
|
||
|
|
^ |<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|<span class="hljs-string">-???->USTREAMER->Viewers ???
|
||
|
|
+---+---+ </span>|<span class="hljs-string"> +-------+-------------+
|
||
|
|
</span>|<span class="hljs-string"> baba </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|
|
||
|
|
|<span class="hljs-string"> is </span>|<span class="hljs-string"> +-----+---------+ </span>|<span class="hljs-string"> +-----------+
|
||
|
|
</span>|<span class="hljs-string"> you </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> +-->+ Zoom </span>|
|
||
|
|
|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> xdotool </span>|<span class="hljs-string"> </span>|<span class="hljs-string"> </span>|
|
||
|
|
+-------+ +---------------+ +-----------+
|
||
|
|
</span></span></foreignObject></svg></code></pre>
|
||
|
|
</section>
|
||
|
|
</foreignObject></svg><svg data-marpit-svg="" viewBox="0 0 1280 720"><foreignObject width="1280" height="720"><section id="15">
|
||
|
|
<h1>security</h1>
|
||
|
|
<p>YOLO!</p>
|
||
|
|
<p>Pitch: RFCs We Love!</p>
|
||
|
|
</section>
|
||
|
|
<script>!function(){"use strict";function t(t){Array.from(document.getElementsByTagName("svg"),e=>{if(e.hasAttribute("data-marpit-svg")){const{clientHeight:r,clientWidth:a}=e;e.style.transform||(e.style.transform="translateZ(0)");const o=t||e.currentScale||1,i=e.viewBox.baseVal.width/o,n=e.viewBox.baseVal.height/o,s=Math.min(r/n,a/i);Array.from(e.querySelectorAll(":scope > foreignObject"),t=>{const e=t.x.baseVal.value,o=t.y.baseVal.value;Array.from(t.querySelectorAll(":scope > section"),t=>{t.style.transformOrigin||(t.style.transformOrigin="0 0");const l=(a-s*i)/2-e,c=(r-s*n)/2-o;t.style.transform=`translate3d(${l}px,${c}px,0) scale(${s}) translate(${e}px,${o}px)`})})}})}const e=(t,e,r)=>{if(t.getAttribute(e)!==r)return t.setAttribute(e,r),!0};function r(a=!0){for(const e of"Apple Computer, Inc."===navigator.vendor?[t]:[])e();Array.from(document.querySelectorAll('svg[data-marp-fitting="svg"]'),t=>{const r=t.firstChild,a=r.firstChild,{scrollWidth:o,scrollHeight:i}=a;let n,s=1;if(t.hasAttribute("data-marp-fitting-code")&&(n=t.parentElement.parentElement),t.hasAttribute("data-marp-fitting-math")&&(n=t.parentElement),n){const t=getComputedStyle(n),e=Math.ceil(n.clientWidth-parseFloat(t.paddingLeft)-parseFloat(t.paddingRight));e&&(s=e)}const l=Math.max(o,s),c=Math.max(i,1),p=`0 0 ${l} ${c}`;e(r,"width",""+l),e(r,"height",""+c),e(t,"preserveAspectRatio",getComputedStyle(t).getPropertyValue("--preserve-aspect-ratio")||"xMinYMin meet"),e(t,"viewBox",p)&&t.classList.toggle("__reflow__")}),a&&window.requestAnimationFrame(()=>r(a))}!function(){if("undefined"==typeof window)throw new Error("Marp Core's browser script is valid only in browser context.");window.marpCoreBrowserScript?console.warn("Marp Core's browser script has already executed."):(Object.defineProperty(window,"marpCoreBrowserScript",{value:!0}),r())}()}();
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||
|
|
