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searchaux" style="display:none">JPEG encoder</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">For the eponymous baked goods, see <a href="/wiki/Biscuit" title="Biscuit">Biscuit</a>.</div> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox vevent"><caption class="infobox-title summary">Guetzli</caption><tbody><tr><td colspan="2" class="infobox-image logo"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Guetzli_logo.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/d2/Guetzli_logo.svg/220px-Guetzli_logo.svg.png" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/d2/Guetzli_logo.svg/330px-Guetzli_logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/d2/Guetzli_logo.svg/440px-Guetzli_logo.svg.png 2x" data-file-width="512" data-file-height="512" /></a></span></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Programmer" title="Programmer">Original author(s)</a></th><td class="infobox-data">Google Research</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Initial release</th><td class="infobox-data">March 15, 2017<span class="noprint">; 7 years ago</span><span style="display:none"> (<span class="bday dtstart published updated">2017-03-15</span>)</span></td></tr><tr style="display: none;"><td colspan="2" class="infobox-full-data"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1257001546"></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Software_release_life_cycle" title="Software release life cycle">Stable release</a></th><td class="infobox-data"><div style="margin:0px;">1.0.1 / March 21, 2017<span class="noprint">; 7 years ago</span><span style="display:none"> (<span class="bday dtstart published updated">2017-03-21</span>)</span></div></td></tr><tr style="display:none"><td colspan="2"> </td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Repository_(version_control)" title="Repository (version control)">Repository</a></th><td class="infobox-data"><span class="url"><a rel="nofollow" class="external text" href="https://github.com/google/guetzli">github<wbr />.com<wbr />/google<wbr />/guetzli</a></span></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Written in</th><td class="infobox-data"><a href="/wiki/C%2B%2B" title="C++">C++</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Technical_standard" title="Technical standard">Standard</a>(s)</th><td class="infobox-data"><a href="/wiki/JPEG" title="JPEG">JPEG</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Software_license" title="Software license">License</a></th><td class="infobox-data"><a href="/wiki/Apache_License_2.0" class="mw-redirect" title="Apache License 2.0">Apache License 2.0</a></td></tr></tbody></table> <p><b>Guetzli</b> is a freely licensed <a href="/wiki/JPEG" title="JPEG">JPEG</a> encoder that Jyrki Alakuijala, Robert Obryk, and <a href="/wiki/Zolt%C3%A1n_Szabadka" class="mw-redirect" title="Zoltán Szabadka">Zoltán Szabadka</a> have developed in <a href="/wiki/Google" title="Google">Google</a>'s <a href="/wiki/Z%C3%BCrich" class="mw-redirect" title="Zürich">Zürich</a> research branch. The encoder seeks to produce significantly smaller files than prior encoders at equivalent quality, albeit at very low speed. It is named after the <a href="/wiki/Swiss_German" title="Swiss German">Swiss German</a> <a href="/wiki/Diminutive" title="Diminutive">diminutive</a> expression for <a href="/wiki/Biscuit" title="Biscuit">biscuits</a>,<sup id="cite_ref-arstechnica20170317_1-0" class="reference"><a href="#cite_note-arstechnica20170317-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> in line with the names of other compression technology from Google.<sup id="cite_ref-watson.ch_2-0" class="reference"><a href="#cite_note-watson.ch-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-names_3-0" class="reference"><a href="#cite_note-names-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Operation">Operation</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Guetzli&action=edit&section=1" title="Edit section: Operation"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Guetzli optimizes the <a href="/wiki/Quantization_(image_processing)" title="Quantization (image processing)">quantization</a> step of encoding to achieve compression efficiency. It constructs custom quantization tables for each file, decides on <a href="/wiki/Color_subsampling" class="mw-redirect" title="Color subsampling">color subsampling</a>,<sup id="cite_ref-INpact_4-0" class="reference"><a href="#cite_note-INpact-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> and quantizes adjacent <a href="/wiki/Discrete_cosine_transform" title="Discrete cosine transform">DCT</a> coefficients to zero, balancing benefits in the <a href="/wiki/Run-length_encoding" title="Run-length encoding">run-length encoding</a> of coefficients and preservation of perceived image fidelity. Zeroing the right coefficients is the most effective tool in Guetzli, which is used as a makeshift means of spatially adaptive quantization. Guetzli uses Butteraugli (another open-source Google project) to guide compression.<sup id="cite_ref-SimAnneal_5-0" class="reference"><a href="#cite_note-SimAnneal-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>Guetzli is resource-intensive, requiring orders of magnitude more processing time and <a href="/wiki/Random-access_memory" title="Random-access memory">random-access memory</a> than other JPEG encoders.