Removing/toning down digital noise/grain on HD video source.

[Killer3737]

Hi guys,

I've got a video which is a very high quality, Digital HD video source (not film) that has in my opinion a high amount of grain/digital noise. It's visibility varies depending on the shot and it's much more obvious in stills than motion but It's still a bit annoying considering the source itself is very high quality (50Mbps MPEG2 1080i). I'm not sure it would be a factor but it's also 4:2:2 Chroma.

I'm planning two conversions, one to a H.264 high bitrate Blu-Ray and a standard-def DVD and was wondering if there is anything I could do to reduce the grain on them a bit without losing too much detail due to it.

Here is a screenshot which shows it probably at it's worst: http://www.megaupload.com/?d=68EKRO9P

I could provide a video sample if required but at 50Mbps it's going to be very big for even a short part of course.

[Killer3737]

Any help? The resoltuion downscale to DVD meant a degrain wasn't really needed there but the blu-ray would obviously stay at 1080i and still be noticable. Anything I can do or is it not worth it? Secondly since I'm re-encoding to a 38Mbps H.264 file for Blu-Ray would it also be worth deinterlacing the file or should I just leave it at 1080i?

[Killer3737]

Sorry for the bumping, but I'd really like some advice on this.

[aedipuss]

wrong colorspace maybe?

[Killer3737]

Thanks for the response but I don't know what that graph is showing and what you mean by wrong colorspace, and how that would be related to the grain? Mediainfo reports it to be YUV and 4:2:2 chroma.

[poisondeathray]

use a degraining/denoising filter before you encode

use a motion compensated one to minimize detail loss

[aedipuss]

color level should be in the 0 - 100 range. yours goes below zero and above 100. using Computer RGB to Studio RGB correction i came up with this.


[Attachment 7933 - Click to enlarge]

which results in waveform like this with gamma reduction applied to get the black more distributed.

[Killer3737]

Ok thanks for the explanation, how would I go about that correction on the video itself though?

[edDV]

Ok thanks for the explanation, how would I go about that correction on the video itself though?

Is this an uncorrected camera original or an edit master file?

It could be just a levels issue but I suspect the levels were stretched when you made that png.

Do you see the noise through the whole file or is it one particular camera shot? The png frame was typical for underexposure. It also looks more compressed than 50 Mbps.

You fix it by applying filters to the clips that need it. Usually in an edit program.

[Killer3737]

Ok thanks for the explanation, how would I go about that correction on the video itself though?

Is this an uncorrected camera original or an edit master file?

It could be just a levels issue but I suspect the levels were stretched when you made that png.

Do you see the noise through the whole file or is it one particular camera shot? The png frame was typical for underexposure. It also looks more compressed than 50 Mbps.

You fix it by applying filters to the clips that need it. Usually in an edit program.

The screenshot was saved directly from DGIndex, which I believe copies it purely?

This video is a capture of a live satellite stream, captured in it's raw format, so it is what it is. The grain depends more on the shot than the camera, the darker the colors it is the more the grain is noticeable. I also don't believe it's genuinely 50Mbps, but as I say that is how it was captured live so that is what they were streaming it at. I've seen 36Mbps streams which look comparable/better though.

I've uploaded a very short sample (89MB) here if anyone would be so kind to take a look and see what you think. I've not done anything to it, just cut out and demuxed from the original file with DGIndex.

Regarding fixing it I know I obviously need to apply some sort of filter and I assume via AVISynth, but which ones?

[edDV]

Ok thanks for the explanation, how would I go about that correction on the video itself though?

Is this an uncorrected camera original or an edit master file?

It could be just a levels issue but I suspect the levels were stretched when you made that png.

Do you see the noise through the whole file or is it one particular camera shot? The png frame was typical for underexposure. It also looks more compressed than 50 Mbps.

You fix it by applying filters to the clips that need it. Usually in an edit program.

The screenshot was saved directly from DGIndex, which I believe copies it purely?

This video is a capture of a live satellite stream, captured in it's raw format, so it is what it is. The grain depends more on the shot than the camera, the darker the colors it is the more the grain is noticeable. I also don't believe it's genuinely 50Mbps, but as I say that is how it was captured live so that is what they were streaming it at. I've seen 36Mbps streams which look comparable/better though.

