Test Pattern, YUV converter, Re: [M4IF Technotes] Downloadable standard MPEG test sequences

[Robert Bleidt]

I've posted a conversion tool to take yuv sequences like those from VQEG 
and make AVI files at www.streamcrest.com - click on the "MPEG-4 
Information" button.
It will output AVIs in either UYVY yuv format (which is absolutely 
transparent) or in RGB. You should be careful when using a yuv AVI file, as 
almost all tools on the PC will try to read it using the msyuv.dll codec. 
For some reason, the version of this DLL supplied with Win2000 only does a 
16-bit conversion to RGB, which is the internal format of many PC tools. So 
by using the most transparent mode for converting the sequence, I 
inadvertently cored it to five bits per pixel. I then used RGB for my work, 
but I hear that WinXP ships a new version of msyuv.dll that maintains full 
precision.
I felt a little more comfortable using my transcoding than Microsoft's, 
since I know what's happening. This program uses linear interpolation of 
adjacent pixels to get the missing chroma samples, R 656 color space, and 
32-bit integer arithmetic with rounding. If anyone is interested, I can 
send you the source to the transcoding routine.
There's also a program posted that makes a standard test pattern I've used. 
There's no great science behind it, but it's easily portable - download an 
100KB .exe and run it. It may look like a torture-test from the web site 
picture - but a look at the Q values on several MPEG-2 encoders shows it's 
substantially "easier" than mobile and calendar.
At 08:49 AM 7/11/2023 +0200, you wrote:
>Ben,
>
> >     Another issue I have with the current test sequences is almost no
> > real-world apps can read the .yuv format,
>
>I know 2 players for .yuv files. One is available on line (
>http://thanglong.ece.jhu.edu/Course/643/YUVplayer.exe ) and I can send you
>the other directly if you need to.
>
> > and there aren't any tools I know
> > of that can do a native colorspace conversion between .yuv and .mov or
>.avi.
>
>For .yuv to .avi conversion, I generally use Microsoft's tool (
>yuvtoavi.exe ). There is also another tool with GUI (
>http://www.ee.surrey.ac.uk/Personal/S.Worrall/dloads/yuv2avi.zip ), but I
>had some strange results ( washed colors ) when I tested it a while ago. The
>same author ( s.worrall   eim.surrey.ac.uk ) also provided a very useful tool
>to convert VQEG's YUV 4:2:2 files to AVI. This is the only one I found.
>
>Regards,
>
>Olivier Amato
>
>
>
>_______________________________________________
>Technotes mailing list
>Technotes   lists.m4if.org
>http://lists.m4if.org/mailman/listinfo/technotes

Robert Bleidt   - Image Circuits, Inc. - rbleidt   hdtv.com