pfsglview(1)

1pfsglview(1)                General Commands Manual               pfsglview(1)
2
3
4

NAME

6       pfsglview - Viewer for high-dynamic range images in pfs format
7

SYNOPSIS

9       pfsglview [--h] [--v]
10

DESCRIPTION

12       pfsview  is  a  OpenGL/GLUT  application for viewing high-dynamic range
13       images. It expects pfs stream on the standard input  and  displays  the
14       frames in that stream one by one.
15
16

DYNAMIC RANGE WINDOW

18       To  show  high-dynamic  range data on a low-dynamic range monitor, pfs‐
19       glview uses concept of a dynamic range window. The dynamic range window
20       is  the  highest  and  lowest  value that should be mapped to black and
21       white pixel. Values above or below the window are clipped (see clipping
22       methods below). The dynamic range window is displayed in pfsglview as a
23       blue area on the dynamic range scale (second toolbox from the top). The
24       window can be moved, shrunk and expended using a mouse or a keyboard.
25
26

ZOOMING AND PANNING

28       To  zoom image, the mouse can be dragged in vertical direction with the
29       left button pressed.  Pressing [space] button or  pressing  left  mouse
30       button  above  the  statistic  window (left-bottom corner) changes from
31       zooming to panning modes and vice versa. To pan image, the mouse can be
32       dragged  in  vertical  and  horizontal  directions with the left button
33       pressed.
34
35

POPUP MENU OPTIONS

37       Zoom reset
38              Set default zoom parameters.
39
40       Zoom in
41              Increase image (mouse dragging with left button pressed).
42
43       Zoom out
44              Decrease image (mouse dragging with left button pressed).
45
46       Increase exposure
47              Move dynamic range window into higher luminance values.
48
49       Decrease exposure
50              Move dynamic range window into lover luminance values.
51
52       Extend dynamic range
53              Extend dynamic range window.
54
55       Shrink dynamic range
56              Shrink dynamic range window
57
58       Low dynamic range
59              Set dynamic range window to <-1,1> range (log scale).
60
61       Fit to dynamic range
62              Set dynamic range windo to minimum and maximum  luminance  of  a
63              given image.
64
65       Choose channel
66              Change image data channel.
67
68       Mapping method
69              Change mapping method (see below for details).
70
71       Next frame
72              Display next image from the pipe.
73
74       Previous frame
75              Display previous image from the pipe.
76
77       Histogram
78              Switch on/off histogram window.
79
80       Info   Switch on/off info window.
81
82       Save&Quit
83              Send  the  visible  LDR  image  (8-bits) to stdout and quit pfs‐
84              glview.
85
86
87

MAPPING METHODS

89       High-dynamic range data are usually better visualized using  non-linear
90       scale,  for example a logarithmic or a power function. pfsglview offers
91       several such scales, shown in popup menu. Gray-scale  values  for  each
92       mapping method are computed by the formulas:
93
94       LINEAR: y = (x-min)/(max-min)
95
96       GAMMA: y = [ (x-min)/(max-min) ]^gamma
97
98       LOGARITHMIC: y = (log10(x)-log10(min))/(log10(max)-log10(min))
99
100       where y is the gray-scale value after mapping, x is an input HDR value,
101       min and max are lower and upper bounds of the dynamic range window.
102
103

EXAMPLES

105       pfsin memorial.hdr | pfsglview
106              See the memorial image.
107
108       pfsin memorial.hdr | pfsglview | pfsout memorial.jpg
109              See the memorial image and save the clipped (8-bits) version  to
110              memorial.jpg  (Save&Quit  option from popup menu should be acti‐
111              vated).
112
113