How does XviD compare?

[Seraphic-]

Hi,

Basically, i'm still not sure what codec to use for my videos. :confused:

I've been using Real Video/Audio 10 for awhile now, but i'm not sure if I should switch to XviD or DivX. I mean, I guess RealVideo is somewhat out-of-date now, but is its encoding process still on par with the newer codecs? (I should add that it seems Real Video 11 is in development)

Could those who are experienced with Xvid and DivX share how these codecs compare to Real Video/Audio 10 with a target bit-rate of 2000 or 2500 and with 128kbps AAC for audio?

Thanks

[Prettz]

You can try looking here: http://www.doom9.org/codec-comparisons.htm

Xvid would be your best bet, since it's a lot more mature and easier to learn than the H.264 codecs (and fewer encoder options that you have to play around with).

Don't be afraid of using some of the custom quantization matrices floating around this board, either.

edit: 2000kbps will give you almost exactly 3 CDs. You'll get straight up DVD quality with Xvid on most all DVD sources with that kind of bitrate.

[Seraphic-]

Hi,

Please take a look at these:

The first image is the raw avi and the second is rmvb at 2,500. And even at 2,500, with RealVideo 10, there is a good amount of color loss and softening of detail.

(Note: These are for videos that will be download over the internet. Not really for VCD's or DVD's)

http://www.seraphicgate.com/raw.jpghttp://www.seraphicgate.com/rmvb.jpg

[Prettz]

3D rendered graphics? Man, you chose the absolute worst possible video codec for that purpose with Real Video. RV10 is MADE with the intent of softening the picture and blurring out detail; that's what it's supposed to do.


I don't know what would work best for that kind of source material, a very sharp custom quant matrix or a somewhat softening one. A very sharp matrix will leave you with lots of mosquito noise artifacts if you don't use a high enough bitrate. Someone else on the Xvid board can probably give you better advice about encoding 3D graphics.

[Seraphic-]

3D rendered graphics? Man, you chose the absolute worst possible video codec for that purpose with Real Video. RV10 is MADE with the intent of softening the picture and blurring out detail; that's what it's supposed to do.

Oh? I thought it was like any other codec at high bitrates. I.E - It would try to keep as much detail as it could.

I don't know what would work best for that kind of source material, a very sharp custom quant matrix or a somewhat softening one. A very sharp matrix will leave you with lots of mosquito noise artifacts if you don't use a high enough bitrate. Someone else on the Xvid board can probably give you better advice about encoding 3D graphics.

Well, i'm not really sure what XviD settings to use as most of the stuff i'm finding is REALLY old. However, when using the default XviD settings found in VirtualDub, it seems like 1,500 XviD looked better then 2,500 RM10.

What encoding tool do you use for XviD? I tried using "RealAnime" but it didn't seem to work right. I'm looking for something with AAC and allows for saving XviD in another video container.

[Prettz]

Oh? I thought it was like any other codec at high bitrates. I.E - It would try to keep as much detail as it could.



Well, i'm not really sure what XviD settings to use, as most of the stuff i'm finding is REALLY old. However, when using the default XviD settings found in VirtualDub, it seemed like 1,500 XviD looked better then 2,500 RM10.

What encoding tool do you use for XviD? I tried using "RealAnime" but it didn't seem to work right.
I max out all the settings for quality, encoding time be damned.

Since you're looking for quality I wouldn't use more than 1 consecutive b-frame, and you can even turn off b-frames if you don't mind using a whole lot more bitrate. Because b-frames must be quantized higher than the p-frames, and for your source material, the visual quality of a quant 3 b-frame surrounded by quant 2 p-frames might still not be good enough for you. That would be up to you, though.
Trellis quant: on
Adaptive quant: off
VHQ-4 and VHQ for b-frames on
QPel: on
GMC: off (it's generally useless)
Chroma motion estimation: on
Leave the other settings at their defaults.

As for what custom quant matrix to use, I couldn't really help you. If you have the time you can make a few encodes, varying only the matrix between each, and compare them yourself. There's several matrices made for extreme, even ludicrous, detail preservation (like the "SixOfNine" matrix) at extreme, even ludicrous, bitrates.

If you don't want to test encodes with different custom matrices yourself, the only ones that I've personally tested and could recommend are "hvs-better" or "hvs-best". They would definitely be better than the standard MPEG matrix for what you're doing.

[Seraphic-]

Thanks, i'll give those a try. Now do you use VirtualDub or another encoding tool? I don't think VirtualDub can have an AAC or save in another video container. (I could be wrong about both. But for audio, I can only seem to get MP3 to work. If I pick MPEG-Layer3 it takes me back to MP3)

And in tearms of size vs quality. I was looking to get around 15MB a minute at 636x444 video resolution. I do want quality, but they can't be too big. 20MB per minute would be too much.

[Prettz]

I just started using MeGUI (yesterday, even) and I'm liking it. It's even a tad bit easier to use than VirtualDub. The Xvid config screen on MeGUI is for some reason very different from Xvid's VfW config screen that you get with VirtualDub, but there's nothing missing at least (actually I haven't check that yet).

Assuming I did the math right, 15MB per minute is 2Mbps. Is that what you actually meant? That's gigantic, especially for that tiny resolution.

And for the resolution, unless there's some reason why you absolutely can't, you're going to want to make the encoded resolution have a width and height that are both multiples of 16 (look at one of the sticky threads with MPEG-4 info in it to find out why, if you don't know). You could even upsize your video to 640x448 (since you seem to have so much bitrate to use) and then configure Xvid to make the display aspect ratio the same as the original video.

