1dcraw(1) General Commands Manual dcraw(1)
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6 dcraw - command-line decoder for raw digital photos
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9 dcraw [OPTION]... [FILE]...
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12 dcraw decodes raw photos, displays metadata, and extracts thumbnails.
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15 -v Print verbose messages, not just warnings and errors.
16 -c Write decoded images or thumbnails to standard output.
18 -e Extract the camera-generated thumbnail, not the raw image.
20 You'll get either a JPEG or a PPM file, depending on the camera.
21 -z Change the access and modification times of an AVI, JPEG, TIFF
23 or raw file to when the photo was taken, assuming that the cam‐
24 era clock was set to Universal Time.
25 -i Identify files but don't decode them. Exit status is 0 if dcraw
27 can decode the last file, 1 if it can't. -i -v shows metadata.
28 dcraw cannot decode JPEG files!!
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32 -P deadpixels.txt
33 Read the dead pixel list from this file instead of ".badpixels".
34 See FILES for a description of the format.
35 -K darkframe.pgm
37 Subtract a dark frame from the raw data. To generate a dark
38 frame, shoot a raw photo with no light and do
39 dcraw -D -4 -j -t 0.
40 -k darkness
42 When shadows appear foggy, you need to raise the darkness level.
43 To measure this, apply pamsumm -mean to the dark frame generated
44 above.
45 -S saturation
47 When highlights appear pink, you need to lower the saturation
48 level. To measure this, take a picture of something shiny and
49 do dcraw -D -4 -j -c photo.raw | pamsumm -max
50 The default darkness and saturation are usually correct.
52 -n noise_threshold
54 Use wavelets to erase noise while preserving real detail. The
55 best threshold should be somewhere between 100 and 1000.
56 -C red_mag blue_mag
58 Enlarge the raw red and blue layers by the given factors, typi‐
59 cally 0.999 to 1.001, to correct chromatic aberration.
60 -H 0 Clip all highlights to solid white (default).
62 -H 1 Leave highlights unclipped in various shades of pink.
64 -H 2 Blend clipped and unclipped values together for a gradual fade
66 to white.
67 -H 3+ Reconstruct highlights. Low numbers favor whites; high numbers
69 favor colors. Try -H 5 as a compromise. If that's not good
70 enough, do -H 9, cut out the non-white highlights, and paste
71 them into an image generated with -H 3.
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74 By default, dcraw uses a fixed white balance based on a color chart
75 illuminated with a standard D65 lamp.
76 -w Use the white balance specified by the camera. If this is not
78 found, print a warning and use another method.
79 -a Calculate the white balance by averaging the entire image.
81 -A left top width height
83 Calculate the white balance by averaging a rectangular area.
84 First do dcraw -j -t 0 and select an area of neutral grey color.
85 -r mul0 mul1 mul2 mul3
87 Specify your own raw white balance. These multipliers can be
88 cut and pasted from the output of dcraw -v.
89 +M or -M
91 Use (or don't use) any color matrix from the camera metadata.
92 The default is +M if -w is set, -M otherwise. This option only
93 affects Olympus, Leaf, and Phase One cameras.
94 -o [0-5]
96 Select the output colorspace when the -p option is not used:
97 0 Raw color (unique to each camera)
99 1 sRGB D65 (default)
100 2 Adobe RGB (1998) D65
101 3 Wide Gamut RGB D65
102 4 Kodak ProPhoto RGB D65
103 5 XYZ
104 -p camera.icm [ -o output.icm ]
106 Use ICC profiles to define the camera's raw colorspace and the
107 desired output colorspace (sRGB by default).
108 -p embed
110 Use the ICC profile embedded in the raw photo.
111
113 -d Show the raw data as a grayscale image with no interpolation.
114 Good for photographing black-and-white documents.
115 -D Same as -d, but totally raw (no color scaling).
117 -h Output a half-size color image. Twice as fast as -q 0.
119 -q 0 Use high-speed, low-quality bilinear interpolation.
121 -q 1 Use Variable Number of Gradients (VNG) interpolation.
123 -q 2 Use Patterned Pixel Grouping (PPG) interpolation.
125 -q 3 Use Adaptive Homogeneity-Directed (AHD) interpolation.
127 -f Interpolate RGB as four colors. Use this if the output shows
129 false 2x2 meshes with VNG or mazes with AHD.
130 -m number_of_passes
132 After interpolation, clean up color artifacts by repeatedly
133 applying a 3x3 median filter to the R-G and B-G channels.
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136 By default, dcraw writes PGM/PPM/PAM with 8-bit samples, a BT.709 gamma
137 curve, a histogram-based white level, and no metadata.
138 -W Use a fixed white level, ignoring the image histogram.
140 -b brightness
142 Divide the white level by this number, 1.0 by default.
143 -g power toe_slope
145 Set the gamma curve, by default BT.709 (-g 2.222 4.5). If you
146 prefer sRGB gamma, use -g 2.4 12.92. For a simple power curve,
147 set the toe slope to zero.
148 -6 Write sixteen bits per sample instead of eight.
150 -4 Linear 16-bit, same as -6 -W -g 1 1.
152 -T Write TIFF with metadata instead of PGM/PPM/PAM.
154 -t [0-7,90,180,270]
156 Flip the output image. By default, dcraw applies the flip spec‐
157 ified by the camera. -t 0 disables all flipping.
158 -j For Fuji Super CCD cameras, show the image tilted 45 degrees.
160 For cameras with non-square pixels, do not stretch the image to
161 its correct aspect ratio. In any case, this option guarantees
162 that each output pixel corresponds to one raw pixel.
163 -s [0..N-1] or -s all
165 If a file contains N raw images, choose one or "all" to decode.
166 For example, Fuji Super CCD SR cameras generate a second image
167 underexposed four stops to show detail in the highlights.
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170 ./.badpixels, ../.badpixels, ../../.badpixels, ...
171 List of your camera's dead pixels, so that dcraw can interpolate
172 around them. Each line specifies the column, row, and UNIX time
173 of death for one pixel. For example:
174 962 91 1028350000 # died between August 1 and 4, 2002
176 1285 1067 0 # don't know when this pixel died
177 These coordinates are before any cropping or rotation, so use
179 dcraw -j -t 0 to locate dead pixels.
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182 pgm(5), ppm(5), pam(5), pamsumm(1), pnmgamma(1), pnmtotiff(1), pnm‐
183 topng(1), gphoto2(1), cjpeg(1), djpeg(1)
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186 Written by David Coffin, dcoffin a cybercom o net
187 May 14, 2009 dcraw(1)