$ convert ejemplo_ori.png -morphology edgein diamond:1 -negate result_2.png
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Thank you SO MUCH! You save my day!
Ok! While I wait for others answers, I will try to downgrade.fmw42 wrote:6.7.7.10 was not a good version of IM. IM was undergoing some major changes. I would then agree that you should try a downgrade if you cannot upgrade.