Instead of manually selecting input streams to be transcoded, you can define templates with rules for automatic transcoding of input streams according to the settings of a pre-defined Transcoding Template. Every time a new input stream, which matches the conditions of the template, is added, it will be automatically transcoded into the transcoded streams defined in the template's settings. The input streams are identified by system according to naming patterns.
The transcoding profiles used in the transcoding templates have to be created in advance (for more information see Creating New Profiles).
To create a new transcoding template:
- Click the Inputs tab at the top of the Zixi Broadcaster administrative screen.
- In the Menu bar, click the Templates (
) button.
The Transcoding Templates window is displayed:
- Next to Input ID Patterns, click
to define a new template.
The following window is displayed:
- In the Input ID pattern field, enter a pattern for the Stream ID of the input stream that will be automatically transcoded. This pattern will be used to identify the input stream and can include variables that are marked with the "$" sign followed by a number (e.g. $1, $2, etc.) and/or with an asterisk "*" wildcard. The patterns should also include a part of the string that requires an exact match. For example, the pattern "$1_stream_$2kbps" will match an input stream "talk_show_stream_600kbps".
- Click Apply.
The new template is added to the list of transcoding templates. However, the transcoding will not be active until you define transcoded stream rules.
- Select the newly created template and click the button, located at the right-hand corner to define a transcoded stream rule.
The Transcode <template_name> window opens:
- Enter the unique Stream ID. for the transcoded stream.
- In the Max Outputs field, define the maximal number of outputs that can be connected to the stream.
- Under Stream Parameters, select the desired Video Profile and/or Audio Profile that you have configured. If you have not configured a video or audio profile you can select Keep original stream. In this case the video or audio input will not be transcoded. You can also set specific transcoding parameters for the specific stream (see table below for more details).
- Click OK.
The transcoded input stream rule is created and appears as follows:
If an input stream enters Zixi Broadcaster and matches the Input ID pattern, it will be transcoded according to all the transcoded input stream rules that were created.
Parameter | Description |
|---|---|
Video Profile | Select an existing profile or select Keep original stream if you do not wish to transcode the video stream. |
Audio Profile | Select an existing profile or select Keep original stream if you do not wish to transcode the audio stream. |
| Apply audio profile for all audio PIDs | Select this option if you want to re-encode all audio tracks using the same audio profile, instead of just the first audio track that is detected. |
| Output Type | Select one of the following output types. The outputs are configured as part of the transcoding process, so there is no need to create the Output from the Zixi Broadcaster Outputs screen:
|
Transport Stream Bitrate (Kbps) | Specify the bitrate of the transport stream. This parameter is optional. If you do not specify a TS Bitrate, the stream will be VBR. If you specify a bitrate, the stream will be CBR. |
Use Intel hardware acceleration (if available) | Select this checkbox to use hardware acceleration component if it has been installed. |
| Add RTP headers | Select this checkbox to add RTP headers to the stream. RTP adds a 12-byte header, which includes a sequence number and a timestamp that can be used to detect dropped packets. The sequence number in the RTP headers can be used to do automatic reordering and the timestamps can help overcome inter-packet gaps, also known as IAT (Inter Arrival Time). However, plain RTP does not feature error recovery or error protection. By default, the RTP headers (which include the timestamps and sequences) are being used on the input side, but then they are stripped off and they no longer propagate to outputs. |
Pass all PIDs | Select this checkbox to pass-through all non-transcoded PIDs. |
| Force I-Frames on SCTE-35 markers | |
| Copy Closed Captions | |
| Smoothing buffer [ms] | The Smoothing feature uses a buffer to time packets according to the stream's clock. This is useful when there are bursts in the rate in which the stream arrives. The smoothing features creates a queue in the buffer, allowing smoother entry into the Broadcaster. The Smoothing parameter defines the size of the buffer in Milliseconds. A larger the buffer enables smoother entry. However, it may influence the latency rate. |
| GPU | The GPU utilization threshold. If this limit is exceeded, the GPU indicator at the top of the screen will appear in red, and an alarm will be generated in the event log. Default: 0 |
| Crop Parameters | Select this checkbox to set the cropping parameters. |
| Cropping Mode | Set the units used for defining the crop. Options are: Pixels or Percentages. Note: Depending on the type of content, in some cases using different crop values for low resolution outputs might be appropriate. For example, if the content includes both video content and textual content, the text would not be readable at lower resolutions and thus might be better to exclude. Another use case for using different crop values for each output would be to slice a 360 or VR input video. |
| Left, Top | Specify the left and top positions for the crop. |
| Width x Height | Specify the width and height values for the crop. |
| Billing Codes | Billing codes are used to identify and differentiate traffic on a Zixi Broadcaster for billing purposes. When a billing code is added to a Source or Target, Zixi can track the traffic on that Broadcaster input or output separately from other inputs and outputs on the same Broadcaster. Billing codes are created by Zixi personnel on the Zixi Customer Portal for a particular organization. |
| Billing Code | Enter the billing code that corresponds to this stream. The relevant billing can be obtained from the organization that received the billing code from Zixi. |
| Billing password | Enter the password that corresponds to this billing code. |
Enable time shift | Select to enable delayed transmission. |
Maximum delay [hh:mm:ss] | Specify the time of the delayed transmission of this stream. Maximum: 24 hours. |
Transmit as multicast | Selecting this checkbox enables the transmission of this stream’s outputs as multicast. A Zixi receiver that will pull the stream will receive it in multicast. By default Zixi Broadcaster is configured to allow transparent fallback to unicast if it is out of the LAN. Requires enabling Multicast Pull in the Settings. This setting requires enabling Multicast Pool (Settings > Multicast Pool). |
| Enable multicast output on pull outputs | Selecting this checkbox will force the transmission of this stream only in multicast. |
Recording Parameters | |
Max recorded file duration [hours] | Specify the maximum time allotted for recording a video stream. Default: 2 hours |
Keep recorded files for [hours] | Specify the maximum time for storing the recording. Default: 0 hours |