public String getSubgopLength() {
        return this.subgopLength;
    }
Relates to the GOP structure. If you do not know what GOP is, use the default. FIXED: Set the number of B-frames
in each sub-GOP to the value in gopNumBFrames. DYNAMIC: Let MediaLive optimize the number of B-frames in each
sub-GOP, to improve visual quality.

@return Relates to the GOP structure. If you do not know what GOP is, use the default. FIXED: Set the number of
        B-frames in each sub-GOP to the value in gopNumBFrames. DYNAMIC: Let MediaLive optimize the number of
        B-frames in each sub-GOP, to improve visual quality.
@see Mpeg2SubGopLength
aws-java-sdk-medialive/src/main/java/com/amazonaws/services/medialive/model/Mpeg2Settings.java