Test Content different codecs for Tests 8.15 and 8.16

[louaybassbouss]

DPCAT Tests 8.15 Source Buffer Re-Initialization (without changeType) and 8.16 Source Buffer Re-Initialization (with changeType) require content in different 2 codecs. For video, we have AVC so we need content in a different codec e.g HEVC and/or AV1. this related comment from @jpiesing related to this issue may help (copied from the google document):

For video, the obvious test content requirement is HEVC / AVC but any HEVC stream would do I think? For audio, the obvious one would be multi-channel to stereo or v.v.. Audio expert confirmation is required.

@FritzHeiden @dsilhavy FYI

[jpiesing]

Would an HEVC equivalent of stream T1 from AVC be good enough? 60s or 30s?

[louaybassbouss]

Would an HEVC equivalent of stream T1 from AVC be good enough?

yes

60s or 30s?

We are fine with both. For 30s content, we can play around 15s of content with codec1 and switch to codec2 for the remaining 30s 15s.

[rbouqueau]

Relates to cta-wave/dpctf-tests#85

[rbouqueau]

We need to review the encoding parameters and validate them: https://github.com/cta-wave/Test-Content-Generation/tree/master/Instructions

[rbouqueau]

Notes from today's call: AP@rbouqueau : @jpiesing suggests to define an equivalent to T1. @haudiobe suggests to validate it at the next DPTCF call next week.

[rbouqueau]

https://github.com/cta-wave/Test-Content-Generation/blob/master/Instructions/chh1.md

There is a table in the v1.39 document with an attempt to define the list of streams. Modifiers are:

• t1: basis (only in 25fps family?)
• t2: same as t1, no default flags / inband signalling (hev1 I guess)
• t3: same as t1, multiple chunks
• t4: same as t1, adding spatial/temporal pairs
• t5: same as t1, 60/1001 fractional frame rate family (?)

Do you feel like t1 to t4 cover all necessary options? For t5, do we want to cover different framerate families this way or generate each t1-t4 for each family (as the main script does) (note:the mezzanine source may be either TearsOfSteel or Croatia depending on the frame rate so mixing frame rate may not be trivial).

Compared to the existing matrix, we don't test the following options, please comment if you think they may be necessary:

• pic timing / vui timing
• different fragment durations
• different frame rate multipliers (e.g. 25 versus 12.5 and 50)

As a test I did add this folder with a t1 encoded in HEVC in all 3 fps families (including the cenc version, since I encoded using the main script). Just add 1,L1_1920x1080,TRUE,FALSE,hvc1,2,regular,duration,1920x1080,0.5,3500,30,chh1 to the Test-Content-Generation/switching_sets_single_track.csv file. This is exactly t1 from cfhd with a lower bitrate.

Can someone test this HEVC content?

[jpiesing]

There is a table in the v1.39 document with an attempt to define the list of streams.

I find the list of streams in 11.3.5 completely disconnected from the list of content options in 11.3.4. From the list of content options, I would have expected a table of comparable complexity to avc not the massively reduced one.

[jpiesing]

Looking further at 11.3.4, there are seem to be 5 content options that have more than one possible value or state.

1. Two options for default flags
   A: default_sample_flags, sample_flags and first_sample_flags neither set in the TrackFragmentHeaderBox nor TrackRunBox
   B: default_sample_flags, sample_flags and first_sample_flags set in the TrackFragmentHeaderBox and TrackRunBox
2. with (W) and without (W/O) picture timing SEI message
3. with (W) and without (W/O) with and without VUI timing information
4. Sample entry, see CMAF clause 9.4.1.2. Two options
   'hvc1' sample entry type (parameter sets within the CMAF Header)
   'hev1' sample entry type (parameter sets within the movie fragment header)
5. Fragments containing one or multiple moof/mdat pairs – two options
   A: Fragment is 1 chunk
   B: Fragment contains multiple chunks (p-frame to p-frame with b-frames)

There are also a number of options that can only have one value or where it's only proposed to test one value.

1. 7.5.17 Track Run Box ('trun') - v1 – combined with SAP type 1
2. 7.5.13 Edit List Box ('elst') - Absent
3. Initialization Constraints - Regular Switching Set, do not apply CMAF clause 7.3.4.2 and 9.2.11.4
4. CMAF Fragment durations - 2 seconds
5. B.2.4 - No SEI messages present.
6. B.3.3.2 - Single VPS.
7. B.3.3.3.2 - colour_description_flag set to 1.
8. B.3.3.3.2 - vui_time_scale and vui_num_units_in_tick set to constant.
9. B.5 - Settings according the requirements of the profile 'chh1' in Table B.1 of ISO/IEC 23000-19.

@Romain: Of the options that have more than one possibility, please can you say which is used for your test stream. Also please could you check that your test stream is compatible with the options where 11.3.4 proposes we only test one value.

[rbouqueau]

please could you check that your test stream is compatible with the options where 11.3.4 proposes we only test one value

I did. Eventually this is something we'll need to add to the WAVE verification script.

7.5.17 Track Run Box ('trun') - v1 – combined with SAP type 1

7.5.13 Edit List Box ('elst') - Absent
Initialization Constraints - Regular Switching Set, do not apply CMAF clause 7.3.4.2 and 9.2.11.4
CMAF Fragment durations - 2 seconds
B.3.3.2 - Single VPS.
B.3.3.3.2 - colour_description_flag set to 1.
B.5 - Settings according the requirements of the profile 'chh1' in Table B.1 of ISO/IEC 23000-19.

All ok.

B.2.4 - No SEI messages present.

Which kind of SEI? I guess from CMAF B.2.4 that we may be talking about payload types 137, 144 and 147 (related to color characteristics). In this sense it is ok.

B.3.3.3.2 - vui_time_scale and vui_num_units_in_tick set to constant.

While investigating these two are not ok (we should play with the encoder settings):

• NOK: vui_parameters_present_flag shall be set to 1
• NOK: is set to "hev1.2.4.L123.B0" or "hvc1.2.4.L123.B0" => current sample exposes hev1.2.4.L123.90

NB: I don't plan to fix the two last issues very soon unless told otherwise.

[rbouqueau]

Let me know when anyone was able to make a test, or if anything's missing to start testing.

[jpiesing]

@louaybassbouss ?