Description:
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Perhaps more of a "Bundled GD" issue that an PHP issue 
directly - I'd love to have support for reading and 
writing "comments" from images (TEXT records in PNG, 
comments in JPEG).  EXIF support only covers reading 
information, not creating or editing records for images. 
 
Either ability to read and write 
"comments" (imagewritepngtext($image)?  
imagewritejpegcomment($image)?) or even just ability to 
create and write EXIF data in the EXIF functions would be 
nice. 

Reproduce code:
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(N/A)

Expected result:
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Ability to generate (for example) geotag information 
for .jpeg images, or for PNG-format map images generated 
in PHP. 

Actual result:
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(N/A - feature request for new functions)