dcraw

Section: User Commands (1)
Updated: May 21, 2006
Index Return to Main Contents
 

NAME

dcraw - command-line decoder for raw digital photos  

SYNOPSIS

dcraw [OPTION]... [FILE]...  

DESCRIPTION

dcraw decodes raw photos, displays metadata, and extracts thumbnails.  

OPTIONS

-v
Print verbose messages, not just warnings and errors.
-c
Write decoded images or thumbnails to standard output.
-e
Extract the camera-generated thumbnail, not the raw image. You'll get either a JPEG or a PPM file, depending on the camera.
-z
Change the access and modification times of an AVI, JPEG or raw file to when the photo was taken, assuming that the camera clock was set to Universal Time.
-i
Identify files but don't decode them. Exit status is 0 if dcraw can decode the last file, 1 if it can't. -i -v shows metadata.
dcraw cannot decode JPEG files!!
-d
Show the raw data as a grayscale image with no interpolation. Good for photographing black-and-white documents.
-D
Same as -d, but totally raw (no color scaling).
-h
Output a half-size color image. Twice as fast as -q 0.
-q 0
Use high-speed, low-quality bilinear interpolation.
-q 2
Use Variable Number of Gradients (VNG) interpolation.
-q 3
Use Adaptive Homogeneity-Directed (AHD) interpolation.
-f
Interpolate RGB as four colors. Use this if the output shows false 2x2 meshes with VNG or mazes with AHD.
-B sigma_domain sigma_range
Use a bilateral filter to smooth noise while preserving edges. sigma_domain is in units of pixels, while sigma_range is in units of CIELab colorspace. Try -B 2 4 to start.
-b brightness
By default, dcraw writes 8-bit PGM/PPM/PAM with a BT.709 gamma curve and a 99th-percentile white point. If the result is too light or too dark, -b lets you adjust it. Default is 1.0.
-4
Write 16-bit linear pseudo-PGM/PPM/PAM with no gamma curve, no white point, and no -b option.
-3
Same output as -4, written in Adobe PhotoShop format.
-k black
Set the black point. Default depends on the camera.
-a
Automatic color balance. The default is to use a fixed color balance based on a white card photographed in sunlight.
-w
Use the color balance specified by the camera. If this can't be found, print a warning and revert to the default.
-r mul0 mul1 mul2 mul3
Specify your own raw color balance. These multipliers can be cut and pasted from the output of dcraw -v.
-n
Same as -H 1.
-H 0
Clip all highlights to solid white (default).
-H 1
Leave highlights unclipped in various shades of pink.
-H 2-9
Reconstruct highlights. Low numbers favor whites; high numbers favor colors. Try -H 5 as a compromise. If that's not good enough, do -H 9, cut out the non-white highlights, and paste them into an image generated with -H 3.
-m
Same as -o 0.
-o [0-5]
Select the output colorspace when the -p option is not used:

0   Raw color (unique to each camera)
1   sRGB D65 (default)
2   Adobe 1998 D65
3   Wide Gamut D65
4   Kodak ProPhoto D65
5   XYZ

-p camera.icm [ -o output.icm ]
Use ICC profiles to define the camera's raw colorspace and the desired output colorspace (sRGB by default).
-p embed
Use the ICC profile embedded in the raw photo.
-t [0-7,90,180,270]
Flip the output image. By default, dcraw applies the flip specified by the camera. -t 0 disables all flipping.
-j
For Fuji Super CCD cameras, show the image tilted 45 degrees, so that each output pixel corresponds to one raw pixel.
-s
For Fuji Super CCD SR cameras, use the secondary sensors, in effect underexposing the image by four stops to reveal detail in the highlights.
For all other cameras, -j and -s are silently ignored.
 

SEE ALSO

pgm(5), ppm(5), pam(5), pnmgamma(1), pnmtotiff(1), pnmtopng(1), gphoto2(1), cjpeg(1), djpeg(1)  

BUGS

The author stubbornly refuses to add more output formats. Don't expect dcraw to produce the same images as software provided by the camera vendor. Often dcraw yields better results!  

AUTHOR

Written by David Coffin, dcoffin a cybercom o net


 

Index

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
SEE ALSO
BUGS
AUTHOR

linux.jgfs.net manual pages