[mythtvnz] Advice for encoding ...

[Nick Rout]

On Wed, May 27, 2009 at 2:27 PM, Nick Rout <nick.rout at gmail.com> wrote:
> On Wed, May 27, 2009 at 2:21 PM, Steve V <olivuts at yahoo.com> wrote:
>>
>> I use this for the interlaced channels i.e. TV3,4,5,6,7,8 20 etc
>>
>> Handbrakecli -i "freeview.mpg" -t 1 -c 1 -o "freeview.avi" -f avi --crop
>> 0:0:0:0 --deinterlace="slower" --decomb  -p  --detelecine -e xvid -q 1 -r 25
>> -a 1 -E lame -B 320 -R 48 -6 dpl1 -D 2.5 -v
>>
>> And this on the progressive TV1 & 2  (720p channels)
>> Handbrakecli -i "freeview.mpg" -t 1 -c 1 -o "freeview.avi" -f avi --crop
>> 0:0:0:0 -e xvid -q 1 -r 25 -a 1 -E lame -B 320 -R 48 -6 dpl1 -D 2.5 -v
>>
>> This gives you a rather big Lossless XVID .. (the -q 1 will give you 100% of
>> original)
>> Then edit out the start/end/adverts from the xvid using Virtualdub, avidemux
>> or whatever your favorite video editor is and encode out to your the final
>> format.
>> I still encode everything out to Xvid using data rates of @1800k for SD , or
>> between 3000-3500k for 720p, which gives very close to original h.264
>> And prefer using virtualdub on windows, as the encoded as the status window
>> for the second pass, gives the quantizer display for how well the codec is
>> doing on encoding into the specific bitrate.
>>
>> Shame Handbrake has no editing feature, nor any feedback during the encode.
>> Great tool for deinterlacing & converting h.264 into something more useful
>> than standard tools can use thou.. Note if you miss off the framerate (-r
>> 25)
>> handbrake encodes TV1 &2 & 50fps... even thou it's progressive 25fps.
>> Also one of the sound options in handbrake completely kills playback on
>> mplayer on my 9.04 box..
>> I forget which option, but  haven't encoded anything that I've kept the
>> surround sound on..
>>
>> Regards
>> Geoff
>>
>> Thanks for the info - looks like I will be looking into some of these tools
>> - HandBrake and Virtualdub .
>>
>> I take it there is no way to transcode via myth first and honor the cut
>> list. I am finding that the Myth Commflag is about 80% accurate for cutting
>> out adverts - the cutlist only needs a little adjustment after commflag - so
>> it saves heaps of time compared to editing in another package and having to
>> find the adverts manually.
>
>
> Two problems here that I perceive:
>
> 1. Most myth devs are in the US and don't care about anything other
> than mpeg2 as thats what they are fed. Fair enough in some ways,
> especially as they don't have the streams to play with.
>
> 2. Speed of mythtv development means myth's internal ffmpeg code lags
> the ffmpeg dev's code by quite some months.
>

A possible approach?
================

1. Get your cut points right by commflag plus editing to get them
100%. The cutpoints are in the database.

2. Convert the cutpoints to the format used by avidemux, in fact they
may even be the same, "frames from start of file (I think) - this I
need to check.

3. Use avidemux on the commandline to process the file, cutting out
the cutlist. avidemux is quite programmable using a javascript/ecma.

http://www.avidemux.org/admWiki/index.php?title=Scripting