How to add Bump filter effect on UIImage in iphone SDk. I am trying to implement using kernel values and convolve effect, but it gives very huge bump effect i need some small bump effect on image.
If you are targeting 5.1 and later you can find it in Core Image if you need to deploy to lower target you can use the awesome GPUImage framework from Brad.
Check this SO question to have more details about both.
I am trying to extract the outline of UIImage for one of my application . The requirement is that ,i want to process the actual uiimage and extract the outline for painting as mentioned in the below picture. I found a solution that, we can implement this with imagemagick apis.
I am not sure whether any API is available in Iphone SDK for doing this.If not how can i implement this using imagemagick apis,(communication between C language in imagemagick and Objective C)
Thanks in advance...
Is there a way to apply some functions like:brightness,contrast,sharpness,hue,saturation,exposure to uiimages. For example I have a UIImageview and inside that i have a uiimage. I want to manipulate its brightness or contrast or sharpness with a help of UISlider
Have a look at the sample app GLImageProcessing, however it uses openGL to do the image processing, but it is really fast.
In my application I have a color video which I want to make as black and white video. Is there any framework that supports this in iOS? If so, how to implement that effect on color video?
Can anyone help in this regard?
A bit late here, but you should check out OpenCV.
It can be compiled as a static lib for the iPhone and can convert video (frame by frame) to grayscale or two color.
You can start here. There are other resources for doing this floating around.
HI Lakshmi this might be familiar to you that at least 24 frames make a clip of video so you have to use a tool like movie maker so that you can see the video frame by frame and edit each frame.
See the opensource Framework named: GPUImage https://github.com/BradLarson/GPUImage/
The filter name GPUImageGrayscaleFilter is what you want
This framework included the sample code, so you can learn how to use GPUImageGrayscaleFilter in your apps easily
I've run into the issue of using a UIBarButtonItem with a custom color. Everything out on the 'net seems to indicate that the only way around this lack of official API support revolves around the use of images. This is all fine and dandy when developing for pre-iOS 4 devices, except when using the new iPhone 4. Creating an image for iPad and pre-iOS 4 devices is straightforward enough, but the images developed for those devices look absolutely horrid on iPhone 4. I suspect that this problem will be exacerbated further with the introduction of next generation devices.
Consider the example below. Notice how the default colored button is nice and smooth, but the iPhone 3GS image looks terrible. It does not seem very scalable (pun intended) to have to include multiple images for different resolution devices.
In the absence of an official API for changing the color of a UIBarButtonItem, what strategies are out there for creating images that scale well against differing resolution devices? This problem is hardly unique to UIBarButtonItems, how is the community adapting to other UI elements that are bitmapped? Is there a better solution for this particular case than using an image (such as using Quartz to draw it)?
If at all possible, please offer concrete code examples.
You can list any image as Image#2x.png along with Image.png and the system will select the appropriate image at runtime.
If you look at the source for Three20 you can see how they draw custom buttons and shapes that will scale well, regardless of resolution.
Give Opacity (for Mac) a try. Draw your button in it with vector elements and effects, and it'll spit out the necessary Quartz code to reproduce it, drawing natively in your iOS application. You get Retina (#2x) support automatically.
Been over a year since I posted this question, but ran into a use case where I wanted to be able to do this, so instead of having to draw or otherwise create the buttons, I decided to write an open source application to create them. This application uses private APIs to change the colors of the UIBarButtonItem objects and then uses a graphics context to save them to a determined location on your computer's file system. This way you can have pixel perfect UIBarButtonItem images to use in your UIToolbars.
The app creates both the standard and #2x resolution images.
UIBarButtonItem-Generator # GitHub
Any vector drawing app may work, but I would also consider povray, which allows you to create in a C-like scripting 3D language, then export any pixel size you choose.
http://povray.org
I have the same problem with navigation bar so solve as the following:
first i subclass my navigation bar
inside this class
- (void)drawRect:(CGRect)rect
{
UIImage *image=[UIImage imageNamed:#"MyImage.png"];
self.frame=CGRectMake(0, 0, image.size.width, image.size.height);
self.backgroundImage =image;
}
finally save the same image with different resolution With #2x at the end