webzeb
15th December 2006, 04:53
Hi,
I own a Panasonic TH-42PX60E Plasma television.
The biggest image quality flaw with such [Plasma] display is posterization. Thus gradations show a lot of banding, especially in dark tones.
From my point of view posterization is barely noticeable in detailled areas, while it looks really horrible in the smoothest ones (out-of-focus backgrounds, etc.).
Nevertheless I noticed that the smoother backgrounds are in the video, the poorer they look on the Plasma. For example, movies with a 'grainy' photo show fewer indications of posterization than the others.
According to that notice I tried to play ith FFDShow filters ':
DeBand only have a small impact. Most of the banding remains, while it's difficult to keep the mildest details. However it's quite logical : most of the banding is resulting from the Plasma display work, not from the video itself.
Noise...no, I had not become crazy ! A very small amount of noise (avih algorithm, uniform noise, no pattern, 8 on brightness, 0 on chroma) seems to reduce drasticly gradations banding. (Does noise filter act like a kind of dithering ?)
Obviously it's not perfect. Adding noise (even if it's only a very small amount) makes the picture a bit grainy. Moreover, if banding is reduced, it was not took off .
But, as far as I'm concerned, it's an excellent tradeoff ! :)
So, maybe I 'discovered' something a lot of you already know.
However I'd like to persist in this way [trying to reduce Plasma posterization using filters].
So I'd like some help/advices. Did anyone already tried this ? Could I use tried an other filter ?
(I was thinking about reducing the number of reducing the number of colors in dark tones, applying a first dithering algorithm to keep correct gradations. In fact I'd like to short circuit the dithering work of the plasma itself... I'm absolutely not versed, I don't know if it's possible and if it would really improve perceived image quality. :( )
Best regards,
Fred
PS : I play HD XviD/x264, 3000~7000kbps; 720p/1080p.
I own a Panasonic TH-42PX60E Plasma television.
The biggest image quality flaw with such [Plasma] display is posterization. Thus gradations show a lot of banding, especially in dark tones.
From my point of view posterization is barely noticeable in detailled areas, while it looks really horrible in the smoothest ones (out-of-focus backgrounds, etc.).
Nevertheless I noticed that the smoother backgrounds are in the video, the poorer they look on the Plasma. For example, movies with a 'grainy' photo show fewer indications of posterization than the others.
According to that notice I tried to play ith FFDShow filters ':
DeBand only have a small impact. Most of the banding remains, while it's difficult to keep the mildest details. However it's quite logical : most of the banding is resulting from the Plasma display work, not from the video itself.
Noise...no, I had not become crazy ! A very small amount of noise (avih algorithm, uniform noise, no pattern, 8 on brightness, 0 on chroma) seems to reduce drasticly gradations banding. (Does noise filter act like a kind of dithering ?)
Obviously it's not perfect. Adding noise (even if it's only a very small amount) makes the picture a bit grainy. Moreover, if banding is reduced, it was not took off .
But, as far as I'm concerned, it's an excellent tradeoff ! :)
So, maybe I 'discovered' something a lot of you already know.
However I'd like to persist in this way [trying to reduce Plasma posterization using filters].
So I'd like some help/advices. Did anyone already tried this ? Could I use tried an other filter ?
(I was thinking about reducing the number of reducing the number of colors in dark tones, applying a first dithering algorithm to keep correct gradations. In fact I'd like to short circuit the dithering work of the plasma itself... I'm absolutely not versed, I don't know if it's possible and if it would really improve perceived image quality. :( )
Best regards,
Fred
PS : I play HD XviD/x264, 3000~7000kbps; 720p/1080p.