YV12: mpeg2dec, mpeg2dec2 and mpeg3dec developers

[Wilbert]

@Dividee, tbarry and MarcFD,

Could anyone of you make a mpeg2dec version which outputs to YV12 by default (or by option)? (I understood that MarcFD stopped developing for a while ...) So that we can make some speed tests (YV12 versus YV12->YUY2->YV12), for dvd to DivX/Xvid. That would be really great ...

[sh0dan]

Though a YV12 decoder would be a good thing for testing, there is no real speed increase to be expected yet, since VDub doesn't support YV12 data yet.

So instead of:

YV12 (MPEG2) -> YUY2 (decoder) -> YUY2 (avisynth) -> YUY2 (vdub) -> YV12 (Xvid).

we still have:

YV12 (MPEG2) -> YV12 (avisynth) -> YUY2 (vdub) -> YV12 (Xvid).

Until this is resolved, you cannot expect a speed increase. Furthermore many YV12 filters still need optimizations to perform at their best.

I tried to find Marc FD's sources, but haven't been succesful yet.

[Wilbert]

Sh0dan, haven't you seen the modified version of pulco-citron (see for example in the thread in the development section). You responded to his message this morning, in which he says:
VirtualDubMod already passes YV12 unaltered to the decompressor if both the source and the output report to support this format (is this what you mean ?)
His version can be found in the second url of his first post in that thread.

[sh0dan]

I get a lot of crashes in DivX, when using YV12, but it does work (Xvid DOES recieve data as YV12 - I tested this on a debug build).
Maybe AviSynth is giving DivX wrong information, or DivX is simply buggy.

[trbarry]

The sources to my version of DVD2AVI and MPEG2DEC are in the Sourceforge save-oe project, and also at:

www.trbarry.com/DVD2AVIT3.zip and
www.trbarry.com/MPEG2DEC2.zip

I think Store.cpp converts from YV12 to YUY2.

Also, I'm working on a version of TomsMoComp for ffdshow (if I can ever build the darn thing) that works in YV12. After that I'll probably make a YV12 SimpleResize version which I expect to go a bit faster than YUY2. I'm not sure after that.

- Tom

[sh0dan]

Yes, it seems like the conversion in store.cpp should be altered. I'll see if I get the time for it.

[Marc FD]

Argh XD i thought you'ld need more time to get to serious YV12 stuff :)

Hey, no pb, i'm pretty familiar with the source now, i'll do it.
just wait for 10 hours (to sleep) + 2 to 6 hours (to eat & code), okay ;)

I have not started to test YV12 in Avisynth, because i thought VDub couldn't handle it before a while, but you're so fast.

You know, developpement is like a drug. you've tasted it, and after you can't stop it ^^

who would refuse a more than 20% faster MPEG-2 decoder ?
not me.

back in 12 to 16 hours,
MarcFD

PS : maybe less, but i need to test it, and my beta 7 version introduce some new features, like custom PP... so it would be a testing version first.

[Marc FD]

10 hours ^^

okay i've done it. here you have MPEG2Dec3 pre-beta 7 with YV12 support.
everything should work, but i've only tested PP.

Crop works ! (croping is a very good test to check a filter)
Avisynth's resampler works ! (great job sh0dan)

Frameserving tests : (script is LoadPlug()/MPEG2Source() only)

Vdub decode using the DivX 5.02 codec (as expected)
WMP 8 crash.
BSPlayer crash.
Zoomplayer works.

VDub with "Direct Stream Copy" Preview :
YUY2 version : ~60 fps
YV12 version : ~75 fps
(Athlon XP 1600+, 256 Mo DDR)

so it's about 25% faster, as expected.
but the DivX decoder is slow and/or is converting in RGB32, because it's slower than MPEG2Dec3 internal convertions :

VDub with "Fast Recompress" Preview :
YUY2 version : ~50 fps (raw YUY2)
YV12 version : ~40 fps (decoded by DivX5.02)

that's what i've noticed so far.

BTW, ConvertToYUY2/ConvertToRGB doesn't work. i guess there's no implemented YV12 support in colorspace convertions yet. what about using XviD's ones ??

