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Does Flickr recompress JPEGs after upload? I know that if you upload a TIFF, for example, Flickr converts it to JPEG. But do they also compress incoming JPEGs?

I've read some complaints about the quality of the JPEG compression used on Flickr. I'm just wondering if it makes sense to upload TIFFs and let Flickr to the conversion or to upload a high quality JPEG in the hopes that Flickr doesn't recompress it.

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3 Answers

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If you upload a JPEG, Flickr does not modify the Original-size image in any way (apart from changing the filename), at least not on a Pro account.

I tested it out by uploading a full-size, 100% quality JPEG to Flickr then re-downloading the Original size image and comparing it with the original (using a comparison tool called Beyond Compare). The two files are identical, byte for byte. That means not only has the image not been compressed but all the original metadata (Exif etc.) is also intact.

I'm on a Pro account so I can't be sure about Basic accounts but my guess is that the same applies, they just restrict you from viewing it.

I also tested a TIFF and the Original image on Flickr is a JPEG. So in the case of TIFFs, they are compressed. (All JPEGs are compressed so some extent, even if you choose 100% quality - hence the size difference between JPEG and an equivalent TIFF.)

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Cool. Good way to confirm the original JPEG remains the same. Thanks! I guess the last remaining question would be how much compression they use on TIFFs when they make them JPEGs. Is it worth the extra step making a 100% quality JPEG on my end before uploading? – jaxxon May 27 '11 at 4:06
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same for GIF files btw. They aren't changed too. But previews will be in jpg. Important for animated gif files. – Dr.Elch May 27 '11 at 4:29
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From the flickr FAQ: "We resize your photos to more web-friendly dimensions. Each image has a 75x75 pixel thumbnail and 100-, 240-, 500-, 640- and 1024-pixel versions (that's the length of the longest side), as well as your original file. ... If you have a free account, no one (including you) can access your original file. ..." http://www.flickr.com/help/photos/#89

So I would say they are processing all uploaded files, so the files fit their needs for the presentation on flickr (dimension, file size, compression-quality, dpi ...), and keep the original as is.

As I do not use TIFF (but RAW), I can not say if it is worth to upload a TIFF in regard of final image quality on flickr, but I doubt it. However it is sure worth for one good reason: backup :)

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Sounds about right. Thanks. – jaxxon May 26 '11 at 6:34
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The original sized jpg on flickr afaik will be the original file you uploaded with no compression (which would have to be converted to kpg if you upload as a TIF) but the smaller sizes will be compressed to some degree as they're resized jpgs. This shouldn't make too much difference as people can view the full sized image if they want to see that much detail. This is assuming you have a pro account to be able to view the original sizes

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Thanks. I've had a pro account since 2005. This has been my assumption as well. But that is all - an assumption. Nowhere on Flickr nor in their forums have I found an answer. – jaxxon May 26 '11 at 6:02

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