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Identify fails with MNG images

Posted: 2010-07-14T11:10:00-07:00
by Drarakel
The MNG output itself seems to be alright, but identify has problems:

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convert -depth 8 xc:blue MNG:test.mng
identify test.mng
Magick: corrupt image `test.mng' @ error/png.c/ReadMNGImage/4105.

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convert -depth 8 -size 100x100 xc:blue MNG:test2.mng
identify test2.mng
Magick: memory allocation failed `test2.mng' @ error/png.c/ReadMNGImage/4112.

Only "identify +ping" (or "identify -verbose") has no problems in reading these files:

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identify +ping test2.mng
test2.mng MNG 100x100 100x100+0+0 8-bit DirectClass 481B 0.000u 0:00.000

I'm using ImageMagick v6.6.3-0 Q16, on Windows XP.


Edit:
By the way: When creating animated MNGs, "identify -verbose" always shows an alpha layer - even when there's no alpha at all in the individual images (provided that TweakPNG shows correct values for such files). But as I'm using MNG not much, I'm not sure how it's supposed to be.

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convert -delay 100 -depth 8 -size 100x100 xc:blue xc:red MNG:bluered.mng
identify -verbose bluered.mng[0]
...
Alpha:
min: 255 (1)
max: 255 (1)
mean: 255 (1)
standard deviation: 0 (0)
kurtosis: 0
skewness: 0
...


Edit2:
Another small issue with MNG:

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convert rose: logo: +adjoin images.mng
Magick: input has zero delay between all frames; assuming 10 cs `' @ error/png.c/WriteMNGImage/9203.

The files (images-0.mng and images-1.mng) are ok, but the error message is confusing. :) Especially since this works without error message:

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convert logo: logo.png
convert rose: logo.png +adjoin images.mng

Re: Identify fails with MNG images

Posted: 2010-07-29T00:40:37-07:00
by Drarakel
The 'main problem' here - the error messages from identify - got solved now in version 6.6.3-1. Thank you!

Re: Identify fails with MNG images

Posted: 2010-08-01T16:37:50-07:00
by Drarakel
The 'zero delay' error message is gone, too. Thanks again!