I hope the VDub Mod will have YV12 ultrafast-compress soon, i'd really like to see that working ^^

(attached : "MPEG2Dec3 YV12.zip")

[Wilbert]

MarcFD, try this modified version: alpha0.31 (http://sourceforge.net/projects/virtualdubmpg2/). Some info (http://forum.doom9.org/showthread.php?s=&threadid=33586&pagenumber=2).

There's one thing I forgot. Dvd2avi outputs to YUY2 or RGB only, isn't it (there's no option in dvd2avi for saving in YV12)? So the last thing we need is a modified version of dvd2avi?

[sh0dan]

@Wilbert:

DVD2AVI shouldn't matter, if you import the d2v file into AviSynth. The decoder should be the only thing that should be modified. DVD2AVI doesn't touch the video material when the d2v is created.

(unless I'm mistaking?)

[sh0dan]

@MarcFD: Great work man!!! Hope it gets approved soon!

When using Avery's Vdub, the image information is converted to YUY2 before it is sent to the DivX (or Xvid) compressor, when using "Fast recompress".
The VdubMod attampts to pass YV12, which only works partially. At least on my machine, I'm getting crashes in DIVX.DLL, when I use YV12 passing. I don't know if I'm passing the wrong data to DivX or if DivX is buggy. Both are equally possible.

ConvertToYUY2 _should_ work, when the source is YV12. I've been using it a lot for tests.
ConvertToYV12 _should_ work with all colorspaces. It is not optimized by any means though (and RGB sources are converted to YUY2 first).
Yes, the XVID routines seem very obvious to use - fast, very well tested. Only problem is that they have to be converted from NASM -> MASM.

Oh - and the current ConvertToYV12 has broken interlaced chroma conversion, so you don't have to mention that - I'm aware of it!

[Nic]

sh0dan is correct about d2a. :) YV12 support is great for MPEGDecoder.dll (at present I have to split the YV12 frame into its y,u&v components and then convert it to YUY2. Going straight out with YV12 makes things lots easier & v.quick.

The modification to VDub should only be tiny (?) Ill check out the source & have a look.

-Nic

[sh0dan]

The Vdub mod does it now, but the real issue is to make Vdub(mod) open YV12 without asking for a decompressor. That way there is no need for DivX anymore.
Vdub will not be able to preview or apply filters, but I think that would be an ok solution until it can properly decompress YV12.

[Wilbert]

sh0dan is correct about d2a.
Can I ask something about this ... What is the purpose of that colorspace setting in d2a? What is the difference if you set it to YUY2 or RGB? What happens if you leave it at YUY2 and try to open the d2v file in VFAPI for example?

[trbarry]

10 hours ^^

okay i've done it. here you have MPEG2Dec3 pre-beta 7 with YV12 support.
everything should work, but i've only tested PP.

Excellent! ;)

Let me see if I know where we stand then on YV12 support. Currently we can:

- Pass YV12 directly to Avisynth with no conversion using MPEG2DEC3

- Do ConvertToxxx in Avisynth as needed (except ConvertToRGB).

- Use Avisynth Crop and various resize (except my SimpleResize)

- Pass YV21 to vdub only if we are using fast recompress and going to Divx 5, not Xvid.

Is that pretty much correct and current?


Wilbert -

The RGB/YUY2 setting is honored by VFAPI but ignored by MPEG2DECx.

- Tom

[Wilbert]

The RGB/YUY2 setting is honored by VFAPI but ignored by MPEG2DECx.
Ok, thanks.
Currently we can: (...)
Yes, except the last one:
Pass YV12 to vdub only if we are using fast recompress and going to Divx 5, not Xvid.
As I understand it, this is also true when encoding to Xvid or DivX3/4. But DivX5 is needed to decompress the avi when opening it in Virtual Dub modified (DivX4 and Xvid are not capable of doing this).

@MarcFD,

Did you actually attach the file?

[trbarry]

As I understand it, this is also true when encoding to Xvid or DivX3/4. But DivX5 is needed to decompress the avi when opening it in Virtual Dub modified (DivX4 and Xvid are not capable of doing this).

Not sure I understood this. Are you saying I could already set vdub to fast recompress and pass the YV12 clip to Xvid? (without any colorspace conversion?)

- Tom

[Wilbert]

Yes, but you need to install DivX5 for that. Maybe Sh0dan can explain it better :)

[Alestrix]

Now that everyone is hot on YV12 it's time we somehow can get our hands on Marc's mpeg2dec3b7.... Is the Mod busy or did the upload not work?
@Marc: Can you upload the file to your web page?

