Do you need mean this?

$image = GD::Image->newFromJpegData($data, $truecolor) These methods will create an image from a JPEG file. They work just like newFromPng() and newFromPngData(), and will accept the same filehandle and pathname arguments. The optional $truecolor (0/1) value can be used to override the global setting of trueColor() to specify if the return image should be palette-based or truecolor. Bear in mind that JPEG is a 24-bit format, while GD is 8-bit. This means that photographic images will become posterized.

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