Belated reply to Dark Shikari

[papilio]

Hi all,

First off, I'd really like to know whether anyone has any suggestions as to how I might fairly innocuously reduce a video clip's file size *before* compression. I'm currently using YV12, which certainly helps in reducing the size, (but seems to make the color kind of strange,) but is there a better color format which I might be using? More to the point, other ideas of any sort?

Secondly, I'm having exceedingly bad luck with MC's H.264 encoder (full res with my Dell 24-inch WS, 1920x1200) -- and lowering the Fraps/GE screen res simply loses too much detail -- Plus changing to 16-bit color is unacceptable, and probably wouldn't make a difference anyway, as it doesn't seem to affect Fraps. With any setting which produces the great MC image quality, the playback jerks, consistently and constantly, say 3 times a second. I'm currently using WMV9 advanced at 98 quality High-quality VBR (surprising how much that reduces the file size, while barely lowering image quality), and which is certainly the best encoder I've found so far, though everyone says it's no comparison with the H.264 -- and I could live with the WMV9 encoder, but the output image from H.264 seems virtually lossless, and I'd love to get it to work! I'm using a Duo core Dell (2x1.86), and the CPU load seems not to be the problem -- it's generally around 50%. And it stays at the same level no matter whether I'm at 720P or 1080P, nor at 25,30 or 50 or 60 fps (though file-size grows of course). How odd! Also a 7600GT nVidia card, if that's relevant. And 3 Gigs RAM.

With MC, it's most likely a problem of inexperience/mere lack of knowledge in finding the appropriate settings. I'm trying to encode clips of Google Earth Fraps screen captures, though several posts have claimed that GE is difficult to work with, but I process and reduce the file size considerably after using various filters (I use VD almost exclusively), so I don't understand why that should be the problem. I'm also using Core AVC Pro to decode, which helps quite significantly, but of course the problem remains. Ffdshow seems to cause all sorts of problms, so it's not installed. And, again, the problem occurs to precisely the same extent regardless of whether I'm at 1080P or 720P. Also using Zoom player, which is clearly less of a resource hog than WMP11. I'm hoping to find a way to produce a 720P video which I can share with people with slower machines, having them install the required decoders and such, obviously.

Is there perhaps another H.264 program (non-source -- I have no clue what to do with that) with which I'd have better luck? I'm certainly not overjoyed that I spent all that project money on MC!

Please, someone offer some help (maybe the proper MC settings, though other suggestions would be preferred). The success of this project is rather important to me right now.

Thanks!

-- Michael :rolleyes:

[Dark Shikari]

You really didn't need to buy MainConcept--x264 is free and quite easy to use, especially with a GUI like MeGUI or Handbrake.

But on topic, 50% of the CPU on a Hyperthreading or Dual-Core system means that you've maxed out one of the cores... meaning you have a singlethreaded decoder, and your CPU is too slow to play it at full speed.

If you insist on high resolutions but want people with slower machines to be able to play the video, WMV9 and Xvid are probably your only real choices.

To reduce a video's size before compression just use a lossless video codec. In order of effectiveness for the more common ones:

HuffYUV (Fastest)
Lagarith
H.264 Lossless (slower compression than others on the list but relatively fast decompression)
FFV1 (Slowest)

[zambelli]

I can't answer the MC question, but I can give you some advice on the WMV9 encoding. I've been playing with quality VBR encoding in WMV9 lately and there are a few things you can do to give the video some more flexibility, possibly reducing the filesize even further at no perceptible quality loss.

Using WMV9 PowerToy or WMCmd.vbs (see my sig), enable:
* Perceptual Option = Adaptive Dead Zone
* Dquant Option = I, P & B frames
* Dquant Strength = Very Smooth (QP=1)
* B-Frames = 1
* B Delta QP = 1
* Lookahead = 16

You will need WM Format 11 installed for this to work, and Advanced Profile is necessary for the Dquant option (though Main Profile will do just fine, but without Dquant).