Can't wait trying it,
Alex

[Guest]

Mod was out of town and when he got home found out about a death in the family. Attachments have now been approved.

[trbarry]

Donald -

Very sorry to hear that.

- Tom

[trbarry]

Can anyone point out a very small simple example source of a standalone Avisynth filter that works in YV12 mode.

I'd like to study one before modifying TomsMoComp if possible. As close as possible to something line Ben RG's original sample filter (http://math.berkeley.edu/~benrg/avisynth-extensions.html), but for YV12.

- Tom

[Koepi]

@Donald:
my "condolescence" (dunno the right word for that), I am sorry for your loss.

@All:
Hm, it doesn't work for me, my AVS looks like this:

SetMemoryMax(40)
LoadPlugin("D:\Video_TS\sbc-ripping\avisynth\mpeg2dec3 YV12.dll")
mpeg2source("D:\Video_TS\5thElement\5thElement.d2v")

Loading it in vdub-mp2 or mediaplayer just makes the program disappear without further notice.

Any idea what's happening? Isn't avisynth 2.06 supporting yv12? Which AVS version do I need? Maybe I need another iDCT-number?

Thanks and best regards,
Koepi

[Marc FD]

@Donald
mes condoleances.

>Isn't avisynth 2.06 supporting yv12? Which AVS version do I need?

no, as far as i know only the alpha 2.5 work with YV12.

i'm gonna try how fast i can transode with :

MPEG2dec3 (YV12) -> Avisynth resample to 640x480 (YV12) -> XviD (YV12)

[sh0dan]

ok - I did some heavy vdub/xvid debugging, and have good news!

I have HACKED (very bad hack even) an XVID version together, that claims it is capable of decoding YV12. It isn't! But the trick is, that this enables you to use "Fast Repack" in a modified VirtualDubMPG2 i also made.

This makes DivX5 unneeded for those who doesn't want it. I made this mostly for test purposes. In general I would still recommend using DivX5!

The most important change was a small change in VirtualDubMPG2, that enabled YV12. In the official version, all data is still converted back and forth between YV12 and YVYU, because of the way it opened the file. That why there was no speed gain!

Techinical explanation - you may skip this:When Virtual Dub attempts to do "Fast recompress", it tries different codecs on the source. If the AviSynth script has YV12 for input it will fail on these. What VFW then tries is to get any decompressor to accept YV12 and then return it it the format that vdub requests. This is what DivX5 (and the hacked Xvid) does. It'll decompress the YV12 data to something that Vdub requests.
The problem was that VirtualDubMPG2 requests YVUV _before_ requesting Yv12. Therefore DivX5 kicks in and decompresses the YV12 data to YVUV, which XVID (and of course DivX) also accepts as input formats, when compressing. The problem besides the slowdown is that DivX5 seems to have buggy YV12->YVYU conversion, causing crashes.
The modified VirtualDubMPG2 now requests YV12 before any formats, and the therefore DivX5 never touches the video when "Fast Recompress" is enabled.

If you're using DivX5: (recommended!)
- Use the VirtualDubMPG2 in the "Alpha Package" on the alpha site.
- Use fast recompress, and your data should be passed as YV12.
- You should be able to preview your data most places.

If you don't use DivX5
- Manually install the Xvid.dll hack from the "Alpha Package" (if you don't know how, don't bother, stick with DivX5)
- Open the YV12 file in the modified VirtualDubMPG2 (you probably cannot open it elsewhere).
- Don't mind you cannot see the images, when dragging.
- Use "Fast recompress"
- Hopefully your result is ok.

[ARDA]

@Donald
Mis más sinceras condolencias

Arda

[sh0dan]

Originally posted by trbarry
Can anyone point out a very small simple example source of a standalone Avisynth filter that works in YV12 mode.


I've converted some internal filters. Just download the source.

Small filter you could look at:

Levels (levels.cpp)
HSIAdjust (levels.cpp)
StackVertical (combine.cpp)

Usually you have three loops - one for each plane.
Many things become clear (hopefully) if you look at the new avisynth.h and the documentation on my alpha site. Many things are still the same, but with small adjustsments.

Just ask away.

