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  1. Hi all,

    I'm having trouble getting anything to encode at any reasonable speed with GK or XMPEG using the Xvid codec 1.0b3.

    I'm working with DVD compliant MPEG2 files recorded from an WinTV PVR card (8.2mbps vbr) with Mpeg2 audio. These files get about 5-7 frames per second encoding rates on my machine with deinterlacing, and 3-4 frames per second without. Does that seem normal?

    I'm doing 2 pass encoding and the frame rates I'm reporting are an average between the two passes (meaning that this process is about 15-20x realtime).

    The settings I use for Xvid with the AS @ L5 profile are:

    q-pel
    VHQ 1 (mode decision)
    MPEG Quantization with custom matrix (HVS Best picture)
    interlacing (if no deinterlacing is applied)
    trellis quantization
    chroma motion
    Max 2 conseq. b-frames
    Target Bitrate: 3200kbps

    I encode at full D1 resolution (I've also tried 640x480, but this doesn't make much difference).

    My Machine is a P4 2.4 800mhz FSB with HT
    512mb ECC Memory
    160gb 7,200 rpm WD HD (IDE/UDMA)

    My software versions are: GK 0.28.72, Xvid 1.0b3 (binaries from Koepi), and XMPEG 5.03

    Thanks in advance!
    wade
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  2. Member teegee420's Avatar
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    That doesn't sound right at all. Your system is faster than mine and I get speeds of 14-24fps. I use Virtualdub MPEG2, but that shouldn't matter because the actual compressor is the same.
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  3. Yeah, that's what I figured, but I can't see anything wrong with my configuration that's obvious. BTW, I think GK uses VirtualDubMod to do the actual MPG 2 AVI conversion.

    I tried a similar setup last night on my P4 2.6 but I got similar results, speed-wise.

    Are you encoding at full 720x480 resolution?

    wade
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  4. Nothing wrong with your set up - mine is very similar. It's all those damned setting in the AS @ L5 profile that are making it slow! I've just tried using them and got the same snail like results results. I then went back to my 'normal' setting of 'Unrestricted' (i.e no profile) and achieved my normal speed of 21-25 fps. To be honest I didn't notice any difference in the quality of the output either - a very subjective view I know!

    One thing I did notice, if you want to try this, you must edit the 'unrestricted' profile and get rid of all the settings you had in the L5 profile as they seem to stick!

    One other thing. The clip I used to try this was a 8mbs VBR mpg2 with very high motion and i do set the Advanced Options tab to Motion Search Precision to 6-Ultra High

    Also I don't use GK or XMPEG. I just capture and frameserve to normal Vdub with AviSynth (that way I can use any filters outside Vdub and still use fast recompress)
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  5. Cool,

    Can you tell me what your normal setup is? I'd like to try it and see if I get similar speeds. I noticed that my setup is close to what Doom9 uses, but I can't, for the life of me, figure out how they get an average of ~38 fps with them.

    wade
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  6. Never looked at anybody else's settings - I just played around until the results looked ok to me.

    Anyway it's pretty much as I've said previously. If I'm only doing 1 pass then I find a bitrate of 1500 more than adequate, if I'm doing 2 pass then I just put in the file size I want on the 2nd pass. Set the Advanced Options tab to 6 High-Ultra high but apart from that I leave everything else as default. I rarely(if ever!) deinterlace and don't do any cropping or resizing (my captures are 720*576 but slightly cropped and as I'm only playing back on PC or TV out it doesn't matter what the framesize is). I also convert to 128k mp3 for audio, which again I find quite adequate. Also I use Fast Recompress because I'm not using any Vdub filters

    I dunno where Doom9 get there 38fps from though! Could be the incoming framesize is quite small (352*288) or something which might speed it up I suppose. Not sure on that one though.
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  7. I think the doom9 numbers must come from resizing. They encode at 640x352 and lower some of their benchmarks.

    If I turn everything off, that is all of the extra quality features, and b-frames, I can get closer to 32-34 fps, but that makes the quality noticeably worse.

    Too bad Nero Digital doesn't convert raw Mpeg2 files, then I could do the whole conversion in about 2x realtime.

    wade
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  8. Member teegee420's Avatar
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    Originally Posted by swadey
    Too bad Nero Digital doesn't convert raw Mpeg2 files, then I could do the whole conversion in about 2x realtime.

    wade
    No kidding. What a huge feature that would be. Makes me wonder why it wasn't included.
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  9. On a related Nero Digital note, I have several 9-10gig mpeg2 files that I want to get into a VOB/DVD stucture on my harddrive so that I can use Nero Digital. Any ideas about how to do this? Or even just to convert the mpeg2 into a vob?

    wade
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  10. Member teegee420's Avatar
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    Let me preface by saying that I have a habit of doing things the hard way sometimes so take my advice with a grain of salt. I would de-multiplex your mpegs and select your files to create a DVD in DVDlab or TMPGEnc DVD Author. Then take the VIDEO_TS and AUDIO_TS folders and create an ISO using UltraISO. Then I would mount the image to a virtual drive and select it when using Recode 2 for Nero Digital.

    Logic tells me that there has to be an easier way, but given by affinity for tedious undertakings it's the best I could come up with. :P
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  11. swadey,

    Maybe the best bet is a some sort of compromise between basic settings and the full L5 profile setting? Dunno really

    On the other subject I'm displaying my ignorance here but what is Nero Digital?
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  12. Member teegee420's Avatar
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    Nero Digital is the proprietary mpeg-4 compression of DVD's using Nero Recode 2. It uses an mp4 container and encoding time is fantastic(upwards of 60fps). Video quality is decent. I'd characterize it as being about as good as Divx, but not quite as good as Xvid.
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  13. Thanks teegee420,

    So basically you'd be paying for a piece of software that's not as good ,in terms of quality, as the free software you already have!

    I bet that's never happened before!!
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  14. If quality is all your concerned about, I guess you might stick with XVID, but imho Nero Digital, if it were to be packaged as a *real* codec would be preferable given it's stability, speed (almost 2x faster if you're using the high quality settings) and better audio quality (AAC encoding).

    I can't really tell the difference between the two codecs unless I freeze frames. Then I start to see more softness or blurring in Nero. This may be because of some pre-filtering that they are doing, or it could be because of the encoder - don't know. It would be nice to have a fully controllable version, independent of Nero Recode that we could really do some testing with.

    wade
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