<sup id="cite_ref-chip.de_6-0" class="reference"><a href="#cite_note-chip.de-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Guetzli supports only the top of JPEG's quality range (quantizer settings 84–100)<sup id="cite_ref-davidwalsh.name_7-0" class="reference"><a href="#cite_note-davidwalsh.name-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-images.guide_8-0" class="reference"><a href="#cite_note-images.guide-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> and supports only sequential (non-"progressive") encoding. Guetzli is more effective with bigger files.<sup id="cite_ref-images.guide_8-1" class="reference"><a href="#cite_note-images.guide-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> Google says it is a demonstration of the potential of psychovisual optimizations, intended to motivate further research into future JPEG encoders.<sup id="cite_ref-watson.ch_2-1" class="reference"><a href="#cite_note-watson.ch-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> Two tests found that Guetzli is very slow (about 4 magnitudes slower than normal JPEG encoder) and not necessarily better than <a href="/wiki/Mozjpeg" class="mw-redirect" title="Mozjpeg">mozjpeg</a>.<sup id="cite_ref-davidwalsh.name_7-1" class="reference"><a href="#cite_note-davidwalsh.name-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-pixelz_9-0" class="reference"><a href="#cite_note-pixelz-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Butteraugli">Butteraugli</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Guetzli&action=edit&section=2" title="Edit section: Butteraugli"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Butteraugli is a project that estimates the psychovisual similarity of two images. It assigns a differential <a href="/wiki/Mean_opinion_score" title="Mean opinion score">mean opinion score</a> (DMOS) value to the difference between an original image and a degraded version. It is significantly more complex than traditional metrics like <a href="/wiki/Peak_signal-to-noise_ratio" title="Peak signal-to-noise ratio">PSNR</a> and <a href="/wiki/Structural_similarity" class="mw-redirect" title="Structural similarity">SSIM</a>, but claimed to perform better with high-end quality, where degradations are not or barely noticeable.<sup id="cite_ref-IO2016_10-0" class="reference"><a href="#cite_note-IO2016-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> It models color perception and visual masking in the human visual system, taking into account that the eye is imaging different colors with different precision.<sup id="cite_ref-Designmodo_11-0" class="reference"><a href="#cite_note-Designmodo-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> It uses a <a href="/wiki/Heat_map" title="Heat map">heat map</a> of changes.<sup id="cite_ref-SimAnneal_5-1" class="reference"><a href="#cite_note-SimAnneal-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> How the hundreds of parameters that model the properties of the human visual system were derived remains unexplained.<sup id="cite_ref-arstechnica20170317_1-1" class="reference"><a href="#cite_note-arstechnica20170317-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> An in-house performance evaluation with 614 ratings from 23 people on their own test set of 31 images yielded 75% of ratings favouring of JPEGs encoded for Butteraugli scores over <a href="/wiki/Libjpeg" title="Libjpeg">libjpeg</a>-turbo encodes,<sup id="cite_ref-Alakuijala20170313-1_12-0" class="reference"><a href="#cite_note-Alakuijala20170313-1-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> which usually score higher on SSIM and PSNR-HVS-M.<sup id="cite_ref-encode.ru_13-0" class="reference"><a href="#cite_note-encode.ru-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-score_reversal_14-0" class="reference"><a href="#cite_note-score_reversal-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> </p><p>Translating to "butter eye", the Swiss-German name originally signifies a dimple on top of some sweet pastry that has been filled with butter and sugar before baking.<sup id="cite_ref-Mehlstaub_15-0" class="reference"><a href="#cite_note-Mehlstaub-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Availability">Availability</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Guetzli&action=edit&section=3" title="Edit section: Availability"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Guetzli is a <a href="/wiki/Command-line_interface" title="Command-line interface">command-line</a> app. Written in <a href="/wiki/C%2B%2B" title="C++">C++</a>,<sup id="cite_ref-openhub_16-0" class="reference"><a href="#cite_note-openhub-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> it is <a href="/wiki/Free_and_open-source" class="mw-redirect" title="Free and open-source">free and open-source</a> under the terms of <a href="/wiki/Apache_License_2.0" class="mw-redirect" title="Apache License 2.0">Apache License 2.0</a>. <a href="/wiki/Windows" class="mw-redirect" title="Windows">Windows</a>, <a href="/wiki/MacOS" title="MacOS">macOS</a>, and <a href="/wiki/Linux" title="Linux">Linux</a> versions of Guetzli are directly available from Google's repository on <a href="/wiki/GitHub" title="GitHub">GitHub</a>. The first public version was released on October 21, 2016, without any speed optimizations,<sup id="cite_ref-macg.co_17-0" class="reference"><a href="#cite_note-macg.co-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> and only announced on a specialist forum.