[vdr] AW: Re: AW: Wish list for VDR 1.0

["Manfred Schmidt-Voigt" <1187-184@onlinehome.de>]

> -----Ursprungliche Nachricht-----
> Von: kls@cadsoft.de [mailto:kls@cadsoft.de]Im Auftrag von Klaus
> Schmidinger
> Gesendet: Samstag, 29. September 2001 11:10
> An: vdr@linuxtv.org
> Betreff: [vdr] Re: AW: Wish list for VDR 1.0
>
>
> Manfred Schmidt-Voigt wrote:
> >
> > Dear all + Klaus,
> >
> > the VDR project went on into the right direction and I am
> really surprised
> > how much time Klaus has invested to develop this product. And
> also all the
> > others, which provided parts of it, must be thanked for this. But, as
> > everywhere in life, the list of whishes never ends.
> >
> > So I have another (small?) wish:
> >
> > Sometime ago I got a patch from Klaus for the cutting process of the
> > recorded videos. This patch enabled me to set the cutmarks and when I
> > pressed the "2" button the new files contained excactly the
> lenght between
> > the cutmarks. Thats very usefull for archiving the videos
> further on to CDs
> > in any other compressed format (I like SVCD and the ablility to
> watch them
> > on a standalone DVD set)). The CDs than end up between two
> scenes and not in
> > between the "hottest action". This patch works very well for me
> but its a
> > little bit uncomfortable to include it again and again to the
> new releases.
> > And what happened if the great developers decide to change just
> that part of
> > code?
> >
> > So my wish (hurra, bald ist Weihnachten), please include it in
> the regular
> > distribution. Button "2" for the wellknown cut into near equal parts and
> > maybe button "3" for files up to the cutmarks.
> >
> > Cheers
> > Manfred
>
> Using '3' for this would be a bad choice, since I am reserving
> keys '1' and
> '3' for positioning on individual frames (including B- and
> P-frames) in case
> this will ever become possible.
>
> But what could be done is to make the editing process look at the marks
> and calculate whether the next chunk of data will still fit into
> the current
> file (limited by Setup.MaxVideoFileSize) and start a new file if
> it doesn't.
> This, however, could result in cases where one file would be pretty small
> if there is, e.g., a sequence of 500MB, 200MB, 500MB, and the
> MaxVideoFileSize
> is set to 650MB. While with the current solution this scenario
> would result
> in two files (650MB+550MB), the above method would result in three files
> (500MB+200MB+500MB). But if you want to split at your marked
> positions, this
> is what you get. Of course there would also have to be a Setup
> parameter to
> enable/disable this cutting method. I would assume that somebody
> who wants this
> alternate cutting method would _always_ want it, so wasting a valuable key
> would not be worth it.
>
> Klaus
You,re right, I would than prefere a fixed method by the setup menu because
I like to have all time the control of the cutting process. Your way of
collecting the pieces into one file is something what I don't like. I cut
allways into small pieces (only some scenes) because of several reasons:

- the loss of sync between video & audio, when all the diffenerent
demux/mux/compress/etc-steps occure until you have a real good peace of
SVCD, will increase with the size of the file. Your outputfiles are in sync
but there are always bad frames or loss of audioframes. So if you use mplex
(by the driverdevelopers) you have already the first shifts in your new
stream. I tried pvastrumento to mux the vdrs to an MPEG2 stream but the
result was even worse. For compression to SVCD I use tmpgenc (Yes, I know
that you don't use WINxx). But all these tools have sometimes difficulties
with large files. I know, this is another wish and the best would be if VDR
can provide directly files in SVCD format well synced and with optimal
quality, but...

- for optimal balance on the CDs after compression its always better to fill
the discs with small pieces

>
> > for completenes I will include the patch here again in case somebody
> > (Klaus?) has dropped it.
> >
> > >>>>
> > > If you want to have separate files for each part, you could
> try adding the
> > > following lines in dvbapi.c, cCuttingBuffer::Action():
> > >
> > >            // Check editing marks:
> > >
> > >            if (Mark && Index >= Mark->position) {
> > >               Mark = fromMarks.Next(Mark);
> > >               if (Mark) {
> > >                  Index = Mark->position;
> > >                  Mark = fromMarks.Next(Mark);
> > >                  CurrentFileNumber = 0; // triggers SetOffset before
> > reading next frame
> > >                  toMarks.Add(LastIFrame);
> > >                  toMarks.Add(toIndex->Last() + 1);
> > >                  toMarks.Save();
> > > +                toFile = toFileName->NextFile();
> > > +                if (toFile < 0)
> > > +                   break;
> > > +                FileSize = 0;
> > >                  }
> > >               else
> > >                  break; // final end mark reached
> > >               }
> > >            }
> > >
> > > Klaus

Thanx
Manfred

--
-------                   Manfred Schmidt-Voigt                  -------
-----                  Gunzweg 10, 22393 Hamburg                   -----
-----                                                              -----
-------          mailto:manfred.schmidt-voigt@bigfoot.de         -------