At Q98 the QP used for all frames is 1.5. Using B-frames and fixed B Delta QP additionally pushes out B frames to QP2.5, which means practically every other frame will get compressed slightly more. Dquant offsets this balance by occasionally using QP=1 on smooth areas. Finally, Adaptive Dead Zone varies the quantization level based on texture/smooth region ratios in a picture.

Try it and see what kind of results you get, both quality wise and size wise.

[papilio]

Thanks zambelli,

Your pieces of advice are some of the many things I'm totally ignorant about, (most of this stuff is pretty new to me) so I'll certainly give your suggestions my best try!

Thanks again,
-- Michael

[papilio]

zambelli,

Checked out the FAQ you mentioned -- where is MFPKEY_COMPRESSIONOPTIMIZATIONTYPE -- apparently not in the registry.

Thanks

[zambelli]

zambelli,
Checked out the FAQ you mentioned -- where is MFPKEY_COMPRESSIONOPTIMIZATIONTYPE -- apparently not in the registry.
That's "Compression Optimization Type" in the registry. http://www.microsoft.com/windows/windowsmedia/howto/articles/codecadvancedsettings.aspx has the full list of registry keys (the documentation will be updated in a few days).

The WMV9 PowerToy will let you set all the settings from a GUI interface.

[papilio]

Hi Dark, thanks for your reply.

I just realized that for some reason -- mistake of mine obviously -- my response to your reply to "File-size reduction suggestions and MC H.264 woes" didn't get posted. I'll try to remember what comments/questions I had Re: your reply ---

Discouraging to hear about the inadequacies of my Dell Dual Core, but thanks for setting me straight on that. The Dell has 2 1.86 processors. My previous machine was an HP Pavilion 2 GHz, and the Dell has up to this point/application been *at least* 4 times faster than the HP. I might be willing to sell the Dell in favor of a straight processor, (I also do quite a bit of Rhino/Flamingo rendering, which takes 2-4 hrs on the Dell, so a speed increase for that would be great too -- my HP would generally take 20 hrs or so.)

But my web searches yesterday give me the impression that the PC industry has hit a speed wall of some sort -- my guess is a difficulty in reducing the size of the processor circuitry any further. My 2 GHz HP was probably 5 years old or more, and the processors I can find these days are 3-4 GHz at best. (I've always had a rule to wait to get a new computer until the new one is at least 5 times faster than what I had, and in the past that sort of improvement seemed to take no time at all!) Might you have any suggestions or recommendations (within a reasonable price range)? At this point I'd be a hard sell regarding Macs, though one's mind and beliefs can always be changed!

I already have meGUI installed, though I haven't played with it enough to really know how to use it yet -- but I'll certainly give x264 a try (already have it too). For some reason I had gotten the impression that it was only a decoder.?

Could you enlighten me on the *singlethreaded decoder* issue, and possibly offer some workable replacements?

And finally, (and an important question) -- you suggested reducing file size by first using a lossless codec. I had always thought -- very possibly in error -- that VD uncompressed the file it was given and then re-compressed with one of the (playable) lossy codecs installed on the machine. I already have, of course, HuffYUV, and it's wonderful to see the lossless (though unplayable) output. Is there a workaround, or another program which can take a lossless compressed video and re-compress *that*?

I just tried a secondary compression -- WMV9 -- on a HuffYUV video, and the result in this case was unsucessful, just as I had expected. Did I do something wrong?

Thanks again for your response,
--Michael

[markrb]

If I may. Pure Ghz numbers these days are not what they used to be in terms of actual CPU power.
In the last 5 years both AMD and Intel have complete new architectures that do more, much more, with less.

Todays overall power leader(x86 desktop) is the Intel Core 2 Duo line. The newest versions were just released last week and are the 6x50 line with a 1333 front side bus.
Take a look at this http://channel.tomshardware.com/2007/08/25/cpu_charts_channel/ and see if it helps out any.

Mark

[papilio]

Hi Marc, thanks for the reply.

Very important stuff to know -- the link was especially illuminating!

Cheers,
-- Michael