frame number 1836: frame00000420.icpf: Found colorMatrix = UNKNOWN but expecting colorMatrix = BT_709
When indexing the ProRes file our system indicates that consecutive ProRes images did not keep a consistent color matrix (Rec_601/709). This is usually the result of data corruption having occurred before or during delivery. The error message provides the affected frame number, along with the value detected, and the expected value.
There is a multi-step process for resolving this issue:
Review the highlighted frame, step through a few frames both forwards and backwards up to a few frames on each side. Data corruption may manifest visually as a green or grey block, or may have active picture from the wrong frame.
If no issue is seen at this point, render out a small clip including a few seconds before and after the highlighted frame. On occasion data corruption may only manifest visually after another level of compression has been applied to it.
If you are able to see the issue after either step, then you have confirmed that data corruption is present within your source file. The issue can only be corrected by finding another source which is unaffected by the issue. When seeking other file based sources from your internal systems or archive please generate an MD5 checksum of the replacement to make sure it does not match the MD5 checksum of the rejected file.
If after these steps you still see no issues please reach out to your Netflix representative by commenting on the Source Request in Backlot.