[Seraphic-]

The reason I want to use a lot of bitrate is to insure quality. If I can use less, but still insure good quality, I will use less. Also, 15MB per minute is not really "gigantic". I mean, I could try to go even less, say 10MB per minute, but I wanted to go a little extra to insure good quality. Are you trying to say that XviD would do well even at around 5MB per minute?

I capture at 720x480, but during my testing I must crop down to 636x444 in order to remove all black bars. I could crop in multiples of 16, however, it would leave less video for the final cut.

[foxyshadis]

Non-mod16 hardly ever has a severe quality drop, often not even a minor one. See where the game footage falls in the presets thread and give it a shot, you'll probably be pleasantly surprised at how well it comes out. Then you can post sample videos and a screenshot comparison to answer your own question. ;)

[Manao]

Hum, since your videos don't have any noise / any grain at all, I can't see how XviD could be better than x264. I would strongly advise using it, the resulting video will be sharper.

[Prettz]

Hum, since your videos don't have any noise / any grain at all, I can't see how XviD could be better than x264. I would strongly advise using it, the resulting video will be sharper.
I figured Xvid would be easier to use, though, and harder to make a mistake with. I got the impression he was very concerned about keeping a sharp, accurate picture with no smoothing, so you'd have to be careful with setting your in-loop deblocking right in x264. Or is there a factor here that I'm missing?

[Seraphic-]

foxyshadis, what is Non-mod16?

I just installed MeGUI for x264, however is it normal for it to fail on the second update? It says something like server not not found? Also, do I need to import all these profiles?

Anyway, this really has a lot of options. I guess i'll have to try and find a guide as on most of this stuff i'm not sure what to use.

[check]

Read the wiki in my sig for basic meGUI guides - if you can follow the DVD ripping guide doing transcoding is almost exactly the same.
As for failing on the second update, what do you mean? One problem at the moment is if it downloads new presets in the updater it will pop up the preset import window behind other windows, so you won't notice it's appeared.

[Manao]

mod16 means you can divide the width & the height by 16. Since most codecs ( XviD & x264 in particular ) use as a base unit a 16x16 macroblock to compress the video, the codec will (roughly) encode a 639x479 ( non mod16 ) and a 640x480 ( mod16 ) video with the same bitrate & quality. So it's better to choose 640x480, since the resolution is bigger.

Of course, you're first concern is really to crop out the black bars ( because 639x479 without black bars is _a lot_ better than 640x480 with a single line black bar )

[Seraphic-]

Read the wiki in my sig for basic meGUI guides - if you can follow the DVD ripping guide doing transcoding is almost exactly the same.
As for failing on the second update, what do you mean? One problem at the moment is if it downloads new presets in the updater it will pop up the preset import window behind other windows, so you won't notice it's appeared.

Thanks, i'll check that out.

And it looks to fail on the "neroaacenc" update. "Can't find server"

[check]

ahh, neroaacenc is not on the update server any more (legal issues). You'll have to download it yourself. Google "nero digital" and get it direct & free from nero.

[Seraphic-]

mod16 means you can divide the width & the height by 16. Since most codecs ( XviD & x264 in particular ) use as a base unit a 16x16 macroblock to compress the video, the codec will (roughly) encode a 639x479 ( non mod16 ) and a 640x480 ( mod16 ) video with the same bitrate & quality. So it's better to choose 640x480, since the resolution is bigger.

Of course, you're first concern is really to crop out the black bars ( because 639x479 without black bars is _a lot_ better than 640x480 with a single line black bar )

Well, like I said, 636x444 gets all the black lines. However, since that isn't in x16 I guess I would have to do 624x432. That would suck though, since i'll be losing A LOT of video...

[Manao]

You can resize from 636x444 to 640 x 448.

[Seraphic-]

Yes, but that would "stretch to fit", thus, result in lower quality. But I guess that might be better then 624x432.

[Manao]

You won't watch your video in 636x444, will you ? You'll resize it to full screen, won't you ? Then resizing it to 640x448 before won't hurt a bit. Actually, the resizer in avisynth will do a much better job at upsizing the video than your graphic card's.

Furthermore, it will - very slightly - filter the video. And that can only be good, considering how aliased game videos often are.

[Seraphic-]

Well, no, it isn't meant to be at full screen. I guess some members could watch it at full screen. Myself and I think most would watch at 636x444. (won't it become a blurred mess at full screen at any size?)

Also, thanks to some help, I was able to correctly align the fields. So the raw avi is just about what is found when played on the TV.

[check]

The resizing will produce a slightly incorrect aspect ratio, but you will be hard pressed to see any AR error of udner 5% with normal footage. If there are static GUI elements in your game footage it might be another story, but I'd suggest upsizing to slightly above a mod16 resolution and cropping the few pixels required. CRTs cut off 10% of the sides anyway with overscan, a few pixels won't seriously affect the amount of detail.

[Seraphic-]

639x447 is the best I can do as that is just before the black lines start. I'd still hate to resize at all, but I guess it's only +1 to both fields.

I could get x448, but it looks like there are artifact lines in the Y1 offset.

http://www.seraphicgate.com/1.jpghttp://www.seraphicgate.com/2.jpg

[Seraphic-]

I guess i'll move and make a new post in H.264 as this isn't an XviD issue.

But I cropped the video down to 624x432 just for testing, and after HQ-Insane encode at 2,500kbps, I still found the background of the video to be blurred along with some color loss. I didn't really add any other settings so that could be why.

Thanks for your help