Sync loss between 2 VPP components

[Pavel_P_1]

Hello,

I'm trying to make composition with video and ARGB picture on 2017r2 and have the problem.

This problem was described in other topic

https://software.intel.com/en-us/forums/intel-media-sdk/topic/562583

but there is no answer.

My target sheme of execution is:

(session 1: [decoder]) ---> (session 2: [VPP]) ---> (session 3: [composite VPP] ---> [encoder])
                                                                                (ARGB surface) ---^
I use separate session for [VPP] because there can be multiple variants of resolution and frame rate at the same time.

The result of encoding has the next glitches: flipping forward and back between frames.

I made some experiments with different variants of execution scheme (of course all session are connected), and here are the results:

scheme A (works fine):
(session 1: [decoder]) ---> (session 2: [composite VPP] ---> [encoder])
                                           (ARGB surface) ---^

scheme B (works fine):
(session 1: [decoder]) ---> (session 2: [composite VPP]) ---> (session 3: [encoder])
                                            (ARGB surface) ---^
                            
scheme C (works fine):
(session 1: [decoder]) ---> (session 2: [composite VPP]) ---> (session 3: [VPP] ---> [encoder])
                                            (ARGB surface) ---^
                            
scheme D (works with glitches):
(session 1: [decoder]) ---> (session 2: [composite VPP]) ---> (session 3: [VPP]) ---> (session 4: [encoder])
                                            (ARGB surface) ---^
                            
scheme E (works with glitches):
(session 1: [decoder] ---> [VPP]) ---> (session 2: [composite VPP] ---> [encoder])
                                                            (ARGB surface) ---^
                
All the next experiments I made are only with scheme E.

Video - timer, picture - png with dices.

Firstly, I added 250 surfaces to frame pool of [VPP]. Additionally I numbered empty surfaces using vertical light lines (number of light lines is the index of the surface) and received the following result:

https://www.youtube.com/watch?v=Wpuhqh-E_F0

It shows me that [composite VPP] uses surfaces that were taken from [VPP] but not filled with data yet. I.e. [composite VPP] can draw surfaces i and i-1 while [VPP] fills only surface i-1, and i-th is empty (or old).

So I added MFXVideoCORE_SyncOperation() in [VPP] and the glitches are gone. Because it's a rather slow solution, I'm searching for an alternative approach. I changed the direction of drawing surfaces (first - ARGB picture, second - frame from [VPP]) and glitches were gone again (without MFXVideoCORE_SyncOperation()). Next I made the following scheme: I draw the video frame, then ARGB picture, and third - invisible video frame from [VPP] again, and there were no glitches too (without MFXVideoCORE_SyncOperation()). But it's a slow solution too.

Right now i use frame buffer between (VPP) and (composite VPP) nodes. It's a queue with length = sync depth + 1. It solves the problem, but i think, we must find and fix the real error.

What else can I do to find a correct solution of my problem?

[Dmitry_E_Intel]

Hello Pavel,

Do you join the sessions by JoinSession() call?

Regards,

Dmitry

[Pavel_P_1]

Hello Dmitry.

Yes, i made connection between sessions by MFXJoinSession() function for all schemes, i tested.

Pavel.

[Dmitry_E_Intel]

Did it help?

[Pavel_P_1]

No, it gives no result. The glitches are still here. And in my previous comment, I tried to say, that I used MFX Join Session() in my schemes from the beginning.

[Dmitry_E_Intel]

Is it possible to share a reproducer? 

[Molinder__Herman]

Hello,

I've encountered this issue as well. I'm using "scheme E" as Pavel P describes it, with one exception. I'm rendering the [composite VPP] output directly to HDMI, thus no encoding.

Any updates on this issue? Any suggested work arounds?

BR
Herman