The only place where chroma key would help is a stationary flag getting partially obscured by a moving object. Otherwise, it’s more effective to just paste a drawing of all the hakenkreuze over each frame using decades-old subtitling technology. However, even stationary shots with non-moving flags (where the drawing can be reused) could be problematic because of picture jitter.
So what I meant was: the technique they would need was probably not chroma key.
If you check out the Wikipedia article for Chroma Key, it’s not as far fetched as you might think.
This is not chroma key.
It’s not - but not necessarily because the technology wasn’t there
The only place where chroma key would help is a stationary flag getting partially obscured by a moving object. Otherwise, it’s more effective to just paste a drawing of all the hakenkreuze over each frame using decades-old subtitling technology. However, even stationary shots with non-moving flags (where the drawing can be reused) could be problematic because of picture jitter.
So what I meant was: the technique they would need was probably not chroma key.