Iphone UIImage字节顺序已更改
我正在使用Iphone UIImage字节顺序已更改,iphone,ios,opengl-es,uiimage,cgimage,Iphone,Ios,Opengl Es,Uiimage,Cgimage,我正在使用[uiImage drawAtPoint]绘制新图像。但结果是颜色变了。我的原始图像uiImage为红色，而生成的图像newImage为蓝色。这是我的密码： UIImage* uiImage = [UIHelper loadImage:fileName]; NSString *text = [ApplicationSettings instance].user.name; UIGraphicsBeginImageContext(uiImage.size); [uiImage drawA
[uiImage drawAtPoint]uiImagenewImageUIImage* uiImage = [UIHelper loadImage:fileName];
NSString *text = [ApplicationSettings instance].user.name;
UIGraphicsBeginImageContext(uiImage.size);
[uiImage drawAtPoint: CGPointZero];
[text drawAtPoint: CGPointMake(10, 10) withFont: [UIFont systemFontOfSize: 12]];
UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return [Texture createTexture: newImage];
[Texture createTexture]+ (Texture*) createTextureWithImage:(UIImage*)image {
Texture* tex = [[[Texture alloc] init] autorelease];
if ([tex loadImage:image])
return tex;
else {
NSLog(@"Failed to load image %@", image);
return nil;
}
}
- (BOOL)loadImage:(UIImage *)image {
BOOL ret = NO;
if (image) {
// Get the inner CGImage from the UIImage wrapper
CGImageRef cgImage = image.CGImage;
// Get the image size
width = CGImageGetWidth(cgImage);
height = CGImageGetHeight(cgImage);
// Record the number of channels
channels = CGImageGetBitsPerPixel(cgImage)/CGImageGetBitsPerComponent(cgImage);
// Generate a CFData object from the CGImage object (a CFData object represents an area of memory)
CFDataRef imageData = CGDataProviderCopyData(CGImageGetDataProvider(cgImage));
// Copy the image data for use by Open GL
ret = [self copyImageDataForOpenGL: imageData];
CFRelease(imageData);
}
return ret;
}
[texture copyImageDataForOpenGL]- (BOOL)copyImageDataForOpenGL:(CFDataRef)imageData {
if (pngData) {
free(pngData);
}
pngData = (unsigned char*)malloc(width * height * channels);
const int rowSize = width * channels;
const unsigned char* pixels = (unsigned char*)CFDataGetBytePtr(imageData);
// Copy the row data from bottom to top
for (int i = 0; i < height; ++i) {
memcpy(pngData + rowSize * i, pixels + rowSize * (height - 1 - i), width * channels);
}
return YES;
}
-（BOOL）copyImageDataForOpenGL:（CFDataRef）imageData{
if（pngData）{
自由（pngData）；
}
pngData=（无符号字符*）malloc（宽度*高度*通道）；
const int rowSize=宽度*通道；
const unsigned char*pixels=（unsigned char*）CFDataGetBytePtr（imageData）；
//从下至上复制行数据
对于（int i=0；i返回[Texture createTexture:uiImage]返回[Texture createTexture:newImage]uiImageUIImageWriteToSavedPhotosAlbum（newImage，nil，nil，nil）并且保存的图像是正确的
我打印了CGImageGetBitmapInfo（uiImage.CGImage））
和CGImageGetBitmapInfo（newImage.CGImage）
，它们不一样 这是我的当前正确版本的copyImageDataForOpenGL
- (BOOL)copyImageDataForOpenGL:(CGImageRef)image {
if (pngData) {
free(pngData);
}
pngData = (GLubyte*)malloc(width * height * channels);
const int rowSize = width * channels;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
NSUInteger bytesPerPixel = channels;
NSUInteger bytesPerRow = bytesPerPixel * width;
NSUInteger bitsPerComponent = 8;
