Re^3: Perl GD problem with colors for text

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.

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Re^4: Perl GD problem with colors for text by natol44 (Sexton) on Nov 28, 2009 at 08:23 UTC
Thank you for your time! I converted into GIF and yes, it works, on this picture. Using other pictures, if I try to print text in another color in the same line (2 colors on the same line), again it bugs. $red = $im->colorAllocate(255,0,0); $green = $im->colorAllocate(0,255,0); $im->string(gdSmallFont,555,6,$testline1,$red); $im->string(gdSmallFont,628,6,$testline2,$green); A new pic has been uploaded at http://www.2shared.com/file/9508604/28e97b03/lr1_fee.html The Green shows in "white"... Moreover working in GIF makes strange things in the pics that show up with defects in my application. I wonder if there isn't a way to make it work in PNG? After all GD is supposed to support PNG too... Thank you	[reply]
Re^4: Perl GD problem with colors for text by gmargo (Hermit) on Nov 28, 2009 at 08:00 UTC
I had success with the `newFromJpeg` constructor, with the `$truecolor` flag set to 1. `my $im = GD::Image->newFromJpeg( $jpg, 1 );` [download] It was quite educational to run the `identify -verbose` command (from the `ImageMagick` suite) on the "before" and "after" images.	[reply] [d/l] [select]