Utility to enable YUY2

[Michel Carleer]

Tinnes,
YUY2 is the native format of the RR-G card. I mean, the digitizing chip output is YUY2. On the other hand, YUY2 is the starting format for MPEG compression. So, YUY2 is the best capturing format for on the fly MPEG compression. Once you capture in YUY2, there is no need to go through an intermediate format like, say RGB. So that you gain the time taken by the capture driver to transcode from YUY2 to RGB, and you also gain the time to go from RGB back to YUY2, which has to be done by the MPEG compressor before actually performing the compression. That's all there is to YUY2. You don't really want to store your clip in YUY2, it is simply the most effective format to capture directly in MPEG.
Michka

[Tinnes]

Ok most of that flew straight over my head. Are you saying that with my Matrox Marvel I can capture MPEG on-the-fly, using YUY2 as a starting point?

[KilroY]

Is it feasible in any way to capture to mpeg-2 in realtime (from yuy2), say using an mpeg2 soft codec like Ligos go-motion or something? How fast would your processor have to be, or is this impossible?

[Technoid]

It works and it doesent drop any frames at all compared to RGB or MJPEG!

Question:
In AVI_IO you can chose an compression alghorithm when you capture RGB but i havent been able to chose one with YUY2!

Any sugestions?

------------------
INTEL PIII550 MSI 6163
G400Mill 32MB SGRAM + RRG
SBlive
192 MB RAM CAS2
43GB HDD Space!(Actual 40GB) (13+30 Quantum drives)
Pioneer 104S DVD 10x CD 40x SLOT IN
SONY CRX100E 4/2/24 CDRW

[wkulecz]

Exactly, the reason you want YUV2 capture is to create MPEG. The ULEAD VfW MPEG Capture built into Media Studio Pro 6 will produce what is in my opinion VHS SLP quality in real time from YUV2 captures on a P-III.

Capturing the YUV2 to a RAID array at 640x480 and using a stand alone encoder like Panasonic or Ligos can produce a "true" VHS quality VCD MPEG. Of course the 2G limit is a real PITA here as you're looking at about 27 files for a one hour video.

The realtime SLP quality captures are only about 11MB/min to the disk and are good enough for time shift recording and other non quality critical uses.

In my tests, the initial compression in MJPEG or DV appears to break the MPEG1 encoding process such that VHS SLP to SLP dub is about the best quality one can expect -- only watchable in a dinky 352x240 window on a computer monitor, play it full screen and its trash! Thus we need YUV2 capture option.

RGB captures will "work" for offline encoding as YUV2 to RGB is "lossless" but you're wasting CPU as the captured YUV2 is converted to RGB and output by the marvel to the gomotion codec which promply has to do an RGB to YUV2 conversion before encoding.

--wally.

[Michel Carleer]

Tinnes:
Yes, that's exactly what I am saying. See below and the other replies.

Wkulecz:
I don't like the quality of the GoMotion. In order to be real time, they cut on the time compression efficiency and the resulting stream shows fairly strong pixelation on fast moving scenes. Instead I capture in MPEG4 and recode in MPEG1 afterwards with the Ligos transcoder of MSP6 (Create or Convert video file in File menu). This transcoder is NOT the GoMotion and is of far better quality. You should also use the old version of the Microsoft MPEG4 codec, not the DIVX one which does not produce very good picture quality.

Flying Dutchman:
There is another hidden button in the vcap16.dll file. It is an additional resolution in the resolution dialog of the YUY2 format.
Michka


[This message has been edited by Michel Carleer (edited 27 March 2000).]

[This message has been edited by Michel Carleer (edited 27 March 2000).]

[Flying dutchman]

Michel:

Thanks for mentioning the additional button, I will make it visible.

My way of creating mpeg-1 is the following:
capture at 352x288x25 (PAL) using avi_io, import the whole bunch into a video program like premiere or mspro, then transcode it to mpeg.

Also I've read somewhere that WINVCR will work with the matrox using YUY2 and capture mpeg-1 on the fly!

[Michel Carleer]

Flying Dutchman:
Unfortunately, WINVCR uses the Ligos GoMotion.
I also found by experience that it is better to recompress in MPEG1 afterwards, because the predicted and interpolated frames are of much better quality than with the real time compressors (less pixelation on moving scenes). The Ligos LSX-MPEG transcoder which is on the G400 CD is of far better quality than the GoMotion. The retail version and the MSP6 plug-in are even faster than the Matrox version (10 min clip takes ~ 10 min to transcode).
Michka

[ccc]

hi Fl. Dutchman

I tried the patch u've written with the French version of the VT. The patch applies, and I got the YUV2 choice, but....
it totally crashes my PC ;c (it even resets itself
I am downloading the English version ... hope that 'll work

Thx!

[RBryant]

Yeah, it totally crashes my 1.52 English version of the Video Tools...

Is this patch compatible with the Macrovision patch? Maybe that is what is causing the problem...

[Tinnes]

No the Macrovision crack is not the problem. I have the latest Matrox Marvel G400 drivers and the latest version of VT. And the Macrovision crack and the YUY2 enable util work fine togther on my puter.

[Flying dutchman]

It should not interfere with the macrovision patch. I'm running it myself (version 1.52). I would recomment applying the macrovision patch first, and subsequently the YUY2 patch.

I can't explain the crash; Did you make sure no other program than YUY2.EXE was running when you made the patch? Please mind that it works with the Windows 95/98 versions only, NOT NT !!!

YUY2.EXE searches for a specific byte sequence in the file: 40H+80H+26H+'YUY2'
which is the code for an invisible radio button with the text "&YUY2". As soon as it finds this sequence, it changes the 40H into 50H which makes the button visible.

This byte sequence only occurs once in vcap16.dll. If you do a binary compare between the original and the modified vcap16, you should find that they differ in one byte only.

By the way, Matrox probably have their reason to disable YUY2 in this file. Maybe some older versions of the DLL really crash, I don't know?

I am working on a new version of the program that will also make the "QCIF" button visible and that will make a backup copy of the original DLL. Expect it sometime next week!

[ccc]

Damn , I installed the English version of Video tools to check , and it crashes the same way ;(

Anyone the same problem ?
thx!

[ccc]

Hi,

Installed english version of Vt, but still hangs the machine and resets ;(
anyone same problem ?
thx!

[RBryant]

Yeah, when I first installed the YUY2 patch everything worked fine with the Macrovision patched 1.52 so I guess it is neither patch causing the problem...

But one day I ran AVI_IO and my system hung... then I rebooted and tried to run PC-VCR with the same result... The only way I could get it to run again was to run Matrox's Uninstaller and then reboot and install the latest PD (5.52) and VT (1.52).
I then ran PC-VCR and AVI_IO no problem. Then I applied the Macrovision patch and still no problem. Then I ran the YUY2 patch and got the hang again. Is it possible that some registry entry got changed somewhere and now the Rainbow Runner gets confused because of "state" of being in YUY2 mode? I'm not sure what is causing it. But I will probably re-ghost my machine tonight and see if I can garner any more clues...