Quantcast KDVD: Why this Artifact? - digitalFAQ.com Forums [Archives]
  #1  
09-20-2005, 07:14 AM
Prodater64 Prodater64 is offline
Free Member
 
Join Date: Mar 2003
Location: Palma de Mallorca - España
Posts: 2,925
Thanks: 0
Thanked 0 Times in 0 Posts
How call you it?
What is the reason?



HC Encoder.
Present in 2pVBR and CQ_Maxbitrate modes.
Doesn't matter if LRemoveDust_YV12 or Removegrain + Deen used, it is present anyway.
Reply With Quote
Someday, 12:01 PM
admin's Avatar
Site Staff / Ad Manager
 
Join Date: Dec 2002
Posts: 42
Thanks: ∞
Thanked 42 Times in 42 Posts
  #2  
09-20-2005, 07:50 AM
Dialhot Dialhot is offline
Free Member
 
Join Date: May 2003
Posts: 10,463
Thanks: 0
Thanked 0 Times in 0 Posts
How did you take your snapshot ?
Because I often have this kind of things but this is a player problem. The artifact is not in the video.
Reply With Quote
  #3  
09-20-2005, 11:07 AM
GFR GFR is offline
Free Member
 
Join Date: May 2002
Posts: 438
Thanks: 0
Thanked 0 Times in 0 Posts
You mean the ringing next to the sharp transition to the black borders? That's Gibbs or ringing.

Does the original show some ringing?

Does it happen without any filtering, or with other encoders?

Are the black borders part of the picture or are they introduced by the player?

If they are part of the picture and the ringing is induced by filtering, make sure you are filtering before adding the borders.

If the ringing is a product of the encoding you need to have less quantization in the high frequencies (try a different matrix or different settings.

Make sure you crop at an integer number of blocks.

Hope it helps.
Reply With Quote
  #4  
09-20-2005, 11:58 AM
Boulder Boulder is offline
Free Member
 
Join Date: Sep 2002
Location: Lahti, Finland
Posts: 1,652
Thanks: 0
Thanked 0 Times in 0 Posts
You can often see that where the film pixels end and borders begin. Usually the borders are not mod-16 in size so a macroblock contains a sharp edge between the black and non-black material. That's why that ringing occurs.
Reply With Quote
  #5  
09-20-2005, 01:51 PM
Prodater64 Prodater64 is offline
Free Member
 
Join Date: Mar 2003
Location: Palma de Mallorca - España
Posts: 2,925
Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by GFR
...
Does the original show some ringing?
Yes, the original show same artifact.
Reply With Quote
  #6  
09-20-2005, 02:20 PM
GFR GFR is offline
Free Member
 
Join Date: May 2002
Posts: 438
Thanks: 0
Thanked 0 Times in 0 Posts
GIGO = garbage in garbage out If the source is bad, there's a natural tendency that it gets worse. It's a law of nature.

Try cropping out the artifact (at the next block boundary), or using some kind of deringing filter (you may find it difficult to get good deringing - YMMV).
Reply With Quote
  #7  
09-20-2005, 03:03 PM
Boulder Boulder is offline
Free Member
 
Join Date: Sep 2002
Location: Lahti, Finland
Posts: 1,652
Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by GFR
or using some kind of deringing filter (you may find it difficult to get good deringing - YMMV).
And in this case, deringing should be applied only to the areas that are close to the borders. IMHO it's much better to crop a few more pixels off than blur the whole image with deringing - which will never remove the problem completely without destroying all the details elsewhere.
Reply With Quote
Reply




Similar Threads
Thread Thread Starter Forum Replies Last Post
KDVD: Vmesquita's K(S)VCD/KDVD Calc 1.1 released! vmesquita Video Encoding and Conversion 21 02-15-2007 08:39 AM
KDVD: TMPGEnc template/Parameters for 352x240 Mpeg2 KDVD rab Video Encoding and Conversion 3 12-31-2006 02:12 PM
KDVD: XViD TV Episodes to KDVD Guide Dassin Video Encoding and Conversion 24 06-28-2006 11:29 AM
KDVD Expres?? KDVD?? Docking Gate???!!! PRADER Convertir y Codificar Video (Español) 20 11-03-2004 08:02 PM
KDVD continua ficando azul (divx ---DIKO--> KDVD) el34 Conversão e Codificação de Vídeo (Português) 5 07-27-2004 07:36 AM

Thread Tools



 
All times are GMT -5. The time now is 04:33 AM  —  vBulletin © Jelsoft Enterprises Ltd