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mJPEG - Convert FITS images or mosaics into grayscale or color JPEG images


mJPEG [-d] [-t power] [-s statusfile] [-ct color-table]

[-gray in.fits minrange maxrange [logpower/gaussian]

[-red red.fits rminrange rmaxrange [rlogpower/gaussian]

[-green green.fits gminrange gmaxrange [glogpower/gaussian]

[-blue blue.fits bminrange bmaxrange [blogpower/gaussian]

-out out.jpg


Generates a JPEG image file from a FITS file (or a set of three FITS files in color). A
data range for each image can be defined, and the data can be stretched by any power of
the log() function (including zero: linear). Pseudo-color color tables can be applied in
single-image mode.

Note: If creating a true color image, all input images must have identical WCS information
(ie, same size, resolution, coordinate system, etc).


-d Print out additional debugging information

-t power
Increasing the value of power will enhance the contrast between colors; useful when
all pixels are close to white, but you wish to accentuate the color difference.

-s statusfile
Write output and errors to statusfile instead of stdout

-ct color-table
Choose a color table for pseudo-color images; color-table can be an integer between
0 and 11. Click here for samples of each color table.


mJPEG takes as arguments a list of FITS images to be used as input for the true- or
pseudo-color image. To create a pseudo-color image from a single FITS file, use the -gray
flag; to create a true-color image, use the -red, -green, and -blue flags together. The
syntax for each is the same:

-color Provide the image name and stretch information to be used for color (one of:
"gray", "red", "green", "blue")

Filename of input image for this color. Can use a specific FITS extension by
including it as: "filename.fits[X]", where X is the HDU number.

minrange maxrange
Lower/upper pixel values to use when stretching the image. Can also be expressed
as a percentage, a sigma value, or any combination of these three. Some examples:

0 100
0s 99.999%
-1s 1s

Specify a log power to use in stretching the image. Can be a positive integer or
one of:

linear (default)

-out out.jpg
Path to the output JPEG image


The output message includes stretch information from the creation of the JPEG:

Psuedo-color (gray input only):

[struct stat="OK", min=datamin, minpercent=minfrac, max=datamax, maxpercent=maxfrac]

Three-color (red/green/blue inputs):

[struct stat="OK", bmin=bdatamin, bminpercent=bminfrac, bmax=bdatamax,
bmaxpercent=bmaxfrac, gmin=gdatamin, gminpercent=gminfrac, gmax=gdatamax,
gmaxpercent=gmaxfrac, rmin=rdatamin, rminpercent=rminfrac, rmax=rdatamax,


To create a grayscale image from a FITS file:

$ mJPEG -ct 1 -gray SINGS_B.fits 0s 99.999% gaussian -out SINGS_B.jpg
[struct stat="OK", min=0.391706, minpercent=50.00, max=136.555, maxpercent=100.00]

Output grayscale JPEG:

To create a true 3-color image from three input images:

$ mJPEG -t 2 -blue SINGS_B.fits 0s 99.999% gaussian

-green SINGS_R.fits 0s 99.999% gaussian

-red SINGS_I.fits 0s 99.999% gaussian

-out SINGS_3color.jpg [struct stat="OK", bmin=0.391706, bminpercent=50.00,
bmax=136.555, bmaxpercent=100.00, gmin=2.98851, gminpercent=50.00, gmax=366.148,
gmaxpercent=100.00, rmin=4.26902, rminpercent=50.00, rmax=295.179,

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