[MPlayer-DOCS] CVS: main/DOCS/xml/en mencoder.xml,1.39,1.40

[Guillaume Poirier]

Hi,

On Apr 1, 2005 1:39 AM, Diego Biurrun <diego at biurrun.de> wrote:
> On Fri, Mar 25, 2005 at 10:17:23PM +0100, Guillaume Poirier CVS wrote:
> >
> >  <para>
> > -  The main assumption of this guide is that you have no specific file size
> > -  constraints and have no problem giving up bits in exchange for quality.
> > -  While much of the information presented here is useful in any case, some
> > -  of it may work against you if you have a file size goal, such as fitting a
> > -  video on a CD.
> > +  If this seems to be too much for you, you should probably use one of the
> > +  many fine front-ends that are listed on our
> > +  <ulink url="http://mplayerhq.hu/homepage/design7/projects.html">related projects page</ulink>.
> > +  That way, you should be able to achieve high quality rips without too much
> > +  thinking, because most of those tools are designed to take clever decisions
> > +  for you.
> >  </para>
> 
> Hmm, why have you removed the above paragraph.  Is it not correct
> anymore?  I must admit I haven't read the MEncoder section in such a
> long time that I cannot tell for sure right now..

It's just because the assumption of unlimited size isn't true anymore.
This "improved" guide is intended to explain what make a rip look good
or not. I truly didn't like the idea of blindly using an arbitrary
high bitrate if it doesn't make sense to the user.
Now, I hope that this improved guide should make the user understand
what he/she can tweak to improve quality... or at least, that was my
goal.


> > +  audio track(s), so you should <link linkend="menc-feat-dvd-mpeg4-audio">rip
> > +  those</link> first.
> 
> As a matter of style, I prefer not to spread tags and tagged content
> over two lines.  I find this easier to read.

Ok, I tried to avoid them (as I saw that indeed the tags weren't
spread out, but I didn't know if that was the rule), but I guess this
one slipped out.


> > +  there's a limited total number of bits that you can spend; therefore it's
> 
> I think long forms (it is) are preferred over long forms (it's) in
> written English.

Grrr... How many times will you have to tell me that! I should be more careful.


> > +  On the other hand, it's worthless to raise CQ as higher than 0.30 as you'd
> 
> s/as//

So that would be the correct form: 
On the other hand, it's worthless to raise CQ higher than 0.30 as you'd


> > +  <screen>mplayer source_file.vob -aid 129 -dumpaudio -dumpfile sound.ac3</screen>
> > +  will dump into the file sound.ac3 the audio track number 129 from the file
> > +  source_file.vob (NB: DVD VOB files usually use a different audio numbering,
> > +  which means that the VOB audio track 128 is the 2nd audio track of the file).
> 
> If I am not mistaken the 2nd audio track is 129, not 128.

You're right.


> > +  Most people choose to compress audio with either MP3 or Ogg Vorbis audio
> > +  codecs.
> 
> Let's not further spread the false asssumption that Ogg and Vorbis are
> the same thing and/or inseparable.  Just say Vorbis when you mean the
> audio codec.

Ok.


> > +  First of all, you will have to convert the DVD sound into a WAV file that the
> 
> Please try to keep lines below 80 characters, or even better 60-70
> characters so that if small changes are made later on they show up
> nicely in the diffs.

Ok. I guess that's a rule I should follow in the manpage too.


> > +  Please note that MEncoder currently can't currently mux Ogg Vorbis files
> > +  into a video stream because it can only create AVI and MPEG files.
> 
> What are you trying to say here?  Either you have the distinction
> between containers and formats wrong or you are just writing it in a
> confusing fashion.  A video or audio stream can be muxed into a file,
> but not vice versa.

Yes, that's unclear. I think I understand quite well the distinction
between a container and a format.
What I'm trying to say here is that ".avi" as well as ".mpg" files
can't contain a Vorbis audio track.

Would it be clearer if I had written:
Please note that MEncoder currently can't currently mux Ogg Vorbis files
into a video stream because it only supports AVI and MPEG containers.


> Nice work.

Thanks! I'm glad that you liked it. Thank you for reviewing it.

There's one thing you did not comment on: the arithmetic expressions I
added don't have any a specific tag that could make them "shine out",
if I may say so.
For instance, the expression: ARc = (Wc x (ARa / PRdvd )) / Hc seems
to me "drowned" in the rest of the paragraph, when I think it would be
good if they would have their own style, just like LaTeX does.
I haven't found any existing tag for arithmetic expression on the XML
docs (maybe I did not dig deep enough), that's why I left it that way
for now. What do you think about it?

Other than that, I'm interested in any other nits you may have, given
that I have no experience with XML.


Regards,

Guillaume