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We would like to send a video (sequence of images), we have limit bandwidth. If there is a lot of noise, the required bandwidth (bitrate) is needed to send the video+noise becomes high that is not suitable. We have just a noisy file (i.e. we do not have noise separately). The solution is to model the noise. we do not have any other information rather than a noisy video. How we can reduce the noise? How we can model the noise?

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  • $\begingroup$ Can you add some more description (screenshot) to see what type of noise it is really? Can you tell us what is the source of noise? Is this due to poor capture, loss due to analog transmission or MPEG packet drop? is this grainy, blurry what is it? $\endgroup$ – Dipan Mehta Jun 13 '15 at 8:27
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Usualy, when you send a video over a network, the video is compressed. For instance, let's say your video is compressed using a wavelet transform. The most simple way to compress your video is to truncate the wavelet transform 's coefficients. Apply a wavelet transform on your noisy video, if your noise isn't a simple white noise, it will have a specific template. Then you can use this template to tune your initial wavelet transform 's truncation.

Strictly speaking about noise modeling, without going for any transform, you could also take all your noisy video, and build the noise's pdf in the grey level scale (one dimension histogram). If your space is RGB (3 dimension histogram), you'll prefer to use a kernel density estimator. You could also take some spatio-temporal patches say 5 temporal frame, and 50*50 spatial patches, you'll have a lot of patch with your video, treat them as realization of a random vector, so consider them as a vector of length 5*50*50, you can now calculate you noise covariance matrix, which is another modelisation. It will allow you to go for denoising/compressing with PCA.

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  • $\begingroup$ Have you tried this technique yourself? Are there any references you can add for users to learn more about this? $\endgroup$ – Dipan Mehta Jul 15 '15 at 4:13
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Reduction of Noise in a video depends on what type of noise is present in the video. The noise can be reduced by filters which are all present [There are software for this] and many type of filters such as median ,mean,wiener filter. And The noise model can be build to add noise to the video there are many matlab code as well as software also there. Gaussian ,salt and pepper,poisson and speckle noise model can be build and by adding the image sequence with the video you will get a noisy video.

imnoise(video,noisename);

this will give noisy video as output.

If you have any doubt ask me.

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  • $\begingroup$ +1 for "Reduction of Noise in a video depends on what type of noise is present" $\endgroup$ – Dipan Mehta Jul 15 '15 at 4:18

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