Wikipedia talk:Preparing images for upload

message: Kunja kheda कुंजाखेड़ा village  tehsil kumbhraj District  Guna  Madhya Pradesh india
Devend meena (talk) 04:49, 12 January 2017 (UTC)

message: Moved from the Village pump
Hi
I'm trying to reduce the size of an uploaded image, anyone got experience of that. I tied to crop it in Graphic Converter offline, then up load it , but the new upload was bigger, although still a croped version of the old... help!
TonyClarke 11:40 May 6, 2003 (UTC)
:Do you mean :Image:Hobies.jpg and :Image:Trimhobies.jpg? Because the trimmed image is definitely smaller than the original image. Egil uploaded a scaled version of :Image:Hobies.jpg which was much smaller (pixel-wise and byte-wise) than the original. How about I rescale the trimmed one for you? -- Tim Starling 12:13 May 6, 2003 (UTC)
:Okay, that's done now. I adjusted the levels a bit too. Just revert it if you don't like it. 
::Image compression is a bit of a dark art. If you're recompressing a JPEG image, there will be far more loss of quality than it is worth.
:::Yes, I know. I was going to ask you for a higher quality image (if you have one), but it was getting late here in UTC+10 land, and I was only using a modem so multi-megabyte image files are a bit annoying. -- Tim Starling 00:15 May 7, 2003 (UTC)
:Wikipedia:How to keep image file sizes as small as possible might help. --Menchi 15:20 May 6, 2003 (UTC)
End of moved text
Village kunja kheda aad on Google  Devend meena (talk) 04:59, 20 December 2016 (UTC)
thread_title: discussion from village pump

message: What about a bot going through Wikipedia's image archive and processing all the PNG's with OptiPNG? This would demand lots of CPU, though.Etz Haim 22:59, 25 Aug 2004 (UTC)
replies: text: This would most likely be pointless. If we really need to save disk space then it would be more effective to compress everything on the database level than to recompress our png's by a few percent. Joshua.leahy (talk) 19:18, 3 November 2009 (UTC)
thread_title: reprocessing stored images

message: Should we really be discouraging anti-aliasing?
In my opinion it vastly improves the easthetics and 'visual feel' of most diagrams
and should be used wherever possible.
Diagrams don't normally consume nearly as much space as photographs. 
It probably only makes up for a fraction of the total disk space. -Anon
:It was never my intention to discorage anti aliasing. Only to point out the fact that if you anti alias you need a greater colour depth than you might otherwise have thought. Theresa Knott  (Not the skater) 10:13, 21 Oct 2004 (UTC)
thread_title: anti-aliasing?

message: An interesting project I've found on Freshmeat: Webpack
From the site: "Webpack is an open-source command-line tool for automatically packing websites by shrinking them down without affecting the way they look or behave.Webpack is also useful for losslessly shrinking image collections and locating corrupted files. Webpack works by stripping unnecesary information from & optimising the compression of images, and removing comments/whitespace from  html. This makes for a faster website for your users, and lower bandwidth usage/costs for you! (oh, and it's free - both as in speech and as in beer)." — Etz Haim 18:19, 13 Nov 2004 (UTC)
thread_title: webpack

message: I have wondered for sometime how/if the thumbnailer produces optimal size PNGs. I had a lot of hassle with my PNG-optimizing with a batch of pngs for Wikipedia, and finally figured to drop that step, resulting in 5-25 % larger uploaded images. I was thinking that Wikipedia's thumbnailer really had to do this optimizing, smart as it is (I presume), and me having trouble with it. 
Well, how is it? Does the thumbnailer use pngcrush or equivalent on the thumbs. Why not use it on all uploads? ✏ Sverdrup 02:43, 5 Dec 2004 (UTC)
replies: text: i don't think it does optimise them. I think it pretty much just uses imagemagiks convert program on more or less its default settings. Plugwash 00:37, 24 Jan 2005 (UTC)
replies: text: It should be noted that ImageMagick's png writer is better than average. I just tried png crushing some mediawiki thumbnailed stuff and even with the most agressive setting on PNG crush I wasn't able to get more than 5-6% reduction. --Gmaxwell 14:55, 20 February 2006 (UTC)
thread_title: How does the thumbnailer do it?