[EDIT] Just converted Ben's Invert filter. I haven't tested it, but I probably only made typo's. You can find a link to it in the development section on the alpha page. A thing that may surprise you is, that it still works with YUY2 and RGB data!

[Koepi]

Ok, got it working with Avisynth2.5 (http://cultact-server.novi.dk/kpo/avisynth/avisynth_alpha.html) and opening the AVS with vdub_mp2 (after installing divx5 [%&$§&%]). Cropping [Crop(2,74,716,432)] after that still works.

EDIT:

Ok, I found out that only vertical resolution can get resized :-/
Is the downsampling/upsampling in horizontal direction really so much different?

Thanks a million again,

regards,
Koepi

[sh0dan]

@Koepi:
Please use mod4 resolutions. This will be a YV12 requirement, but isn't enforced yet!

Did you get the modified vdub_mp2 version? Otherwise it will not be clean YV12.

Horizontal resizing should work in the version you got (and yes, it is _very_ different) - Horizontal took many times longer to implement as vertical. Try a mod8 resolution (both before and after the resizer).

[Rrrough]

sh0dan,

thanx for your mod on VirtualDubMPG2, will try it right away with Avisynth 2.5. please excuse a probably stupid question : why isn't xvid capable of decoding yv12 as is ? isn't it also encoding in yv12 ?
Hopefully we'll find your modifications soon in VirtualDubMod !

cheers

[sh0dan]

Otherwise I'm off to bed. I'll probably be gone for a couple of days now. As you get on with the testing, remember this is alpha software. Most of it is unoptimized, so don't put too much into benchmarking. There are also still some bugs to be resolved, and some missing functions.

@Donald: I'm very sorry to hear that. I hope you take the time needed for such an event. Take care!

[sh0dan]

Originally posted by Rrrough
why isn't xvid capable of decoding yv12 as is ? isn't it also encoding in yv12 ?

It's capable of decoding Xvid. It just doesn't touch YV12 data, when it comes to XVid for decompression. Adding proper conversion is not a job for me, but most of the code is there.

[Koepi]

Ok, encoding is now running at ~14fps (WOW! that's speed increase... even if your xvid.dll spits out so much debug info, doesn't use EPZS, ... ;) )

Fetched the "Alpha package", modified the AVS to look like this:

SetMemoryMax(64)
LoadPlugin("D:\Video_TS\sbc-ripping\avisynth\mpeg2dec3 YV12.dll")
mpeg2source("D:\Video_TS\5thElement\5thElement-yv12.d2v")
Crop(4,74,712,432)
Trim(0,174846).BicubicResize(640,272,0,0.5)+Trim(174846,0).BilinearResize(640,272)

Set to fast recompress, usual xvid setup (at least for me ;) ), unfortunately no unfilter and avsmonitor filters available - but the speed is there. Let's see how this encoding will look like after the 2nd pass, but it looks promising at least from the debugview output...

Thanks for all your great work,

best regards,
Koepi

[Rrrough]

thanx for clarifying. sleep well. ;)

[Alestrix]

@Donald
Sorry to hear that, I know what it's like. Hope you were not offended by my "call for the mod"...

sh0dan,
outstanding work! Did a simple avs:

LoadPlugin("C:\PROGRA~1\SOUNDV~1\GORDIA~1\mpeg2dec3 YV12.dll")
mpeg2source("D:\Eigene Dateien\Video\DVD\intermediate\shrek\shrek.d2v")
Crop(5,5,712,566)
LanczosResize(704,384)

and I can even watch it in MPC (I think I had to set ffdshow to handle raw video first). Also thanks to Marc!!! for his quick adaptation of Mpeg2Dec3!
Encoding to xvid works fine in the modified VirtualDubMpeg2 - I only found a tiny bug in Avisynth's handling of YV12 in crop/resize. When substitutung the Crop and Resize statement to LanczosResize(704,384,5,5,712,566) (which works fine in YUY2), the chrominance information is shifted up by a few pixels (my guess is 4). (in the latter case I also tried mod4 values with the same effect)
Could it also be that B-frame support (I know, I'm, overdoing things ;)) is gone in your modified xvid.dll? 'cause even when working in YUY2 the B-frame options are grayed out in XviD config. Maybe I should install DX50 (lite should do the job) again and use the standard xvid.dll with your modified VDub? Would that still pass YV12 directly to the XviD-encoder?

