[Mp4-tech] About level_prefix of cavlc!

[Gary Sullivan]

Jely et al,
What you saw in that paper was, most likely, based on the version of the
standard that included only the three original profiles (Baseline, Main,
and Extended).   See what subclauses A.2.1 through A.2.3 now say about
level_prefix in those profiles.
In the new FRExt profiles (High, High 10, High 4:2:2, and High 4:4:4),
the range of level_prefix is controlled only indirectly through the
limits on the range of values that are allowed in the scaling and
transformation processes (subclauses 8.5.8 through 8.5.11).  The actual
range that is possible will depend on such factors as transform type and
sample bit depth.
Best Regards,
Gary Sullivan
+> -----Original Message-----
+> From: mp4-tech-bounces lists.mpegif.org 
+> [mailto:mp4-tech-bounces lists.mpegif.org] On Behalf Of 
+> JelyZhu innosis.com.cn
+> Sent: Monday, September 12, 2023 10:20 PM
+> To: mp4-tech lists.mpegif.org
+> Subject: [Mp4-tech] About level_prefix of cavlc!
+> 
+> 
+> Hi experts,
+> 
+> I have a question about the range of level_prefix of cavlc.
+> 
+> In Table9-6 of the latest H.264 standard, level_prefix can 
+> be greater than
+> 15. But I have seen a paper in which level_prefix cannot be 
+> greater than
+> 15. I don't know what on earth the range of level_prefix is, 
+> [0,15] or any
+> else?
+> 
+> Thanks in advance.
+> 
+> Best Regards,
+> Jely
+> 
+> 
+> _______________________________________________
+> NOTE: Please use clear subject lines for your posts. Include 
+> [audio, [video], [systems], [general] or another 
+> apppropriate identifier to indicate the type of question you have.
+> 
+> Note: Conduct on the mailing list is subject to the 
+> Antitrust guidelines found at 
+> http://www.mpegif.org/public/documents/vault/mp-out-30042-Ant
+> itrust.php
+>