Questions tagged [compression]

Questions about reducing a file's size by automated pattern recognition, and the resulting changes in image quality.

Filter by
Sorted by
Tagged with
26
votes
9answers
116k views

Facebook: Ways to preserve image quality of uploaded images?

After uploading an image, Facebook converts it to a new image. Their conversion process introduces artifacts and mottling to the magenta-ish parts of the image. Original image: Facebook's ...
15
votes
5answers
3k views

How do I convert a .png blurred background into a compressed .jpg one without introducing artefacts?

I'm currently dealing with a problem of image quality for my website background image. I have a big blurred background image I'd like to use but would like it to be as small as possible in size for ...
15
votes
4answers
10k views

How to crop a JPG without recompressing?

Is it possible to crop a JPG image without losing quality/recompressing the remaining part of the image?
15
votes
6answers
27k views

Why do JPEG files blur red more than other colors?

I am trying to figure out why JPEG compression causes noise in the red spectrum that is larger and fuzzier in regards to, say, the blue spectrum. I've seen this question and I am not looking for a ...
13
votes
5answers
11k views

The most advanced JPEG image compression on mac?

Sometimes i work with JPEG files for my web designs. There are occasions where the PNG format is not suitable.. There are several optimization techniques for the PNG format, but I noticed that for ...
10
votes
4answers
142k views

Photoshop: how to reduce the size of a PNG for web use

I have a PNG file that is 2042 x 1250 and is 6.1 MB. When I open with Photoshop and do "Save As > PNG 24" and choose the compressed file size of the two options (the other being no compression) I ...
7
votes
9answers
3k views

Tools for *lossy* PNG compression?

I'm trying more and more to get by sans PhotoShop for my personal/freelance work. I do primarily web work these days and don't do enough side gigs to justify keeping up with the Creative Suite beast. ...
7
votes
5answers
683 views

Is there any method to deliberately digitally corrupt an image?

For an art project. I want to take a high-resolution digital image and digitally 'corrode' it. My original intention was to subject an image to repeated jpg compression, and show the iterations, but ...
6
votes
4answers
3k views

PNG vs GIF for 1 bit transparency

Is there any reason for using GIF instead of PNG when the image requires only 1 bit transparency (either on or off) and of course no animation is required? thanks
5
votes
2answers
13k views

How to reduce the size of a (chinese) .ttf font file?

I have a Chinese font file, the size of the file is 7.693 MB. Due to the size of the ttf file, the website loads slowly. Is there any way to reduce the size of the .ttf font?
5
votes
2answers
1k views

Why JPEG files saved in my digital camera are higher size vs JPEG files saved in my computer?

When I took pictures using my digicam, it saves those on higher size (over 1 MB) JPEG files. What I usually do is that I open them on some image editing application such as Paint (windows) or Preview (...
4
votes
1answer
6k views

Why does a JPEGs file size increase after cropping and saving for web in Photoshop?

When I save my image for the web in Adobe Photoshop, the produced jpeg is larger than the original jpeg file. The only alteration done to the image is cropping. How is this possible? I am saving the ...
4
votes
2answers
7k views

Google Play - 'Feature Graphic' Design

I recently got my application in the google play store, but I have an issue with how the 'Feature Graphic' is being displayed. Here is the original (@ 72 DPI (Screen RES) - Saved for Web - PNG8): ...
4
votes
2answers
4k views

Reduce 30MB image to less than 50KB without significant loss

I am creating figures for a scientific paper. The journal I am submitting to seems confident "all figures can easily be reduced to less than 50kB each (gzipped) without significant loss of quality". ...
4
votes
4answers
15k views

How do I optimize an animated gif for Google AdWords?

Creating GIFs designed for the Google AdWords platform can be tricky, given the file-size constraint of 150Kb. I looked for examples online and found this page: http://bannerspiration.com/gif Not ...
4
votes
2answers
2k views

Compress large PDF files in Illustrator

I have a large PDF file (5 MB+) which is generated from a large dataset. The amount of details in the plot are very fine, which makes it nearly impossible to handle in Illustrator. I want to ...
3
votes
2answers
431 views

Can Animated GIFs be reduced in filesize by comparing regions that actually changed?

