[Bug] MP4Box DASH generation with H.265 Content Conformance Issues [sf#327]

[rbouqueau]

Reported by diegosuarez on 2014-08-20 09:20 UTC
Dear all,

I have generated DASH content with MP4Box based on H.265 video (x265 in FFmpeg).
MP4Box - GPAC version 0.5.1-DEV-rev5322 is being used, running on Windows 7 32 bits.

The conformance test of the video representations obtained gave the following issues:

Section 6.3.4.3. of ISO/IEC 23009-1:2012(E): If 'sidx' is present in a Media Segment, the first 'sidx' box shall document the entire Segment. Violated for Media Segment 1. Segment duration 596.333333, Sidx documents 597.208333 for track 1, diff 0.875000.

Referenced moof earliest_presentation_time 10.291667 does not match to reference EPT 10.416667 for sidx number 1 at reference count 1.

SAP found with presentation time 12.000000 lesser than the declared SAP time 12.125000 (SAP_delta_time 0.000000), for sidx number 1 at reference count 2; first SAP shall be signalled as per Section 8.16.3.3 of ISO/IEC 14496-12 4th edition.

starts_with_SAP declared but the first sample's composition time does not match, for sidx number 1 at reference count 2 (checking sample 1 of trun 1, traf 1, moof 3).

Referenced track duration 10.291667 of track 1 does not match to subsegment_duration 10.416667 for leaf with EPT 0.000000, difference 1.250000e-001, threshold 8.138021e-005 (Leaf count 1).

The command used was:

MP4Box -dash 5000 -profile onDemand -rap -frag-rap -url-template -out
C:\xampp\htdocs\Dashcontent\BBB_H265\BBB_OnDemand_H265.mpd -segment-name %s_ -segment-ext mp4
~\ContentSources\bbb_720p_2000k_H265.mp4 ~\ContentSources\bbb_720p_1000k_H265.mp4
~\ContentSources\bbb_audio_32k.mp4

I would appreciate your comments related to this issue.

Thanks in advance!

Kind regards,

Diego Suarez

[rbouqueau]

Commented by rbouqueau on 2014-08-20 15:30 UTC
Hi Diego,

We are aware of this and plan to investigate when we find time. However you'll notice these are just warnings about imprecise timings and should not prevent your content to play.

Just for my knowledge, have you run the conformance checker on an equivalent stream with x264?

Romain

[rbouqueau]

Commented by diegosuarez on 2014-08-20 16:41 UTC
Hi Roman,

Yes. Using the same content but encoding it with H.264 gives no conformance issues.

Kind regards,

Diego