Apple Trailers: VLC and MEncoder transcode tests

[whome]

Test case:
webpage: http://www.apple.com/trailers/independe ... eforterra/
quicktime streaming url (sd): http://movies.apple.com/movies/independ ... _h.480.mov
internal video url: http://movies.apple.com/movies/independ ... a_h480.mov
quicktime streaming url (hd): http://movies.apple.com/movies/independ ... a_720p.mov
internal video url (hd): http://movies.apple.com/movies/independ ... _h720p.mov
internal video url (hd): http://movies.apple.com/movies/independ ... _h480p.mov
(see a small difference in file names)

All files are AVC1/MP4A files using ~2.40 display aspect ratio, storing pixel aspect is 1:1.
SD medium h.480: 320x136
HD 480p: 848x352

Apple uses fladh rtmp(?) streaming protocol, its a simple binary file where internal video link can be read.

I am using PS3MS dlna media server and its using VLC and MEncoder to transcode netstreams to mpeg2/mp3 files, safe bet to run videos on PS3 console. PS3MS does not support pass-through streaming if the original one was already ps3 compatible format, so everything goes to mpeg.

I get the MPEG1/2 does not support 2997/125 fps error message.
2997/125 = 23,976
24000/1001 = 23.97603...
30000/1001 = 29,9700299...

Run few standalone tests, I had to use fps=24 VLC option then was able to transcode. VLC can read a quicktime streaming url which is good.

Code: Select all

set source=http://movies.apple.com/movies/independent/battleforterra/battleforterra_h.480.mov set VLC=C:\Program Files\VideoLAN\VLC\vlc.exe "%VLC%" -I dummy %source% :sout=#transcode{vcodec=mp2v,vb=4096,fps=24,acodec=mp3,ab=128,channels=2}:duplicate{dst=std{access=file,mux=ts,dst="output.mpeg"}}

Here is Mencoder command line it supports 24000/1001 fps setting so its a perfect match. Mencoder can only use a direct internal video url.

Code: Select all

set source=http://movies.apple.com/movies/independent/battleforterra/battleforterra_h480.mov set MENCODER=C:\projects\PS3MediaServer\ps3mediaserver\win32\mencoder.exe %MENCODER% %source% -prefer-ipv4 -of lavf -ovc lavc -oac lavc -lavcopts vcodec=mpeg2video:vbitrate=4096:threads=2:acodec=libmp3lame:abitrate=128 -ofps 24000/1001 -o output.mpeg

Issues I have found
* VLC does not support a perfect match fps=24000/1001 option, but MEncoder can do it. Is this a big problem, am not sure if fps=24 gives sync problems in longer videos. Should I worry about this?
* VLC breaks the display aspect ratio and resolution, video is played distorted. MEncoder maintains the original resolution and aspect. This is a big problem, is there something to make VLC automatically maintain an aspect ratio?

[whome]

Here is another use-case.
http://www.vodcars.com/episode/3cp_20090123
http://libsyn.com/media/vodcars01/3cp_20090123.m4v

I must add fps=30 setting to fix "[00000448] avcodec encoder warning: MPEG1/2 does not support 2997/100 fps" error message. Is there any commandline to use a conditional (automatic if one is required) forced fps setting?

I am fighting for this on PS3MediaServer dlna netstreaming issue. It does not know what to use as all netstream URLs look identical before running any conversions. One way to hack is try converting first, read sysout log, is there FPS error messages, stop it, start again with fps=XX value. Ugly I know.

Code: Select all

set source="http://libsyn.com/media/vodcars01/3cp_20090123.m4v" c:\vlcetest> "C:\Program Files\VideoLAN\VLC\vlc.exe" -vvv -I dummy %source% :sout=#transcode{vco dec=mp2v,vb=4096,fps=30,acodec=mp3,ab=128,channels=2}:duplicate{dst=std{access=f ile,mux=ts,dst="output.mpeg"}}