UFRaw - Convert camera RAW images to standard image files.
- ufraw [OPTIONS] <rawfile(s)>
- ufraw-batch [OPTIONS] <rawfile(s)>
The Unidentified Flying Raw (UFRaw) is a utility to read and manipulate raw
images from digital cameras. It reads raw images using Dave Coffin's raw
conversion utility - DCRaw. UFRaw supports basic color management using Little
CMS, allowing the user to apply color profiles. For Nikon users UFRaw has the
advantage that it can read the camera's tone curves. Even if you don't own a
Nikon, you can still apply a Nikon curve to your images.
By default 'ufraw' displays a preview window for each raw image allowing the
user to tweak the image parameters before saving. If no raw images are given
at the command line, UFRaw will display a file chooser dialog. To process the
images with no questions asked (and no preview) use the command 'ufraw-batch'.
The input files can be either raw images or UFRaw ID-files. ID-files contain a
raw image filename and the parameters for handling the image.
UFRaw can also work as a GIMP plug-in. To activate it simply open a raw image or
a UFRaw ID-file in the GIMP.
The options supplied on the command-line decide the starting-values for the GUI.
The GUI will then allow you to tweak these values before saving the final
- Display the version of UFRaw and exit.
- Display a brief description of how to use UFRaw and
- Force window to be maximized.
- Do not display any messages during conversion. This option
is only valid with 'ufraw-batch'.
- Load all parameters from an ID-file. This feature can be
used to tweak the parameters for one file using the GUI and using those
parameters as the starting point for other images as well.
Image Manipulation Options¶
These command-line options override settings from the default configuration of
UFRaw and from any loaded ID-file. The best way to learn about how these
parameters work is to experiment with the GUI. All parameters correspond
exactly to a setting available in the GUI. Not all parameters in the GUI have
corresponding command-line options.
- White balance setting. "camera" means that UFRaw
tries to read the color-temperature and green color component that the
camera recorded in the meta-information in the raw-file. This does not
work for all cameras. If UFRaw fails to read the white-balance information
from the meta-information, it falls back to "auto".
"auto" means that UFRaw calculates the color-temperature and green
color component automatically from the image data.
The white-balance can also be set manually with the --temperature and
- Manually set the color temperature in Kelvin.
- Green color component. Range 0.20 to 2.50.
- Gamma adjustment of the base curve. Range 0.10 to 1.00.
- Linearity of the base curve. Range 0.00 to 1.00. Default
- Auto exposure or exposure correction in EV. Range -3.00 to
3.00. Default 0.
- Control how highlights are restored when applying negative
EV. 'clip' restores nothing and is therefore safe from any artifacts.
'lch' restores in LCH space, resulting in restored highlights with soft
details (good for clouds). 'hsv' restores in HSV space, resulting in
restored highlights with sharp details. The default is 'lch'.
- Control how highlights are clipped when applying positive
EV. 'digital' corresponds to using a linear response, emulating the harsh
behaviour of the digital sensor. 'film' emulate the soft film response.
The default is 'digital'.
- Adjust the color saturation. Range 0.00 to 8.00. Default
1.0, use 0 for black & white output.
- Wavelet denoising threshold (default 0.0).
- Sensitivity for detecting and shaving hot pixels (default
- Type of tone curve to use. The base curve is a combination
of the gamma curve corrected by the curve specified here. The base curve
is applied to each channel of the raw data after the white balance and
color matrix, but before the ICC transformation.
"manual" means that a manual tone curve is used. This is probably
not very useful as a command-line option, since there is no way to specify
what the curve should look like.
"linear" means that no tone curve corrections is performed.
"custom" means that UFRaw shall use the curve supplied by the
camera in the meta-information in the raw-file.
"camera" means that UFRaw shall use the "custom" curve
only if the camera was set to use it (according to the meta-information).
Otherwise the "linear" curve is used.
CURVE can be the filename (without path) of any curve that was previously
loaded in the GUI.
The default is "camera" if such a curve exists, linear
- Load the base curve from a file. The curve file format can
be either UFRaw's XML format or Nikon's NTC/NCV format.
- Type of luminosity curve to use. This curve is applied in
HSV space and therefore hue and saturation should not be effected by it.
