[MPlayer-users] Mencoder xvid feature request, or not work as expected.

[한원섭]

I have request/report about sth 'zones' option in xvid encoder. Currently this option is incomplete, or not work as expected. Here is the document of this option for xvid_encraw 1.3.5.


 -zones start,mode,value[,options][/start,mode,value[,options]]...

 Parameters of a zone use the comma (,) as a delimiter. Multiple zones are
 separated by a slash (/). The end of each zone is defined by either the start
 of the following zone or the last frame of the input file.

 start     : start frame of the zone
 mode      : weight zone = w, quantizer zone = q
 value     : depending on mode either the zone's weight or quantizer
 options   : enable certain encoder features for the zone. Each feature is
             represented by a single letter. An integer number stands for
             b-frame sensitivity. To enable multiple features at the same time
             combine the appropriate symbols without any delimiting characters.
             K = begin with keyframe
             O = enable chroma optimizer
             G = greyscale encoding
             C = cartoon mode
       integer = b-frame sensitivity

 Example:
  to create a first zone starting at frame 0 with weight 1.0, all options
  enabled and b-frame sensitivity -5, and a second zone starting at frame 1000
  with constant quant 4 and no options enabled you would use the -zones option
  like this:

  -zones 0,w,1.0,-5KOGC/1000,q,4


zones options is work as expected on xvid_encraw. Mencoder uses same xvidcore 1.3.5 so this option should be available as it is I believe. but currently, Seems 'zones' on Mencoder xvid doesn't really parse [,options], '-5KOGC' part in Example section is ignored. As a result can not use full feature of it.

Most importantly, This is the only option available to forcing specific frame as keyframe. Without this option There are no way to align keyframes, such as each frame of chapter start points. The other way to make keyframe obeys chapter points is splitting videos by chapter, encode them separately and concat. It's really inconvenient. So I really hope if This option can be fully featured in Mencoder.