ocrapi.m

- (void)callOCRSpace {
    // Create URL request
    NSURL *url = [NSURL URLWithString:@"https://api.ocr.space/Parse/Image"];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
    [request setHTTPMethod:@"POST"];
    NSString *boundary = @"randomString";
    [request addValue:[NSString stringWithFormat:@"multipart/form-data; boundary=%@", boundary] forHTTPHeaderField:@"Content-Type"];
    
    NSURLSession *session = [NSURLSession sharedSession];
    
    // Image file and parameters
    NSData *imageData = UIImageJPEGRepresentation([UIImage imageNamed:@"yourImage"], 0.6);
    NSDictionary *parametersDictionary = [NSDictionary dictionaryWithObjectsAndKeys:
                           @"yourKey", @"apikey",
                           @"True", @"isOverlayRequired",
                           @"eng", @"language", nil];
    
    // Create multipart form body
    NSData *data = [self createBodyWithBoundary:boundary
                                     parameters:parametersDictionary
                                      imageData:imageData
                                       filename:@"yourImage.jpg"];
    
    [request setHTTPBody:data];
    
    // Start data session
    NSURLSessionDataTask *task = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
        NSError* myError;
        NSDictionary *result = [NSJSONSerialization JSONObjectWithData:data
                                                               options:kNilOptions
                                                                 error:&myError];
        // Handle result
    }];
    [task resume];
}
    
- (NSData *) createBodyWithBoundary:(NSString *)boundary parameters:(NSDictionary *)parameters imageData:(NSData*)data filename:(NSString *)filename
{
    NSMutableData *body = [NSMutableData data];
    
    if (data) {
        [body appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
        [body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"; filename=\"%@\"\r\n", @"file", filename] dataUsingEncoding:NSUTF8StringEncoding]];
        [body appendData:[@"Content-Type: image/jpeg\r\n\r\n" dataUsingEncoding:NSUTF8StringEncoding]];
        [body appendData:data];
        [body appendData:[[NSString stringWithFormat:@"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
    }
    
    for (id key in parameters.allKeys) {
        [body appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
        [body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"\r\n\r\n", key] dataUsingEncoding:NSUTF8StringEncoding]];
        [body appendData:[[NSString stringWithFormat:@"%@\r\n", parameters[key]] dataUsingEncoding:NSUTF8StringEncoding]];
    }
    
    [body appendData:[[NSString stringWithFormat:@"--%@--\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]];
    
    return body;
}