Send image to server as binary data - iphone

Question

I want to make an iPhone application to send an image to my server.
I want to draw something in iPhone (ex: a signature) as an image to POST binary image to my server (server is JSP). Please tell me what I have to do?
how to use iPhone UI?
how to make binary data from image, etc.

Answer 1

Firstly you can get an NSData object containing either a PNG or JPEG representation of the image data using the UIImagePNGRepresentation and UIImageJPEGRepresentation functions.
// To get the data from a PNG file
NSData *dataForPNGFile = UIImagePNGRepresentation(yourImage);
// To get the data from a JPEG file
NSData *dataForPNGFile = UIImageJPEGRepresentation(yourImage, 0.9f);
(for more information see: UIImage Class Reference)
To finish to upload data from your iPhone to your server you can do this:
- (void)sendImage {
NSData *postData = [nsdata from your original image];
NSString *postLength = [NSString stringWithFormat:#"%d", [postData length]];
// Init and set fields of the URLRequest
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setHTTPMethod:#"POST"];
[request setURL:[NSURL URLWithString:[NSString stringWithString:#"http://yoururl.domain"]]];
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"Content-Type"];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setHTTPBody:postData];
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
if (connection) {
// Return data of the request
NSData *receivedData = [[NSMutableData data] retain];
}
[request release];
}

Answer 2

Use the drawrect method to do signatures on an UIImage. For that you have to use a UITouch delegate
and use the following to convert your UIImage object to NSData
// To get the data from a PNG file
NSData *dataForPNGFile = UIImagePNGRepresentation(yourImage);
// To get the data from a JPEG file
NSData *dataForPNGFile = UIImageJPEGRepresentation(yourImage, 0.9f);