Questions tagged [compression]
Compression is the reduction in size of data in order to save space or transmission time. For data transmission, compression can be performed on just the data content or on the entire transmission unit (including header data) depending on a number of factors.
59
questions
2
votes
2
answers
180
views
Why do oversized images appear better than images that are the correct size on the web?
I've noticed that when I use large images, and use CSS to show them at small sizes, they look much better quality than images that are the correct size. Why is this the case?
Is CSS loading the full ...
- 121
1
vote
3
answers
692
views
What is AVIF, and why do website builders automatically convert JPEG images to it?
The issues noted in a post about webp file types are complicated to understand, but there's an even worse one that I just discovered. It's called an .avif file type. A number of website builders, like ...
- 11
0
votes
0
answers
454
views
Why does Pingdom Tools tell me to Compress components with gzip
On Pingdom Tools I get a message to Compress components with gzip. We use asp.net on Windows 2016 server (IIS10). I have set in web.config the following
<httpCompression>
<staticTypes&...
- 101
0
votes
1
answer
36
views
Why this image is so large despite small dimension [closed]
I have any image which is 760x400 in dimension but it about 7MB in size. it comes out clean on VirustTotal.com and even Image Meta doesnt show anything unusual other than lots of text info.
Since i ...
- 711
3
votes
2
answers
77
views
Is it worth using next generation image formats with only partial browser support for SEO?
We are building a website for a client and we are trying to make it as SEO optimized as humanly possible and the question now is how to deal with images.
Here is an example of pagespeed result:
It ...
1
vote
0
answers
242
views
How can I enable compression of 3rd party scripts to get a better Gtmetrix score?
If I test my website on the Gtmetrix, there appear like this :
- 325
3
votes
1
answer
253
views
Website backup file size differs on server vs when downloaded via FTP
When I backup my files using Filezilla, as soon as a file is downloaded, it has different file size with the original file size on the server. I am not sure if it is normal or a kind of virus or ...
- 321
2
votes
1
answer
164
views
Is there any point to compressing HTML when using GZIP?
I was considering using a ruby gem to compress my HTML, but we're already serving gzipped files, and I was wondering if there is any reduction in served file size by doing both HTML compression and ...
- 183
0
votes
1
answer
128
views
MediaWiki: Enable text compression
From a Google Pagespeed Insights test it seems my MediaWiki website lacks text-compression;
reading about this, it seems I lack this because I don't have Gzip compression on.
I Ran this gzip test and ...
user58733
4
votes
1
answer
846
views
How do you serve Jekyll pages with gzip compression on GitLab Pages?
GitLab Pages doesn’t compress files automatically before sending them to clients. Is it possible to enable gzip compression when using Jekyll (or another static site generator) on GitLab Pages?
3
votes
0
answers
141
views
Nginx doesn't show a directory index unless I have the non-gziped index.html when I can just provide the .html.gz of other files
My site is full of pre-compressed gzip files. In all cases, except for the index.html file, I don't need the non-gzip versions.
For example, if I have 1.html.gz, then I don't need to also have 1.html ...
- 189
1
vote
1
answer
2k
views
Chrome Developer Tools shows that gzip compressed data requires longer time than uncompressed
I'm new to the concept of compressing and gzip.
So while I was trying to use chrome to test if enabling gzip on my host was a success I found something interesting.
According to chrome, in the ...
- 43
4
votes
1
answer
2k
views
Why does "Disable Cache" in Chrome developer tools change the "content-encoding: gzip" response header?
What does the "Disable Cache" have to do with gzip and compression? How come if "Disable Cache" is checked the Response Headers shows content-encoding: gzip, but when "Disable Cache" is not checked(...
- 41
1
vote
0
answers
640
views
How to enable gzip compression for CSV files on Github Pages?
Pretty much title. The majority of my Github Pages site is being gzipped, but for some reason CSV files are ignored. This is unfortunate, because for some client-side visualizations a 10 megabyte CSV ...
- 163
2
votes
1
answer
3k
views
How do I configure gzip to work on External Resources
In order to do this I put code to .htaccess:
<ifModule mod_gzip.c>
mod_gzip_on Yes
mod_gzip_dechunk Yes
mod_gzip_item_include file .(html?|txt|css|js|php|pl)$
mod_gzip_item_include handler ^cgi-...
- 21
4
votes
1
answer
496
views
Why does Google mobile site test say my site is not compressed when it uses content-encoding:br?
I used this Google tool to test my web site.
When I got the report it recommended the following..