</script></foreignObject></svg></div><script>!function(){"use strict";var e=function(e,t){var n,r=1===(e.parent||e).nodeType?e.parent||e:document.querySelector(e.parent||e),s=[].filter.call("string"==typeof e.slides?r.querySelectorAll(e.slides):e.slides||r.children,(function(e){return"SCRIPT"!==e.nodeName})),a={},o=function(e,t){return(t=t||{}).index=s.indexOf(e),t.slide=e,t},i=function(e,t){a[e]=(a[e]||[]).filter((function(e){return e!==t}))},l=function(e,t){return(a[e]||[]).reduce((function(e,n){return e&&!1!==n(t)}),!0)},c=function(e,t){s[e]&&(n&&l("deactivate",o(n,t)),n=s[e],l("activate",o(n,t)))},d=function(e,t){var r=s.indexOf(n)+e;l(e>0?"next":"prev",o(n,t))&&c(r,t)},u={off:i,on:function(e,t){return(a[e]||(a[e]=[])).push(t),i.bind(null,e,t)},fire:l,slide:function(e,t){if(!arguments.length)return s.indexOf(n);l("slide",o(s[e],t))&&c(e,t)},next:d.bind(null,1),prev:d.bind(null,-1),parent:r,slides:s,destroy:function(e){l("destroy",o(n,e)),a={}}};return(t||[]).forEach((function(e){e(u)})),n||c(0),u};function t(e){e.parent.classList.add("bespoke-marp-parent"),e.slides.map(e=>e.classList.add("bespoke-marp-slide")),e.on("activate",t=>{e.slides.map(e=>e.classList.remove("bespoke-marp-active")),t.slide.classList.add("bespoke-marp-active")})}function n(e=2e3){return t=>{let n;function r(){n&&clearTimeout(n),n=setTimeout(()=>{t.parent.classList.add("bespoke-marp-inactive")},e),t.parent.classList.remove("bespoke-marp-inactive")}document.addEventListener("mousedown",r),document.addEventListener("mousemove",r),document.addEventListener("touchend",r),setTimeout(r,0)}}const r=["AUDIO","BUTTON","INPUT","SELECT","TEXTAREA","VIDEO"];function s(e){e.parent.addEventListener("keydown",e=>{if(!e.target)return;const t=e.target;(r.includes(t.nodeName)||"true"===t.contentEditable)&&e.stopPropagation()})}function a(e){window.addEventListener("load",()=>{for(const t of e.slides){const e=t.querySelector("[data-marp-fitting]")?"":"hideable";t.setAttribute("data-bespoke-marp-load",e)}})}function o(e){let t=0,n=0;Object.defineProperty(e,"fragments",{enumerable:!0,value:e.slides.map(e=>[null,...e.querySelectorAll("[data-marpit-fragment]")])});const r=r=>void 0!==e.fragments[t][n+r],s=(r,s)=>{t=r,n=s,e.fragments.forEach((e,t)=>{e.forEach((e,n)=>{if(null==e)return;const a=t<r||t===r&&n<=s;e.setAttribute("data-bespoke-marp-fragment",a?"active":"inactive"),t===r&&n===s?e.setAttribute("data-bespoke-marp-current-fragment","current"):e.removeAttribute("data-bespoke-marp-current-fragment")})}),e.fragmentIndex=s;const a={slide:e.slides[r],index:r,fragments:e.fragments[r],fragmentIndex:s};e.fire("fragment",a)};e.on("next",()=>{if(r(1))return s(t,n+1),!1;const a=t+1;e.fragments[a]&&s(a,0)}),e.on("prev",()=>{if(r(-1))return s(t,n-1),!1;const a=t-1;e.fragments[a]&&s(a,e.fragments[a].length-1)}),e.on("slide",({index:t,fragment:n})=>{let r=0;if(void 0!==n){const s=e.fragments[t];if(s){const{length:e}=s;r=-1===n?e-1:Math.min(Math.max(n,0),e-1)}}s(t,r)}),s(0,0)}var i,l=function(e,t){return e(t={exports:{}},t.exports),t.exports}((function(e){
|
||
|
|
/*!
