UIImage Conversion Sample

Paul Solt 2010

Here's a sample project and code to convert between UIImage objects and RGBA8 bitmaps. The sample project is iPhone 4/iPad 3.2 compatible.

The ImageHelper works with iPhone 4 and the Retina display using the correct scale factor with high resolution images.

Basic Example Usage showing the ability to convert back and forth between formats:

// Look at the sample project for actual usage

NSString *path = (NSString*)[[NSBundle mainBundle] pathForResource:@"Icon4" ofType:@"png"];
UIImage *image = [UIImage imageWithContentsOfFile:path]; 
int width = image.size.width;
int height = image.size.height;

// Create a bitmap
unsigned char *bitmap = [ImageHelper convertUIImageToBitmapRGBA8:image];

// Create a UIImage using the bitmap
UIImage *imageCopy = [ImageHelper convertBitmapRGBA8ToUIImage:bitmap withWidth:width withHeight:height];

// Display the image copy on the GUI
UIImageView *imageView = [[UIImageView alloc] initWithImage:imageCopy];

// Cleanup
free(bitmap);