[MPlayer-dev-eng] -lameopts: conflicting documentation and code?

[Charles Wilcox]

Okay, it's kindof trivial, but here it is.

All that is changed is the removal of the erroneous "+1" onto the value of
'lame_param_quality'; I also changed the commented example VBR quality
values appropriately.

Let me know if you have any questions about this,

 -- Charles Wilcox

On Thu, 19 Feb 2004, Diego Biurrun wrote:

> Charles Wilcox writes:
>  > The man page and HTML documentation say that they q= value can be set from
>  > 0 to 9, the equivalent of the same option of Lame.  However, this is not
>  > the case of what happens.  mencoder.c:986 has a line that adds one onto
>  > the value specified before it is sent off to libmp3lame.  This is
>  > complicated by the fact that cfg-mencoder.h:25 says that the input is
>  > indeed in the 0 to 9 range.  Also, the code makes no effort to check to
>  > see if the resulting value is 10, which is an incorrect value to pass on.
>  >
>  > Considering all the docs imply this option should match up to what LAME
>  > would normally take, could this possibly be a error in the code?  Taking a
>  > cursory glance at the lame code in frontend/parse.c:1626, it does not alter
>  > the value before it calls lame_set_VBR_q.
>  >
>  > Sorry, I'm just learning how to use Mencoder, but I've used Lame
>  > extensively, and this inconsistency confuses me.  Is there a reason it it
>  > like this?  If so, there is no warning to those who'd assume that the VBR
>  > quality numbers mean the same thing.  (That, and it just doesn't make any
>  > sense to me.)  If this is a mistake... wow, I guess not many people
>  > specify -lameopts to have caught this.
>
> Sounds like you found a real bug, could you come up with a patch that
> fixes it, please?
> Thanks
>
> Diego
>
>
-------------- next part --------------
--- MPlayer-1.0pre3/mencoder.c	2003-12-08 16:33:31.000000000 -0500
+++ /usr/local/src/MPlayer-1.0pre3/mencoder.c	2004-02-19 00:07:31.000000000 -0500
@@ -983,7 +983,7 @@
 lame_set_quality(lame,lame_param_algqual); // 0 = best q
 if(lame_param_vbr){  // VBR:
     lame_set_VBR(lame,lame_param_vbr); // vbr mode
-    lame_set_VBR_q(lame,lame_param_quality+1); // 1 = best vbr q  6=~128k
+    lame_set_VBR_q(lame,lame_param_quality); // 0 = best vbr q  5=~128k
     if(lame_param_br>0) lame_set_VBR_mean_bitrate_kbps(lame,lame_param_br);
 } else {    // CBR:
     if(lame_param_br>0) lame_set_brate(lame,lame_param_br);