Best way to reduce noise from capture (like Neat Image) ???

[Morpheus_xx]

Hi,

I have some TV-capture files with quite much of noise. I already tried some de-noise filters for avisynth, but the result is not so good.

Lately I edited some images from my digi-cam with Neat Image. The result of noise-removing is really great. So is there anything else powerful filter available for videos?

See the difference yourself:
http://mf-the-one.netfirms.com/capture.htm

Thnx in advance,
Morpheus

[fellaw]

There is no "best" way to reduce noise from captures. It depends very much on your source quality and the codec used. Could you post your settings?

I don't know whether it depends, but have you tried seperating the fields(if you got any) before applying any denoise filters?

I made very good experience with DustV5.

Before: without Pixiedust (http://people.freenet.de/TC.Xan/images/ohne_DustV5.png)

After: Pixiedust applied(limit=8) (http://people.freenet.de/TC.Xan/images/mit_DustV5.png)

Here (http://www.avisynth.org/warpenterprises) you'll find more avisynth filters, if you're missing anyone.

There are also some powerful filters for Virtual Dub. As with Avisynth 2.5, you can use them with it, too. But you'll have to cope with color space conversions.

For some reason, Pixiedust doesn't help with your sample. Maybe because there's no motion, could you please post a short clip?

Edit:

This (http://www.geocities.com/wilbertdijkhof/analog_comp/comparison.htm) comparison could help you to decide which filters to use.

[Morpheus_xx]

Thanks for your answer. I will try this Dust one. The comparision of denoisers I'll watch tomorrow at work.

Currently I capture as MPEG2 with 6500kbit/s. So my 41min are usually 1.9-2.1GB in size.

Unfortunately I only have a 56k modem so I can't upload sample-clips so fast. Damn, I uploaded a 2mb clip (whole 2 sec!;) ) but my webspace denies downloads over 256kb. Didn't know this :(

[fellaw]

I'm glad I could help.

But beware, DustV5 is an avisynth 2.0 plugin!

Just include this line before you load DustV5 if you're using Avisynth 2.5x

LoadPlugin("LoadPluginEx.dll")

Edit:

Btw, which device and software are you using for capture?

[Morpheus_xx]

I have a Hauppauge WinTV with BT8?8 chipset and capture with Intervideo WinDVD Recorder 5.

I'd like to use iuVCR or something like this, but there are always problems with resolutions (for capture), codecs etc. So the WinDVD version was the easiest for me.

[DarkNite]

VirtualVCR is simple and I've used it along with my WinTV card several times when I wanted to set up scheduled captures for while I was away on business, or just busy in general.

If you want the highest quality, or to do any editing/processing/transcoding afterwards, it's best to use a lossless codec and capture to your target resolution (assuming 480x480 or greater is your target).

As for treating very noisy caps with Dust you might want to search for NoMoSnow, or iiP. Those methods take patience, but yield pleasing results with the most difficult of sources.

BTW, using a limit value of over 2 with PixieDust can harm more than help in some cases. Unless you're going for that mosaic blocking look. ;)

[Morpheus_xx]

After a short test with Virtual VCR (again), I found some problems:

- capture to HuffYuv produces to big files (I capture 2 hours)
- MPJEG from ffdshow with quality of 95 is still quite big, but with Q 85 there are artifacts
- audio was out of synch for my test, sampling rate got sth. like 48542Hz. So I can't recompress my pcm to mp3 without ssrc.
- recompression to XviD is slower than from MPEG source


so for now the WinDVD-R way with a quite high bitrate of 6500kbit and sound with exactly 48kHz is more comfortable.

For conversion I use such a avisynth script:

Mpegsource()..
Undot()
FluxSmoth(12,12)
LanczosResize3(592,432)
Sharpen(0.2)

Codec than is XviD with 1250 kbit, dual pass.

The resolution I selected because of my standalone player, so that it plays without borders and correct aspect ratio.

