The GD documentation for the colorAllocate function says:
If no colors are allocated, then this function returns -1.

Checking $mycolor, I found that it was set to -1 for all 2553 possible RGB combinations.

Assumption: Because the string function received -1 for the color value, it used the (first|last|?) value in the image's existing palette, thus explaining why the text appeared in the same color as the box.

I then converted test.jpg to test.gif with an image editor, and changed $jpg to "test.gif". $mycolor received a positive value, and the text appeared in the chosen color.

I then tried an explicit GD::Image->newFromJpeg on test.jpg, to no avail. I also tried converting to test.png, also to no avail.

It appears that colorAllocate works correctly when starting with .gif images, but not for .jpg or .png.

In reply to Re^3: Perl GD problem with colors for text by keszler
in thread Perl GD problem with colors for text by natol44

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