//  ViewController.m
#import "ViewController.h"
#import <WebKit/WebKit.h>
#import <CFNetwork/CFNetwork.h>

@interface ViewController ()
@end

@implementation ViewController

NSMutableData *_receivedData;	// buffer for accumulating data
#define END_MARKER_BYTES { 0xFF, 0xD9 }
static NSData *_endMarkerData = nil;

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- (IBAction)getVideo:(id)sender	// прием видеопотока по кнопке
{   NSString *finalURLcamera = @"http://"; NSString *urlIP = [_cameraIP text];	// IP-адрес камеры - в TextField'e cameraIP
    finalURLcamera = [finalURLcamera stringByAppendingString:urlIP];                // конструируем полный URL
    finalURLcamera = [finalURLcamera stringByAppendingString:@":554/video.mjpg"];
    
    NSURL *url = [NSURL URLWithString:finalURLcamera];
    NSURLRequest *requestURLcamera = [NSURLRequest requestWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:60.0];
    NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:requestURLcamera delegate:self];	// connecting
    
    uint8_t endMarker[2] = END_MARKER_BYTES;
    _endMarkerData = [[NSData alloc] initWithBytes:endMarker length:2];
}

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// ****************** прием видеопотока ****************
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{   if (!_receivedData) { _receivedData = [NSMutableData new]; }
    [_receivedData appendData:data];
    NSRange endRange = [_receivedData rangeOfData:_endMarkerData options:0
                                            range:NSMakeRange(0, _receivedData.length)];
    if (endRange.location == NSNotFound) { return; }
    @autoreleasepool
    {  UIImage *receivedImage = [UIImage imageWithData:_receivedData];
        if (receivedImage) { self.cameraWindow.image = receivedImage; }	// cameraWindow - это UIImageView
    }
    [_receivedData setLength:0];
}

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{    _receivedData = [[NSMutableData alloc] init]; }
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