I'm making a photo gallery app.
I'm compressing the images
NSData *imageData = UIImageJPEGRepresentation(image,0.5)
and then want to create a duplicate (for thumbnails) that I'll compress even further
NSData *imageData = UIImageJPEGRepresentation(image,0.2)
I'm a little stuck on the middle step of how to create a duplicate, anyone know if there is a function for this?
Probably you can convert NSData to UIImage.
Swift3:
let imageData = UIImageJPEGRepresentation(thumbImage,0.5)
let thumbImage = UIImage(data:UIImageJPEGRepresentation(UIImage(data: imageData),0.2))
Objective C:
NSData *imageData = UIImageJPEGRepresentation(image,0.5)
UIImage *thumb = [UIImage imageWithData: UIImageJPEGRepresentation([UIImage imageWithData: imageData],0.5)];
Related
I think everything is in the title:
I have a UIImage that I need to convert to base64 without using UIImagePNGRepresentation or UIImageJPEGRepresentation. Objective C is what I code in.
Is this possible?
When converting to base64 string:
NSData *imageBase64Data = [ImageData base64EncodedDataWithOptions:0];
NSString *imageBase64String = [[NSString alloc] initWithData:imageBase64Data encoding: NSUTF8StringEncoding];
And converting it back:
NSData *data = [[NSData alloc] initWithBase64EncodedString:string options:0];
UIImage *image = [UIImage imageWithData:data];
as you can see from the code, we just converted the string back to data(originally image)
Convert the image to NSData without assigning a png or jpg representation like this:
CGDataProviderRef provider = CGImageGetDataProvider(image.CGImage);
NSData* data = (id)CFBridgingRelease(CGDataProviderCopyData(provider));
Then convert the data to a base64 string using a library like this one: https://github.com/ekscrypto/Base64
I Get this kind of JSON:
NOTE: I put dots in "content" because it is too long byte array abd just to explain the situation.
{
"id":"53abc6a7975a9c10c292f670",
"nfcId":"testse",
"company":"TESt",
"qrId":"testvalue",
"address":"ajs;ldfh",
"mimeType":"IMAGE",
"url":"",
"content":"iVBORw0KGgoAAAANSUhEUgAA....."
}
And im trying to get this Json and diplay this information
the "content" field has a Byte array converted on the server from Image to byte array.
I use this code in xCode to convert those bytes to NSData, then to UIImage to be able to display it in UIImageView:
NSData *dataImage = [jsonArray[key] dataUsingEncoding:NSUTF8StringEncoding];
NSLog(#"data = %#", dataImage);
UIImage *img = [UIImage imageWithData:dataImage];
NSLog(#"img = %#", img);
The image is always gives me null.Although, data give me array of data.
I tried all kinds of encodings as a NSData parameters also:
dataUsingEncoding:NSASCIIStringEncoding
dataUsingEncoding:NSUTF8StringEncoding
dataUsingEncoding:NSUTF16StringEncoding
dataUsingEncoding:NSUTF32StringEncoding
I've used code like this before
NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:#"data:image/png;base64,%#",jsonArray[key]]];
NSData *imageData = [NSData dataWithContentsOfURL:url];
UIImage *img = [UIImage imageWithData:imageData];
Note that initWithBase64EncodedString is only available from iOS7 onwards
I tried this code just right now and it works:
NSData* dataImage = [[NSData alloc] initWithBase64EncodedString:jsonArray[key] options:0];
UIImage *img = [UIImage imageWithData:dataImage];
The "content" encoded by Base64 String type.
I have tried google and stackoverflow but not able to get a satisfactory answer I am a newbie and trying to encode image send/upload to server then decode same image in base64 image and show in my collectionview's Cell's imageview.
I have encoded the image in base64 successfully, I have checked the encoded string in online base64 formatter and getting my image in output so my encoding is working fine.
2 Getting the below error while decoding.....
<Error>: ImageIO: JPEG Unsupported marker type 0x6c
<Error>: ImageIO: JPEG Corrupt JPEG data: 1 extraneous bytes before marker 0x6c
I am using the below code to decode the image
NSString *imageURL = [imagename objectAtIndex:indexPath.row];
NSData *imageData = [Base64 decode:imageURL];
ImageView.image = [UIImage imageWithData:imageData];
Any Suggestion and Advice will be appreciated....
Try this...