<sup id="cite_ref-Linux-Magazin_18-0" class="reference"><a href="#cite_note-Linux-Magazin-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-encode.ru_13-1" class="reference"><a href="#cite_note-encode.ru-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> Version 1.0 followed five months later on March 15, 2017,<sup id="cite_ref-history_19-0" class="reference"><a href="#cite_note-history-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> accompanied by an announcement to a broader public and two scientific papers.<sup id="cite_ref-announcement_20-0" class="reference"><a href="#cite_note-announcement-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Alakuijala20170313-1_12-1" class="reference"><a href="#cite_note-Alakuijala20170313-1-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Alakuijala20170313-2_21-0" class="reference"><a href="#cite_note-Alakuijala20170313-2-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> </p><p>In addition to official release channel, <a href="/wiki/OpenSUSE" title="OpenSUSE">openSUSE</a> and <a href="/wiki/Debian" title="Debian">Debian</a> distribute it via their official <a href="/wiki/Software_repository" title="Software repository">software repositories</a>.<sup id="cite_ref-opensuse_22-0" class="reference"><a href="#cite_note-opensuse-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Debian1_23-0" class="reference"><a href="#cite_note-Debian1-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Debian2_24-0" class="reference"><a href="#cite_note-Debian2-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> (For <a href="/wiki/Arch_Linux" title="Arch Linux">Arch Linux</a>, there are user repositories available.)<sup id="cite_ref-AUR1_25-0" class="reference"><a href="#cite_note-AUR1-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-AUR2_26-0" class="reference"><a href="#cite_note-AUR2-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> The <a href="/wiki/Homebrew_(package_management_software)" class="mw-redirect" title="Homebrew (package management software)">Homebrew</a> repository distributes a macOS version.<sup id="cite_ref-macg.co_17-1" class="reference"><a href="#cite_note-macg.co-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> For the Windows platform, two open-source GUI front-ends are available.<sup id="cite_ref-guetzliconverter_27-0" class="reference"><a href="#cite_note-guetzliconverter-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Guietzli_28-0" class="reference"><a href="#cite_note-Guietzli-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> </p><p>Software developers that use <a href="/wiki/Node.js" title="Node.js">Node.js</a> can integrate Guetzli in their apps via a package available on the <a href="/wiki/Npm_(software)" class="mw-redirect" title="Npm (software)">npm</a> repository.<sup id="cite_ref-npm_29-0" class="reference"><a href="#cite_note-npm-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Guetzli&action=edit&section=4" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-arstechnica20170317-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-arstechnica20170317_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-arstechnica20170317_1-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFAnthony2017" class="citation news cs1">Anthony, Sebastian (2017-03-17). <a rel="nofollow" class="external text" href="https://arstechnica.com/information-technology/2017/03/google-jpeg-guetzli-encoder-file-size/">"Google reduces JPEG file size by 35%"</a>. <i>Ars Technica</i><span class="reference-accessdate">. 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Retrieved <span class="nowrap">2017-12-02</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Watson&rft.atitle=Neues+Google-Tool+verkleinert+JPEGs+massiv+und+heisst+Guetzli+%F0%9F%98%8D&rft.date=2017-03-17&rft_id=https%3A%2F%2Fwww.watson.ch%2F%21797753961&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGuetzli" class="Z3988"></span></span> </li> <li id="cite_note-names-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-names_3-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCrush2015" class="citation web cs1">Crush (2015-09-22). <a rel="nofollow" class="external text" href="https://encode.ru/threads/2313#post44950">"Brotli"</a>. <i>Encode's Forum</i><span class="reference-accessdate">. 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Retrieved <span class="nowrap">2017-12-04</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=nextinpact.com&rft.atitle=Guetzli%2C+l%27algorithme+de+Google+pour+r%C3%A9duire+le+poids+des+fichiers+JPG+de+35+%25&rft.date=2017-03-17&rft.aulast=Hermann&rft.aufirst=Vincent&rft_id=https%3A%2F%2Fwww.nextinpact.com%2Fnews%2F103720-guetzli-algorithme-google-pour-reduire-poids-fichiers-jpg-35.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGuetzli" class="Z3988"></span></span> </li> <li id="cite_note-SimAnneal-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-SimAnneal_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-SimAnneal_5-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHopkinsMitzenmacherWagner-Carena2017" class="citation arxiv cs1">Hopkins, Max; Mitzenmacher, Michael; Wagner-Carena, Sebastian (2017-09-02). 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"Guetzli: Perceptually Guided JPEG Encoder". <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/1703.04421">1703.04421</a></span> [<a rel="nofollow" class="external text" href="https://arxiv.org/archive/cs.CV">cs.CV</a>].