Avi to YUV 4:2:0

[ImJustHere]

I need to create yuv 4:2:0 elementary bitstreams out of avi's. Is this possible? I'm new to this so the simpler the better. I was hoping there was software out there that would do this for me. Something with a gui that doesn't need compiled. I'm really under a time crunch here so any help would be greatly appreciated.

Thank you,

Chris

[ImJustHere]

sorry, I didn't mean for this to go through twice. My computer hung up and I didn't think it went through.

[Cornucopia]

There really aren't any "standardized" uncompressed elementary YUV 4:2:0 video bitstream formats (unless you count some Unix types) that are not either wrapped in a QT or AVI container (even without audio) or as a raw DV stream or elementary MPEG stream. Most times, when AVI/QT isn't part of the picture, the stream is given as a sequence of stills (all consecutively numbered in 1 folder).

Scott

[ImJustHere]

I'm trying to make files that I can run through my h.264 encoder. The ones I have that I know work end in .yuv and arn't recognized by my computer as video files. I downloaded a clip from the web that said it was yuv 4:2:0 and ended with the extension .qcif and was able to run it through my compiler also. What kind of files do you think they are? And how do I go about making them?

Chris

[ImJustHere]

I can run dv streams through my compiler but I get garbage out.

[Cornucopia]

Open both the .yuv and the .qcif files in a video stream inpection program like Gspot. It may surprise you by telling you that what you've got is actually a renamed .AVI.

QCIF usually stands for Quarter-CIF. CIF (aka SIF) stands for Common Interchange Format, IIRC. These are both fairly standardized computer video sizes.
CIF = 1/4 D1, or 352 x 240/288 (NTSC or PAL size)
QCIF = 1/4 (1/4 D1) or 1/16 D1, or 176 x 112/144 (why 112 and not 120?--has to be a multiple of 16)

If your source is QCIF (176x112), what could ever be gained quality-wise by encoding to h.264? Maybe slightly lowered bitrate...


reV

DV streams would have to first be Inverse DCT decoded and uncompressed and Colorspace converted (4:1:1 --> 4:2:0) before being compatible with YUV 4:2:0.

Scott

[ImJustHere]

Gspot doesn't recognize either file. I didn't think they were avi's. They arn't supposed to have headers or anything in them to I assumed they were elemental bitstreams. What else could they be? I'm making source material to test a chip my work is developing so these arn't practical files I'm trying to make. I'm just trying to break their decoder.

Chris

[Cornucopia]

Well, I noticed from Google search that ffmpeg encoder mentions raw yuv as an intermediate type file/stream. However, if you look at their list of acceptable input/output file formats, yuv is NOT listed. Sounds proprietary to me, or using some unix/linux byteordering convention (one I don't know).

Scott

[Soopafresh]

If you want h264 files in the end, read and download the full package.

http://forum.doom9.org/showthread.php?t=89979

Whoops, didn't read the full thread. Nevermind.

[ImJustHere]

I think that's what I'm using. It was given to me but I think it's compiled from the most current x264 build. I found a site that gives an outline of how they made the kind of file I need -

The raw video has been obtained by capturing the scene with a regular PAL DV camera (720x576@25frames/s) and storing the walk scene to a DV AVI file. The DV AVI file was then further decoded, colour converted from 4:2:2 format to 4:2:0 format and de-interlaced. The de-interlacing was performed by replacing every odd pixel line by the average of the pixel lines above and below.

I can make the dv avi but don't understand how to further decode it. Another site that had the right kind of files sated "The sequences are all in the common YUV 4:2:0 format, widely used in the video research community." What does that mean!?!

[Cornucopia]

"Video Research"--Universities, experimenting. Unix. Not "industry standard" (that would be going through bodies like SMPTE, etc). What I thought.

Check out that Russian site (don't recall it now) doing all the evaluative work-PSNR, etc. Email one of the head faculty there. Probably understands English and could direct you further...

Scott

[ImJustHere]

It's called YUV 420 planar. Does this mean anything to anyone? Can someone tell me how to make it?

Chris