This is the code I am using to display the value of the slider inside my thumb image. But still the value is getting displayed below the slider. Please help me.
-(IBAction)sliderValueChanged:(id)sender
{
UISlider *aSlider = (UISlider *)sender;
[aSlider setThumbImage:
[self addText:self.thumbImage text:[NSString stringWithFormat:#"%.0f",
aSlider.value * 100]] forState:aSlider.state];
}
//Add text to UIImage
-(UIImage *)addText:(UIImage *)img text:(NSString *)text1{
int w = img.size.width;
int h = img.size.height;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(NULL, w, h, 8, 4 * w,
colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextDrawImage(context, CGRectMake(0, 0, w, h), img.CGImage);
char* text= (char *)[text1 cStringUsingEncoding:NSASCIIStringEncoding];
CGContextSelectFont(context, "Arial",12, kCGEncodingMacRoman);
CGContextSetTextDrawingMode(context, kCGTextFill);
CGContextSetRGBFillColor(context, 0, 0, 0, 1);
CGContextShowTextAtPoint(context,3,8,text, strlen(text));
CGImageRef imgCombined = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
UIImage *retImage = [UIImage imageWithCGImage:imgCombined];
CGImageRelease(imgCombined);
return retImage;
Related
I just want to put the current geolocation on a photo taken from my iPhone/iPad.Is this possible?I have already got the geolocation but can I edit the photo programmatically by adding a text label over it.
Thanks for any help.
You can add text on image using :
//Add text to UIImage
-(UIImage *)addText:(UIImage *)img text:(NSString *)text1{
int w = img.size.width;
int h = img.size.height;
//lon = h - lon;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(NULL, w, h, 8, 4 * w, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextDrawImage(context, CGRectMake(0, 0, w, h), img.CGImage);
CGContextSetRGBFillColor(context, 0.0, 0.0, 1.0, 1);
char* text = (char *)[text1 cStringUsingEncoding:NSASCIIStringEncoding];// "05/05/09";
CGContextSelectFont(context, "Arial", 18, kCGEncodingMacRoman);
CGContextSetTextDrawingMode(context, kCGTextFill);
CGContextSetRGBFillColor(context, 255, 255, 255, 1);
//rotate text
CGContextSetTextMatrix(context, CGAffineTransformMakeRotation( -M_PI/4 ));
CGContextShowTextAtPoint(context, 4, 52, text, strlen(text));
CGImageRef imageMasked = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
return [UIImage imageWithCGImage:imageMasked];
}
Hope it helps you.
here is the sample method which will return you a image with text on it
-(UIImage*) getImageWithText:(UIImage*) sourceImage
{
UIGraphicsBeginImageContext(sourceImage.size);
[sourceImage drawAtPoint:CGPointZero];
[#"someText" drawAtPoint:CGPointMake(x,y) [UIFont systemFontOfSize:14]]
UIImage* imageWithText = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return imageWithText;
}
I'm trying to add a text to an UIImage and I'm getting a pixelated drawing.
I have tried some other answers with no success:
Drawing on the retina display using CoreGraphics - Image pixelated
Retina display core graphics font quality
Drawing with Core Graphics looks chunky on Retina display
My code:
-(UIImage *)addText:(UIImage *)imgV text:(NSString *)text1
{
int w = self.frame.size.width * 2;
int h = self.frame.size.height * 2;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate
(NULL, w, h, 8, 4 * w, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextDrawImage(context, CGRectMake(0, 0, w, h), imgV.CGImage);
CGContextSetRGBFillColor(context, 0.0, 0.0, 1.0, 1);
char* text = (char *)[text1 cStringUsingEncoding:NSASCIIStringEncoding];
CGContextSelectFont(context, "Arial", 24, kCGEncodingMacRoman);
// Adjust text;
CGContextSetTextDrawingMode(context, kCGTextInvisible);
CGContextShowTextAtPoint(context, 0, 0, text, strlen(text));
CGPoint pt = CGContextGetTextPosition(context);
float posx = (w/2 - pt.x)/2.0;
float posy = 54.0;
CGContextSetTextDrawingMode(context, kCGTextFill);
CGContextSetRGBFillColor(context, 255, 255, 255, 1.0);
CGContextShowTextAtPoint(context, posx, posy, text, strlen(text));
CGImageRef imageMasked = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
return [UIImage imageWithCGImage:imageMasked];
}
Like Peter said, use UIGraphicsBeginImageContextWithOptions. You might want to pass image.scale to the scale attribute (where image.scale is the scale of one of the images you're drawing), or simply use [UIScreen mainScreen].scale.
