iphone : compress image in a UIImageView so that it can be uploaded to server
Hey I have a situation I am picking a image from camera and trying to upload it to server image size is 1.6 MB
How can I compress this image to upload it to server?
-(UIImage*)resizedImage:(UIImage*)inImage inRect:(CGRect)thumbRect {
CGImageRef imageRef = [inImage CGImage];
CGImageAlphaInfo alphaInfo = CGImageGetAlphaInfo(imageRef);
if (alphaInfo == kCGImageAlphaNone)
alphaInfo = kCGImageAlphaNoneSkipLast;
// Build a bitmap context that's the size of the thumbRect
CGFloat bytesPerRow;
if( thumbRect.size.width > thumbRect.size.height ) {
bytesPerRow = 4 * thumbRect.size.width;
} else {
bytesPerRow = 4 * thumbRect.size.height;
}
CGContextRef bitmap = CGBitmapContextCreate(
NULL,
thumbRect.size.width, // width
thumbRect.size.height, // height
8, //CGImageGetBitsPerComponent(imageRef), // really needs to always be 8
bytesPerRow, //4 * thumbRect.size.width, // rowbytes
CGImageGetColorSpace(imageRef),
alphaInfo
);
// Draw into the context, this scales the image
CGContextDrawImage(bitmap, thumbRect, imageRef);
// Get an image from the context and a UIImage
CGImageRef ref = CGBitmapContextCreateImage(bitmap);
UIImage* result = [UIImage imageWithCGImage:ref];
CGContextRelease(bitmap); // ok if NULL
CGImageRelease(ref);
return result;
}
- (void)uploadImage {
/*
turning the image into a NSData object
getting the image back out of the UIImageView
setting the quality to 90
*/
[activityIndicator startAnimating];
UIImage *compressedImge=[UIImage imageWithCGImage:itemImageView.image.CGImage scale:0.15 orientation:UIImageOrientationUp];
CGRect sz = CGRectMake(0.0f, 0.0f, 69.0f, 69.0f);
UIImage *smallImage = [self resizedImage:compressedImge inRect:sz];
NSData *imageData = UIImageJPEGRepresentation(smallImage, 0.15);
// setting up the URL to post to
NSString *urlString = @"http://example.co/imageuploader.php";
// setting up the request object now
NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
[request setURL:[NSURL URLWithString:urlString]];
[request setHTTPMetho开发者_JAVA百科d:@"POST"];
/*
add some header info now
we always need a boundary when we post a file
also we need to set the content type
You might want to generate a random boundary.. this is just the same
as my output from wireshark on a valid html post
*/
NSString *boundary = [NSString stringWithString:@"---------------------------14737809831466499882746641449"];
NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",boundary];
[request addValue:contentType forHTTPHeaderField: @"Content-Type"];
/*
now lets create the body of the post
*/
NSMutableData *body = [NSMutableData data];
[body appendData:[[NSString stringWithFormat:@"\r\n--%@\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"userfile\"; filename=\"ipodfile%@.jpeg\"\r\n",self.fileID] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[[NSString stringWithString:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[body appendData:[NSData dataWithData:imageData]];
[body appendData:[[NSString stringWithFormat:@"\r\n--%@--\r\n",boundary] dataUsingEncoding:NSUTF8StringEncoding]];
// setting the body of the post to the reqeust
[request setHTTPBody:body];
//[request did];
// now lets make the connection to the web
NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
NSString *returnString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];
NSLog(returnString);
}
See this question: What's the easiest way to resize/optimize an image size with the iPhone SDK? I had the same exact question a couple months ago, this lets you resize the actual image data to whatever resolution you want.
You're already compressing it heavily with UIImageJPEGRepresentation(smallImage, 0.15);
.
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