</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=preprint&rft.jtitle=arXiv&rft.atitle=Guetzli%3A+Perceptually+Guided+JPEG+Encoder&rft.date=2017&rft_id=info%3Aarxiv%2F1703.04421&rft.aulast=Alakuijala&rft.aufirst=Jyrki&rft.au=Obryk%2C+Robert&rft.au=Stoliarchuk%2C+Ostap&rft.au=Szabadka%2C+Zoltan&rft.au=Vandevenne%2C+Lode&rft.au=Wassenberg%2C+Jan&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGuetzli" class="Z3988"></span></span> </li> <li id="cite_note-opensuse-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-opensuse_22-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://software.opensuse.org/package/guetzli">"software.opensuse.org"</a>. <i>software.opensuse.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=software.opensuse.org&rft.atitle=software.opensuse.org&rft_id=https%3A%2F%2Fsoftware.opensuse.org%2Fpackage%2Fguetzli&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGuetzli" class="Z3988"></span></span> </li> <li id="cite_note-Debian1-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-Debian1_23-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://tracker.debian.org/pkg/guetzli">"Debian Package Tracker - guetzli"</a>. <i>tracker.debian.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=tracker.debian.org&rft.atitle=Debian+Package+Tracker+-+guetzli&rft_id=https%3A%2F%2Ftracker.debian.org%2Fpkg%2Fguetzli&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGuetzli" class="Z3988"></span></span> </li> <li id="cite_note-Debian2-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-Debian2_24-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://tracker.debian.org/pkg/butteraugli">"Debian Package Tracker - butteraugli"</a>. <i>tracker.debian.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=tracker.debian.org&rft.atitle=Debian+Package+Tracker+-+butteraugli&rft_id=https%3A%2F%2Ftracker.debian.org%2Fpkg%2Fbutteraugli&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGuetzli" class="Z3988"></span></span> </li> <li id="cite_note-AUR1-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-AUR1_25-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://aur.archlinux.org/packages/guetzli-git/">"AUR (en) - guetzli-git"</a>. <i>aur.archlinux.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=aur.archlinux.org&rft.atitle=AUR+%28en%29+-+guetzli-git&rft_id=https%3A%2F%2Faur.archlinux.org%2Fpackages%2Fguetzli-git%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGuetzli" class="Z3988"></span></span> </li> <li id="cite_note-AUR2-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-AUR2_26-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://aur.archlinux.org/packages/butteraugli-git/">"AUR (en) - butteraugli-git"</a>. <i>aur.archlinux.org</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=aur.archlinux.org&rft.atitle=AUR+%28en%29+-+butteraugli-git&rft_id=https%3A%2F%2Faur.archlinux.org%2Fpackages%2Fbutteraugli-git%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGuetzli" class="Z3988"></span></span> </li> <li id="cite_note-guetzliconverter-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-guetzliconverter_27-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.guetzliconverter.net/">"Guetzli Converter GUI"</a>. <i>homepage</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2017-12-03</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=homepage&rft.atitle=Guetzli+Converter+GUI&rft_id=https%3A%2F%2Fwww.guetzliconverter.net%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGuetzli" class="Z3988"></span></span> </li> <li id="cite_note-Guietzli-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-Guietzli_28-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKyladitis2017" class="citation news cs1">Kyladitis, Petros (2017-06-29). <a rel="nofollow" class="external text" href="https://www.multipetros.gr/posts/2440-introducing-guietzli-guetzli-graphical-front-end/">"Introducing Guietzli - The Guetzli graphical front-end - Petros Kyladitis"</a>. <i>multipetros.gr</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2017-12-02</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=multipetros.gr&rft.atitle=Introducing+Guietzli+-+The+Guetzli+graphical+front-end+-+Petros+Kyladitis&rft.date=2017-06-29&rft.aulast=Kyladitis&rft.aufirst=Petros&rft_id=https%3A%2F%2Fwww.multipetros.gr%2Fposts%2F2440-introducing-guietzli-guetzli-graphical-front-end%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGuetzli" class="Z3988"></span></span> </li> <li id="cite_note-npm-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-npm_29-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.npmjs.com/package/imagemin-guetzli">"imagemin-guetzli"</a>. <i>npm</i>. 30 May 2020.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=npm&rft.atitle=imagemin-guetzli&rft.date=2020-05-30&rft_id=https%3A%2F%2Fwww.npmjs.com%2Fpackage%2Fimagemin-guetzli&rfr_id=info%3Asid%2Fen.wikipedia.org%3AGuetzli" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Guetzli&action=edit&section=5" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="https://github.com/google/Guetzli">Guetzli</a> on <a href="/wiki/GitHub" title="GitHub">GitHub</a></li> <li><a rel="nofollow" class="external text" href="https://github.com/google/Butteraugli">Butteraugli</a> on GitHub</li> <li><a rel="nofollow" class="external text" href="https://github.com/doterax/guetzli-cuda-opencl">guetzli-cuda-opencl</a> on <a href="/wiki/GitHub" title="GitHub">GitHub</a></li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist 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