Canon VB-730F Mk II Operation Manual page 128

[Enable in H.264(1)]
Select [Enable] to lower video quality of outside areas set with [Specified Area] in H.264(1) video.
[Enable in H.264(2)]
Select [Enable] to lower video quality of outside areas set with [Specified Area] in H.264(2) video.
[Data Size Reduction Level]
Set the data size reduction level for the outside area of [Specified Area]. If you select [Low], the data size reduction effect is
lower. If you select [High], the data size reduction effect is higher.
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