You can use the WowzaConfig class in the Wowza GoCoder™ SDK for iOS to configure properties for a live streaming broadcast. There are three primary categories of properties: video, audio, and connection parameters for the Wowza Streaming Cloud™ service and Wowza Streaming Engine™ media server software.
Contents
Configure the stream parameters Use the configuration presets
Configure the stream parameters
Configure the video
Use the following properties to configure the video stream:
| Parameter | Description |
| videoFrameSize | The video resolution (width by height) in pixels. The default value is 640x480. |
| videoFrameRate | The number of frames per second (fps). The default value is 30. |
| videoKeyFrameInterval | The number of frames between keyframe insertions. The default value is 30. |
| videoBitate | The video bitrate in bits per second (bps). The default value is 1500. |
The following example demonstrates how to use the video parameters.
// Get a copy of the active config WowzaConfig broadcastConfig = self.goCoder.config; // Set the frame rate to 15 fps broadcastConfig.videoFrameRate = 15; // Set the keyframe interval to 10 frames broadcastConfig.videoKeyFrameInterval = 10; // Set the bitrate to 2.5 kbps broadcastConfig.videoBitrate = 2500; // Update the active config self.goCoder.config = broadcastConfig;
Configure the audio
Use the following properties to configure the audio stream:
| Parameter | Description |
| audioSampleRate | The audio sample rate in hertz (Hz). The default value is 44100. |
| audioChannels | The number of audio channels. The default value is 2. |
| audioBitrate | The audio bitrate in bits per second (bps). The default value is 64000. |
The following example demonstrates how to use the audio parameters.
// Get a copy of the active config WowzaConfig broadcastConfig = self.goCoder.config; // Set the sample rate to 22.1 kHz broadcastConfig.audioSampleRate = 22100; // Update the active config self.goCoder.config = broadcastConfig;
Configure the connection parameters
Use the following properties to configure the connection to your Wowza Streaming Engine server or the Wowza Streaming Cloud service:
| Parameter | Description |
| hostAddress | The domain name or IP address of the destination. There isn't a default value. |
| portNumber | The port number for the Wowza Streaming Engine server. The default value is 1935. |
| applicationName | The name of the destination live streaming application. The default value is live. |
| streamName | The name of the live stream that you're broadcasting. The default value is myStream. |
| username | (If your application requires it) the source authentication username. There isn't a default value. |
| password | (If your application requires it) the password associated with the source authentication username. There isn't a default value. |
The following example demonstrates how to use the connection parameters.
// Get a copy of the active config WowzaConfig broadcastConfig = self.goCoder.config; // Set the hostname broadcastConfig.hostAddress = @"live.someserver.net"; // Set the name of the stream broadcastConfig.streamName = @"someStreamName"; // Update the active config self.goCoder.config = broadcastConfig;
Use configuration presets
Alternatively, you can preconfigure your broadcast with the following presets, which are designed for common frame sizes:
| Preset Identifier | Video Frame Size | Vide Bitrate |
| WZFrameSizePreset352x288 | 352x288 | 280 Kbps |
| WZFrameSizePreset640x480 | 640x480 | 1.5 Mbps |
| WZFrameSizePreset1280x720 (720p) | 1280x720 | 3.75 Mbps |
| WZFrameSizePreset1920x1080 (1080p) | 1920x1080 | 5 Mbps |
| WZFrameSizePreset3840x2160 (4K UHD) | 3840x2160 | 8 Mbps |
The following example demonstrates how to use a preset configuration.
// Get a copy of the active config WowzaConfig broadcastConfig = self.goCoder.config; // Set the defaults for 720p video [broadcastConfig loadPreset:WZFrameSizePreset1280x720]; // Update the active config self.goCoder.config = broadcastConfig;
If you're having problems or want to discuss this article, post in our forum.
