Export Fail for Multicam content that has been field interpreted.

[Leosk]

We have discovered a major export bug that effects all available versions of Premiere 22 & 23 when working with interpretted PsF content into progressive. The workflow as follows;

Multiple records in 1080/25PsF ProRes 422 are ingested, interpreted to progressive then built into progressive multicam clips, between 9 and 35 cameras then cut in a multicam Prores 422 25P sequence. Cuts applied, other media added etc.

If trying to export to the same codec Prem starts off very slow (ie indicates at 48 minute export for what is a 2 minute render all action) then eventually crashes. Having tried this across multiple M1 Max and iMac Pro workstations we realised the only fix is to transcode on export, ie export as 422 HQ, which takes a couple of minutes. I havent explored using a software only engine but performance is key; 12 editors and 4 assists in a high demand/fast delivery broadcast environment.

[Leosk]

I should also add that we use a companion/attached proxy workflow with proxies in Prores 422 proxy that are built in media encoder also using the interpret option. These have BITC to catch any mistakes in attachment and must be made in media encoder to enable multiple machine encoding. However I believe this has no bearing as the problem still occurs with proxies detached.

Projects are organised within a production enabling them to be kept small, and this problem still remains in a fully flatten and very simple sequence of less than 5 minutes with only 15 cuts in and all fx removed.