message: Is it really a good idea to have 70-80 % compression for JPEGs?
I mean, suppose that in the future you make a print Wikipedia, you want the most quality images you can have.
I propose that we upload JPEGs in a high quality byte- and pixel-size (if available) and let the software downgrade it for browsers.
Also don't remove EXIF data before uploading.
And for those who propose to run permanent compression on the image collections, you may lose interesting metadata like IPTC or EXIF or some embedded copyright notice.
:(The above is from :User:80.58.3.172, who has a whole bunch of anon edits.) I concur partly---high-resolution and high-quality are good ideas, because higher-resolution displays and high-quality PDF output are goals that I think we should be working toward. Though image editors frequently remove EXIF data when, for instance, images are cropped. It's not always reasonable to include EXIF. grendel|khan 22:43, 2005 Jan 19 (UTC)
::yeah most jpegs will go through the autoscaler anyway meaning the quality setting on the original will have no effect on the file the browser gets. Ideally we should archive images in a lossless format but unfortunately we can't change the format in rescale operations. Where jpeg is used quality 95 (the highest you can use before getting into insanely diminishing returns) should be used without too much caution/ Plugwash 08:34, 18 Feb 2005 (UTC)
replies: text: The suggestion of '95%' for JPEGs is a good one. As far as format in the autoscaler: We *can* change the format, in the sense that there is no technical barrier stopping such a feature, we just don't... the reason for this is that there are images which are uploaded in PNG which should stay PNG and we have no way of identifying them to the software.  You could go impliment a  flag which would prevent the transforming to JPEG, but I worry that no one would use it. ... However now that we have SVG much of what was previously PNG is being converted... so perhaps the time is right.  Patches to mediawiki are usually accepted. :) --Gmaxwell 14:47, 20 February 2006 (UTC)
thread_title:  Respect the originals 

message: For cases of non-photographic images using JPEG compression, I have created a template to place on the image page, .  It suggests replacing the JPEG image with a PNG or SVG image and refers the reader to Wikipedia:Preparing images for upload.  It has a corresponding category, :Category:Images with inappropriate JPEG compression, which is under :Category:Images for cleanup.  Please use as you find appropriate.  --ChrisRuvolo (t) 14:33, 2 December 2005 (UTC)
replies: text: Why Do all the templates I come across say to Upload as a new file and mark the privious file as redundant.  Why not just Upload a new version of this file.  I haven't done this yet so i'm probaly missing someting important.--E-Bod 23:51, 20 March 2006 (UTC)
replies: text: Because "a new version of this file" will still be a JPEG.  The whole point of this template is to replace JPEGs with PNG and SVG images.  --ChrisRuvolo (t) 12:49, 21 March 2006 (UTC)
replies: text: Thanks.  That Explains it for the Template for Images to convert to SVG and Images with inappropriate JPEG compression but what about for Category:Images with opaque backgrounds where most the images are already in PNG --E-Bod 22:24, 21 March 2006 (UTC)
replies: text:  asks for a PNG or SVG image.  It does not specify whether the source image is PNG or JPEG or GIF.  There may be a change in filetype because of this.  If not, obviously a new version of the same filename would be preferred.  If you want to edit the template to specify all this, go right ahead. --ChrisRuvolo (t) 22:43, 21 March 2006 (UTC)
thread_title:  Inappropriate use of JPEG 

