man mrwtoppm (Commandes) - mrwtoppm
NAME
SYNOPSIS
< infile > outfile
DESCRIPTION
converts a Minolta DiMAGE 5/7/7i/7Hi/A1 RAW image read from its standard input into a PPM image which is written to its standard output.
first processes the system wide parameter file Entries in this file (if it exists) will override the compiled defaults.
then processes the user's parameter file if it exists. Entries in this file will override both compiled defaults and entries in the system wide parameter file.
then processes command line options, which if given will override compiled values and values set in the initialization files. The program will then read a mrw file from its standard input, convert it as specified, and write a PPM file to its standard output.
PROCESSING AND OPTIONS
- •
-
The pixels input from the .mrw file are color corrected.
The algorithm is to multiply the input pixels by gain values for each color.
The default color balance is "camera", which uses the color balance data
the camera stored in the mrw file.
- -wb name
- Overrides the default color balance. The following color balances are known to mrwtoppm: camera, daylight, flash, cloudy, tungsten, flourescent, none, and preset6. None does not balance the colors. The other color balances are camera specific and are obtained from data stored in the mrw file. Preset6 is a stored preset the meaning of which is currently unknown.
- -wb rgain Ns : Ns ggain Ns : Ns bgain
- Manually override color balance. Red, green and blue pixel values are multiplied by rgain Ns /256, ggain Ns /256 and bgain Ns /256 respectively.
- -cmapPath pathlist
- By default, color balances other than those listed above are searched for in the following path list: .:colormaps:$HOME/.mrwtoppm/colormaps:/usr/local/share/mrwtoppm/colormaps . This list can be changed using this option.
- •
-
The image is rotated by 0, 90, 180, or 270 degrees.
- -rotate angle
- Rotate image clockwise by angle degrees. The default is 0. The angle must be one of the above four values.
- •
-
The image can be optionally be scaled by an even factor (N).
When the image is scaled
bayer pattern interpolation is not performed and
output pixels are calculated simply by averaging the same color pixels
in N by N input blocks.
If the scale does not evenly divide the image size (that is, for scales
other than 1, 2, 4, and 8) the final image size is rounded down, and the
excess input pixels are ignored. The selected pixels are centered on the
image center. The intent is to allow high-speed image preview.
- -scale scale
- Divide image height and width each by scale . Legal values are 1 (default, no scaling), 1/N for even N.
- •
-
A dark field image, if any, is subtracted from the image data.
The dark field image must be an mrw file the same size as the image data.
It should be an image taken with the same ISO and shutter speed as the image, but with the lens covered.
The intent is subtract the CCD "noise" caused by long exposure times.
Default is none.
- -darkfield name
- The dark field image is looked for in a file in the dark field path.
- -darfieldpath pathlist
- •
-
If the image is not scaled, the Bayer pattern data is interpolated.
The following algorithms are implemented:
- •
- The vector median algorithm of Gupta and Chen (default).
- •
- A simple bilinear interpolation scheme (faster but much lower quality).
- -imethod name
- Select the interpolation method to use: bilinear, vmedian (default), mgbrb, mgmrb.
- -Lab
- Vector median interpolation and filtering is done in CIELab color space (default).
- -noLab
- Vector median interpolation and filtering is done in the camera's color space
- -vtol value
- Sets the error tolerance for the vector median algorithm (larger is faster, but lower quality). The default is fairly high quality.
- •
-
(Experimental)
A median of medians filter may be applied.
- -mfilter
- Apply median of medians filter.
- -nomfilter
- Do not apply median of medians filter (default).
- •
-
The image's tone curve is adjusted.
- -tone name
- Apply the named tone curve. Default is "minolta". The tone curve "none" is just that.
- -tcpath pathlist
- Set the tone curve search path. The default tone curve search path is .:tonecurves:$HOME/.mrwtoppm/tonecurves:/usr/local/share/mrwtoppm/tonecurves .
- •
-
An additional vector median filtering step may be performed.
- -vmf
- Apply additional vector median filter.
- -novmf
- Do not apply additional vector median filter (default)
- •
-
The image may be sharpened or blurred.
In Lab mode, the luminance and chrominance channels can be sharpened/blurred independently.
Sharpening is done by unsharp masking.
- -blur val
- Determine convolution matrix used for blurring This is a 3x3 matrix having the following values: 1 1/val 1 1/val 1/val^2 1/val 1 1/val 1
The matrix is scaled so that the matrix elements sum to 1. Larger values cause more blurring. Default is 0.5. -isharpen val Sharpen pixels by val times the difference between the original and blurred values. Negative values blur the image. An amt of -1 replaces the pixel with the blurred pixel generated above. In Lab mode, only the L channel is affected. In RGB mode, all channels are affected. Default is 2. -csharpen val In Lab mode only, sharpen/blur the two chrominance channels by val . Default is -1. The image is converted from the camera's color space into the output color space. The former defaults to the camera's color space, the latter to sRGB.
- -cprofile name
- Overrides the default camera profile.
- -oprofile name
- Overrides the default output profile.
- -profilePath pathlist
- Set the profile search path. The default tone curve search path is .:profiles:$HOME/.mrwtoppm/profiles:/usr/share/liblcms/profiles:/usr/share/mrwtoppm/profiles .
- -gamma val
- Overrides the default gamma factor to correct for. The default gamma to correct for is 1 (meaning no change).
- -contrast val
- Override the default contrast setting. The image is contrast stretched so that the val Ns /2000 largest color values and the val Ns /2000 smallest color values are output as the maximum or minimum value respectively. The default is 1. If the contrast value is 0, the color values are only scaled such that the largest value is output as the maximum value. If the contrast value is negative, no contrast stretching is done.
- -8
- Output an 8 bit/color/pixel PPM file (default).
- -16
- Output a 16 bit/color/pixel PPM file.
- -xvmini
- Output an xv thumbnail file (8 bits total per pixel: 3 red, 3 green, 2 blue). Legal thumbnail files must be no larger than 80x80. The user is responsible for selecting a suitable scale factor for achieving this.
FILES
- $HOME/.mwrtoppm/mrwtoppm.rc
- The initialization file consist of a sequence of lines. Each line sets one option. Option names are the same as the command line options, except that the leading dash is omitted. Options that take a parameter have the form option Ns = Ns value . Options that do not have a parameter have the form option Ns = (the need for the = is a bug that will get squished later).
- /usr/share/mrwtoppm/colormaps/
- Location of colormaps used for color balance correction.
- /usr/share/mrwtoppm/profiles
- Location of camera profiles used for color space conversion.
- /usr/share/mrwtoppm/tonecurves/
- Location of tone curves used for tone curve adjustment.
SEE ALSO
BUGS
Neither this program nor any others in the package take image files as parameters. They all read the image from the standard input and write their results (a PPM file in this case) to standard output. Unfortunately, this causes new users lots of grief.
AUTHOR
was written by Bradley Broom Aq dobroom@swbell.net .
This manual page was converted from Ns 's manual by Guus Sliepen Aq guus@sliepen.warande.net for the Debian GNU/Linux system.