1
我想根據某些變量修改NSImage像素的顏色,而不使用過多的工具包相關庫(例如:CIImage)。所以,以後我可以專注於像素操作算法,並保持它們與平臺無關。在可可中操作NSImage的像素
我的方法是子類NSImage中,並添加屬性
NSBitmapImageRep *originalImage;
在開始階段,我做的:
-(id) initWithContentsOfFile:(NSString *)fileName
{
if([super initWithContentsOfFile:fileName]){
NSRect rect = NSMakeRect(0.0, 0.0, self.size.width, self.size.height);
[self lockFocus];
originalImage = [[NSBitmapImageRep alloc] initWithFocusedViewRect:rect];
[self unlockFocus];
}
return self;
}
現在,當我嘗試更新我做的圖像:
-(void) updateWithVariables:...
{
NSInteger width = [originalImage pixelsWide];
NSInteger height = [originalImage pixelsHigh];
NSInteger count = width * height * 4;
unsigned char *bytes = (unsigned char *)calloc(count, sizeof(unsigned char));
// bytes manipulation
NSBitmapImageRep* newImg = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:&bytes
pixelsWide:width
pixelsHigh:height
bitsPerSample:[originalImage bitsPerSample]
samplesPerPixel:[originalImage samplesPerPixel]
hasAlpha:TRUE
isPlanar:[originalImage isPlanar]
colorSpaceName:[originalImage colorSpaceName]
bitmapFormat:[originalImage bitmapFormat]
bytesPerRow:[originalImage bytesPerRow]
bitsPerPixel:[originalImage bitsPerPixel]];
while([[self representations] count] > 0){
NSBitmapImageRep *rep = [[self representations] objectAtIndex: 0];
[self removeRepresentation:rep];
}
[self addRepresentation:newImg];
[newImg release];
}
但圖像不變。我不確定是否必須使用表示或將包含NSImageView更改爲上下文以繪製新圖像。
謝謝!