pfsview(1) [debian man page]
pfsview(1) General Commands Manual pfsview(1) NAME
pfsview - Viewer for high-dynamic range images in pfs format SYNOPSIS
pfsview [--window_min <log_lum>] [--window_max <log_lum>] DESCRIPTION
pfsview is a QT application for viewing high-dynamic range images. It expects pfs stream on the standard input and displays the frames in that stream one by one. pfsv script can be more convienent to use if hdr images are to be displayed without any prior processing. DYNAMIC RANGE WINDOW
To show high-dynamic range data on a low-dynamic range monitor, pfsview uses concept of a dynamic range window. The dynamic range window is the highest and lowest value that should be mapped to black and white pixel. Values above or below the window are clipped (see clipping methods below). The dynamic range window is displayed in pfsview as a blue area on the dynamic range scale (second toolbox from the top). The window can be moved, shrunk and expended using a mouse or a keyboard. CLIPPING METHODS
Currently, two clipping methods are available (see View menu): Simple clipping The values above and below the dynamic range window are displayed as black or white. Color-coded clipping The values above the dynamic range window are displayed as yellow and below the window as green. This is helpful to see which parts of the image do not fit into the selected dynamic range. Keep brightness and hue This method tries to preserve brightness and hue while sacrificing color saturation when the colors exceed the RGB color gamut. Col- ors are desaturated in the RGB color space towards the neutral color (D65) of the corresponding luminance. MAPPING METHODS
High-dynamic range data are usually better visualized using non-linear scale, for example a logarithmic or a power function. pfsview offers several such scales, shown in View menu. Gray-scale values for each mapping method are computed by the formulas: LINEAR: y = (x-min)/(max-min) GAMMA: y = [ (x-min)/(max-min) ]^gamma LOGARITHMIC: y = (log10(x)-log10(min))/(log10(max)-log10(min)) where y is the gray-scale value after mapping, x is an input HDR value, min and max are lower and upper bounds of the dynamic range window. OPTIONS
--window_min <log_lum> Lower bound of the values that should be displayed or minimum value of the dynamic range window. The value should be given in log_10 units, for example -1 if the lower bound should be 0.1 (10^-1). --window_max <log_lum> Upper bound of the values that should be displayed or minimum value of the dynamic range window. The value should be given in log_10 units, for example -1 if the upper bound should be 0.1 (10^-1). EXAMPLES
pfsin memorial.hdr | pfsview See the memorial image. pfsv memorial.hdr The same as above, but using the utility script 'pv'. SEE ALSO
pfsv(1) pfsin(1) BUGS
Zomming in may sometimes show artifacts. Please report bugs and comments to Rafal Mantiuk <mantiuk@mpi-sb.mpg.de>. pfsview(1)
Check Out this Related Man Page
pfstmo_mantiuk06(1) General Commands Manual pfstmo_mantiuk06(1) NAME
pfstmo_mantiuk06 - Tone mapping in the contrast domain SYNOPSIS
pfstmo_mantiuk06 [--factor <val>] [--equalize-contrast <val>] [--saturation <val>] [--verbose] [--quiet] [--help] DESCRIPTION
This command implements two tone mapping operators: contrast mapping and contrast equalization. Both operators can produce very sharp images (sometimes non-photorealistic) while minimizing contrast reversal (halo artifacts). More information on these operators can be found in: Rafal Mantiuk, Karol Myszkowski, Hans-Peter Seidel. A Perceptual Framework for Contrast Processing of High Dynamic Range Images In: ACM Transactions on Applied Perception 3 (3), pp. 286-308, 2006. http://www.mpi-inf.mpg.de/~mantiuk/contrast_domain/ This version contains several performance improvements made by Ed Brambley. If you find this TMO useful in your research project, please cite the paper above. The result of this TMO requires gamma correction. OPTIONS
--equalize-contrast <val>, -e <val> Use the contrast equalization algorithm. If this option is not specified, the contrast mapping algorithm will be used. The contrast equalization algorithm requires scaling parameter that controls the amount sharpenning, which can range from 0.1 (very sharp) to 1 (less sharp). contrast equalization results in very sharp, but also less natural images. contrast equalization may also enhance noise in low-qual- ity images. --factor <val>, -f <val> Contrast scaling factor (values 0-1) determines how much contrast magnitudes should be reduced. This option cannot be used with equalize-contrast. The lower value results in a sharper image. Default value: 0.3 --saturation <val>, -s <val> Saturation correction (values 0-1). The lower value results in stronger desaturation. Default value: 0.8 --verbose, -v Print additional information during program execution. --quiet, -q Do not display progress report. --help, -h Print list of commandline options. EXAMPLES
pfsin memorial.hdr | pfstmo_mantiuk06 -f 0.5 | pfsgamma -g 2.2 | pfsout memorial.png Tone map an image using contrast mapping and save it in the PNG format. pfsin memorial.hdr | pfstmo_mantiuk06 -e 0.5 | pfsgamma -g 2.2 | pfsout memorial.png The same as above, but use the contrast equalization algorithm. pfsin memorial.hdr | pfstmo_mantiuk06 -f 0.5 -s 1 | pfsview For optimal results you can output the result to pfsview and manually adjust the dynamic range window. Then save the image in pfsview by selecting 'Save image...' from the 'Frame' menu or pressing 's'. pfsin bridge.jpg --linear | pfsclamp --min 0.007 | pfstmo_mantiuk06 | pfsview Enhance the low-dynamic range image 'bridge' and view the result. pfsclamp command reduces noise for low code values. SEE ALSO
pfsgamma(1) pfsclamp(1) pfsin(1) pfsout(1) pfsview(1) BUGS
Please report bugs and comments to the pfstools discussion group (http://groups.google.com/group/pfstools). pfstmo_mantiuk06(1)