Can GIFs be optimized so that only the changed regions (pixels within certain rectangular bounds per frame) are rendered / calculated in the final filesize? This is assuming that by default - each ...
3
votes
2answers
2k views

Photoshop: How to use a non-white background as the basis for semitransparent layers in PNG8 export?

PNG8 is a great compressed format when we don't really need semi-transparency. Often an asset will have semi-transparency data that we're happy to lose in the export process, however Photoshop ...
3
votes
1answer
13k views

Inkscape: how to compress image in SVG?

I have a JPG image file (3000px x 1000px) which size is about 1 MB. I embedded it into Inkscape, drew vectors above the image and saved all of them into an SVG file. Now the file size is about 12 MB. ...
3
votes
2answers
63k views

Why is my PDF size from my InDesign Export still large?

I'm doing class project that is a four-page, seven-image document with very little text. The project must be submitted as a PDF under 300 KB. However, when I export the document under the smallest ...
3
votes
2answers
662 views

Better image compression by combining images?

What is the name of the technique where many small images are copied into one large image to get better compression and avoid loading many separate images int memory? And is this still useful in ...
3
votes
2answers
13k views

How to compress an animated GIF?

I have an animated gif banner 125x125 that needs to be < 10 KB. I started at 60 KB and my best efforts (remove all animation, reduce number of frames) resulted in 28 KB. Any ideas how to make it &...
3
votes
2answers
1k views

Why does enabling transparency in an animated gif reduce its file size?

Update 1: I've fiddled around with different images after reading Yorik's comment “. . . AFIAK gifs do not store the whole image per-frame, but rather sub-frames that change.” It does seem like ...
3
votes
1answer
4k views

Transparent png shadows are filled

When I store transparent images with shadows as .png I have filled areas instead of soft edges. It seems like it is a saving/compression or whatever problem because the .psd is in photoshop really ...
3
votes
1answer
5k views

SVG or SVGZ, what should I use? [duplicate]

I tried compressed plain SVG (.svgz), the files are smaller and it looks the same than the regular .svg. Is there any downside? Can I use always .svgz?
3
votes
3answers
9k views

How to reduce the file size of a web banner image with Photoshop?

I need to change the file size of an image I created in Photoshop without changing the dimensions for a banner ad on the web. How do I do this?
3
votes
1answer
123 views

What determines if an image can be compressed and when it stops

I ran an image I grabbed off Google through TinyPng's website. The image was compressed, something like 21%. Out of curiosity I put it in again and it was compressed again, by a much lesser value. I ...
3
votes
3answers
4k views

Photoshop Reducing File Size by Hiding Layers

I've recently learned that hiding Photoshop layers will reduce the file size. After searching around the Adobe forums I can't find anything stating this. There are only about half a dozen sites on ...
3
votes
0answers
92 views

A best way to compress a png atlas with transparency

I have an atlas of assets in a transparent png with 8-bit alpha (660kb) and I want to compress it. Could you suggest what options do I have? When using a pngquant (I'm using SuperPNG plugin for ...
2
votes
2answers
790 views

Large web background image - how to split into JPG and PNG part

On a website I'm working on, the design team wants a large background image. Uncompressed, it is several hundred kilobytes (both in JPG and PNG). Most parts of the background image are blurred, but ...
2
votes
2answers
333 views

How to fill with similar colours?

I have this image that have been damaged by JPG, and would very much like to restore it, as if it had never been compressed with JPG. Can someone help me with this? I assume I need to fill with ...
2
votes
2answers
41 views

Does the GIF file format remove shared data between frames?

I'm looking into various file formats and how they are optimized for their main purposes, but I've found that the GIF file format uses lossless compression meaning it would have a higher file size ...
2
votes
2answers
3k views

Compress png images with Gimp

I'm getting a message from PageSpeed Insights that recommends to compress some png images. E.g: If compressing .../logo.png without loosing information, you would save 1.014 B (12% redcuction). ...
2
votes
4answers
5k views

How to get a non pixelated illustration upload to social media (mostly FB)? [duplicate]

Intro: I'm not a GD, but bear with me. I've been doing digital illustrations for a while and never had an issue with posting them anywhere, until this year. I keep getting all my illustrations sort ...
2
votes
2answers
3k views

Will I lose image quality when editing and re-saving an existing png file?

