A UIImage category that renders one page of a PDF.

UIImage+Rob_PDFPage.h

#import <UIKit/UIKit.h>

@interface UIImage (Rob_PDFPage)

/**
    I return an image in which I have drawn page `pageNumber` of the PDF found at `url`.  Pages are numbered starting at 1.  If I can't draw the page, I return `nil`.
*/
+ (UIImage *)Rob_imageWithPDFURL:(NSURL *)url pageNumber:(size_t)pageNumber;

@end

UIImage+Rob_PDFPage.m

#import "UIImage+Rob_PDFPage.h"

@implementation UIImage (Rob_PDFPage)

+ (UIImage *)Rob_imageWithSize:(CGSize)size opaque:(BOOL)opaque scale:(CGFloat)scale block:(void (^)(CGContextRef gc))block {
    UIGraphicsBeginImageContextWithOptions(size, opaque, scale);
    block(UIGraphicsGetCurrentContext());
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return image;
}

+ (UIImage *)Rob_imageWithPDFPage:(CGPDFPageRef)page {
    if (!page)
        return nil;

    CGRect box = CGPDFPageGetBoxRect(page, kCGPDFTrimBox);
    return [self Rob_imageWithSize:box.size opaque:NO scale:0 block:^(CGContextRef gc) {
        CGContextTranslateCTM(gc, 0, box.size.height);
        CGContextScaleCTM(gc, 1, -1);
        CGContextTranslateCTM(gc, -box.origin.x, -box.origin.y);
        CGContextDrawPDFPage(gc, page);
    }];
}

+ (UIImage *)Rob_imageWithPDFURL:(NSURL *)url pageNumber:(size_t)pageNumber {
    CGPDFDocumentRef document = CGPDFDocumentCreateWithURL((__bridge CFURLRef)(url));
    if (!document)
        return nil;
    UIImage *image = [self Rob_imageWithPDFPage:CGPDFDocumentGetPage(document, pageNumber)];
    CGPDFDocumentRelease(document);
    return image;
}

@end