Bug #79287 [Opn]: imagewebp function quality parametter as no effect JPG only

Edit report at https://bugs.php.net/bug.php?id=79287&edit=1 ID: 79287 User updated by: pierre at lookit dot fr Reported by: pierre at lookit dot fr -Summary: imagewebp function quality parametter as no effect +Summary: imagewebp function quality parametter as no effect JPG only Status: Open Type: Bug Package: GD related Operating System: xubuntu 18.04.4 LTS PHP Version: 7.2.27 Block user comment: N Private report: N New Comment: After news tests, it seems that this bug affect only JPG images Previous Comments: ------------------------------------------------------------------------ [2020-02-19 16:20:37] pierre at lookit dot fr Description: ------------ When i change the quality parameter in the imagewebp function, the image returned is exactly the same. This parameter seems to have no effect on the conversion process. I've tested with jpeg and png images files. The file is well converted, but when i change the quality parameter to another value, nothing appear to change on image resulted. Test script: --------------- $destination = '1.webp'; $origine = '1.png'; @$webp = imagewebp(imagecreatefrompng($origine), $destination); $destination = '2.webp'; $origine = '2.jpg'; @$webp = imagewebp(imagecreatefromjpeg($origine), $destination); $destination = '3.webp'; $origine = '1.png'; @$webp = imagewebp(imagecreatefrompng($origine), $destination,50); $destination = '4.webp'; $origine = '2.jpg'; @$webp = imagewebp(imagecreatefromjpeg($origine), $destination, 50); //Ok after that i open results in photoshop for a deeper analyse on change....but nothing appear to have changed !!! ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=79287&edit=1