Blocky Video

[jagarus]

Lately, my video encodings are coming out blocky with xvid and encoding with virtualdub. This hasn't happened before. What is wrong?

[josephu]

try pressing the reset defaults button in vdubs dialog when configuring xvid, and then starting from scratch...

[jagarus]

This is how the video is encoding. I have ffdshow installed.

[Enchanter]

Have you made sure that post-processing is enabled under FFDShow (most importantly the Deblocking components)? Make sure that you are not using too low a bitrate for your videos as this will undoubtedly lead to videos riddled with compression artifacts.

Regards.

[jagarus]

I tried encoding a 22:57 episode with virtualdub mod and xvid. FFDSHOW post processing settings are set. The video came out to 41.7mb after 2 passes with 992kb/s bitrate, 64kb/s audio and 512/384 video. The video ended up to the same quality as the picture above. I have been encoding for about a couple months now everyday but this has never happened.

Something wrong with my settings?

[Enchanter]

"22: 57 long, 992kbps video bitrate and 64kbps audio bitrate."

They WON'T add up to 41.7MB. 175MB should be more like it.

Something is wrong with your encoding setup and the diminutive filesize explains why you have been getting such low quality. Try resetting the XviD compressor settings (Load Defaults...) as previously suggested by josephu.

Cheers.

[jagarus]

I used the temporal smoother filter once and after that it started getting the blocky video.

[zx50]

Smoother filter, is this that feature on the last page because i never use that, i always have the on 0. The higher you set that the more quality/detail you can say goodbye to, if you want the sharpest picture that you can get then i would suggest that you remove the smoother filter altogether (ie 0), if thats the one your using of course, on the last page, if not well!!

[Enchanter]

zx50,

What are you going about? The use of a smoother will only increase the compressibility of the video and will therefore reduce the likelihood of macroblocks. Your suggestion to remove the smoother filter altogether is irrelevant in this case.

Regards.

[zx50]

What actually is the smoother for, because whenever i've set it to half the length of the film because the tip tells you that the number of frames worth of buffer between the adjusted encoding quality and the current quality, so like i said when i set the smoother to half the length of the film (might have been a bit too much) there was no detail hardly at all in fact just like a DivX actually, so well there you go...

P.S could you answer this for me, what the hell does max overflow and max degration mean. When it says how much of the overflow the codec can eat into i don't know whether it means how much % of the bits it can use when it needs to or how much of the bits it can take away for another scene, thanks

[Enchanter]

Care to tell me what sort of smoother filter (and one that allows for partial operation half-way through the movie, as you described) this is? There is no smoother filter built into the XViD codec, so obviously it is an external filter you are using and which you failed to tell us what in the beginning.

The question you asked me falls under the category of Alternative Curve (which I never bother with using, for various reasons). Hence I cannot be sure of the answer, but from what I have deduced, it is something similar to the Payback algorithm under the Two Pass category, where the codec takes away bits from low-motion scenes (which don't require much bits) and gives them to high-action scenes (which require much more bits). Obviously these values determine how much is to be taken from/given to specific set of frames. These default values were suggested by the expert people behind the XviD codec and for good reasons too, and I personally wouldn't bother experimenting with them (especially when I saw no visible improvements when I tried them out some time ago).

Cheers.

[zx50]

I don't know whether it is a smoothing FILTER, but i think you'll find that there is a smoother on the last page of the nic XviD codec and others. What it is for i don't 100% know, i thought it was for as it says giving the least amount of quality but but turned out it just totally smoothed the picture like an DivX film which i thought aagghh, so ever since then i just took it off and the picture has been nice and sharp ever since!!

P.S last page of the XviD codec the latest version, i use nic's!!

[Enchanter]

I am using Koepi's build for now. I'm not sure what features Nic's builds have over Koepi's, but since you find Nic's built-in smoother (if that really is a smoother) terrible, simply refrain from using it and opt for a better smoother filter. As far as I care, image-altering features, such as smoothers and deinterlacers, built-into codecs have given anything but outstanding quality.

[zx50]

Hmmnn i've used koepi's in the past and find that it does'nt keep as much detail as nic's (whether that's just me or what i don't know) in fact i've tried them all umaniacs the whole three, and the worst codec out of them is umaniacs without a doubt, i would'nt p*** on their codec, koepi's comes in second and number one is nic's but that's just my opinion!!

P.S i find that koepi's is too fast, i don't really like fast codecs anyway, i've been told in the past that fast does'nt nessicerarily (hope i spelt that right) mean worse quality, but well i still like a slow codec say about 7 - 8 hours in other words overnight!!

[Enchanter]

"i find that koepi's is too fast, i don't really like fast codecs anyway, i've been told in the past that fast does'nt nessicerarily (hope i spelt that right) mean worse quality, but well i still like a slow codec say about 7 - 8 hours in other words overnight!!"

The first time I see someone who likes things slower...

I certainly found little, if any, difference between Koepi's and Nic's builds and what perceived difference in after-decoding quality is usually associated with the decoder (Koepi's uses a plain vanilla decoder whereas Nic's uses its own more powerful, but relatively buggy, decoder). Using FFDShow as the decoder sees everything on the same quality level.

Taking into account that both builds give similar quality (in my case anyway), I would certainly take the faster codec any time of the day. My thought would be on Koepi's build being more efficient than Nic's.

Cheers.