identify -format fails

[Drarakel]

It seems, that an "identify -format %A" alone (for checking whether there's an alpha channel) doesn't read the image anymore correctly?

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convert logo: -transparent white logo.png
identify -format "%A" logo.png

False

The above worked in older IM versions, but not with the current version.
However, when combined with other properties, it's ok:

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identify -format "%A\n%r" logo.png

True
DirectClassRGBMatte

(By the way, it should be PseudoClass here, not DirectClass.)
Using ImagMagick v6.6.7-10 Q16, Windows XP.

[magick]

We can reproduce the problem you posted and have a patch in ImageMagick 6.6.8-0 Beta (available by sometime tomorrow). Thanks.

[Drarakel]

Works now. Thanks!

[Drarakel]

Another small thing.. 'identify -format "%x %y"' sometimes fails, too - at least with PNG files. Example - take this file:
http://img651.imageshack.us/img651/5595/rosebc.png

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identify -verbose rosebc.png

...
Resolution: 456x456
Units: PixelsPerInch
...

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identify -format "%[xresolution]x%[yresolution]" rosebc.png

456x456
But with the next command, only the IM default value gets reported:

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identify -format "%x x %y" rosebc.png

72 Undefined x 72 Undefined
But it works with "+ping":

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identify +ping -format "%x x %y" rosebc.png

456 PixelsPerInch x 456 PixelsPerInch
Or without +ping, but with an additional 'property':

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identify -format "%x x %y\n%[version]" rosebc.png

456 PixelsPerInch x 456 PixelsPerInch
ImageMagick 6.6.8-2 2011-03-06 Q16 http://www.imagemagick.org

Seems that all of the tEXt/zTXt chunks in PNG are affected.

[glennrp]

Yes, a recent patch involving the PNG text:density chunk inadvertently
suppressed all of the text chunks. Should be OK now in IM-6.6.8-4, SVN r3845.

[glennrp]

How was the file "rosebc.png" created? It contains a text:density chunk and a text:units chunk,
and is missing some of the chunks usually written by ImageMagick.

[Drarakel]

I created the chunks manually (with TweakPNG).
Thanks for the new patch!