Quantcast Using ffdshow/Libavcodec to Decode MPEG-4 - digitalFAQ.com Forums [Archives]
  #1  
03-01-2006, 04:30 PM
sparskter sparskter is offline
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Well, everyone says that using libavcodec to ENCODE @ MPEG-2 is not so good. So, what about using ffdshow to decode Videos[MPEG-2/MPEG-4/etc]/Audios[MP3/OGG/etc] to then encode @ any mpeg-2 encoder ?

I am asking this, because I had a serious problem with ffdshow. An avi of MEGAMAN X8 [http://www.speeddemosarchive.com] was not encoding until finish. I tried to uninstall ffdshow, using xvid instead and it worked

Bad luck ?
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03-01-2006, 05:57 PM
kwag kwag is offline
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Quote:
Originally Posted by sparskter
Well, everyone says that using libavcodec to ENCODE @ MPEG-2 is not so good. So, what about using ffdshow to decode Videos[MPEG-2/MPEG-4/etc]/Audios[MP3/OGG/etc] to then encode @ any mpeg-2 encoder ?
Every re-encode is another generation of quality loss.
Don't do that

-kwag
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03-01-2006, 07:20 PM
sparskter sparskter is offline
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Code:
LOADPLUGIN("D:\filters\fdecimate101\FDecimate.DLL")
AviSource("D:\[PS2]MegaManX8_100p_236_[PS2].avi")
RESAMPLEAUDIO(48000)
CONVERTAUDIOTO16BIT
FDECIMATE(23.976)
CONVERTTOYV12
Lanczos4Resize(304,208,16,7,290,218)
Addborders(24,16,24,16)
I am using this script above. And then I use it on HC encoder. I think ffdshow is only decoding my avi/mpeg-4 file.

Is this a re-encode ?
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03-01-2006, 08:33 PM
kwag kwag is offline
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You are "decoding" an AVI, to then "re-encode" (once again!) witn HC in this case.
So you are loosing quality by decoding and encoding again.

-kwag
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03-01-2006, 09:03 PM
sparskter sparskter is offline
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How should I process that .avs file ? The avi is original from http://speeddemosarchive.com

I simply opened it on Paranoia and then added some extra-commands. Nad then I open it (.avs) on HC encoder. There is other way ?
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  #6  
03-02-2006, 05:13 AM
Dialhot Dialhot is offline
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I think Karl read your first question in a wrong way.

Basically you are just asking "what about using FFDShow as a generic decoder to open any kind of source in avisynth". And the answer is in your first post : the experiment shows that this is not a good idea !

FFDShow does a lot a things, but never do them as good as the original codec. If possible, use the original (Xvid in your initial post).
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