Duplicate PES PTS values at start?

[gconnery]

Using the Mux panel with an AVC elementary stream and an MPEG-1 audio stream to produce an MPEG-2 SPTS, if I look at the resulting transport stream I see:

A PAT at packet 0.

A PMT at packet 1.

A PES header at packet 2 with PTS 22172, and DTS 19169
followed by a SEQ, VUI, PIC, SEI, and finally an IDR-SLICE for an I-frame.
(p.s. packet 2 should really have a discontinuity flag set to force the PCR to be loaded)

A PES header at packet 27 followed by a P slice.  Problem is the PTS on this frame is also  22172.  In theory only one of these frames should display as a result of this collision.

The next frame (a P) follows at packet 28 with a PTS of 25175, which is fine, but a DTS of 22172, which since it conflicts with the DTS of the previous frame, means this frame might not get decoded.  Which would be bad.

This appears to just be a startup problem, since things work fine after that.

[Vovs]

It seems you are right about PTS issue at packet 27. We'll try to fix this issue in the multiplexer. But I can't agree with you regarding next point of your post.

In fact packet 28 has a PTS of 25175 and a DTS of 22172 but previous one has a DTS 19170.

[Vovs]

It seems the duplicate PES PTS values issue is related with interlace stream support.

[gconnery]

I think I saw this with a progressive stream.  Please check.