TEST_CONFIG.md

Test Configuration

There are 2 configuration files for the tests: 1) test-config.json includes the tests paramters as defined in the DPC Test specification and 2) generated/tests.json which includes information extracted from the MPD of the audio/video streams used in the tests. The structure of both configutation files is described in this document.

test-config.json

To configure the tests, the test-config.json may be used to specify test parameters. The parameters are scoped on three different levels: Globally, template based or test specific.

When specifying a parameter globally, it is used by all tests that don't have the parameter specified in either their template or specific test. Global parameters are defined in the all object in the test-config.json:

{
  "all": {
    "parameter1": "value1",
    "parameter2": "value2"
  }
}

When specifying a parameter for a test template, it will override corresponding global parameter definitions. It will be ignored, if it is defined test specific. Template based parameters are defined in an object with the template file name as key:

{
  "sequential-track-playback.html": {
    "parameter1": "value1",
    "parameter2": "value2"
  }
}

When specifying a parameter for a specific test, it will override corresponding global and template based parameter definitions. Test specific parameters are defined in an object with the specific tests file path relative to the server root as key:

{
  "Folder2/sequential-playback-of-encrypted-and-non-encrypted-baseline-content__ToS_MultiRate_fragmented__ToS_HEAACv2_fragmented.html": {
    "parameter1": "value1",
    "parameter2": "value2"
  }
}

Test Parameters

name	description
duration	The duration of the video in seconds.
loading	Describes the order in which to load segments. Provides the CMAF Fragment number that is loaded at step i, constrained such that (MAX(i-loading[i]) + MAX(loading[i]-i)) * MAX(df[k,i]) < max_buffer_duration. For example: [3, 2, 1, 6, 5, 4, 9, 8, 7]
min_buffer_duration	Expresses the minimum buffer that the Source Buffer maintains in the playback in ms.
playout	A mapping of segments from a specific representation and switching set to the segments being loaded into the video buffer. An array of triples defines switching set number, representation number and segment number for the respective segment in the video buffer. The first segment to load is defined by the first element, the second segment by the second element and so one. Example: [[1, 2, 1], [1, 2, 2], [1, 2, 3], ...]
random_access_fragment	Integer number of the fragment to skip to before start of buffering.
random_access_time	Time in seconds to skip to before start of buffering. Can be a floating point number.
total_representations	The total count of representations in the test vector.
ts_max	The maximum permitted startup delay in ms.
key_id	Key ID of the encrypted content.
content_key	Content key of the encrypted content.

generated/tests.json

The generated/tests.json is auto-generated via the generate-tests.py and should not be edited. It includes information about the test streams defined in tests.csv. The example below shows an example of a single entry in the tests.json.

{
    "tests": { 
        "d9666abb4a59ca7c6ad8bb8c9b8c0377": {
            "path": "avc_15_30_60-2021-09-09-online/sequential-track-playback__t1.html",
            "video": [
                "https://dash.akamaized.net/WAVE/vectors/2021-09-09/avc_sets/15_30_60/t1/stream.mpd"
            ],
            "audio": [],
            "code": "sequential-track-playback.html",
            "switchingSets": {
                "video": [
                    {
                        "cmaf_track_duration": "PT0H1M0.000S",
                        "fragment_duration": "PT0H0M2.016S",
                        "representations": {
                            "2": {
                                "period": 1,
                                "duration": 60,
                                "type": "video",
                                "frame_rate": "30",
                                "fragment_duration": 2.0
                            }
                        }
                    }
                ],
                "audio": []
            }
        },
        ...
    }
}

This is a brief description of the main elements in the example above:

• tests: the root element of the configuration object. It includes all tests declared in tests.csv.
  • d9666abb4a59ca7c6ad8bb8c9b8c0377: The ID of the test. It is auto-generated by the test-generation script.

    • path: the path of the corresponding test file within the generated folder.

    • video: array of the MPD URLs of video switching sets declared in the tests.csv

    • audio: array of the MPD URLs of audio switching sets declared in the tests.csv

    • switchingSets: includes video and audio switching sets declared in the tests.csv

      • video/audio: array that includes details about the video/audio switching sets extracted form the corresponding MPDs. Each item in the array represents a video switching set with the following properties (all values are extracted from the MPD):
      • cmaf_track_duration: the CMAF Track duration extracted from the corresponding audio or video MPD
      • fragment_duration: the fragment duration extracted from the corresponding audio or video MPD
      • representations: the audio or video representations extracted from the corresponding audio or video MPD. Each representation includes the following properties:
        • period: the period index associated with the representation. The index of the first period is 1.
        • duration: the duration of the representation in seconds.
        • type (Deprecated): it is always video for video representations and audio representations.
        • frame_rate: the frame rate.
        • fragment_duration: the fragment duration in seconds.