NAME
yuvmedianfilter - A filter for yuv images produced by
the mjpeg tools
SYNOPSIS
yuvmedianfilter [-r num]
[-R num] [-t num] [-T
num] [-I num] [-f] [-w
num] [-s num] [-v num]
[-h]
DESCRIPTION
yuvmedianfilter is designed to
enhance/filter images. It takes the input from STDIN and writes
output to STDOUT.
This filter looks around the current point for a radius and
averages the values that fall inside a threshold. So the image is
softened and the edges become more sharp. If the input material is
noisy (it is always noisy but you do not always see it) the output
images are improved and the encoder spends less bandwidth encoding
noise. The more sophisticated version of image filtering is
yuvdenoise. But you can use both programs in the encoding procces.
It cannot process a recorded file and write the improved version to
another file.
OPTIONS
yuvmedianfilter accepts the following
options:
- -r num
- Radius for luma median (default: 2 pixels)
- -R num
- Radius for chroma median (default: 2 pixels)
- -t num
- Trigger threshold for luma (default: 2 [0=disable])
- -T num
- Trigger threshold for chroma (default: 2 [0=disable])
- -I num
- Interlacing type (0=no, 1=yes, default: taken from yuv stream)
- -f
- Fast mode, i.e. the threshold is ignored, and a simple mean of
the surrounding values is calculated.
- -w num
- In fast mode, the weight given to the current value versus the
surrounding values. Default is 8.
Note that certain combinations of radii and weights have been
optimized to be even faster -- radius 1 and weight 2.667, radius 1
and weight 8, and radius 2 and weight 8.
- -c num
- In slow mode, more than this fraction of the pixels must be
within the threshold; otherwise the pixel is simply the weighted
mean of pixels within a radius of 1. Default is 0.33333.
- -s num
- Number of beginning frames to skip. The first num frames are
written to stdout unfiltered. This is useful for resuming an
interrupted job without having to duplicate work.
- -v num
- Verbosity level (0, 1 or 2)
- -h
- Print out a help message
BUGS
It is slow. Using a radius greater than the default of
2 is painfully slow.
AUTHOR
This man page was written by Bernhard
Praschinger.
The yuvmedianfilter program was written by Mike Bernson, and
adapted to the yuv4mpeg2 stream header format by Steven M. Schultz.
If you have questions, remarks, problems or you just want to
contact the developers, the main mailing list for the MJPEG-tools
is:
- For more info, see our website at
-
SEE ALSO
mjpegtools(1),
jpeg2yuv(1),
lav2yuv(1),
mpeg2enc(1),
ppmtoy4m(1),
yuv2lav(1),
yuvdenoise(1),
yuvscaler(1)