How to tell an 8-bit indexed PNG from a 24 bit RGB PNG

[goofy166]

Is there a way to use ImageMagick from the command line to determine the bit depth of a PNG?
I am using Photoshop to do this and it seems to give me contradictory results. Specifically I am using the Photoshop File->File Info menu.

Thanks

Mitch

[snibgo]

Is there a way to use ImageMagick from the command line to determine the bit depth of a PNG?

IM isn't designed to tell you anything about the contents of a file. exiftool is designed to do that.

[goofy166]

OH thanks I really appreciate this answer. I will download it. I am not a command line jock and on a Mac. Do you happen to know the terms I need to feed exiftool to get it to tell me the file details?

Mitch

[snibgo]

Once you've downloaded exiftool:

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exiftool myfile.png

Look out for:

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Bit Depth                       : 8
Color Type                      : Palette

... or ...

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Bit Depth                       : 16
Color Type                      : RGB