Filter a Track

You can filter a track to extract records that match particular conditions. For example, you can:

  • extract records from OCR analysis results that match or contain a specified string
  • extract records from a speech-to-text task that match or contain a specified string
  • extract records from a face detection task that describe faces that appear in a particular region of the frame
  • extract records from an object recognition task that match a specific object

To filter a track

  1. Create a new configuration to send to Media Server with the process action, or open an existing configuration that you want to modify.

  2. In the [Session] section, add a new task by setting the EngineN parameter. You can give the task any name, for example:

    [Session]
    Engine0=Ingest
    ...
    Engine5=Weather
  3. Create a new configuration section to contain the task settings, and set the following parameters:

    Type The ESP engine to use. Set this parameter to filter.
    Input The output track, produced by another Media Server task, that you want to filter.
  4. Set one of the following parameters to specify how the input track is filtered:

    RequiredString A string that a record must match to be included in the output track. (The input track must contain text data).
    RequiredSubString A string that a record must contain to be included in the output track. (The input track must contain text data).
    LuaScript The name of a Lua script that defines conditions that a record must meet in order to be included in the output track from the ESP engine. For more information, see Write a Lua Script for an ESP Engine.
  5. Save and close the configuration file. OpenText recommends that you save your configuration files in the location specified by the ConfigDirectory parameter.

Example

The following configuration produces a new track called Weather.Output. This track only contains records that include the word "weather".

[Weather]
Type=filter
Input=speechtotext.result
RequiredSubString=weather