mpeg2 players behaviour with dvb-s recorded streams

[MK <amk@befree.ch>]

Some MPEG decoder tests
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the test stream was a pva2mpeg-filtered stream captured from Arte.

here are the results for now:
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Dvdview 1.0.2
http://rachmaninoff.ti.uni-mannheim.de/dvdview/main.html
video: plays without visible degradation. good image. no resize available
audio: piped to mpg123, good quality
sync: gets out of sync, jumpy picture
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mpeg2dec 0.1.6 from the LiVid project (Aaron Holtzmann)
http://gusnet.cx/aaron/codecs/mpeg2dec.php
bombs out with a 
(vlc) invalid huffman code 0x0 in vlc_get_block_coeff()

---------------
nist 0.6 (binary and code available) (related to the precedent)
http://home.germany.net/100-5083/index.htm
bombs out with a 
failure in programm pack
Bitrate: Floating point exception    
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mtv 1.1.4 (commercial software, binary only)
http://www.mpegtv.com
launches four mtvp processes for playback and 
immediately after dies a silent death.

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under windoze, the same converted pva gave the following results:

transcoders:
* rempeg2 : crashes immediately
* flaskmpeg : no problem. 

players :
* dvd station / hollywood+ (hardware decoder) : perfect, no errors.
* ligos lsx decoder (with wmp): correct image, but washed-out colors and
excessively blurry.
* ATI DVD player (cinemaster engine): very dark, way too much contrast,
corrupted images (jumps, tears, wrong macroblocks...). Un-usable.
* Cyberlink PowerDVD: very dark and contrasted, as above, but no image
corruption. usable. 
Of all the players PowerDVD was the only one able to attempt to play the
unmodified pva, but with a corrupted image and a crash.
* Windvd 2000 2.1: does not run at all, just plays (correctly) the audio
stream.

none of the above showed audio-video sync problems.

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Conclusion: not all the mpeg2 decoders have the same tolerance to errors. 
There is a possibility of dealing even with a slightly faulty stream.

For Linux, of all the free decoders, dvdplay certainly looks the more
promising. The image was certainly on a par with the best software decoders
under windoze. Needs image resizing, audio sync and smooth play. 
For the windoze players, the sharper the image the more sensitive to errors
(cinemaster vs. ligos decoder). no surprise there (excepted for powerdvd).


Other miscellaneous stuff:
------------------
fame (mpeg2 I-frame-only encoder and rtp) GPL
does not compile under mdk7.1
wrong nasm detection routine in the config script
------------------
Mpeg movie (from heroinevirtual, same author as broadcast2000)
massively hard-coded header locations throughout the code,
does not compile under mdk7.1 (but the mux/demux routines do and look
useful).
-----------------
Kderadio
radio app. does not compile under mdk7.1
-----------------
Gstreamer "a framework for streaming media in GNOME"
does not compile under mdk 7.1
----------------

more on the transcoders soon.

Cheers,

MK