dark and grainy video - need help

[rizdragon]

hi,
i've made a few video clips from my digital camera, Casio Exilim EX Z750 http://www.casio-intl.com/asia-mea/en/dc/past/ex_z750/
the videos are dark due to low light and thus has lots of noise.

how do i clean the videos up?

i have Virtualdub and Neatvideo. i also have tried Vreveal. but i am not satisfied with the results. i don't even know if the videos recorded are progressive or interlaced. the videos are recorded at the highest quality 640 x 480 (HQ), 4.0 Mbits/sec. (30 frames/sec.).

the videos are private and thus i can not upload a sample. i don't know i uploading another sample using the same camera and setting would help or not. all i want to do is to be able to play these videos on my pc. the videos are curently too dark and too noisy to see any substantial details... if i play with VLC player and adjust settings, the brightness and thigs are ok but the noise still bothers me. if i can get rid of some noise without loosing details by using VLC or the software i have that will be great.

thank you.

[_Al_]

It is quite old camera, video is SD resolution. It will look bad on PC screen even if there was no noise. With noise even worse. You blow it up on HD screen and it just looks bad.

I'd say video is progressive. You can use Mediainfo to know for sure.

You can always point at your floor or better some furniture with your camera in low light to get some noise that you usually get and upload it.

[jagabo]

Or, even in the sensitive video, there's probably some short section that contains nothing personally identifiable.

But try this in a recent (last few years) version of VirtualDub: First add the Brightness/Contrast filter. Move the brightness slider up by one tick mark. It is important to do this first because this filter works in YUV, before any super-darks have been lost due to RGB conversion. Then add the levels filter and try adjusting levels with the preview window open. Use "Sample Frame" to get an idea of the luma range in the video. Don't forget about the gamma slider to help bring out dark details. Using RGB mode instead of luma mode will help retain colors (although you can bring colors out later with a saturation bump).

[sanlyn]

the videos are recorded at the highest quality 640 x 480 (HQ), 4.0 Mbits/sec. (30 frames/sec.).

A bitrate of 4000 is not "highest quality" for 640x480 full-frame video. It is, in fact, a little on the low side, even for DV. Underexposure and low light conditions with consumer cameras is dreadful. It consists mostly of noise. EVen if you pull some detail out of the darkness, you'll see that the word "detail" is a misnomer: what's there is a lack of data that can define any "detail" worth recovering. Such a video has to be repaired, if possible, in its original YUV colorspace. Once crushed and distorted detail is converted to RGB in VirtualDub, the problem is made worse. Usually some form of contrast masking and other techniques are used in YUV to try to repair such clips.

the videos are private and thus i can not upload a sample.

We cannot advise without a sample of the video to work with. Another video sample with similar problems from the same camera would be more conclusive.

if i play with VLC player and adjust settings, the brightness and thigs are ok but the noise still bothers me. if i can get rid of some noise without loosing details by using VLC or the software i have that will be great.

The typical "brightness " control will not help the problem, whether it's in a player or a filter.

[poisondeathray]

the videos are recorded at the highest quality 640 x 480 (HQ), 4.0 Mbits/sec. (30 frames/sec.).

A bitrate of 4000 is not "highest quality" for 640x480 full-frame video.

The OP probably means that's the highest quality mode available for that particular camera model

[sanlyn]

I took a look at the camera manual (not easy to get to). You're probably right.

[Djard]

I've had good success with XMedia Recode for quick edit of brightness and contrast in video clips. The preview window shows the results immediately; and other features, like the image stabilizer work nicely too, if you need it. For best results, I recommend adding a little more contrast than brightness--e.g. +10% brightness and +14% contrast, and set Gamma at about -7 for clarity. Higher settings than these have not worked well for me.

If you add sharpness, limit it to 22% as artifact becomes quite noticable after that. I haven't tried the noise filter, which is probably the thing you want mostly. When recoding, you already know that increasing the bitrate will not add quality; in fact, if planning to view your videos on a computer only, you might consider a much lower bitrate as the difference in quality is negligible. Well, so methinks.

I discovered that you CAN significantly improve the video quality by decompressing the file. I once decompressed an MP4 file. The decompressd file was huge, but the video quality was dramatically better.

[rizdragon]

Thank you guys for your suggestions... but like i said i am a newbie... and don't know much... so the suggestions you have given have flown over my head... i can upload a sample, not of the original videos, but by taking a video in similar lighting conditions. but first i'll have to find that old camera of mine... i know you guys can't help much without a sample but consider it this way... the light in the room is from a single 60 watts tungstun light blub which is at the other end of the room. i've since then moved to a new house so won't be able to replicate the exact same conditions and will have to find where i've kept the camera.
if anyone can guide me, step by step... as i have virtuadub but hardly know how to use it, and other video editing/enhancing software. when i use vreveal and set things to autocorrect, they improve but i still see lots of grains and dots/specks moving around... i need to eliminate those. they are there coz of low light.
thank you all for your replies and help. i really wish it was easier to clean up the videos. i have them in their original format in which they were recorded in AVI.
Thank you once again for your help. i'll try posting a sample by the end of the week...

[rizdragon]

and guys, can you suggest any good digital camera or digital video recorder to record in low light conditions (optical zoom not more than 3x to 5x required) which in in the low to medium budget range, like US$ 100 to US$150. but if the difference is substantial, i might increase the budget size.

thank you.

[_Al_]

You need to denoise your footage. So you need denoise filter. You work in VirtualDub so you need some free Virtual Dub's denoise filter. You download something from web. MSU denoise filter is free for example. You can try it and use some default settings, but filters usually have some settings to tune things up. MSU denoise filter: http://compression.ru/video/denoising/index_en.html . You download vdf file and put that in VirtualDub's plugin folder. Then this filter will show up in the filter menu window . Then you apply it to video in VirtualDub: Video/Filters/add ...

Notice there is all kinds of denoise filters, always working a bit differently, ...

Denoise belongs to category where someone has to see the footage to recommend and try particular filter or combination of filters that will work best for particular video otherwise it is a shot in the dark. You'd use brightness, contrasts and other maybe.

[jagabo]

You need to denoise your footage.

Getting a camera that works better in low light will be far better than denoising video from a camera that performs poorly in low light. Unfortunately, good low light performance requires big glass. Big glass requires a big sensor. A big sensor means high resolution and powerful electronics to deal with. Along with that usually comes a big body and a big price.

[_Al_]

I think the same, top consumer camcorders from Sony, Panasonic, Canon is the best compromise to deal with noise and picture quality. Decent DSLR's too.