Page 1 of 1

dxv issue

Posted: Fri Mar 02, 2012 12:03
by bildwerk
Hey guys,

gery from 4youreye found a bug in the dxv codec. i could reproduce it on my computer as well. the codec creates a little bit of noise on high contrast edges.
i uploaded two videos (full-hd) of the same animation (just a logo rotating). you can see in the dxv version, that for instance on the letters of "radio" there is a noise on the letters, which isn't in the h264 version. i also tried rendering lossless and it was not there either, so we suppose it's from the dxv codec.

you can download the videos here: http://www.bildwerk.tv/resolume/
note: movement in the video starts at 00:08

Re: dxv issue

Posted: Fri Mar 02, 2012 12:53
by Joris
DXV is not a lossless codec. It does not apply temporal compression, so the reduced data size is attained by (among others) estimating the color of a pixel by looking at its neighboring pixels. This gives the difference in result you are seeing between the two clips.

So unfortunately it's not a bug. If this is the only content playing at one time, perhaps the fps when using the h264 version is high enough to get away with?

Re: dxv issue

Posted: Fri Mar 02, 2012 13:13
by cosmowe
That's exactly the reason why I yesterday have to recommend another media software to my client.
I'm so sorry resolume!

My client asked me to play a background in full HD...and they gave me two full HD clips with alpha.
They used QT Animation codec.

First I tried to play them as the clips came from the client in Animation codec.
Result: fps break down from 60 to 29 + no straight alpha option

Then I converted the clips to DXV.
Result: Great fps + straight and good looking alpha + noisy edges, little flickerpixels in the background...

ENDRESULT:
The screensize will be 16mtr. X 9mtr. .... so the audience WILL recognize the flickering and the noisy edges.
So I have to recommend another media software for this particular event!


Greetz
cosmowe

Re: dxv issue

Posted: Mon Mar 05, 2012 09:15
by edwin
Please send us one of your files so we can have a look. We have some plans on improving image quality and this could be a good test file. If you could send us a snippet of the original file we can have a look.

Re: dxv issue

Posted: Wed Mar 07, 2012 11:47
by cosmowe
Yes I will send you the files....just have to ask for permission. Please hold the line!