Compress resources with GZIP
See how to enable GZIP compression »
When I look at the response of my ...
- 143
2
votes
1
answer
397
views
Would compressing a PNG more than once reduce the number of colors or affect something else?
For a website I control that sells consumer goods, fast page performance is important, especially for potential customers on mobile devices. Therefore, we want our images to be as small as possible ...
- 407
1
vote
1
answer
674
views
What image compressor Google Pagespeed Insights uses? [duplicate]
It's very inefficient to compress all my site's images in Google's preferred compresion by running webpage after webpage in Google GPI, downloading all images and upload one by one to my CMS image ...
user58733
1
vote
2
answers
3k
views
How to compress jpeg images for Google Page Speed Insights? [duplicate]
I hope this question fits here. I would have asked on Stackoverflow, but there is a similar question there that was closed with the suggestion to ask at Server Fault, and Server Fault closed my ...
- 113
1
vote
2
answers
43
views
Mobile Load Time - Compressing JavaScript
Our mobile site's homepage has a load time of 10.72 seconds, which ruins our mobile SEO and therefore traffic. The site is operating on WordPress.
6.8 second of the 10.72 is spent scripting .js files....
- 419
1
vote
0
answers
121
views
runtime HTML minification
The processing time for my project on Google App Engine is about 20 ms for a JSP page. Using HtmlCompressor at runtime (using a JSP tag) to minify the HTML, the processing time increases to about 100 ...
- 165
0
votes
1
answer
12
views
can a random compression level applied on same html output replace HTTPS to an extent?
HTTPS is supposedly a secure protocol for data exchange.
I'm wondering upon a page request, if I outputted data to the client at a different gzip compression level (over the HTTP protocol) each time,...
- 13.6k
2
votes
2
answers
1k
views
Sitemap compressed is in unsupported format but valid if uncompressed
I've build a sitemap_index pointing to different sitemaps "sitemap1.xml"
If they are uncompressed, they are successfully validated and accepted (Google Webmaster).
However, when compressed, they are ...
- 161
5
votes
1
answer
1k
views
Enabling compression for font loaded via googleapi
I'm using Google Fonts (https://www.google.com/fonts) to add special fonts to a website.
I chose to include the font via a link in the head:
<link href="https://fonts.googleapis.com/css?family=...
- 973
5
votes
3
answers
330
views
Should I compress very small HTML pages?
Here's the thing:
More compression of a page means more work of the server CPU. 99% of my website for most visitors is gzip compressed.
I have made error pages which are not compressed. They use 2 ...
- 13.6k
2
votes
1
answer
399
views
What Gzip compression level can safely be used for sitemap files?
I can use PHP's gzencode function to set the compression level of data to compress and I want to compress my sitemap files then submit them to google.
Currently my compression level is set to 2 ...
- 13.6k
5
votes
1
answer
2k
views
Does my origin's gzip compression level matter when it's behind CloudFlare?
Today I uploaded a sitemap.xml file to my site, then realised that my server wasn't set up to gzip .xml files. However, CloudFlare still gzipped it before sending to my browser.
This got me wondering,...
- 288
0
votes
0
answers
68
views
How to offer high quality image downloads without making google upset
My website consists of thousands of photos online that people can see. The photographer creates the photos using the highest quality settings possible and then uploads them. Then my php scripts use ...
- 13.6k
1
vote
1
answer
577
views
Reducing waiting delay to webpage rendering time?
I ran a few tests on my website at webpagetest.org and while the Time to First Byte is under 200ms, it seems that in all tests I have run in different browsers at different locations, the page is ...
- 13.6k
1
vote
1
answer
48
views
Is Image Spriting for Articles Images a good solution?
I am starting an online portal and I calculated that I need about 102 Images (based on the amount of articles), the problem is I want to keep the whole page below 800KB (Including all assets). I want ...
- 23
3
votes
1
answer
192
views
weird results from tests when trying to serve a fast image download page... why?
This is my php code.
<?php
ob_start();
echo file_get_contents("originalhighqualityphoto.jpg");
$dat=ob_get_contents();
ob_end_clean();
$dat=gzencode($dat,2);
header("...
- 13.6k
2
votes
3
answers
786
views
How do I enable compression to reduce the file transfer size on GoDaddy?
I have hosted one of my website on godaddy.com. How do I enable compression to reduce the file transfer size? I need to compress the .css and .js files. I tried the following but it doesn't work :
...
- 295
2
votes
1
answer
192
views
How Google Web Starter Kit serves adaptive image for mobile?
