[MEncoder-users] Trouble transcoding 1080i "video" to NTSC DVD -- SOLVED!

[Dominik 'Rathann' Mierzejewski]

On Monday, 13 March 2006 at 20:05, Walter Belhaven wrote:
> --- Walter Belhaven <wbelhaven at yahoo.com> wrote:
> > 
> > I'm having trouble transcoding 1080i HD "video" (interlaced) content
> > from my Tivo HR10-250 to "standard" NTSC DVD.  The video source is a
> > live hockey game.  [...snip...]
> 
> Hi,
> 
> After a bit of stubborn persistence, I've finally gotten this to work.
> The video quality is absolutely stunning, so a huge "thank you" to the
> folks implementing, testing, and supporting mencoder, ffmpeg, etc.

Great! And thanks for sharing your solution with us.

[...]
> Here's the mencoder command line I settled upon for each file (and
> repeat with vpass=2 for a 2-pass VBR encode).  Original files were
> 1080i at 1280x1088 with a 384kbps AC3 audio sound track:
> 
> mencoder \                 # Righteous open-source transcoder. :)
>  -oac copy \               # Leave Audio "as is" (AC3 DD5.1 384kbps)
>  -ovc lavc \               # Use lavc to transcode the video
>  -of mpeg \                # Output "container" is MPG
>  -mpegopts format=dvd \    # - specifically, DVD-compliant MPG (VOB)
>  -vf \                     # Filters:
>     [phase=t,] \           # [Only when field order needs reversing]
>      crop=1264:1072, \     # Crop to multiples of 16 (see man!)
>      scale=720:480:1, \    # INTERLACE-aware scaling to DVD res.
>      harddup \             # See man: helps keep A/V sync
>  -lavcopts \               # Codec options:
>      vcodec=mpeg2video: \  # Output video is mpg2
>      vrc_buf_size=1835: \  # DVD Standard sez so
>      vrc_maxrate=9696: \   # Max = 10800 (DVD max) - 384 (audio)
>      vbitrate=5731: \      # Makes the whole thing fit on one DVD-R
>      keyint=18: \          # DVD Standard sez so (NTSC)
>      aspect=16/9: \        # Cuz it is. :)
>      ildct: \              # INTERLACE-aware DCT
>      ilme: \               # INTERLACE-aware ME
>      top=0: \              # Output Top field first
>      mbd=2: \              # /  Some "high quality" options
>      trell: \              # \  (off on first pass)
>      vpass=1 \             # [Change this to vpass=2] on 2nd pass

Instead of not using specific options in pass1, I suggest using :turbo, which
can be used during both passes, but turns off the cpu-intensive options in pass1.
Additionally, I think you should try mpeg_quant:cbp:mv0 and experiment with
preme=2, *cmp=2, last_pred=2 and various *dia sizes. Other than that, the command
looks fine.

>   -ofps 30000/1001 \       # NTSC standard frame rate (interlaced)
>   -o output.mpg \          # Output file
>   input.mpg                # Input file
> 
> Anyway, hope this helps other folks struggling with the same thing. 

So do I. Perhaps we can include that in the encoding guide. HDTV content seems
to be all the rage these days. :)

Regards,
R.

-- 
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