NAME

       pfsglview - Viewer for high-dynamic range images in pfs format

SYNOPSIS

       pfsglview [--h] [--v]

DESCRIPTION

       pfsview is a OpenGL/GLUT 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.

DYNAMIC RANGE WINDOW

       To show high-dynamic range data on a low-dynamic range monitor, pfsglview 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 pfsglview 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.

ZOOMING AND PANNING

       To  zoom  image,  the  mouse  can  be  dragged  in vertical direction with the left button
       pressed.  Pressing [space] button or pressing left mouse button above the statistic window
       (left-bottom  corner)  changes from zooming to panning modes and vice versa. To pan image,
       the mouse can be dragged in vertical  and  horizontal  directions  with  the  left  button
       pressed.

POPUP MENU OPTIONS

       Zoom reset
              Set default zoom parameters.

       Zoom in
              Increase image (mouse dragging with left button pressed).

       Zoom out
              Decrease image (mouse dragging with left button pressed).

       Increase exposure
              Move dynamic range window into higher luminance values.

       Decrease exposure
              Move dynamic range window into lover luminance values.

       Extend dynamic range
              Extend dynamic range window.

       Shrink dynamic range
              Shrink dynamic range window

       Low dynamic range
              Set dynamic range window to <-1,1> range (log scale).

       Fit to dynamic range
              Set dynamic range windo to minimum and maximum luminance of a given image.

       Choose channel
              Change image data channel.

       Mapping method
              Change mapping method (see below for details).

       Next frame
              Display next image from the pipe.

       Previous frame
              Display previous image from the pipe.

       Histogram
              Switch on/off histogram window.

       Info   Switch on/off info window.

       Save&Quit
              Send the visible LDR image (8-bits) to stdout and quit pfsglview.

MAPPING METHODS

       High-dynamic  range data are usually better visualized using non-linear scale, for example
       a logarithmic or a power function. pfsglview offers several such scales,  shown  in  popup
       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.

EXAMPLES

       pfsin memorial.hdr | pfsglview
              See the memorial image.

       pfsin memorial.hdr | pfsglview | pfsout memorial.jpg
              See the memorial image and  save  the  clipped  (8-bits)  version  to  memorial.jpg
              (Save&Quit option from popup menu should be activated).

SEE ALSO

       pfsin(1)

       Please report bugs and comments to Radoslaw Mantiuk <radoslaw.mantiuk@gmail.com>.

                                                                                     pfsglview(1)