Video denoising based on NL-means

Implementation of a recursive version of nl-means for video denoising.

• Author : Pablo Arias pariasm@gmail.com
• Copyright : (C) 2015 IPOL Image Processing On Line http://www.ipol.im/
• Licence : GPL v3+, see GPLv3.txt

Building

Building has been tested on Ubuntu Unix 16.04.

Dependencies:

• libtiff, libpng, libjpeg

Apart from these, some scripts provided by the code use some functions of imscript. These functions need to be accesible from the shell path.

This code ships with the following 3rd party libs:

• iio
• tvl1
• argparse

Configure and compile the source code using cmake and make. For example:

$ mkdir build; cd build
$ cmake ..
$ make

Usage

After building you'll find in the build/bin/ the following files:

tvl1flow
vnlmeans
vnlm-gt.sh
vnlm-mp4.sh
psnr.sh

vnlmeans is the denoising algorithm. Run vnlmeans -h for more help. The scripts are necessary because vnlmeans only does denoising, meanining it doesn't compute the optical flow (which optional but highly recommended), add noise or compute the psnr.

vnlm-mp4.sh: call vnlm-gt.sh but receiving and output mp4 videos. Requires avconv or ffmpeg to be installed.

vnlm-gt.sh: run vnlmeans and compare the output with the ground truth.

1. adds noise (requires awgn from imscript)
2. computes optical flow (requires downsa and upsa from impscript)
3. computes the psnr of the output (requires from impscript plambda, crop, imprintf)
4. leaves all data in an output folder which can be given as a parameter (noisy frames, optical flow, denoised, and quantitative measurements in measures.txt)

Example

$ bin/vnlm-gt.sh \
		/path/to/sequence/%03d.png \
		first-frame last-frame sigma output-dir \
		"string with the params for vnlmeans"

For example:

bin/vnlm-gt.sh ~/my-seq/%03d.png 1 30 20 parkjoy2 "-p 8 -w 10 -v"

This will (first add noise) and denoise a sequence of 30 png files. It will produce the following output to stdout:

/home/user/projects/rnlmeans/build/bin/vnlmeans -i parkjoy2/n%04d.tif -o parkjoy2/%04d_b.flo -f 1 -l 30 -s 20 -d parkjoy2/d%04d.tif -p 8 -w 10 -v
parameters:
    noise  20.000000
    patch-wise mode
    patch     8
    search    10
    w_hx      17
    w_hd      -nan
    w_thx     0.05
    w_ht      27
    w_htv     27
    lambda    1
    tv_lambda 0.85

WEIGHTED_AGGREGATION ON
AGGREGATE_TRANSITION_VAR ON
loading video parkjoy2/n%04d.tif
loading flow parkjoy2/%04d_b.flo
processing frame 1
processing frame 2
processing frame 3
...
(etcera)