message: Compare :Image:Star of life.gif and .  The underlying image in the latter is 5.76 KB, and the displayed PNG at full size is 15.37 KB.  By contrast, the GIF (and we're talking a GIF, which could be further compressed into a PNG) is 3.81 KB.
Now, I realize that the SVG can be more easily scaled up.  But is anyone seriously planning on scaling up a roughly 200×200 pixel image?  I also realize that it's theoretically easier to edit, but in practice, surely most people would find it easier to use a graphics program.  Finally, I realize that the size disparity would probably be reversed if SVGZ were fully supported by mainstream browsers, but that's probably not happening for another two years or so.
So I see two logical possibilities.  Either there was a problem in converting the specific file to SVG that resulted in an excessively large file size, and this problem is aberrant and/or can be corrected; or we should stick with plain PNGs for now where scaling isn't useful and the SVG filesize is greater.  Am I missing something? —Simetrical (talk • contribs) 01:46, 20 February 2006 (UTC)
replies: text: SVG isn't supported by mainstream browsers, and everything that supports SVG supports SVGZ (I'd welcome a counterexample...).  But all that is irrelvent: We don't send the SVG to the browser at all, it's rasterized into PNG on the server where size doesn't matter much. The PNG the server rasterizes should be roughly the same size as the PNG you rasterized. The ability to edit and the ability to use the image for more purposes is important.--Gmaxwell 14:41, 20 February 2006 (UTC)
replies: text: "The PNG the server rasterizes should be roughly the same size as the PNG you rasterized." maybe so but a carefully produced png with the same content optimised for the display size will be much much smaller, this is related to the thumbnail colors issue mentioned higher up, to get an optimal png at a specified pixel size requires a human who can make quality/size judgements. Plugwash 21:22, 26 October 2006 (UTC)

text: "We don't send the SVG to the browser at all, it's rasterized into PNG on the server where size doesn't matter much." Then why do these SVG images take up all my system memory when I click on them? In my experience with this format, it is garbage for use on the web, and the fact that you goons are actually replacing PNGs with them makes me want to choke babies. PNG is optimized precisely for what it's used for. SVG, regardless of your fetish with it, is crap for this purpose. Ditch it. New doesn't equal better. --76.224.90.253 04:28, 25 September 2007 (UTC)
thread_title:  Why SVG over PNG? 

message: I noticed Category:Images with opaque backgrounds.  Could sombody point me to where the value of Transparency in an image is prefered.  and as a side thought why all the templates in Images for cleanup all say to creat a reduntant page and fix it instead of simply updating a newer verthion of the file.--E-Bod 03:17, 19 March 2006 (UTC)
replies: text: The background of Wikipedia's articles is not always white.  Some images have unused portions (such as seals or insignias or logos).  To have the image look correct on all backgrounds it should be transparent.  --ChrisRuvolo (t) 23:07, 21 March 2006 (UTC)
replies: text: Ok, but what about when you want to print a page.  For example the image on Bucklin_voting#An_example when it prints (on paper not screen), the transparent part prints black and the image look awful on paper.  I was thinking of changing a few images with opaque backgrounds but I don't notice a problem on a typical view of the image and making the background transparent will make it print funny.  Is it my printer settings?  I am using a Canon i860.  If this would be valuables to include in the article I could submit a screenshot of the printing problem to illustrate the point if we chose to include this in the article.  Should we make a section in this page to advise about transparent opaque backgrounds?  I don’ want spend my time figuring out how to make the images have a transparent if it would just degrade form the articles they are in.--E-Bod 04:15, 1 April 2006 (UTC)
replies: text: I just Discovered The Printable version so mabe i should sugest a fix somewhere else--E-Bod 00:33, 4 April 2006 (UTC)
replies: text: I don't know where to sugest the fix though--E-Bod 21:23, 12 April 2006 (UTC)