This code can be made simpler overall. Try something like:
// Create the image context
UIGraphicsBeginImageContextWithOptions(_baseImage.size, NO, _baseImage.scale);
// Draw the image
CGRect rect = CGRectMake(0, 0, _baseImage.size.width, _baseImage.size.height);
[_baseImage drawInRect:rect];
// Get a vertically centered rect for the text drawing
rect.origin.y = (rect.size.height - FONT_SIZE) / 2 - 2;
rect = CGRectIntegral(rect);
rect.size.height = FONT_SIZE;
// Draw the text
UIFont *font = [UIFont boldSystemFontOfSize:FONT_SIZE];
[[UIColor whiteColor] set];
[text drawInRect:rect withFont:font lineBreakMode:NSLineBreakByClipping alignment:NSTextAlignmentCenter];
// Get and return the new image
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
Where text is an NSString object.
I was facing the exact same problem and posted a question last night to which no-one replied. I have combined fnf's suggested changes with Clif Viegas's answer in the following question:
CGContextDrawImage draws image upside down when passed UIImage.CGImage
to come up with the solution. My addText method is slightly different from yours:
+(UIImage *)addTextToImage:(UIImage *)img text:(NSString *)text1{
int w = img.size.width;
int h = img.size.height;
CGSize size = CGSizeMake(w, h);
if (UIGraphicsBeginImageContextWithOptions != NULL) {
UIGraphicsBeginImageContextWithOptions(size, NO, 0.0);
} else {
UIGraphicsBeginImageContext(size);
}
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(context, 0,h);
CGContextScaleCTM(context, 1.0, -1.0);
CGContextDrawImage(context, CGRectMake(0, 0, w, h), img.CGImage);
CGContextSetRGBFillColor(context, 0.0, 0.0, 1.0, 1);
char* text = (char *)[text1 cStringUsingEncoding:NSASCIIStringEncoding];// \"05/05/09\";
CGContextSelectFont(context, "Times New Roman", 14, kCGEncodingMacRoman);
CGContextSetTextDrawingMode(context, kCGTextFill);
CGContextSetRGBFillColor(context, 0, 0, 0, 1);
//rotate text
CGContextSetTextMatrix(context, CGAffineTransformMakeRotation( -M_PI/8 ));
CGContextShowTextAtPoint(context, 70, 88, text, strlen(text));
CGColorSpaceRelease(colorSpace);
UIGraphicsEndImageContext();
return newImg;
}
In summary, what I have done is add
if (UIGraphicsBeginImageContextWithOptions != NULL) {
UIGraphicsBeginImageContextWithOptions(size, NO, 0.0);
} else {
UIGraphicsBeginImageContext(size);
}
Remove
// CGContextRef context = CGBitmapContextCreate(NULL, w, h, 8, 4 * w, colorSpace, kCGImageAlphaPremultipliedFirst);
and put
CGContextRef context = UIGraphicsGetCurrentContext();
instead. But this causes the image to be upside down. Hence I put
CGContextTranslateCTM(context, 0,h);
CGContextScaleCTM(context, 1.0, -1.0);
just before
CGContextDrawImage(context, CGRectMake(0, 0, w, h), img.CGImage);
This way you can use CG functions instead of using drawInRect etc.
Don't forget
UIGraphicsEndImageContext
at the end. Hope this helps.
This code is not working and i do not understand the mistake.
Please help.
-(UIImage *)addText:(UIImage *)img text:(NSString *)text1
{
int w = img.size.width;
int h = img.size.height;
//lon = h - lon;
char* text = (char *)[text1 cStringUsingEncoding:NSASCIIStringEncoding];
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
/*UIGraphicsBeginImageContext(self.view.bounds.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
CGContextShowTextAtPoint(UIGraphicsGetCurrentContext(), 50, 100, text, strlen(text));
UIImage *viewImage =UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSLog(#"View Image : %#",viewImage);*/
CGContextRef context = CGBitmapContextCreate(NULL, w, h, 8, 4 * w, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextDrawImage(context, CGRectMake(0, 0, w, h), img.CGImage);
CGContextSetRGBFillColor(context, 0.0, 0.0, 1.0, 1);
//char* text = (char *)[text1 cStringUsingEncoding:NSASCIIStringEncoding];// "05/05/09";
CGContextSelectFont(context, "Arial", 18, kCGEncodingMacRoman);
CGContextSetTextDrawingMode(context, kCGTextFill);
CGContextSetRGBFillColor(context, 255, 255, 255, 1);
//rotate text
CGContextShowTextAtPoint(context, 0, 50, text, strlen(text));
CGContextSetTextMatrix(context, CGAffineTransformMakeRotation( -M_PI/4 ));
CGContextShowTextAtPoint(context, 50, 100, text, strlen(text));
//UIImage *compositeImage = UIGraphicsGetImageFromCurrentImageContext();
CGImageRef imageMasked = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
NSLog(#"Image : %#",[UIImage imageWithCGImage:imageMasked]);
return [UIImage imageWithCGImage:imageMasked];
//return viewImage;
}
Unless you have a reason to avoid NSString UIKit additions, this will suffice:
+(UIImage*) drawText:(NSString*) text
inImage:(UIImage*) image
atPoint:(CGPoint) point
font:(UIFont*) font
color:(UIColor*) color
{
UIGraphicsBeginImageContextWithOptions(image.size, FALSE, 0.0);
[image drawInRect:CGRectMake(0,0,image.size.width,image.size.height)];
CGRect rect = CGRectMake(point.x, point.y, image.size.width, image.size.height);
[color set];
[text drawInRect:CGRectIntegral(rect) withFont:font];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
Your code does work.
