Martijn Geerts Posted September 23, 2013 Share Posted September 23, 2013 I wish there was support for progressive JPEG. To control it, set it in the imageSizerOptions array. 4 Link to comment Share on other sites More sharing options...
horst Posted September 23, 2013 Share Posted September 23, 2013 I wish there was support for progressive JPEG. To control it, set it in the imageSizerOptions array. Martijn, what's about to support it with PiM instead with ImageSizer? If I'm right, there isn't much support for interlaced JPEGs actually: limited browser support (render interlaced: chrome, Firefox, IE9+ | don't render interlaced: all Safari, all Opera) if browsers support it, they mostly only support foreground images but not interlaced background images (only Chrome render background images correct) if there is support for interlaced images, the cpu usage is multiple times then with basic-jpegs, (not very handy with mobile devices) And there is more (pro & con): http://calendar.perfplanet.com/2012/progressive-jpegs-a-new-best-practice/ I'm not sure, but the pro's seems limited to some more or less special usage only. ------ BTW: interlaced images could be really useful with responsive designs if the browsers would support them technically in a special way. For example if you have a source image of 1200 x 1600 and it is sent to a mobile phone, the mobile browser could stop downloading and rendering after the first (normally very blurry) image step is rendered. A desktop would download the complete file and also would render all steps (scanns). Would be very helpfull if (all) the browsers support that some day. Link to comment Share on other sites More sharing options...
Martijn Geerts Posted September 23, 2013 Author Share Posted September 23, 2013 (edited) Not sure about the limited browser support. I thought back in the days 56k they told better to use progressive. As it give the the feeling that it loads quicker. ( below some info from wikipedia ) These days, we want to give more more control back to CSS. Old lightbox scripts, first load the whole image, then presenting them to the screen with animation. What I see happen now a days ( more & more ) other of lightbox scripts appear. The animation delivered bij CSS & not by Javascript. And images appear on the screen directly. ( after first byte is loaded ) see magnific lightbox for example. Progressive loading is way nicer then. For mobile progressive is ideal. ---- wikipedia compression : There is also an interlaced "Progressive JPEG" format, in which data is compressed in multiple passes of progressively higher detail. This is ideal for large images that will be displayed while downloading over a slow connection, allowing a reasonable preview after receiving only a portion of the data. However, support for Progressive JPEGs is not universal; when Progressive JPEGs are received by programs that do not support them (such as versions of Internet Explorer before Windows 7)[13] the software only displays the image after it has been completely downloaded. --- Interresting read @horst. Still have to think about it. To be continued ! Edited September 23, 2013 by Martijn Geerts 2 Link to comment Share on other sites More sharing options...
PeterDK Posted March 11, 2014 Share Posted March 11, 2014 +1 Link to comment Share on other sites More sharing options...
encho Posted June 27, 2014 Share Posted June 27, 2014 +1 ... and also to get better scores on WebPageTest page 3 Link to comment Share on other sites More sharing options...
Pavlos Posted July 10, 2015 Share Posted July 10, 2015 +1 Link to comment Share on other sites More sharing options...
d'Hinnisdaël Posted December 4, 2015 Share Posted December 4, 2015 +1 — This is especially important for portfolio sites with multiple large images. Lazyloading is a possibility, but even then progressive loading is visually more satisfying than scanlines. I don't know about the technical details of implementing this in PHP, but I imagine this can't be too complicated. Or do you think this would best be handled by writing a PW module? Link to comment Share on other sites More sharing options...
Jason Huck Posted February 4, 2016 Share Posted February 4, 2016 +1. Clients don't know the difference between baseline and progressive JPEGs, they just upload whatever they've got and then call when it doesn't work. 1 Link to comment Share on other sites More sharing options...
Webrocker Posted August 16, 2016 Share Posted August 16, 2016 +1 - I just tested a site with webpagetest.org and had a bunch of jpgs, saved as "progressive" in Photoshop, but a bit too large in dimensions for the final display. As soon as image->width() or image->size() was used to scale these images, none of them were "progressive" anymore. maybe @horst has something up his sleeve? 1 Link to comment Share on other sites More sharing options...
David Beesley Posted September 22, 2016 Share Posted September 22, 2016 Can I bump this? Or could someone point me to where it has been added if it already has? Link to comment Share on other sites More sharing options...
dotnetic Posted January 25, 2018 Share Posted January 25, 2018 Support for progressive JPGs is integrated into the Dev version. I think it is there since 3.0.80, but don't know exactly. To use it put this into your site/config.php $config->imageSizerOptions('interlace', true); 3 Link to comment Share on other sites More sharing options...
szabesz Posted January 25, 2018 Share Posted January 25, 2018 3 hours ago, jmartsch said: I think it is there since 3.0.80, but don't know exactly. https://processwire.com/blog/posts/pw-3.0.86/ 4 Link to comment Share on other sites More sharing options...
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