Export a TIFF with transparency
Export a TIFF with transparency
- Subject: Export a TIFF with transparency
- From: Lorenzo <email@hidden>
- Date: Tue, 18 Nov 2003 16:53:47 +0100
Hi,
I have a TIFF document made by Photoshop. It has a transparent background.
But any time I save it with my Cocoa application, I lose the transparency of
the background. The background becomes white.
I do this:
id rep = [NSBitmapImageRep imageRepWithContentsOfFile:filePath];
[rep representationUsingType:NSPNGFileType properties:nil];
[iconFormatRep writeToFile:newFilePath atomically:YES];
No matter if I export to an NSPNGFileType or NSTIFFFileType. If the original
file is a TIFF, the final background becomes white all the time.
Instead if I use an original PNG file, I can export it like PNG or TIFF with
the transparent background.
All I have to do is to read an image, cut the size, choose the output
format, change resolution, change depth, and save. I did most of this, but
for example, in order to change the resolution I have to use the Carbon API
GraphicsExportSetResolution, so it's a mix of Carbon and Cocoa APIs.
Can anyone explain me please how to do that?
Sincerely I am a little bit confused between NSImage, NSImageRep,
NSBitmapImageRep, NSData, array of representations, TIFFRepresentation...
plus the old Carbon APIs. Maybe someone can clarify to me the basic
concepts. I have read the documentation but there are some concepts not so
clear to me.
Thank you
--
Lorenzo
email: email@hidden
_______________________________________________
cocoa-dev mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/cocoa-dev
Do not post admin requests to the list. They will be ignored.