04-21-2010, 06:40 AM

Hi, I'm a new user and I'm moving the firsts steps into Objective C. I want to apply some filters (CIFilters) to an image (CIImage) that is contained into a mImageView (IKImageView). How can I do that?

My crazy mind thought to this:


NSArray *filters = nil;
CIFilter *filter = [CIFilter filterWithName:@"CIBloom"];
[filter setDefaults];
[filter setValue: [NSNumber numberWithFloat:2.0] forKey:@"inputRadius"];
filters = [NSArray arrayWithObject:filter];

CIImage *image; // in this line I don't know what to write...I put it, to intend that I declared a CIImage object
image = [filters valueForKey: @"outputImage"];



But unfortunately it doesn't work....can you help me?

Best Regards

Manu

04-21-2010, 05:52 PM

I know almost nothing regarding CIImage, but you are at minimum missing;

[filter setValue: aSourceCIImage forKey:@"inputImage"];

aSourceCIImage being the input image you are trying to manipulate. Other image types have to first be converted to a CIImage type for use in the filter.

I'm not sure what your intent is for the array, but that array will only hold one object since it is not a NSMutableArray.

If you are thinking of chaining multiple filters, I don't think you need an array. As I understand it, you use the output of the previous filter as the input to the next filter. The system will take care of optimizing all of the built up filters.

At the end of the code, you need a way to turn a CIImage into something displayable.

I would look at the Apple documentation and review the samples they link to.

05-26-2010, 01:02 PM

Did you manage to get any further with this?

For the line:

CIImage *image; // in this line I don't know what to write...I put it, to intend that I declared a CIImage object

You can create a new CIImage using:

[CIImage imageWithContentsOfUrl: NSURL * fileURL];

There are many other constructors for the CIImage class too.