从 CocoaDev ......如果你NSImage
在创建它之后做任何事情:
NSData *imageData = [image TIFFRepresentation];
NSBitmapImageRep *imageRep = [NSBitmapImageRep imageRepWithData:imageData];
NSNumber *compressionFactor = [NSNumber numberWithFloat:0.9];
NSDictionary *imageProps = [NSDictionary dictionaryWithObject:compressionFactor
forKey:NSImageCompressionFactor];
imageData = [imageRep representationUsingType:NSJPEGFileType properties:imageProps];
[imageData writeToFile:filename atomically:YES];
如果您对之前没有真正做任何其他事情NSImage
:
NSArray *representations = [myImage representations];
NSNumber *compressionFactor = [NSNumber numberWithFloat:0.9];
NSDictionary *imageProps = [NSDictionary dictionaryWithObject:compressionFactor
forKey:NSImageCompressionFactor];
NSData *bitmapData = [NSBitmapImageRep representationOfImageRepsInArray:representations
usingType:NSJPEGFileType
properties:imageProps];
[bitmapData writeToFile:filename atomically:YES];