On iOS, Is there a way to get the size of an ImageContext after creating it using UIGraphicsBeginImageContextWithOptions?

Question

If an image context is created using:

UIGraphicsBeginImageContextWithOptions(CGSizeMake(768, 768), YES, 1.0);

is there a way to get the size of the context later on? The size for sure is there when the image is obtained from the context, but while drawing, is there also a way to get the width and size of it?

score 2 · Accepted Answer · answered May 28 '12 at 09:05

2

For a bitmap context as above you can use:

CGContextRef context = UIGraphicsGetCurrentContext();
size_t width = CGBitmapContextGetWidth(context);
size_t height = CGBitmapContextGetHeight(context);

answered May 28 '12 at 09:05

Simon Lawrence

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works with ImageContext... and I guess supposedly it won't work with a context that is a CGLayer of size (768, 768) – Jeremy L May 28 '12 at 09:47
(coz it would print out error even thought that CGLayer was created with a size (768, 768)) – Jeremy L May 29 '12 at 00:45
This exact code returns 0 for me (both for width and for height). I thought that's because the UIGraphicsGetCurrentContext doesn't return a bitmap context. – Noam Ohana Jul 28 '22 at 13:13

On iOS, Is there a way to get the size of an ImageContext after creating it using UIGraphicsBeginImageContextWithOptions?

1 Answers1