iOS Stream Recording

Example of iOS application for stream recording

This streamer can be used to publish and record WebRTC video stream on Web Call Server.

On the screenshot below (from left to right)

• a stream is being published
• stream publication is stopped and connection to server is closed

In the URL specified in the input field

• 192.168.2.107 is the address of the WCS server
• testStream is the stream name

Above the input field video from the camera is displayed. When publication is stopped, download link for the recording of the published stream is displayed.

Analyzing the example code

To analyze the code, let's take StreamRecording example, which is available here.

View class for the main view of the application: ViewController (header file ViewController.h; implementation file ViewController.m).

1. Import of API

code

#import <FPWCSApi2/FPWCSApi2.h>

2. Session creation and connecting to server

FPWCSApi2.createSession, FPWCSApi2Session.connect code

The options include:

• URL of WCS server
• appKey of internal server-side REST hook application (defaultApp)

- (FPWCSApi2Session *)connect {
    FPWCSApi2SessionOptions *options = [[FPWCSApi2SessionOptions alloc] init];
    url =[[NSURL alloc] initWithString:_connectUrl.text];
    options.urlServer = [NSString stringWithFormat:@"%@://%@:%@", url.scheme, url.host, url.port];
    streamName = [url.path.stringByDeletingPathExtension stringByReplacingOccurrencesOfString: @"/" withString:@""];
    options.appKey = @"defaultApp";
    NSError *error;
    FPWCSApi2Session *session = [FPWCSApi2 createSession:options error:&error];
    ...
    [session connect];
    return session;
}

3. Receiving the event confirming successful connection

FPWCSApi2Session.onConnected code

On this event, publishStream method is called to publish the stream

- (void)onConnected:(FPWCSApi2Session *)session {
    [self publishStream];
}

4. Stream publishing

FPWCSApi2Session.createStream, FPWCSApi2Stream.publish code

Object with the following stream options is passed to createStream method:

• stream name
• view to display video
• true for parameter record to enable stream recording
• video constraints for iPad

- (FPWCSApi2Stream *)publishStream {
    FPWCSApi2Session *session = [FPWCSApi2 getSessions][0];
    FPWCSApi2StreamOptions *options = [[FPWCSApi2StreamOptions alloc] init];
    options.name = streamName;
    options.display = _remoteDisplay;
    options.record = true;
    if ( UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad ) {
        options.constraints = [[FPWCSApi2MediaConstraints alloc] initWithAudio:YES videoWidth:640 videoHeight:480 videoFps:15];
    }
    NSError *error;
    FPWCSApi2Stream *stream = [session createStream:options error:&error];
    ...
    if(![stream publish:&error]) {
        UIAlertController * alert = [UIAlertController
                                     alertControllerWithTitle:@"Failed to publish"
                                     message:error.localizedDescription
                                     preferredStyle:UIAlertControllerStyleAlert];

        UIAlertAction* okButton = [UIAlertAction
                                   actionWithTitle:@"Ok"
                                   style:UIAlertActionStyleDefault
                                   handler:^(UIAlertAction * action) {
                                       [session disconnect];
                                   }];

        [alert addAction:okButton];
        [self presentViewController:alert animated:YES completion:nil];
    }
    return stream;
}

5. Receiving the event confirming successful stream publishing

FPWCSApi2Stream.onPublishing code

When the stream is published, FPWCSApi2Stream.getRecordName is used to get the filename of the stream recording

- (void)onPublishing:(FPWCSApi2Stream *)stream {
    [_startButton setTitle:@"STOP" forState:UIControlStateNormal];
    [self changeViewState:_startButton enabled:YES];
    recordName = [stream getRecordName];
}

6. Disconnection

FPWCSApi2Session.disconnect code

- (void)startButton:(UIButton *)button {
    [self changeViewState:button enabled:NO];
    if ([button.titleLabel.text isEqualToString:@"STOP"]) {
        if ([FPWCSApi2 getSessions].count) {
            FPWCSApi2Session *session = [FPWCSApi2 getSessions][0];
            NSLog(@"Disconnect session with server %@", [session getServerUrl]);
            [session disconnect];
        } else {
            NSLog(@"Nothing to disconnect");
            [self onDisconnected];
        }
    } else {
        [self changeViewState:_connectUrl enabled:NO];
        [self connect];
    }
}

7. Receiving the event confirming successful disconnection

FPWCSApi2Session.onDisconnected code

On this event, the record file download link is formed, and ViewController.playVideo method is called to play the record

- (void)onDisconnected {
    [self changeViewState:_connectUrl enabled:YES];
    [self onUnpublished];
    if (url && recordName) {
//        NSString *urlString = @"http://www.sample-videos.com/video/mp4/720/big_buck_bunny_720p_1mb.mp4";
        NSString *urlString = [NSString stringWithFormat:@"http://%@:9091/client/records/%@", url.host, recordName];
        _recordLink.text = urlString;
        [self playVideo: urlString];
    }
}

8. Record playback

AVPlayer.play code

- (void)playVideo:(NSString *)urlString {
    NSURL *url = [NSURL URLWithString:urlString];
    AVURLAsset *movieAsset = [AVURLAsset URLAssetWithURL:url options:nil];
    [movieAsset.resourceLoader setDelegate:self queue:dispatch_get_main_queue()];

    AVPlayerItem *playerItem = [AVPlayerItem playerItemWithAsset:movieAsset];
    _player = [AVPlayer playerWithPlayerItem:playerItem];
    _playerViewController.player = _player;
    [_player play];
}