CGContextRef context = CGBitmapContextCreate(pngData, width, height,
bitsPerComponent, bytesPerRow, colorSpace,
kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
CGColorSpaceRelease(colorSpace);
CGContextClearRect(context, CGRectMake(0, 0, width, height));
CGContextTranslateCTM(context, 0,0);
CGContextDrawImage(context, CGRectMake(0, 0, width, height), image);
[ARRenderer flipRGBData: pngData bytesPerRow:bytesPerRow height:height];
return YES;
}
其中[Arrender flipRGBData]
定义为
+ (void)flipRGBData:(GLubyte*)data bytesPerRow:(int)bytesPerRow height:(int)height {
GLubyte* swp = (GLubyte*)malloc(bytesPerRow);
for (int h = 0; h < height / 2; h++) {
memcpy(swp, data + (height - 1 - h) * bytesPerRow, bytesPerRow);
memcpy(data + (height - 1 - h) * bytesPerRow, data + h * bytesPerRow, bytesPerRow);
memcpy(data + h * bytesPerRow, swp, bytesPerRow);
}
free(swp);
}
+（void）flipRGBData:（GLubyte*）数据bytesPerRow:（int）bytesPerRow height:（int）height{
GLubyte*swp=（GLubyte*）malloc（bytesPerRow）；
对于（int h=0；h
这是我的当前正确版本的copyImageDataForOpenGL
- (BOOL)copyImageDataForOpenGL:(CGImageRef)image {
if (pngData) {
free(pngData);
}
pngData = (GLubyte*)malloc(width * height * channels);
const int rowSize = width * channels;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
NSUInteger bytesPerPixel = channels;
NSUInteger bytesPerRow = bytesPerPixel * width;
NSUInteger bitsPerComponent = 8;
CGContextRef context = CGBitmapContextCreate(pngData, width, height,
bitsPerComponent, bytesPerRow, colorSpace,
kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
CGColorSpaceRelease(colorSpace);
CGContextClearRect(context, CGRectMake(0, 0, width, height));
CGContextTranslateCTM(context, 0,0);
CGContextDrawImage(context, CGRectMake(0, 0, width, height), image);
[ARRenderer flipRGBData: pngData bytesPerRow:bytesPerRow height:height];
return YES;
}
其中[Arrender flipRGBData]
定义为
+ (void)flipRGBData:(GLubyte*)data bytesPerRow:(int)bytesPerRow height:(int)height {
GLubyte* swp = (GLubyte*)malloc(bytesPerRow);
for (int h = 0; h < height / 2; h++) {
memcpy(swp, data + (height - 1 - h) * bytesPerRow, bytesPerRow);
memcpy(data + (height - 1 - h) * bytesPerRow, data + h * bytesPerRow, bytesPerRow);
memcpy(data + h * bytesPerRow, swp, bytesPerRow);
}
free(swp);
}
+（void）flipRGBData:（GLubyte*）数据bytesPerRow:（int）bytesPerRow height:（int）height{
GLubyte*swp=（GLubyte*）malloc（bytesPerRow）；
对于（int h=0；h
我建议使用UIGraphicsBeginImageContextWithOptions（uiImage.size，NO，0.0）；而不是UIGraphicsBeginImageContext（uiImage.size）；以支持视网膜屏幕渲染。但是，这不应成为图像渲染翻转颜色的原因。我想稍后再深入了解一下-尽快给您回信（只要尚未解决；）@Markus它无法使用UIGraphicsBeginImageContextWithOptions
。您根本看不到任何图像吗？请尝试使用不透明的“是”而不是“否”（第二个参数），如果您不介意，请共享结果。@Markus我的意思是它保持不变。我建议使用UIGraphicsBeginImageContextWithOptions（uiImage.size，否，0.0）；而不是UIGraphicsBeginImageContext（uiImage.size）；以支持视网膜屏幕渲染。但是，这不应成为图像渲染翻转颜色的原因。我想稍后再深入了解一下-尽快给您回信（只要尚未解决；）@Markus它无法使用UIGraphicsBeginImageContextWithOptions
。您根本看不到任何图像吗？请尝试使用不透明的“是”而不是“否”（第二个参数），如果您不介意，请共享结果。@Markus我的意思是它保持不变。