anti noise filter & simple resize filter

[orbit-r]

hi
i got 2 questions.
do you use the anti noise filter for dvd2svcd conversion?
i used to, but it semms to me that it`s better to not use it if the source is good (and normally dvd source is good i think)cause it sometimes produces artefacts..

what do you think about the sharpness of the new simple resize filter?
i think its ok but the bicubic is more sharpen(shurly the speed of simple resize is very good)

and this combination (no ANF,simple resize,no temporal smoother)
gives very good,and fast results..

ps:do you think in a future release of the simple resize filter there
will be more sharpness with the same speed(or is sharpeness the thing which slow down the speed like bicubic?)

what do you think?
thanxs
orbit-r

[DDogg]

I would suggest you read more about the filters. Try the avisynth forum as well as numerous threads on this subject here and in the advanced forum. Use the search feature. It works well now.

The bicubic and bilinear filters actually process the input. They make changes to the video. Simple resize only resizes which is exactly what it was designed for. Thus, it is not what SimpleResize is NOT doing, it is what bicubic IS doing.

Each filter has its own particulars. Bilinear tends to soften and blur a very small amount. This is useful on noisy source.

Bicubic, when using .0,.75, tends to give a "pop" to the video or some might say make it "hotter". Bicubic with parameters like .333,.333 (called "soft") or .0,.50 (called "neutral") affect the video differently.

Personally I compromise and if the source is clean and I have bitrate available above 1800-2000 I use .0,.60.

If bitrate is lower than 1500 I would use bilinear as it tends to be easier to compress.

Read more.

[gerti67]

Hi orbit-r,

i just want to add a little to DDogg's good explanation as i did quite a lot of testing with this new SimpleResize and the other resize methods, too.

From my experience, the sharpness with the new SimpleResize reaches its highest level when using an "Anti noise filter" of "0" and is nearly comparable with the BicubicResize of 0.00/0.60 with the exception that edges appear a little bit "rougher" and fine patterns (e.g. bushes in the background) tend to produce a little more "Moiré pattern". (You can read this in the threads DDogg already mentioned in detail.)

Why i post another reply is that you asked for the "Noise filtering" that i think was not covered yet clearly.
I found out that using the "CCE Noise filter" with the SimpleResize seems to function quite well. For example with a value of "15" for "Noise filtering" you nearly get visual results like using the BilinearResize and even the compression tends towards it. (In particular i think the SimpleResize algorithm leaves "Noise" that is "good food" for the "CCE Noise filter".)

If you want to do some testing on your own, here is what i did:
Use internal ripping with dvd2svcd and encode some little chapters with different settings (Resize methods, Filtering, ...) and name the encoded MPEGs wisely. Use WinDVD to take snapshots of always the same frames (it's quite difficult) and name them corresponding to the MPEGs (just to not get confused). Use IrfanView (the best freeware graphic viewer in my opinion) and make a slideshow with the captured scenes (i use automated 1 second picture change) then lean back, watch close and have a look at the changing pictures with the different resize and filter settings. It is better to only test 2 or 3 different pictures at a time. Look for details and you get quite a clear impression on what the different settings are doing when encoding. Find out your prefered setting and stay with it as beauty is in the eye of the beholder and no one can do this job for you.

Greetings,
gerti67

[orbit-r]

hi
thanx people now i know some more about and how the filters work(and i`m going to inform me more about this..)

did also some test like gerti said and found for me that
the bicubic at 0.00\0.60 anti noise filter at 1 without temporalsmoother seems very good..

gruss
orbit-r

[xrv1138]

gerti67
was wondering if the anti noise of 15 gives a soft result like bilinear ?
and i was also wondering what your personal preferred settings are now for a generic dvd backup ?
asking because you have done a great deal of excellent testing
(i know end results are personal taste)

[gerti67]

Hi xrv1138,

from my testing i can say that they both look nearly the same when it comes to flat areas and mainly the whole backround scenery as it is always the part of the movie that is not focused from the camera and for this reasons gets "blurred" when using "15" for noise filtering. Large areas with nearly the same colors also look as "smooth" as with the BilinearResize.

The main difference is for example with edges of persons or objects that are focused by the camera. Those edges are not as smooth as with the bilinear method but not as outstanding as with lower values for the noise filtering. Also it helps a little bit with the "Mosquito Noise" and the "Ghost Shadowing".

When watching on a TV they look pretty the same but i would prefer the simple one with 15 over the bilinear. (Remark: From my testing i found out that with higher values than 15 the effect is not increasing any more and file sizes aren't getting smaller, too. Also the speed impact on CCE nearly tends to zero when filtering with higher values, so don't be afraid of it.)

As for now i use SimpleResize with IQP: 17 and ANF:2 with 4 Pass VBR on my conversions and i'm really satisfied with it mainly for the speed as i only have a 1.2 GHz Duron. But i must admit that the best setting is perhaps BicubicResize with 0.00/0.60 with IQP:17 and ANF:2 with 4 Pass VBR as some areas in the background look slightly better. But for me the speed drop of about 20% on my system is not worth it, i think.

Greetings,
gerti67

[xrv1138]

gerti
thanks a lot :)