text: Except that it doesn't look correct if you do as the template suggests, because IE 6 messes up when displaying images with alpha channels. While it might be nice to have images in that format, is it really a good idea to upload images that won't look right for the majority of our users? I like alpha-blended PNG as much as the next guy, but that doesn't mean it's the right thing to use if we want things to display as intended. GreenReaper 19:26, 18 April 2006 (UTC)
replies: text: If you set the background color on the image correctly IE6 shouldn't look too bad. PNGs with alpha are widely used on Wikipedia, it's a given that we've mostly given up on IE6 looking perfectly.  Wikipedia is in it for the long run... our content will most likely outlive some broken version of IE by such a huge margin it isn't even worth discussing. --Gmaxwell 21:50, 18 April 2006 (UTC)
replies: text: How do you properly print a page with an image with a transparent background so that the background isn't printed black.  I use Firefox but an explanation for IE would also be helpful.  Since a page is Blank I would like to be able to print the images as if the background is white.--E-Bod 20:45, 24 April 2006 (UTC)
thread_title:  Category:Images with opaque backgrounds 

message: I created this map :Image:First century palestine.gif using Illustrator CS2. I was asked to convert it to SVG and also to upload it on the commons. SO I reopened my illustrator file and saved it as an SVG from the "Save as..." menu option. I then uploaded that file here :Image:Iudaea province.svg, but as you can see something has gone array. I thought initially it may had to do with the clipping mask I used to crop the image, so I released that and uploaded another version, but still the same. As you can see Iudaea Province, there is an error: "Error creating thumbnail". Does anyone know what is wrong? Any advice on how to properly save a SVG for upload? Thanks!--Andrew c 14:45, 12 April 2006 (UTC)
replies: text: Ok, I figured out one problem. I had a crop area as well. Once I released the crop area, I could save the file and upload it and get the image to show. However, now I need to figure out how to make a crop area without using a crop area.--Andrew c 14:58, 12 April 2006 (UTC)
replies: text: Hmm... that didn't fix it. Well, I had one file version work. If you look at the file history, it is the 14:54 revision. I'm totally confused now. The only thing I did to the revision that worked, was deleted some anchor points that extended outside of the document page in order to get square borders (the reason I was originally using a crop area and a clipping mask). I thought it was releasing these things that made that one version work. But maybe that is not the case, because the latest upload doesn't work. I am totally confused now.--Andrew c 15:29, 12 April 2006 (UTC)
replies: text: I haven't touched anything since the last edit, but now it seems to be working, although the image on the Image: page looks terrible (the thumbnail on the article Iudaea Province looks fine though). Maybe it had something to do with my browser (Opera) because I am at work and firefox and IE show it fine. Totally confused still.--Andrew c 01:31, 13 April 2006 (UTC)
thread_title:  Coverting Illustrator file to SVG 

message: I'm a little confused, but I'm just starting out with SVG files so maybe that's understandable. 
I know that SVG files are converted by the server/software to PNGs before they display them inline; but are we supposed to see pixelation when we scale up an SVG file inline? For example, 
 (inline) shows distinct pixelation that doesn't exist on :Image:Benbrook flag.svg. What am I doing wrong? Or do SVGs also "autoresize" on the image page once you get to a certain native size, like very large JPG files do, where you get the Download high resolution version (1600x1200)? -- nae'blis 22:21, 13 September 2006 (UTC)
replies: text: Looks like a size (width, height) limit was put on PNGs generated from SVGs.  Maybe to prevent people from abusing the sever with .  I think the ideal size for an SVG would depend on how detailed it is. --Pmsyyz 01:25, 27 October 2006 (UTC)
thread_title:  Upload SVG files at what native size? 

