ios - How to remove the transparent area of an UIImageView after masking? -

ios - How to remove the transparent area of an UIImageView after masking? -

in 1 of ios applications, trying cutting portion of image using cgimagemask. have succeeded in masking image next code:

- (uiimage *)maskimage:(uiimage *)referenceimage withmask:(uiimage *)maskimage { cgimageref maskref = maskimage.cgimage; cgimageref mask = cgimagemaskcreate(cgimagegetwidth(maskref), cgimagegetheight(maskref), cgimagegetbitspercomponent(maskref), cgimagegetbitsperpixel(maskref), cgimagegetbytesperrow(maskref), cgimagegetdataprovider(maskref), null, false); cgimageref masked = cgimagecreatewithmask([referenceimage cgimage], mask); homecoming [uiimage imagewithcgimage:masked]; }

so, image be:

myimageview.image = [self maskimage:[uiimage imagenamed:@"image.png"] withmask:[uiimage imagenamed:@"mask.png"]];

problem: output image of same size of reference image('image.png') transparent area around. want avoid transparent area, , crop result image. how can accomplish this? there several masks, , mask frames not similar all. attaching reference image of problem overview here. please help me friends. in advance.

look auto-cropping uiimage. should crop out transparent.

how autocrop uiimage?

ios objective-c core-graphics masking cgimagemaskcreate