Vegas DV codec vs Matrox DV codec test inside

[marc5532]

I have heard good things about the Matrox DV codec (chroma interpolation), so I have done a comparison with the Vegas internal codec (decoding only). These tests were on a 4.2.0 PAL footage. The 300% zoom on pictures is made in photoshop to see more details:

fix camcorder, progressive recording:





As you can see, the Matrox codec does a really good job, but there is a problem in interlaced.


next test, light in a club, interlaced:





Seems the Matrox codec see 4 fields (???????), where the Vegas codec see only 2 normals fields. The image from the Vegas codec can be de-interlaced properly, but not the one from the Matrox codec. Tested, in Vegas, Virtualdub, Win2K, WinXP, but the Matrox gives this bizzare 4 fields in interlaced. I have also tested moving images in progressive mode and in some pictures, I've seen lines artefacts (less evident). I would like to use this Matrox Codec as my new decoding codec (as you I suppose) but I can't find a solution. If you have one, let me know.

Here is the settings in the Matrox codec:

[scharky]

For progressive footage, it seems that the matrox codec is applying chroma smoothing, hence the clean lines. You can do this as well with Vegas, but you have to tell it to do it, using the chroma smoothing filter.

[Spot]

That's true, Sony prefers to give you choices. Not that Matrox is bad, far from it, they're VERY methodical there. (did you see their response to Canopus? )Anyway, try this test again with the Chroma Blur applied, I'd like to see the diff on those same two frames.

[marc5532]

here it is:

Vegas Codec with 1.500 vertical chroma blur:



and Matrox codec again:



As you can see, the Matrox codec is the winner. It seems it uses a real interpolation and no blur. You can try all the settings you want in the chroma blur, the Vegas codec is always inferior.

[Barry_Green]

Well, inferior is a harsh word to use. The Vegas codec displays the footage as it's actually recorded. The matrox is interpreting the footage and blurring the chroma channel. The Vegas codec is more "true", the Matrox codec is not truly representing the compressed data. Either will look basically identical on a television, where you're seeing the difference is on a computer screen.

For doing something like an HD up-rez, the Matrox codec is indeed quite a bit better, the chroma smoothing makes a huge difference in up-rezzing. And the Matrox codec is much faster than using Chroma Blur.

[Barry_Green]

P.S. You can see a page full of this same discussion (but with different players) over on Michael Phillips' 24p.com site, where he compares the FCP codec against the Avid. FCP's acts like Vegas', and Avid acts like Matrox's.

[scharky]

marc, I have had increadible results using the chroma blur, however, it is better to use the horizontal chroma blur on footage like this. i guarantee that you can get rid of that red flaring 100% with the horizontal blur. It is true however, that using the matrox codec would be faster.

[marc5532]

Yes, but blur is blur, and the more you apply blur, the more the color bleed. I have no time to post all my results, but if I apply a chroma blur (I have tested a lot of settings, in horizontal, vertical, both) to make the image as smooth as the same image decoded with the matrox codec, the chroma blur make always more bleed than the Matrox codec. The Matrox codec seems to interpolate, it is not a blur.

It can make a difference when you up rez, but not only, I think it can be useful when you make chroma key or intensive color corrections.

Remember that I have done all test in 4.2.0 PAL. I don't know how is the comparison in 4.1.1 NTSC.

[Barry_Green]

Right - Marc's in PAL territory, so vertical blur is the right thing to do. PAL has twice the horizontal color resolution, and half the vertical color resolution, of NTSC: so you'd want to blur vertically on PAL footage. You'd want to blur horizontally on NTSC footage.

[David Jimerson]

[quote author=marc5532 link=board=Vegas;num=1100670559;start=0#3 date=11/16/04 at 22:38:05]
As you can see, the Matrox codec is the winner. It seems it uses a real interpolation and no blur. You can try all the settings you want in the chroma blur, the Vegas codec is always inferior.[/quote]

I can't say as I agree. The difference here, if any, is negligible.