Text looks jagged when converting PDF to image using Cocoa on Leopard

Question

Hello,
I have a program that composites the pages of a PDF into a single image with each page stacked on top of each the previous one. The program works fine, but the font rendering quality is much lower when run from anything but a Snow Leopard system. In Leopard, the text looks jagged and not antialiased properly. Does anyone know a fix for this? Here is my code.
NSString* path = [[oPanel filenames] objectAtIndex: 0];
NSPDFImageRep *pdf = [NSPDFImageRep imageRepWithContentsOfFile: path];
int pageHeight = 765;
int pageWidth = 990;
int pages = [pdf pageCount];
int height = pageHeight * pages;
NSImage *compositeImage = [[NSImage alloc] initWithSize:NSMakeSize(pageWidth, height)];
[compositeImage lockFocus];
for (int i = 0; i < pages; i++) {
[pdf setCurrentPage: i];
NSImage *page = [[NSImage alloc] init];
[page addRepresentation:pdf];
NSSize size = [pdf bounds].size;
int width = round(pageHeight * size.width / size.height);
[page drawInRect: NSMakeRect(0, height - pageHeight * (i + 1), width, pageHeight)
fromRect: NSZeroRect
operation: NSCompositeSourceOver
fraction: 1.0];
[page release];
[compositeImage unlockFocus];
NSBitmapImageRep *rep = [NSBitmapImageRep imageRepWithData: [compositeImage TIFFRepresentation]];
NSData *imageData = [rep representationUsingType: NSJPEGFileType properties: nil];
[imageData writeToFile:@"/Users/devongovett/Desktop/out.jpg" atomically: YES];
Thanks for any help you might be able to give!
Devon
Message was edited by: devongovett
Message was edited by: devongovett

Answer 1

devongovett wrote:
The program works fine, but the font rendering quality is much lower when run from anything but a Snow Leopard system. In Leopard, the text looks jagged and not antialiased properly.
Without knowing anything about how to draw into a PDF in code: the problem might not be in your code but in Leopard's rendering.
I bet you are testing just with Apple's own Preview app -- can you test with something else, for example, the Acrobat Reader, on both systems? There is a good chance your image is just fine.