How to compress image size using UIImagePNGRepresentation - iOS?

ios objective-c uiimage uiimagejpegrepresentation uiimagepngrepresentation
Hyder picture Hyder · Feb 11, 2016 · Viewed 7.1k times · Source

I'm using UIImagePNGRepresentation to save an image. The result image is of size 30+ KB and this is BIG in my case.

I tried using UIImageJPEGRepresentation and it allows to compress image, so image saves in < 5KB size, which is great, but saving it in JPEG gives it white background, which i don't want (my image is circular, so I need to save it with transparent background).

How can I compress image size, using UIImagePNGRepresentation?

Answer

Filip Radelic picture Filip Radelic · Feb 11, 2016

PNG uses lossless compression, that's why UIImagePNGRepresentation does not accept compressionQuality parameter like UIImageJPEGRepresentation does. You might get a bit smaller PNG file with different tools, but nothing like with JPEG.

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