...maybe a few things I should test in the morning...

Again, thanks for the great work!

- Alex

[Rrrough]

@Alestrix

I think it's made of the stable branch (no bframes, no qpel...). take a look at the about box.

@Koepi

if it's not done already, could you please propose sh0dan's mods to CVS and/or use them for your builds ? that way we could also test dev-builds without having to deal with DivX5...

thanx alot, sh0dan, it's working real fine here, ~9 fps instead of ~6-7 fps (...slooow machine...)

cheers

[hakko504]

Unfortunately it doesn't look like YV12 is enabled, at least the release notes (http://sourceforge.net/project/shownotes.php?release_id=119822) don't mention it.

[Alestrix]

Originally posted by Rrrough
@Koepi

if it's not done already, could you please propose sh0dan's mods to CVS and/or use them for your builds ? that way we could also test dev-builds without having to deal with DivX5...

I got it to work with Koepi's latest XviD in GraphEdit (with B-frames):
Filesource (the avs) -> Xvid Compressor -> OggMuxer -> FileWriter
I used trombetworks' FilterConfigurator in the graph to configure the XviD compressor.

A little bit OT:
EDIT:decided to move this here (http://forum.doom9.org/showthread.php?s=&threadid=37096).

- Alex

[Koepi]

Originally posted by Rrrough
@Koepi
if it's not done already, could you please propose sh0dan's mods to CVS and/or use them for your builds ? that way we could also test dev-builds without having to deal with DivX5...


I'd love to add that to my builds but unfortunately I don't know what sh0dan changed, he has to send me the modifications so I can apply them... :)

But I'd prefer that as well, since his build is giving me worse compression than my actual dev-api-3 build+qpel,... :) Still I'm looking forward to see the results of the plain YV12 chain in ~2hrs.

Regards
Koepi

[Rrrough]

@Alestrix
I got it to work with Koepi's latest XviD in GraphEdit (with B-frames): gonna try it ! I didn't notice Trombettwork's FilterConfigurator yet, only seen the ChannelDownmixer. thanx for the hint. still it would be more comfortable modding xvid in general, but I guess that will take a while.

@Koepi
I'd love to add that to my builds but unfortunately I don't know what sh0dan changed, he has to send me the modifications so I can apply them... I hope sh0dan is listening (when he returns).
Still I'm looking forward to see the results of the plain YV12 chain in ~2hrs. let us know about your results.

cheers

[Koepi]

Jesus, it makes a difference.
It's faster. One pro.
The colours stay more "natural" due to "no unnecessary interpolations"! Another pro.

It's "very" ;) complicated and we can just use a special xvid build. That's a con ;)

Great work! This really is amazing. If I can get it to work with usual xvid builds it will be even more interesting. I hope this modification makes it in all our tools.

Best regards
Koepi

[int 21h]

I'm sort of lost as to why we need a special XviD build, if XviD accepts YV12, why do we need to make it appear like it is capable of decoding YV12? Only for the VirtualDub preview correct? Why not just disable to preview? I guess its related to Vdub requesting an appropriate decompressor?

Anyway, you should all chime in here:

http://virtualdub.everwicked.com/index.php?act=ST&f=11&t=449

To let Mr. Lee know how much people want this idea implemented 'properly'.

[sh0dan]

Originally posted by Koepi
I'd love to add that to my builds but unfortunately I don't know what sh0dan changed, he has to send me the modifications so I can apply them... :)


I included the modified codec.cpp in the alpha package. Basicly, the changes are:
decompress_query():
if (inhdr->biCompression == FOURCC_YV12) {
DEBUG("\n***** Was asked for YV12 decompression.\n");
return ICERR_OK;
}

Which basicly means: If a program asks if YV12 input is ok, return ok.

decompress_get_format():
if (lpbiInput->bmiHeader.biCompression == FOURCC_YV12) {
memcpy(outhdr, inhdr, sizeof(BITMAPINFOHEADER));
DEBUG("\n***** returned YV12 decompression.\n");
return ICERR_OK;
}

Which translates into: If a program asks for a decompression destination format, and input is YV12, ALWAYS return the same format (YV12). This may be ignored!

