## DCRaw reference

Here's an excerpt from DCRaw's man page (Retrieved: October 30, 2007).

-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, TIFF 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 1
  Use Variable Number of Gradients (VNG) interpolation.
-q 2
  Use Patterned Pixel Grouping (PPG) 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.
-m number_of_passes
  After interpolation, clean up color artifacts by repeatedly applying a 3x3 median filter to the R-G and B-G channels.
-n noise_threshold
  Use wavelets to erase noise while preserving real detail. The best threshold should be somewhere between 100 and 1000.
-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.
-T
  Write TIFF output (with metadata) instead of PGM/PPM/PAM.
-k black
  Set the black point. Default depends on the camera.
-K darkframe.pgm
  Subtract a dark frame from the raw data. To generate a dark frame, shoot a raw photo with no light and do dcraw -D -4 -j -t 0.
-w
  Use the white balance specified by the camera. If this is not found, print a warning and use another method.
-a
  Calculate the white balance by averaging the entire image.
-A left top width height
  Calculate the white balance by averaging a rectangular area. First do dcraw -j -t 0 and select an area of neutral grey color.
-r mul0 mul1 mul2 mul3
  Specify your own raw white balance. These multipliers can be cut and pasted from the output of dcraw -v.
no white balance option
  Use a fixed white balance based on a color chart illuminated with a standard D65 lamp.
+M or -M
  Use (or don't use) any color matrix from the camera metadata. The default is +M if -w is set, -M otherwise. This option only affects Olympus, Leaf, and Phase One cameras.
-C red_mag blue_mag
  Enlarge the raw red and blue layers by the given factors, typically 0.999 to 1.001, to correct chromatic aberration.
-H 0
  Clip all highlights to solid white (default).
-H 1
  Leave highlights unclipped in various shades of pink.
-H 2
  Blend clipped and unclipped values together for a gradual fade to white.
-H 3-9
  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.
-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 RGB (1998) D65
          3   Wide Gamut RGB D65
          4   Kodak ProPhoto RGB 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.
-s [0..N-1] or -s all
  If a file contains N raw images, choose one or "all" to decode. For example, Fuji Super CCD SR cameras generate a second image underexposed four stops to show detail in the highlights.
-j
  For Fuji Super CCD cameras, show the image tilted 45 degrees. For cameras with non-square pixels, do not stretch the image to its correct aspect ratio. In any case, this option guarantees that each output pixel corresponds to one raw pixel.