Test vectors

Test vectors are grouped with a common prefix. For example test_000012 has several files associated with it.

• Metadata describing the test vector:test_000012.textproto.
• Standalone IAMF bitstream: test_000012.iamf.
• Fragmented MP4 file: test_000012_f.mp4.
• Standalone MP4 file: test_000012_s.mp4.
• Rendered WAV file (per mix_presentation_id x, sub mix index y, layout index z): test_000012_rendered_id_x_sub_mix_y_layout_z.wav

.textproto files

Theses file describe metadata about the test vector to encode an IA Sequence.

• is_valid: True when the encoder can produce an IA Sequence where all mixes would be understood by a compliant decoder. False when one or more mixes exercise fields or features which would cause mixes to be ignored.
• is_valid_to_decode: True when an IAMF-compliant decoder could decode at least one mix of the associated IA Sequence (“should-pass”). False when all mixes are non-conformant and may fail to be decoded (“should-fail”). The IAMF spec does not specify what happens when requirements are violated; a robust system may still attempt to process and create output for “should-fail” tests.
• human_readable_descriptions: A short description of what is being tested and why.
• mp4_fixed_timestamp: The timestamp within the MP4 file. Can be safely ignored.
• primary_tested_spec_sections: A list of the main sections being tested. In the form X.Y.Z/class_or_field_name to represent the class_or_field_name in the IAMF specification Section X.Y.Z is being tested.
• base_test: The recommended textproto to diff against.
• Other fields refer to the OBUs and data within the test vector.

Input WAV files

Test vectors may have multiple substreams with several input .wav files. These .wav files may be shared with other test vectors. The .textproto file has a section which input wav file associated with each substream.

Summary

Output WAV files

Output wav files are based on the layout in the mix presentation. Typically the ordering of channels is based on the related ITU-2051-3 layout.