"manual" means that a manual luminosity curve is used. This is
probably not very useful as a command-line option, since there is no way
to specify what the curve should look like.
"linear" means that no luminosity correction is performed.
CURVE can be the filename (without path) of any curve that was previously
loaded in the GUI.
The default is "linear".
- Load the luminosity curve from a file. The curve file
format can be either UFRaw's XML format or Nikon's NTC/NCV format.
- Black-point value. Range 0.0 to 1.0, default 0.0.
- Interpolation algorithm to use when converting from the
color filter array to normal RGB values. AHD (Adaptive Homogeneity
Directed) interpolation is the best, but also the slowest. VNG (Variable
Number Gradients) is second best and a bit faster. Bilinear is the
simplest yet fastest interpolation.
"four-color" is a variation of the VNG interpolation that should
only be used if you see strange square patterns in the VNG interpolation,
AHD is the default interpolation. AHD interpolation is not supported for
cameras with four color filters, such as the Sony-828 RGBE filter. In such
cases, VNG interpolation will be used instead.
- Apply color smoothing.
- Grayscale conversion algorithm to use (default none).
- Grayscale mixer values to use (default 1,1,1).
- Use FILE for raw darkframe subtraction.
The options which are related to the final output are:
- Shrink the image by FACTOR (default 1).
- Downsize max(height,width) to SIZE.
- Rotate image to camera's setting, by ANGLE degrees
clockwise, or do not rotate the image (default camera)
- Crop the output to the given pixel range, relative to the
raw image after rotation but before any scaling.
- Crop the output automatically.
- --aspect-ratio X:Y
- Set crop area aspect ratio.
- Do not apply lens correction or try to apply correction by
auto-detecting the lens (default auto).
- Output file-format to use. The default output file-format
- Output bit depth per channel. ppm, tiff, png and fits
output formats can uses either 8 bits or 16 bits to encode each of the
Red, Green and Blue components of each pixel. The jpeg format only allows
for 8 bits for each color component.
The raw-files contain more than eight bits of information for each color
component. This means that by using an eight bit format, you are actually
discarding some of the information supplied by the camera. This is not a
problem if you only plan to view the image on screen. For prints you
should consider a 16 bits workflow.
- JPEG quality factor. Range 0-100 with a higher number
giving a higher quality at the cost of a larger file. Default 85. The
--compression parameter is only relevant if the output file-format is
- Embed exif in output. Default embed exif. Exif is currently
embedded in JPEG, PNG and TIFF output.
- Enable [disable] TIFF zip compression. The zip-compression
is loss-less. Default nozip. The --zip parameter is only relevant if the
output file-format if tiff8 or tiff16.
- PATH for output file. In batch mode by default,
output-files are placed in the same directory as the input-files. In
interactive mode UFRaw tries to ''guess'' if you have a favorite output
- Output file name to use. This is only relevant if a single
raw-file is supplied on the command-line. . Use '-' to output to stdout.
The default is to name the output-file the same as the input-file but with
the extension given by the output file-format.
- Overwrite existing files without asking. Default is to ask
before deleting an existing file.
- Control whether UFRaw ID files are created for the output
image. (Default is no).
- Extract the preview image embedded in the raw file instead
of converting the raw image. This option is only valid with
Conversion Setting Priority¶
Conversion settings are applied in the following priority order:
- 1. Command-line options
- 2. Settings from the configuration file specified with
--conf=<ID-file> (ignoring any filenames in the ID-file).
- 3. Settings from an ID-file supplied as an input-file.
- 4. Settings from $HOME/.ufrawrc
- 5. UFRaw's default settings.
This means that an option supplied on the command-line always takes precedence
over all other options.
The conversion settings can be changed in the GUI before the resulting image is
$HOME/.ufrawrc or $HOME/.config/ufrawrc (depending on the system) - UFRaw
resource file containing the user default settings. This is an XML file that
can be modified with any text editor. Still, it is recommended not to edit
this file. This file is updated from the GUI when you save an image, or when
you explicitly ask to save this file in the 'Options' menu.
$HOME/.ufraw-gtkrc - An optional file for setting up a specific GTK theme for
- UFRaw homepage: <http://ufraw.sourceforge.net>
- DCRaw homepage:
- The GIMP homepage: <http://www.gimp.org>