|
||
|
|
* screenfull
|
||
|
|
* v5.0.2 - 2020-02-13
|
||
|
|
* (c) Sindre Sorhus; MIT License
|
||
|
|
*/
|
||
|
|
!function(){var t="undefined"!=typeof window&&void 0!==window.document?window.document:{},n=e.exports,r=function(){for(var e,n=[["requestFullscreen","exitFullscreen","fullscreenElement","fullscreenEnabled","fullscreenchange","fullscreenerror"],["webkitRequestFullscreen","webkitExitFullscreen","webkitFullscreenElement","webkitFullscreenEnabled","webkitfullscreenchange","webkitfullscreenerror"],["webkitRequestFullScreen","webkitCancelFullScreen","webkitCurrentFullScreenElement","webkitCancelFullScreen","webkitfullscreenchange","webkitfullscreenerror"],["mozRequestFullScreen","mozCancelFullScreen","mozFullScreenElement","mozFullScreenEnabled","mozfullscreenchange","mozfullscreenerror"],["msRequestFullscreen","msExitFullscreen","msFullscreenElement","msFullscreenEnabled","MSFullscreenChange","MSFullscreenError"]],r=0,s=n.length,a={};r<s;r++)if((e=n[r])&&e[1]in t){for(r=0;r<e.length;r++)a[n[0][r]]=e[r];return a}return!1}(),s={change:r.fullscreenchange,error:r.fullscreenerror},a={request:function(e){return new Promise(function(n,s){var a=function(){this.off("change",a),n()}.bind(this);this.on("change",a);var o=(e=e||t.documentElement)[r.requestFullscreen]();o instanceof Promise&&o.then(a).catch(s)}.bind(this))},exit:function(){return new Promise(function(e,n){if(this.isFullscreen){var s=function(){this.off("change",s),e()}.bind(this);this.on("change",s);var a=t[r.exitFullscreen]();a instanceof Promise&&a.then(s).catch(n)}else e()}.bind(this))},toggle:function(e){return this.isFullscreen?this.exit():this.request(e)},onchange:function(e){this.on("change",e)},onerror:function(e){this.on("error",e)},on:function(e,n){var r=s[e];r&&t.addEventListener(r,n,!1)},off:function(e,n){var r=s[e];r&&t.removeEventListener(r,n,!1)},raw:r};r?(Object.defineProperties(a,{isFullscreen:{get:function(){return Boolean(t[r.fullscreenElement])}},element:{enumerable:!0,get:function(){return t[r.fullscreenElement]}},isEnabled:{enumerable:!0,get:function(){return Boolean(t[r.fullscreenEnabled])}}}),n?e.exports=a:window.screenfull=a):n?e.exports={isEnabled:!1}:window.screenfull={isEnabled:!1}}()}));l.isEnabled;function c(e){e.fullscreen=()=>{l.isEnabled&&l.toggle(document.body)},document.addEventListener("keydown",t=>{70!==t.which&&122!==t.which||t.altKey||t.ctrlKey||t.metaKey||!l.isEnabled||(e.fullscreen(),t.preventDefault())})}function d(e={}){const t=Object.assign({interval:200},e);return e=>{document.addEventListener("keydown",t=>{(32===t.which&&t.shiftKey||33===t.which||37===t.which||38===t.which)&&e.prev(),(32===t.which&&!t.shiftKey||34===t.which||39===t.which||40===t.which)&&e.next(),35===t.which&&e.slide(e.slides.length-1,{fragment:-1}),36===t.which&&e.slide(0)});let n,r,s=0;e.parent.addEventListener("wheel",a=>{let o=!1;const l=(e,t)=>{e&&(o=o||function(e,t){return function(e,t){const n=t===i.X?"Width":"Height";return e["client"+n]<e["scroll"+n]}(e,t)&&function(e,t){const{overflow:n}=e,r=e["overflow"+t];return"auto"===n||"scroll"===n||"auto"===r||"scroll"===r}(getComputedStyle(e),t)}(e,t)),(null==e?void 0:e.parentElement)&&l(e.parentElement,t)};if(0!==a.deltaX&&l(a.target,i.X),0!==a.deltaY&&l(a.target,i.Y),o)return;a.preventDefault(),r&&clearTimeout(r),r=setTimeout(()=>{n=0},t.interval);const c=Date.now()-s<t.interval,d=Math.sqrt(Math.pow(a.deltaX,2)+Math.pow(a.deltaY,2)),u=d<=n;if(n=d,c||u)return;let f;(a.deltaX>0||a.deltaY>0)&&(f="next"),(a.deltaX<0||a.deltaY<0)&&(f="prev"),f&&(e[f](),s=Date.now())})}}!function(e){e.X="X",e.Y="Y"}(i||(i={}));const u=(...e)=>history.replaceState(...e);var f;!function(e){e.Normal="",e.Presenter="presenter",e.Next="next"}(f||(f={}));const p=(e,{protocol:t,host:n,pathname:r,hash:s}=location)=>{const a=e.toString();return`${t}//${n}${r}${a?"?":""}${a}${s}`},m=()=>{switch(document.body.getAttribute("data-bespoke-view")){case f.Normal:return f.Normal;case f.Presenter:return f.Presenter;case f.Next:return f.Next;default:throw new Error("View mode is not assigned.")}},h=e=>new URLSearchParams(location.search).get(e),g=(e,t={})=>{const n=Object.assign({location:location,setter:u},t),r=new URLSearchParams(n.location.searc
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||
|
|
</script></body></html>
|