I've uploaded a very short sample (89MB) here if anyone would be so kind to take a look and see what you think. I've not done anything to it, just cut out and demuxed from the original file with DGIndex.

Regarding fixing it I know I obviously need to apply some sort of filter and I assume via AVISynth, but which ones?

A full sat transponder would be 36 Mbps but rarely does one feed use a full transponder. If this was a commercial DBS download service the rate would be more like 10-19 Mbps and VBR compressed. You only get 50 Mbps off a top line pro camcorder. If somehow you capped a major live network sat feed off the live switcher, it may be about 36 Mbps if they paid for a full transponder..

[Killer3737]

It's the original live stream sent from the venue to the broadcaster as far as I know.

[aedipuss]

the filter i used is in vegas pro. it could be applied to the entire video. i'll take look at the sample stream.

[aedipuss]

'tis about 50mbps.


Complete name : C:\Users\dad\Videos\vcdhelp\sample.m2v
Format : MPEG Video
Format version : Version 2
File size : 88.9 MiB
Duration : 14s 400ms
Overall bit rate : 51.8 Mbps

Video
Format : MPEG Video
Format version : Version 2
Format profile : 4:2:2@High
Format settings, BVOP : Yes
Format settings, Matrix : Custom
Format settings, GOP : M=3, N=12
Duration : 14s 400ms
Bit rate mode : Variable
Bit rate : 49.7 Mbps
Maximum bit rate : 90.0 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 25.000 fps
Color space : YUV
Chroma subsampling : 4:2:2
Bit depth : 8 bits
Scan type : Interlaced
Scan order : Top Field First
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.959
Stream size : 85.4 MiB (96%)

[aedipuss]

my god that's some nice video. nothing at all wrong with it. it's whatever you are using to edit with. vegas pro 10 barfed and couldn't handle it, but premiere pro 5.5 does. appears to be from XDCAM HD422 cams.

here's a screenshot from pp. and i checked all the levels and all appears correct in the video.

[Killer3737]

Very trange that I am seeing more grain. Could it be something to do with the 4:2:2, the programs I'm using aren't displaying it properly? Like I say that first screenshot I provided was directly saved from DGIndex but watching the video in VLC it looks the same. I should get around to watching it on my HDTV, see what that looks like.

[aedipuss]

xdcam hd422 is a fairly rare pro cam ~ start around 20k. the sony mpeghd422 codec may not be on your system, so nothing can use the video correctly.

[Killer3737]

Oh ok, not much point me trying to do anything with it then? I loaded the clip into Premiere Pro just like you and saved a screenshot of that same exact frame and my image looks different. His face is more pink and the background more red hinted than the blacks/greys in yours.

[aedipuss]

did you choose xdcam hd422 for the project settings? it should work if you have a recent p.p. mine's 5.5 but i think 5 should work maybe 4 also.

[Killer3737]

did you choose xdcam hd422 for the project settings? it should work if you have a recent p.p. mine's 5.5 but i think 5 should work maybe 4 also.

I did, yes. I've got v5 of the suite, I'd never installed Premiere before yesterday though.

[edDV]

did you choose xdcam hd422 for the project settings? it should work if you have a recent p.p. mine's 5.5 but i think 5 should work maybe 4 also.

Explain to me where you are seeing the file?

If the OP captured this from a sat download, why would it be a camera original XDCAM file? I'm lost here.

Maybe it wasn't a broadcast but a file transfer by sat?

These camcorders use dual layer Blu-Ray carts.
http://pro.sony.com/bbsccms/assets/files/micro/xdcam/brochures/XDCAM_HD422_Family_V-2408-A.pdf

[aedipuss]

unless something drastic happened between v5 and v5.5 they should both handle it. i didn't install anything special to make it work here.

[aedipuss]

did you choose xdcam hd422 for the project settings? it should work if you have a recent p.p. mine's 5.5 but i think 5 should work maybe 4 also.

Explain to me where you are seeing the file?

If the OP captured this from a sat download, why would it be a camera original XDCAM file? I'm lost here.

he said -

It's the original live stream sent from the venue to the broadcaster as far as I know.

it's not a normal sat capture - look at the mediainfo i posted. download the sample and check it out, it's not piss poor broadcast sat quality.