NSString *imageString = [imagename objectAtIndex:indexPath.row];
NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:#"data:image/png;base64,%#",imageString]];
NSData *imageData = [NSData dataWithContentsOfURL:url];
ImageView.image = [UIImage imageWithData:imageData];
I am getting the following response from a server:
{
"userId": "72e823ebc0c07fa99f279d6435e2c6ce",
"userHash": null,
"md5": "e993b7e9ec74bcdc1b1b7baec7d1cdd2",
"highres": null,
"thumbnail": "/9j/4AAQSkZJRgABAgAAAQABAAD/2wBDAAgGBgcGBQgHBwcJCQgKDBQNDAsLDBkSEw8UHRofHh0aHBwgJC4nICIsIxwcKDcpLDAxNDQ0
Hyc5PTgyPC4zNDL/2wBDAQkJCQwLDBgNDRgyIRwhMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjIyMjL/wAARCAAyADIDASIAAhEBAxEB/
8QAHwAAAQUBAQEBAQEAAAAAAAAAAAECAwQFBgcICQoL/8QAtRAAAgEDAwIEAwUFBAQAAAF9AQIDAAQRBRIhMUEGE1FhByJxFDKBkaEII0KxwRVS0fAkM2Jygg
kKFhcYGRolJicoKSo0NTY3ODk6Q0RFRkdISUpTVFVWV1hZWmNkZWZnaGlqc3R1dnd4eXqDhIWGh4iJipKTlJWWl5iZmqKjpKWmp6ipqrKztLW2t7i5usLDxMXGx8jJytL
T1NXW19jZ2uHi4+Tl5ufo6erx8vP09fb3+Pn6/8QAHwEAAwEBAQEBAQEBAQAAAAAAAAECAwQFBgcICQoL/8QAtREAAgECBAQDBAcFBAQAAQJ3AAECAxEEBSExBhJ
BUQdhcRMiMoEIFEKRobHBCSMzUvAVYnLRChYkNOEl8RcYGRomJygpKjU2Nzg5OkNERUZHSElKU1RVVldYWVpjZGVmZ2hpanN0dXZ3eHl6goOEhYaHiImKkpOUlZa
XmJmaoqOkpaanqKmqsrO0tba3uLm6wsPExcbHyMnK0tPU1dbX2Nna4uPk5ebn6Onq8vP09fb3+Pn6/9oADAMBAAIRAxEAPwD0CfRbZY3IzuAyOak0nTLOW0UzBt+e
cGpppcxvg87ajt76Cw0R7uVC3lgtj1rREMvtpVijo6q+5fu81Wu/EGmeFFMlwTiTkgHmnadqqanYwXqL5ayDIU9q8C8ceILq+8QXUU0haOFyqgelVo9xHu1v8U9BuLhIlM
g3fxHGBXWf2pYmAzLdRMgXdw4NfImmQXN1bNIHKQbsbj616DpdvcQ6RHsnLfNyc1jNpbGqi+p6+fHOmgkbJePaivMvN9jRWPOyuU6Rb9ZbaTyn3Ng4Feaaj48utIuNQ0
+6gaaOZNiKT/q/etvSPEEN1qr2dsoMAXcJMdTXJ61aaLe+K7v+2b1rSIAbSozmutbmD2Lnhzxvq2h26me1e6tZB+7JPCCuauBHqGvTXV04hjuHL4Pato+CdcvlWTSZGn0w/
wCpdmxkV01v8IIZbWOa51NhPtyybhhT6U7Kw07M56xvbGK3NpFGrpuyYx39627PXoJrmSwtYgFij35Hc+ldX4L8IDStMvoryxtpk2vtuHYbhxxXiVrcTaZ4gujAxk3uynJ6DN
YOkbqonY7I+KLgEj+zz+dFZWQeTIaKz9ia3j3I9F1+8e2ElrDArg5cnj5awdfli1PUJbqR/vDtWTBev9i+zKSOc5FUHDocFifxrpujiOoj8b6vDpkelQymOCIbUKNg4qEajrcoBW/
uMe8hrnIpPLmRm6A1urq8JRRtORTTBov2q+JtRlFtb6jcDdxgykA1txfC3xRBKks3kruIO5nxmsrRdVd7sKgwi/MD7ivZ/C+taV490waVq8rRX0XKurbQQOlS2UkcaPh5reB+
9tf+/gor0j/hVqZ4upsf9dDRSuOx8q2v3z9KJetFFBmyCTotSRfdNFFNF9Do/DvR/oa2vCrMPEdphiP346H3oopD6H1un+rX6CiiipGf/9k="
}
Thumbnail is a byte array and I want to convert that into NSData, then into an UIImage.
When I do the following, I end up with nil:
NSData *pictureData = [NSData dataWithBytes:[updatedData objectForKey:#"thumbnail"]];
UIImage *img = [[UIImage alloc] initWithData:pictureData];
How can I fix this?
This is not a "byte array". This is a NSString which contains a Base64 encoded image.
iOS7 has built in support for Base64 encoded data, for older versions you have to roll your own code. There are plenty of implementations available
This works on iOS7:
// NSString *base64String = [updatedData objectForKey:#"thumbnail"];
NSString *base64String = #"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";
NSData *data = [[NSData alloc] initWithBase64EncodedString:base64String options:NSDataBase64DecodingIgnoreUnknownCharacters];
UIImage *image = [UIImage imageWithData:data];
And that's your image:
I need to get gifs with different colors from this library: https://github.com/samvermette/SVPulsingAnnotationView
In the library I have access to the layer of the MKAnnotationView. But I need an animated gif of the generated annotation to use in a non-iOS project.
I used renderInContext to create pngs from the CALayer (result). Then I created the gifs using python.
UIGraphicsBeginImageContextWithOptions(result.bounds.size, result.opaque, 0.0);
[result renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSString *pngFilePath = [NSString stringWithFormat:#"%#/blue dot.png",docDir];
NSData *data1 = [NSData dataWithData:UIImagePNGRepresentation(image)];
[data1 writeToFile:pngFilePath atomically:YES];