The thing to improve is still the noise removal...

Morpheus

[fellaw]

Regarding that noise, you should begin with the physical part of the capture. Your sample just doesn't look right to me, there are severe rainbow artifacts which don't seem to be related to the source. At least I get better quality when capturing RTL-II via satellite. It's hard to tell without a short clip(2 seconds should be enough).

Which source are you using? RF, Composite, S-Video?
What kind of material is it? cable, satellite, vhs?
Noise can also be caused by high frequency devices inside the pc, e.g. the fans or power supply.

It's best to minimize causes from above before trying to filter them via post processing.

You should consider buying a new capture card, because (at least IMHO ) BT878 cards are far worse than those based on Philips SAA7134(Cinergy 400) and the new CX2388x(Leadtek Expert).

[Inc]

Originally posted by Morpheus_xx
- capture to HuffYuv produces to big files (I capture 2 hours)
- MPJEG from ffdshow with quality of 95 is still quite big, but with Q 85 there are artifacts
- audio was out of synch for my test, sampling rate got sth. like 48542Hz. So I can't recompress my pcm to mp3 without ssrc.
- recompression to XviD is slower than from MPEG source
- Well HuffYUV is LOSLESS thats why Files do end up larger! But the quality in here is the gain!
- Dont use (IMHO) Mjpeg from ffdshow as its very slow (in my cases) ... better use PicVideo at Quality=19
- Thats due you did not set up VirtualVCR correctly as VirtualVCR gots in its audio options a "resample audio dynamically" which lets your captures end up in correct wanted fps streams IN sync.
- Yep, XVID for capturing is a) slower and btw b) a worse choice due YV12 (4:2:0) colorspace subsampling. Youll get into trouble when capturing interlaced/Telecined Material.

And ... I do agree with Fellaw, as a 7134 Card is excellent and btw not expensive. If you do live in Germany you also can buy the Typhoon PCI Capture Card from Conrad Electronics = 39.90 Euros .. and in combination with the Cinergy 1.4 driver it gives excellent results.

[E-Male]

Originally posted by DarkNite
capture to your target resolution
i'd capture to highest resolution

[Inc]

(assuming 480x480 or greater is your target)
I would even go deeper that a direct capturing out of a TV broadcasting via analogue capture to direct SVCD Resolution will end up in an AR error. (Well in case of PAL defenitely).
As an 480x480 capture resized to its PAR 1:1 state wont match NTSC TV width

Or can we just resize from 480x480 up to 640x480 without AR error?? At PAL that wont work as in case of PAL you should have to capture at 468(464)x576 which will be padded later to 480x576. IF capuring directly for SVCD purposes.

[Morpheus_xx]

Originally posted by fellaw
Which source are you using? RF, Composite, S-Video?
What kind of material is it? cable, satellite, vhs?

...
SAA7134(Cinergy 400) and the new CX2388x(Leadtek Expert).

I capture directly from cable TV. The picture does always look better when I use DScaler to show it. As soon as I capture with other programms, there seems to be a lot more noise. Could be because of overlay with DScaler that it looks better?

Yesterday I captured with VirtualVCR and will transcode it today to XviD.
@incredible: Thanks for the hint with audio synch!

But I used ffdshow-MJPEG with Q=93 and it is very fast for me.


@incredible:
I live in PAL-land ;) so I made a short try with WinDVD-Recorder and captured 480x576 MPEG2 (the SVCD profile). This test file played fine on my standalone DVD-Player (with Divx ;) )

[Morpheus_xx]

I've finished and watched (on TV) my last capture.

The quality of VirtualVCR/MJPEG is indeed better than the WinDVD-recorder version. I used Undot() and FluxSmooth() in my script.
And I can have full resolution as result (WinDVD-Rec captures 768x576 and crops to 720x576 = DVD profile).

The transcode MJPEG->XviD duration is a little longer than from mpeg-source.

This result suits my needs, thanks for your tips.