Mjpeg

[Adis]

...

[Dr Mordrid]

Do I sense a stealth advertising campaign?

Also I note you omitted the PICVideo MJPeg codec. Any good reason why?

Dr. Mordrid

[Adis]

I found this picture somewhere and just want to see some comments about it...

PICVideo MJPEG is my favorite codec, it's simply The Best !

[traveller]

What does it mean?
I don't understand this chart as PSNR is not known for me
Could anybody explain?
Thx

[Dr Mordrid]

PSNR = Peak Signal to Noise Ratio

It's a measure of quality. Basically it's a set of calculations done to quantify the differentces between the original image vs. the compressed image.

More info here.....

A small command line PSNR tool can be found near the bottom of the page here;

http://sac-ftp.externet.hu/graph19.html

Just type psnr.exe /? for instructions.

Dr. Mordrid

[KuroNeko]

Visicron? Where's this codec from? Looks expensive

Anyone try the JPG2000 codec from Morgan yet, btw? Any problems?

Neko

[Dr Mordrid]

It's a wavelet based video codec. Wavelets can give high compresson ratios with lower quality loss than DCT based codecs. From what I see on Visicrons website;

http://www.visicron.com

it's mainly a video conferencing codec so far.

The best info I could find is this *.pdf of a slideshow on a Russian site;

http://compression.graphicon.ru/dv/visicron_bsw_codec.pdf

which appears to the be the source of the image above.

Dr. Mordrid

[KuroNeko]

Thanks for the info, Doc. Doesn't seem like this one's ready for NLE yet. Pity, looks promising.

On a different note, could anyone tell me where a good DV codec, like Canopus for instance, would situate on the above graph?

Neko

[Adis]

Originally posted by Dr Mordrid
The best info I could find is this *.pdf of a slideshow on a Russian site;

http://compression.graphicon.ru/dv/visicron_bsw_codec.pdf

which appears to the be the source of the image above.

Yes, it is the source...

[Dr Mordrid]

You can download Matrox's DigiSuite softcodec package from their public FTP. This includes DV type 1, DV type 2, DVCPRO, DVCPRO50 (a 4:2:2 DV codec), MPEG-2 I-frame in an *.AVI wrapper and their M-JPeg codec (.05 - 17.95 mb/s) though the M-JPeg only works at 720x486/576.

Dunno about the strict legalities of using them though....so maybe someone from Matrox can chime in about that before anyone posts a URL.

Dr. Mordrid

[traveller]

Thx Doc very much.
Very informative.

[Flying dutchman]

This Matrox DV softcodec, does it import DV files whilst keeping the original luminance levels (16-235, a.k.a. CCIR601) or does it convert it into 0-255? Most codecs convert the luminance levels to and fro so it looks good on a PC screen.

Unfortunately many video editing programs (such as pinnacle studio 8) do not take this into account and thus merrily produce mpeg-2 files with the full 0-255 range which is not DVD compliant. The darks are too dark and the brights too bright.

[Jkun]

The MainConcept DV codec does support both ranges, and allows selection of which you want.

Adobe has licenced both MainConcept MPEG2 and DV codecs for use in Premiere Pro.

J-kun

[Flying dutchman]

Given the fact that MS DirectX 8 already contains a DV codec, how do you select between the two?

[Dr Mordrid]

MSPro7 can support more than one DV codec as long as they use different fourCC's. A fourCC is a "four character code" used to distinguish codecs.

AFAIK the NTSC 16-235 levels are preserved in the Matrox DigiSuite codec. The RT.X100's codecs are switchable.

The MC MPEG codec used in PPro is a 2 pass encoder.

Dr. Mordrid