decompress():
{ char tmp[120]; wsprintf(tmp, "\ninput colorspace:0x%08x %s\n", (icd->lpbiInput->biCompression),&icd->lpbiInput->biCompression); OutputDebugString(tmp); }
{ char tmp[120]; wsprintf(tmp, "output colorspace:0x%08x %s\n", (icd->lpbiOutput->biCompression),&icd->lpbiOutput->biCompression); OutputDebugString(tmp); }

if (icd->lpbiInput->biCompression == FOURCC_YV12) {
DEBUG("input=yv12\n");
if (icd->lpbiOutput->biCompression == FOURCC_YV12) {
DEBUG("copying\n");
memcpy(frame.image,codec->dhandle,icd->lpbiInput->biSizeImage);
}
return ICERR_OK;
}

This is the hacky part! Basicly: If input is YV12 and output is YV12 the source frame is copied directly to the destination frame. If it isn't, nothing is done to the destination (ie. uninialized data)

This should be: If input==output==yv12, then copy as it is doing now. Otherwise do a colorspace conversion to the destination format and return that.

[sh0dan]

Originally posted by Alestrix
I only found a tiny bug in Avisynth's handling of YV12 in crop/resize. When substitutung the Crop and Resize statement to LanczosResize(704,384,5,5,712,566) (which works fine in YUY2), the chrominance information is shifted up by a few pixels (my guess is 4).

I have seen the same result myself (and a green pixel topleft).
Besides that, the crop functions in resize will probably be removed, since it is slower and doesn't work as well as crop().

Could it also be that B-frame support (I know, I'm, overdoing things ;)) is gone in your modified xvid.dll? 'cause even when working in YUY2 the B-frame options are grayed out in XviD config. Maybe I should install DX50 (lite should do the job) again and use the standard xvid.dll with your modified VDub? Would that still pass YV12 directly to the XviD-encoder?

Yes, it'll still work.
You should probably install DivX for testing - it'll enable preview, and you still get the speed - then you can use your own favorite xvid distributor.
The xvid hack is only temporary, and since I have no idea of which compile-defines to enable. I hope someone else will do this job, or vdubmod will take up the challenge to open yv12 data raw.

[Nic]

Got no idea if I have added the hack properly, because im trying to do about 100 things at work right now:
http://nic.dnsalias.com/XviD_Install_Hack.exe
Same as my build from today but with the hack installed...hope I did it right.

-Nic

[sh0dan]

OK - new alpha up for you speed freaks.

I rewrote the YV12 horizontal resizer, and it is MUCH faster now - even faster than YUY2.

This also seems to have solved the green pixel (chroma offset) bug - on my computer at least.

Edit: Oh - forgot - YV12 horizontal resizing requires ISSE - I'll do an MMX version soon.

Edit2: Finished the MMX-version. People with old machines can redownload todays alpha.

[Marc FD]

wow. 30 fps with a BicubicResize. and you say it could be even faster ?
just need to wait that vlad finish c3d YV12 (he's working on it right now) and i could speed up by more than 50% my XviD encodes ^^

BTW, if s.o. want to try a real encode, and need filtering, the PP in MPEG2Dec3 is working (it's YV12 based ^^). and you can use custom PP using cpu2. ex : chroma only filtering : cpu2="oxoxox"

[iago]

Hello everyone,

All I can say is that's really striking!

MPEG2Dec3 YV12
Avs 2.5 today's latest alpha
VirtualDubMpg2 modified

Averaging ~12 fps on my poor machine with BicubicResize :). Thanks everyone putting effort on this great work!

kindest regards,
iago


@Tom,

I hope we'll also have the YV12 version of your great UnFilter soon! ;)

[ErMaC]

Guys, I'd really love to try some of this stuff out, but I don't want to put my normal AVS stuff in jeopardy, so here's a question.
What exactly do I need to start testing this stuff and using it and keep it in an isolated environment?
Can I have a separate VDub directory with the hacked VDub, the new v2.5 AVISynth DLL, the new MPEG2DEC DLL, and the hacked Xvid DLL, and will everything work when I use that VDub from that directory without interfering with my other stuff?

[Emp3r0r]

Ermac, you need two computers to reliably have something to fall back on. Have one computer with beta stuff (2.5 YV12 is super fast on a XEON) and one with avisynth 2. I don't think Avisynth 2.5 alpha autoloads filters most likely because of alpha status so you should wait on mission critical machines.