#2226 Non-idential image files reported as identical

[Gitoffthelawn]

WinMerge v2.16.2 reports non-identical image files as identical when the image itself is the same, but other data within the file is different.

I noticed this when comparing 2 jpg files. The images contained in the jpg files were the same, but a binary compare revealed that the files were not identical.

To me, it's important that the term "identical" only be used if the two files are exactly bitwise equal. Perhaps, in the case of image comparisons when the files appear identical, perform a binary comparison and report that result.

[Gitoffthelawn]

I apologize for the typo in the report title. Noticed it as soon as I posted it, and see no way to edit.

[Georg D]

+1 for changing image comparision because current implementation can easily lead to accidental data loss.

My case: I was confused that comparing 2 directories in Altap Salamander told picture files differ but WinMerge 2.16.4.0 told "The selected files are identical". It took me a while to figure out using WinMerge > menu bar > File > Recompare as > Text that the meta data section differs (e.g. XMP rating oder EXIF geo position) while the JPG's picture content is identical.

Idea for short quick measure: Re-word existing message text "The selected files are identical" to "The selected files have identical picture content but may differ in meta data. To check this, use recompare as > binary . so effort is very low but users know better how to interpret the message and how to do a "complete" comparision.

Idea for long term measure: First, do binary compare of the picture files. If identical, tell "The selected files are binary identical". If they differ, do current picture content comparision and depending on the result tell "The selected files have identical picture content but other data differs." respectively show the picture differences.