Gamma Error Picture Scaling
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Consequences Solutions Send a mail to the authors of your software Use a correct software Use the software correctly Assume a gamma of 2.2 ImageMagick Gimp-gluas Use the plugin for the Gimp Cinepaint Fast calculations PHP Acknowledgments what is analytic cubism? Best Monitor till now to view this page was a standard CRT Dell M783c which of the following is not correct regarding the differences between the two images below quizlet Introduction There is/was an error in most photography scaling algorithms. All software tested (August 2007) had the problem: The Gimp, Adobe Photoshop, which of the following explains why some audiences were not accepting of cubism? CinePaint, Nip2, ImageMagick, GQview, Eye of Gnome, Paint and Krita. Also three different operating systems were used: Linux, Mac OS X and Windows. (Software that don't have the problem are listed in the Solutions chapter.)
What Is Gamma Correction
Photographs that have been scaled with these software have been degradated (see the examples). The degradation is often faint but probably most pictures contain at least an array where the degradation is clearly visible. I suppose this happens since the first versions of these software, maybe 20 years ago. Below, a photograph of His Holiness the Dalai Lama was tuned to exploit the problem. If you want to give it a try, scale it down 50% using your best software. (If you cannot download the image to your computer by right-clicking on it, then either make a snapshot of the screen or download the image in this zipped file.) This is what you probably will get once the image is scaled by your software: How much did you pay for that software? This is a scaling performed by a correct software, which evidently shows the same as the start image: If you would like to see how your browser scales the image, click here. To get a smoother image tuned for TFT displays, click here. If you'd like the routines I wrote to create the Dalai lama pictures: gamma_grayator.tar.gz When I showed him the examples below, a friend who is a photographer told me he had noticed that error since a long time and lots of his colleagues did. They never could word or understand it. It made them loose a lot of time and caused much frustration. What about the digital age preserving the information? My friend tells me that professional argentic scalings didn't cause such errors. He believes that the problem is mainly due to the fact that the teachers of photographic art in the academies do not understand this technical item. If th
most photography scaling algorithms. All softwares tested have the problem: The Gimp, Adobe Photoshop, CinePaint, Nip2, ImageMagick, GQview, Eye of Gnome, Paint and Krita. Also three different operating systems were used: Linux, Mac OS X, Windows. This means that photographs that have been scaled with these softwares have been degradated. The degradation is often faint but probably most pictures contain at least an array where the degradation is clearly visible. I suppose this happens since the first versions of these softwares, maybe 20 years ago. When I showed him the examples below, a friend who is a photographer told me he noticed that error since a long time and lots of his colleagues did. http://www.4p8.com/eric.brasseur/gamma.html They never could word or understand it. It made them loose a lot of time an caused much frustration. What about the digital age preserving the informations? My friend tells me that professional argentic scalings didn't endure such errors. Now he uses a scaling routine I wrote for him, in the waiting the main graphic softwares improve. Technically speaking, the problem is that the computations are performed as if the scale of http://mirror.yandex.ru/mirrors/ftp.flightgear.org/docs/www.4p8.com/eric.brasseur/gamma.html brightnesses was linear. While in fact it is an exponential scale. In mathematical terms: a gamma of 1.0 is assumed while it is 2.2. Lots of filters, plug-ins and scripts probably make the same error. Good news! Form version 10.20 on, the Netpbm toolkit for graphic manipulations contains the "pamscale" command that performs scalings correctly. Go to netpbm.sourceforge.net . Note pamscale will not scale correctly when using the -filter option. Examples The error appears clearly when scaling the clerid beetle picture available on Wikipedia. This first 1:4 scaling was done using The Gimp: While this, proper, scaling was done using a C++ routine I wrote: To best compare these two pictures you can either download them and switch between them using a viewer. Or you can click here. (The picture canvas was reduced from 1600x1067 to 1600x1064 before scaling.) Another example? To compare a wrong and a correct scaling of a photograph of the Kings Creek in the Lassen National Park click here. I removed the labels "correct scaling" and "incorrect scaling" from the pages so they won't distract the perception of the images while switching. I put the labels as windows titles. More simply: the brighter picture is the correct one. What about your holliday photographs? Next example was cropped out of the
/ 5D / 6D TalkChange forum Gamma error in picture scaling Started Feb 26, 2010 | Discussions Shop cameras & lenses ▾ Forum Threaded view Paul Stout • Contributing Member • Posts: 977 Gamma error in picture https://www.dpreview.com/forums/thread/2759232 scaling Feb 26, 2010 It appears that CS4 still has this problemhttp://www.4p8.com/eric.brasseur/gamma.html-- hide signature -- Photography on the Run http://www.pbase.com/paul42/renaissance_fairs more than eight million hits! Reply to thread Reply with quote Complain Forum Threaded view Keyboard shortcuts: FForum MMy threads Latest reviewsSigma 30mm F1.4 DC DN | C for Micro Four Thirds84%Nikon AF-S Nikkor 24mm F1.8G what is ED88%Olympus E-PL8 First Impressions ReviewYI M1 First Impressions ReviewPanasonic Lumix DMC-G85/G80 First Impressions ReviewSee all reviews » Finished challengesElephants Performing by TX Photo Docfrom Random Items - Challenge 29Choices by Frenchfxfrom A Fork in the RoadReady for the week by ackebousfrom Show us CLOTHING!Montreal Noir Photography 1984 DP by MarioSSfrom Noir photographyDiscover more challenges » Most popular camerasSony Cyber-shot which of the DSC-RX100 IV2.0%Canon EOS 5D Mark IV1.7%Panasonic Lumix DMC-LX1001.6%Fujifilm X100T1.3%Panasonic Lumix DMC-ZS100 (Lumix DMC-TZ100)1.3%Leica Q (Typ 116)1.3%Canon PowerShot G5 X1.2%Nikon Coolpix P9001.2%Sony Cyber-shot DSC-RX1R II1.2%Sony Cyber-shot DSC-RX100 III1.2%Other popular cameras » FeaturesIn-depth testingLatest Camera ReviewsBeyond the studio testsFeature Articles and Videosreal world performanceField Test Videossee how we seeSample Galleriesfield testShooting action with the Nikon D5152videoPhotokina 2016 wrap-up Top threads in this forum41What to expect from 6DII?171DX II owners, what made you finally jump?16Canon no longer services 1D Mark III - what to do now?5DoubtIbeg help: 5DIII vs. 6D2Questions on the 5d mark iv when shooting 1080p1Canon or Tamron 24-70mm for 5Ds?15DMKIV with 50mm 1.8ii VS 50mm 1.215D Mk4 corrupting cards Top posters in this forum26Dr_Jon20henrikbengtsson19LDunn115Redcrown14XeroJay14marshwader14J A C S13Rick Knepper12larry12Ashkanani12Robert Zanatta9David Burren9Iliah Borg9Sage9John Sheehy9Mystery Gardener9noms789tvstaff8Dan_1688RedFox88 www.dpreview.com Follow us Mobile site About About us Work for us Advertise with us FAQ Feedback Interest-Based Ads Privacy Legal Editorial content News Camera reviews Lens reviews Printer reviews Buying guides Sample images Videos Cameras & Lenses Cameras Lenses Camera search Camera comparison Lens search Product timeline Browse all products Community Forums
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