Alpha in DXV3 from After Effects via Adobe Media Encoder

[Frischvergiftung]

We rendered a bunch of Clips as PNG-Sequences that we would like to encode as MOV with DXV 3 codec // HQ with alpha. while it works easily by importing into AE then rendering from there, it doesnt if we render via Media Encoder. The benefit of that would be that we can render in the background.

No file thats being produced via AME has an alpha channel. either setting HQ/LO/ALPHA. verified thers no alpha channel in AE and in Arena. doesnt have to do with the premultiplied or straight setting of the clip in arena either, that buttons is simply not there when i play a file from AME.

also tried rendering in 32 bit from AME - no alpha. also tried importing the PNG sequence directly into AME and rendering that - no alpha.

also read the other threads here on the topic, tried all that.

why can AME not produce an alpha channel in DXV3?

any ideas??

[Joris]

I'm sorry to say I couldn't reproduce your problem. Here's what I did:

- import a PNG sequence with alpha into After Effects
- create a comp out of it by dragging the image sequence over the new comp icon
- tell that comp to render through AME, via File > Export> Using AME Queue
- in AME, use DXV3 HQ with Alpha, all settings at Match Source, Render at Maximum Depth checked, set to 32 bit depth.

The resulting file shows as the correct DXV3 HQ with alpha setting. The only thing is that the premult option is wrongly interpreting it as premultiplied, even though it's straight.

This is on Mac, CC2015.

Maybe you can see something I'm missing?

[Oaktown]

Are you able to render your PNG sequence with Alpha in AME using another codec?

Also, have you tried uninstalling and reinstalling the DXV codecs and/or AME?

[Frischvergiftung]

thanks for your answers, had no time yet, will try and report!

[Frischvergiftung]

it works now... i think i simply got the DXV3 setting wrong in AME. sometimes trying again in the morning and not after a long working day proves the best idea...

the difference between checking "render at maximum depth" and not doing so decideds if the alpha channel is integrated or straight right? which option in accordance with what setting of alpha interpretation in resolume will yield the fastest performance?

thanks for the answers so far!

[Joris]

As far as I know, the "Render at Maximum Depth" setting has nothing to do with alpha. I think it's for compatibility with rendering to 10 bit codecs from Premiere, which is only 8 bit.

The only setting to do with alpha is the option to switch between 24 bit (no alpha) and 32 bit (with alpha).

There is no performance difference between straight and premultiplied alpha in Resolume. We make all our content premultiplied, simply because that is the default interpretation in Resolume.