dcraw - convert raw digital photos to PPM format
dcraw [OPTION]... [FILE]...
dcraw converts a list of raw digital camera files to ppm(5) format.
Dozens of cameras are supported, and new ones are added as they reach
-i Identify files but don’t decode them. Exit status is 0 if dcraw
can decode the last file, 1 if it can’t.
-c Write binary image data to standard output. By default, dcraw
creates files with a ".ppm" extension.
-v Print verbose messages. Default is to print only warnings and
-d Show the raw data as a grayscale image with no interpolation.
Good for photographing black-and-white documents.
-q Use simple bilinear interpolation for quick results. The
default is to use a slow, high-quality adaptive algorithm.
-h Half-size the output image. Instead of interpolating, reduce
each 2x2 block of sensors to one pixel. Much faster than -q.
-f Interpolate RGB as four colors. This causes a slight loss of
detail, so use -f only if you see false 2x2 mesh patterns in
-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, dcraw prints a warning and reverts to the default.
-r red_mul -l blue_mul
Further adjust the color balance by multiplying the red and blue
channels by these values. Both default to 1.0.
Change the output brightness. Default is 1.0.
-s For cameras based on the Fuji Super CCD SR, use the secondary
sensors, in effect underexposing the image by four stops to
reveal detail in the highlights. For all other cameras, -s is
Flip the output image. The most common flips are 5 (90 degrees
CCW) and 6 (90 degrees clockwise). By default, dcraw tries to
use the flip specified by the camera. "-t 0" forces dcraw not
to flip images.
-2 Write eight bits per color value with a 99th-percentile white
point and the standard 0.45 gamma curve. Double the height if
necessary to correct the aspect ratio. This is the default.
-4 Write sixteen bits per color value. Output is linear with input
-- no white point, no gamma, same aspect ratio.
-3 Same image as -4, written in Adobe PhotoShop format. File
extension is ".psd".
ppm(5), ppm2tiff(1), pnmtotiff(1), pnmtopng(1), gphoto2(1).
The -w option does not work with many cameras.
No attempt is made to save camera settings or thumbnail images.
Author stubbornly refuses to add more output formats.
Don’t expect dcraw to produce the same images as software provided by
the camera vendor. Sometimes dcraw gives better results!
To balance the color, do "dcraw -h -b 0.5" and select a rectangle of
something that you know is white. Compute the average R, G, and B val-
ues for this area, then set red_mul and blue_mul to G/R and G/B.
Written by David Coffin, dcoffin a cybercom o net
January 19, 2005 dcraw(1)
Man(1) output converted with