I know that each time a .jpg file is saved, it is compressed and loses quality. Is the same true for .png files?
2
votes
4answers
9k views

Changing File Sizes in a PDF

Is there a way when exporting a .psd as a .pdf to make the file smaller? My client always has me work in Photoshop and send them finished work as .pdf's, but they say the files are too big. These ...
2
votes
1answer
2k views

How do I compress/zip files in Bridge?

I use Bridge for my workflow but I always have to right click > Reveal in Finder to zip a folder. There is no option to do so when I right click in Bridge, as there is in the Finder window. Am I ...
2
votes
2answers
1k views

Saving PNGs in Photoshop—compression specific question

I create artwork on Photoshop and occassionally print this artwork on physical products. That said, I save all of my artwork in PNG since is of better quality and has transparency. Shen you save a ...
2
votes
0answers
107 views

PDF export in Illustrator: Control which images to compress

I have several Illustrator files that have multiple embedded bitmap images. Some are photos and some are detailed line art. When exporting to PDF, it is possible to control downsampling and ...
1
vote
3answers
572 views

How to fix horizontal lines from JPG compression in an image?

I have a geometric wallpaper that I downloaded for my phone, but it has these horizontal lines in it, from what a presume is an artifact of JPG compression. Any thoughts on how to fix?
1
vote
2answers
1k views

File size dilemma in Photoshop for print-quality large banner

I'm an intern at a marketing department and got an assignment to update a banner with new information, and was directed to a pdf file to edit. It was only 3MB, which seemed very low for a large print-...
1
vote
1answer
1k views

Image compression - what is the best way?

What is the best way to compress images to satisfy Performance Review on Web Page Speed test on webpagetest.org. Here's how I do it: 1) Save for Web in Photoshop from original PSD with quality set ...
1
vote
1answer
2k views

How can I remove compression artifacts around text?

Example: This seems to be a problem with using JPEG. My questions are: How to remove the grey areas around the text? What filter/process in GIMP/ImageMagick or other free image editing/scripting ...
1
vote
2answers
754 views

Is it possible for me to get an interactive PDF with high resolution images, yet a small file size? I'm talking under 5mb

I am trying to create a digital portfolio of my work that I can email to employers. I want the images to be high resolution so my work is not viewed blurry and you can see some of the details in the ...
1
vote
1answer
23 views

Adobe Illustrator formating to JPG turing out stretchy @ [closed]

I have finished some work on Adobe Illustrator, converted it to PDF and then JPG. but no matter how many times I changed the settings with compression, My art board looks all squished...anybody know ...
1
vote
1answer
40 views

Does InDesign convert all images to JPEG when exporting to PDF?

When I'm exporting in InDesign,the compression settings say that I am able to change the dpi and chose the format of the compression. Does this mean that if I select 72 dpi and JPEG format all the ...
1
vote
1answer
78 views

How to make right color compression for internet images? [closed]

How to make right color/image compression for internet images? I adjust images in the Adobe Lightroom, then I export them to the Adobe Photoshop (there are already some changes - pictures looks more ...
1
vote
1answer
899 views

In Acrobat 11 where is the PDF settings panel for PDF Optimizer?

Acrobat 11 is much different than Acrobat 9 but I was wondering where is the panel for PDF compression settings. In Acrobat 9 you could go to Advanced -> PDF Optimizer:
1
vote
3answers
12k views

image in illustrator compression script

I have a very High resolution image in illustrator, which leads to a very heavy eps file size, I'm asking for a batch tool or a script to compress the eps image , in other words reduce its resolution ...
1
vote
0answers
78 views

Target what svg compressor option messes up file for sketch 3

I am using https://jakearchibald.github.io/svgomg to compress my svg image, its pretty good at what it does, but after running image through it, sketch 3 messes it up and it looks like this: Where as ...