Unity 2019.3 new SSAO

1. What happened
There are various issues relating to the new screen space occlusion.

Happens in unity 2019.2 and 2019.3

A few issues relating to SSAO:
1)Playing from the timeline. The shadows and occlusion does not resolve properly before the animation starts in the timeline or during playback - It will do one of the following:
has increased noise
creates a artifacts with shadows with a slight ghosting effect that resolves as the timeline progresses (not ideal)
2) Camera change creates a ghosting effect or does not resolve quick enough as items animate in the scene (we are using alembic)

Please note - all issues happen with MSAA at 8x too. The noise / artifacts is differnet but still undesirable.

Other useful info / opinion
We are testing HDRP to decide whether it will work well in production for rendering animations. Shadow resolution and high fidelity is important (not performance). Recording from the timelne will cause issues as we would require the SSAO to resolve almost instantly, or resolve prior to the timeline playing (for example, when using the recorder)
Ultimately, the new SSAO is not viable for high fidelity rendering from the timeline. It takes too long to resolve and there is ghosting with noise and artifacts. I understand there are limitations to the technique, however the older implementation (without the speculaor occlusion) worked better. I would expect to have at least the same quality or better with a new implementation.

2. How we can reproduce it using the example you attached
All issues can be found within the scene "5_Grace_1"

If performance is is low, turn off "---Recflection---" & "----LIghting---" in the heirarchy . Also feel free to lower the shadow resolution in the HDRP settings file (under settings). This does not impact any of the issues
The SSAO profile is found under ---- Volumes--->VOL AO Test in the hierarchy

Please load that scene and try each of the following steps bellow

1)PLaying from the timeline - Frame 0
Select the same timeline (5_Grace_Full)
Ensure the timeline is at frame 0
Press play on the timeline. There is terrible noise around the characters face as the mug is lowered (Frame 0 - 50).
AO or SO does not resolve quick enough.
The same issue happens in playback via the editor play button

2) Camera Change
Click on the timeline "5_Grace_Full"
Press play in the timeline
SSAO takes a while to resolve - Ghosting appears around the legs of the character (approx frame 360)
Similarly the SSO also takes a while resolve as the character runs past the display cabinet in the background (approx frame 445)
This is also simlar to SSR (approx frame 410 - 418)

If you move the scrubber (without pressing play) for example to frame 8 and let it resolve for 5 or 10 seconds, this is what we would be expecting once its resolved. If you press play again, the SSAO resets and and does not resolve quick enough. This would not be useful for any kind of rendering or recording.

License type: Pro