message: I've uploaded a newer version of  but the generated PNGs (how it displays on any pages that don't render it to size that hasn't previously been displayed) all still look like the old version. Is there some way to force an update or something? Leland McInnes 17:39, 4 November 2006 (UTC)
replies: text: Go to the image description page (:Image:Co2-temperature-plot.svg) and in the address bar add
 ?action=purge
to the end of it. Got that info from WP:PURGE. --WikiSlasher 07:28, 5 November 2006 (UTC)
thread_title:  Updating PNG rasterization 

message: There is another quite an unknown software called DeflOpt that can squeeze some bytes out of PNGs compressed by OptiPNG, advpng, advdef and PNGOUT. It's current version is 2.04. I have been using it for some weeks now without problems. It is run on Windows using the command line interface. It can be downloaded from http://www.walbeehm.com/download/. --Hautala 21:08, 22 February 2007 (UTC)
thread_title:  DeflOpt and defluff 

message: (I looked around and couldn't find a direct answer to this question, so I figured I would ask it here.)
What should I do about whitespace on the edge of diagrams? For example, I just vectorized this image into this one. As you can see, in the original diagram there's some space around the outside edge, while on my version there is none. In terms of image-creation guidelines, is this ideal? Or should I have left a little whitespace ("transparentspace") around the edge? Check the article it's on to see how it looks on the page. Thanks!  MithrandirMage  T  06:50, 20 March 2007 (UTC)
replies: text: It would be a good idea to leave a little whitespace around the edges, like the raster copy has. —Remember the dot (talk) 04:54, 25 March 2007 (UTC)
thread_title:  Image framing 

message: thumb|50pxCan anybody help me to improve my photo  of tenrec (Lesser Hedgehog Tenrec - Echinops telfairi)? Pinky sl 08:06, 30 May 2007 (UTC)
replies: text: Nice Picture.  The Wikipedia Graphics Lab would probably be the best place to try for something like this. CountingPine 14:04, 30 May 2007 (UTC)
thread_title: Sharpening an image

message: I support Wikipædia 100% for their philosophy of using the right media type for the right data type (ie SVG for line drawings). However, I don’t think we go far enough, and I think it would be better if we finished the job we have started. In other words, I think it would be better if the pages that use a certain image used the actual SVG source image itself, inline, as opposed to simply a bitmapped PNG version of it (which more or less defeats the point of it in the first place)
So what I am proposing is that SVG images are embedded into articles using <object> or whatever (with a bitmapped fallback for older software), rather than using <img>. Not only would this speed up loading times and reduce bandwidth, and all the other used benefits of vector images, but it would also increase the adoption of W3-standard browsers in the world at large, and would also encourage Internet Explorer users to upgrade to something more compliant (and maybe it would also encourage Microsoft to improve their browser with full native support for this established format).
So how do we go about implementing this in the templates?
--- Different Author ---
When showing a mathematical plot (in whatever image format the uploader uses) it would be great if they included the formula or source code (IE: Matlab, GNUPlot, LaTex) used to produce the image. This allows corrections to be made in the event that there is an error in the plot.
The source code could be used by the reader (on thier own computer, without uploading the change) in the event that:
1. The reader desires to scale the image to view the finest possible details.
2. The reader chooses to remove some of the plotted lines when viewed so there is less clutter or better scaling of the desired portion.
3. The reader is colour-blind and desires to change some of the colours chosen by the author.
An example of where this would be useful is on this page: http://en.wikipedia.org/wiki/Window_function#Comparison_of_windows where there is a plot of over a dozen window functions on a small graphic (even when the larger image is viewed one may desire to remove some of the lines).  —Preceding unsigned comment added by 24.85.104.61 (talk) 15:22, 20 May 2008 (UTC)
thread_title:  Using the original SVG inline on the page 

message: Can anyone help with :Image:Arbans page 22 chromatic study.png? Wikimedia states: "Error creating thumbnail: Invalid thumbnail parameters." If you download the full resolution image you will see that there are no problems with the PNG file. For some reason the JPEG version works fine (:Image:Arbans page 22 chromatic study.jpg). I've had problems with the Wikimedia image rendering before but don't know where to ask for help or report bugs/issues.--Dbolton 19:56, 25 July 2007 (UTC)
replies: text: The problem seems to be common with two-coloured (one bit for colour) images. See for example . A work-around could be forcing the file to be saved in 4-bit or 8-bit palette. --Hautala 21:05, 25 July 2007 (UTC)
replies: text: There appears to be a memory limit that is reached by large (pixel-size) images. I reduced the image size by 50% and it fixed the problem--Dbolton 22:20, 25 July 2007 (UTC)
thread_title:  Problems with Wikimedia recognizing PNG image 