My website weirdly (in a good way) serves smaller images when viewed on mobile. I wanted to know what cause this? As far as I know this is not the default behaviour, so I think it must be Google Web ...
- 85
2
votes
1
answer
2k
views
How can I get my website to enable gzip compression?
I'm currently trying to increase the speed of my website and I noticed that, when I run it through ismyblogworking.com, I get a message that reads "your blog application doesn't support gzip ...
- 321
0
votes
1
answer
575
views
How do I use HTML compression in Jimdo WYSIWYG editor?
I have used Jimdo website to build my website. Using Google PageSpeed Insights tell me that I can achieve better page load speed using HTML compression. I wanted to use deflate.js and inflate.js, but ...
47
votes
2
answers
30k
views
What is recommended minimum object size for gzip performance benefits?
I'm working on improving page speed display times, and one of the methods is to gzip content from the webserver.
Google recommends:
Note that gzipping is only beneficial for larger resources. Due ...
- 634
4
votes
1
answer
468
views
.htaccess and gzip compression
i have question about GZIP compression,
actualy my wordpress website doesn't have .htaccess to be able to use that feature, so can i create .htaccess file only for gzip, it won't change anything on ...
- 223
2
votes
1
answer
1k
views
HTML compressor/minifier
Currently I am using a system where HTML gets cached server-side before it's sent to the browser. I'm looking to compress the HTML source of my website before it is cached.
Basically I'm looking for ...
- 248
2
votes
1
answer
1k
views
zlib compression issues
I'm having some issues running zlib compression on my site ..
Firstly if I enable zlib compression in .htaccess using: php_value output_handler ob_gzhandler then I receive thousands of lines of the ...
- 157
3
votes
1
answer
3k
views
Can Amazon Cloudfront files be served GZIP'd?
If i'm running a WordPress website with the W3TC plugin installed, and have my static CSS/JS minified files hosted on Amazon's CDN, is there a way to serve them GZIP'd?
I have the basic understanding ...
- 5,464
3
votes
2
answers
266
views
Offline lossless image shrinking
I'm looking for something like Smush.it or PunyPNG that works offline, preferably via command line interface that does gifs, jpegs and pngs.
Any suggestions?
- 248
0
votes
1
answer
153
views
If Apache applies compression with mod_deflate, is there a reason to serve compressed files?
I have an Apache HTTP server which is configured with mod_deflate to compress content "on the fly".
Is there any benefit if I serve a compressed sitemap.xml.gz file, or should I rely on mod_deflate ...
- 496
4
votes
4
answers
20k
views
How can I measure the size of a webpage?
I'm building a website at the moment that has several complicated background images and repeats. The file sizes for each of the images are quite large (I've compressed them down as much as possible!), ...
- 1,542
4
votes
1
answer
2k
views
How to enable more file formats for GZIP/Deflate Compression
I enabled gzip/Deflate compression on our servers per Google's Page Speed directives, and it looks like it's now compression html/php files, but a couple file formats aren't being compressed that ...
- 447
1
vote
2
answers
334
views
Weird unexpected image compression on a web server running Apache on Ubuntu?
I have a weird problem on my production web server running Apache on Ubuntu: it compresses my images thereby dramatically lowering their quality!
Actually I have two virtual hosts running, each ...
2
votes
1
answer
908
views
IIS 7.5 Compression is not working when loading the page on a local computer
If I try to access our website inside our servers using the remote desktop connection. YSlow and PageSpeed is reporting that our website are compressed. But If I try to access our website in my local ...
4
votes
1
answer
1k
views
pre-gzipping files and serving to clients possible?
I understand that we can do some settings in .htaccess to allow gzipping on the fly.
However is there anyway we could do it "not-on-the-fly"?
I have a static file that I wish to serve gzipped, but I ...
- 611
3
votes
4
answers
8k
views
Enable gzip compression on Bluehost?
My website is loading large (~3mb) SVG file with jQuery. It takes quite a while therefore I decided to enable gzip compression.
I have a hosting account with Bluehost which supports custom .htaccess ...
- 143
4
votes
1
answer
1k
views
Optimal GZIP compression level for static resources?
Is there a compression level which will provide an optimal balance between file size reduction and client decompression time/cost?
I was wondering which GZIP compression level provided the best ...
- 143
1
vote
1
answer
556
views
[BlogEngine.NET] Compression error
I have a blogengine.net website hosted on godaddy and I'm having issues when viewing it with Firefox and Chrome. On Firefox I get this error :
Content Encoding Error
The page you are trying to view ...
- 113