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what image format is best for face recognition

asked 2016-10-05 09:08:08 -0500

atv gravatar image

I read somewhere on the forum that jpeg's should be avoided. Why is that and what file format would suit it best instead. PNG ?

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answered 2016-10-05 10:58:16 -0500

berak gravatar image

png is probably your best choice (non-lossy, still allows some compression) .

jpg's should be avoided for 2 reasons here:

  • lossy compression. you won't get exactly the same pixels on a different machine or a with a different program.
  • compression artefacts. jpg processes 8x8 pixels patches, which leaves a border, almost invisible to the human eye, but if you try LBPH face-reco on this, you get clear artefacts (edges) that get in your way.
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Thanks berak. Certainly helpful. Do these artifacts appear with fisherfaces as well? I'll have a go tonight and see if it makes any difference there.

atv gravatar imageatv ( 2016-10-05 11:53:34 -0500 )edit
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The artefacts generated by jpeg compression screw up almost every decent computer vision algorithm depending on local gradients or pixel intensities. So yes, also fisherfaces will be influenced!

StevenPuttemans gravatar imageStevenPuttemans ( 2016-10-07 03:19:31 -0500 )edit
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That's awesome, thanks for your comment Steven.

atv gravatar imageatv ( 2016-10-07 05:25:14 -0500 )edit

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Asked: 2016-10-05 09:08:08 -0500

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Last updated: Oct 05 '16