[Mp4-tech] question ME algorithm

[Tourapis Alexandros]

Dear Wang Hui,
There are two things you need to also check, the total number of bits, but also the total number of coded pictures. If your encoder skips pictures due to some conditions (rate control), then your results would not be as meaningful. In general you need to consider jointly bitrate and quality (PSNR). Also I am not aware which sequences you are testing. It is possible that if you are using a rather stationary sequence (e.g. container, akiyo etc) and coding your sequence at very low bitrate/high qp, that your results are very similar. On the other hand you will most likely see a big difference if you use high motion sequences. Are you also using an Rate Distortion Optimization within your software? 
Maybe this would also be useful to you since it discusses some of the algorithms implemented within the MPEG-4 OM, while it also mentions briefly the impact of intra decision:
A.M. Tourapis, O.C. Au, M.L. Liou, "Highly Efficient Predictive Zonal Algorithms for Fast Block-Matching Motion Estimation," in IEEE Transactions of Circuits and Systems for Video Technology, Vol 12, Issue 10, pp. 934-947, Oct. 2002
Kind regards,
Alexis
-----Original Message-----
From: Wang Hui [mailto:wangh china.com]
Sent: Sunday, December 07, 2023 3:36 AM
To: sunx
Cc: MP4-Tech
Subject: Re: [Mp4-tech] question ME algorithm
Dear sir:
Thank you for your email very much.
I have check the implementation carefully step by step,
It runs just as the algorithm description, TSS and
LOG method. 
I think the algorithm implementations are with no errors, but the
configuration and the subsequently processing may be wrong.
The all methods run without the 4MV support and half-pel search.
The search range is just same as the Full search.
I think that in the fast algorithms, the 'Intra' Macroblocks must
be more than that in the Full-search algorithm. how many are 'Intra'
Macroblocks  reasonalbe compare to the Full search method?
For I have no experiences about the ME algorithm implementations, 
I want to known in this case, what should be notice? and what does 
result in this type of errors?
best regards
Michael