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0 pointsem-bee5y ago0 comments

they probably have different metadata. if you convert all of them to png, do they still differ?

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3 comments · 2 top-level

yjftsjthsd-h5y ago· 1 in thread

There are already 2 pngs in that list, and they already have different md5s

that could be caused by different compression levels or other artifacts in the metadata.

my expectation was that in the conversion, metadata and possible artifacts that stem from different tools used to create the image would be normalized.

in the sister reply diggernet choose even better formats than png as conversion targets, and answers the original question in this subthread

diggernet5y ago

Interestingly, if they are all* converted to ppm, only iii and ix are the same. Only part of the difference is comments. There are also differences in value encodings.

Also, if converted to bmp, only ii and vi are the same.

Edit: Converted to xpm, all are different. (When the embedded filenames are reconciled, ii and vi are again the same, the rest differ.)

*Except v.gif, which is invalid.

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