message: Are we allowed to use flash (.swf) files on wikipedia? If not, why? They could relly help explain things more.  —Preceding unsigned comment added by Theconster (talk • contribs) 23:28, 21 February 2008 (UTC)
thread_title:  Flash 

message: In the section where we say svg is the preferred image format for diagrams we recommend scribus, we should probably also mention inkscape, as I know most people prefer it. Also if we provide more options hopefully more people will actually start sending us in svg's. Joshua.leahy (talk) 19:20, 3 November 2009 (UTC)
thread_title:  Mention inkscape? 

message: Under a new top level heading "General concerns" a second level heading "Text" should be created, with the following advice:
:The placement of text in images should be limited or avoided, instead placed in the image caption, per Wikipedia:How to create graphs for Wikipedia articles#Guidelines (#3) and Wikipedia:Image use policy#Rules of thumb (#5).
Hyacinth (talk) 23:57, 11 April 2010 (UTC)
thread_title: Text

message: This is my first attempt to upload an image of my own creation. I stumbled onto this page so now I know to use SVG. However I expected this page to have a See Also link to the next step. § Music Sorter § (talk) 16:28, 16 June 2010 (UTC)
thread_title:  Page needs a link to how or where you actually upload the image 

message: I saw Commons template :Commons:Template:Opaque links to Wikipedia:Preparing images for upload but that page does not mention it. 
One, should we add some brief explanation and a link back to Commons in the see also?
Two, and I'm expecting my edit to be mercilessly reworked, but hopefully not blindly reverted, I have added this to the Commons template to suggest making a derivative in cases where a better original is unavailable. My intention is to avoid editors downloading the Commons image, modifying it to remove the background and then uploading a new (PNG or SVG) image and then deleting the original. In the case where no better original image is available I cannot see why deletion is a good idea. An example is :File:Mustafafazl.jpg. -84user (talk) 15:01, 17 June 2010 (UTC)
thread_title:  Opaque links and changes 

message: It seems that some uploaded images are produced from screenshots with subpixel rendering (I don't believe that any sane software can export such images). Here is one example: :File:BeethovenSymphonyNo5Mvt1SecondTheme.png. There are two concerns about it:
# Subpixel rendring must match the display type, and thus can look quite ugly if it does not match (rotated screens or printers are just two common examples).
# It is not intended for scaling, so its resampling can produce noticeable color artifacts.
Therefore, it might be appropriate to warn against using subpixel rendering in the images and to advise turning it off before taking screenshots (if the screenshots are unavoidable).
I don't know how many such images are uploaded, so I'm not sure whether a category to mark them needs to be created...
Mikhail Ryazanov (talk) 04:22, 6 February 2011 (UTC)
thread_title:  Subpixel rendering 

message: I tried to upload a plot in EPS format, and it was rejected due to the file format.  I created the plot using IDL, which uses PostScript as its default graphics output format.  This document should contain instructions on how to convert a PostScript plot into SVG format.  --BlueMoonlet (t/c) 19:55, 2 December 2013 (UTC)
thread_title:  WP won't accept EPS 

message: *This page has barely been edited in five years, despite changes to MediaWiki and common practice since then (maximum upload sizes are now 1 gigabyte, SVG is no longer used for just simple images (example), and as mentioned above file size is barely a consideration). Perchance there is someone interested in updating this page? — Crisco 1492 (talk) 14:53, 23 January 2015 (UTC)
thread_title: Out of date?