Make sure the string you are passing into it is not empty.
I want to write some text in a UIImage, I've found this link and it works, but if you try to write some special characters like "á, é, í, ö, ô..." then it fails.
The code:
//Add text to UIImage
-(UIImage *)addText:(UIImage *)img text:(NSString *)text1{
int w = img.size.width;
int h = img.size.height;
//lon = h - lon;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(NULL, w, h, 8, 4 * w, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextDrawImage(context, CGRectMake(0, 0, w, h), img.CGImage);
CGContextSetRGBFillColor(context, 0.0, 0.0, 1.0, 1);
char* text = (char *)[text1 cStringUsingEncoding:NSASCIIStringEncoding];// "05/05/09";
CGContextSelectFont(context, "Arial", 18, kCGEncodingMacRoman);
CGContextSetTextDrawingMode(context, kCGTextFill);
CGContextSetRGBFillColor(context, 255, 255, 255, 1);
//rotate text
CGContextSetTextMatrix(context, CGAffineTransformMakeRotation( -M_PI/4 ));
CGContextShowTextAtPoint(context, 4, 52, text, strlen(text));
CGImageRef imageMasked = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
return [UIImage imageWithCGImage:imageMasked];
}
Is there any idea to solve this issue?
Thank you.
EDIT:
I've tried to change:
char* text = (char *)[text1 cStringUsingEncoding:NSASCIIStringEncoding];
to
char* text = (char *)[text1 cStringUsingEncoding:NSUTF8StringEncoding];
but it doesn't work.
Another user told me how to do it:
-(UIImage *)writeText:(NSString *)text1 toImage:(UIImage *)img{
CGSize sizeText = [text1 sizeWithFont:[UIFont fontWithName:#"Helvetica" size:36] minFontSize:36 actualFontSize:nil forWidth:783 lineBreakMode:UILineBreakModeTailTruncation];
CGFloat posX = 1024.0 - 230.0 - sizeText.width;
UIGraphicsBeginImageContextWithOptions(img.size, NO, 0.0f);
[img drawAtPoint:CGPointMake(0.0f, 0.0f)];
[text1 drawAtPoint:CGPointMake(posX, 588.0) withFont:[UIFont fontWithName:#"Helvetica" size:36]];
UIImage *result = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return result;
}
In this link
try using NSUTF8StringEncoding instead of NSASCIIStringEncoding
I want to add watermarks on an UIImage.
For that i have googled and also studied questions on this website like this
But did not get any help.
Just add image on your image view and then add one subview on it and set alpha of subview less so it look like water mark or you can add label, but in label you have to change its angel to show angular
If your UIImage is suppose in the imageview and watermark image in the imageview1, then use method of UIView class
[imageview addSubview: imageview1];
.
Try this
//get image width and height
int w = img.size.width;
int h = img.size.height;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
//create a graphic context with CGBitmapContextCreate
CGContextRef context = CGBitmapContextCreate(NULL, w, h, 8, 4 * w, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextDrawImage(context, CGRectMake(0, 0, w, h), img.CGImage);
CGContextSetRGBFillColor(context, 0.0, 1.0, 1.0, 1);
char* text = (char *)[text1 cStringUsingEncoding:NSASCIIStringEncoding];
CGContextSelectFont(context, "Georgia", 30, kCGEncodingMacRoman);
CGContextSetTextDrawingMode(context, kCGTextFill);
CGContextSetRGBFillColor(context, 255, 0, 0, 1);
CGContextSetTextMatrix(context, CGAffineTransformMakeRotation( -M_PI/4 ));
CGContextShowTextAtPoint(context, 40, 20, text, strlen(text));
//Create image ref from the context
CGImageRef imageMasked = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
return [UIImage imageWithCGImage:imageMasked];