| 1 | greg | 1.1 | .\" RCSid "$Id" | 
| 2 |  |  | .TH XIMAGE 1 10/27/98 RADIANCE | 
| 3 |  |  | .SH NAME | 
| 4 |  |  | ximage - RADIANCE driver for X window system | 
| 5 |  |  | .SH SYNOPSIS | 
| 6 |  |  | .B ximage | 
| 7 |  |  | [ | 
| 8 |  |  | .B \=geometry | 
| 9 |  |  | ][ | 
| 10 |  |  | .B "\-di display" | 
| 11 |  |  | ][ | 
| 12 |  |  | .B "\-c ncolors" | 
| 13 |  |  | ][ | 
| 14 |  |  | .B \-d | 
| 15 |  |  | ][ | 
| 16 |  |  | .B \-b | 
| 17 |  |  | ][ | 
| 18 |  |  | .B \-m | 
| 19 |  |  | ][ | 
| 20 |  |  | .B "\-g gamma" | 
| 21 |  |  | ][ | 
| 22 |  |  | .B \-f | 
| 23 |  |  | ][ | 
| 24 |  |  | .B "\-e spec | 
| 25 |  |  | ][ | 
| 26 |  |  | .BI -o spec | 
| 27 |  |  | ][ | 
| 28 |  |  | .B "\-t intvl" | 
| 29 |  |  | ][ | 
| 30 |  |  | .B \-s | 
| 31 |  |  | ] | 
| 32 |  |  | .B "picture .." | 
| 33 |  |  | .SH DESCRIPTION | 
| 34 |  |  | .I Ximage | 
| 35 |  |  | takes one or more RADIANCE picture files | 
| 36 |  |  | and displays them on an X server. | 
| 37 |  |  | The | 
| 38 |  |  | .I \-c | 
| 39 |  |  | option specifies the number of colors to use (default fills color table). | 
| 40 |  |  | The | 
| 41 |  |  | .I \-d | 
| 42 |  |  | option turns off color dithering. | 
| 43 |  |  | The | 
| 44 |  |  | .I \-b | 
| 45 |  |  | option displays the image in black and white (greyscale). | 
| 46 |  |  | The | 
| 47 |  |  | .I \-m | 
| 48 |  |  | option forces monochrome output. | 
| 49 |  |  | The | 
| 50 |  |  | .I \-g | 
| 51 |  |  | option specifies the exponent used in gamma correction; | 
| 52 |  |  | the default value is 2.2. | 
| 53 |  |  | The | 
| 54 |  |  | .I \-f | 
| 55 |  |  | option stores a Pixmap on the server side for faster refresh. | 
| 56 |  |  | This may not work with large images on some servers. | 
| 57 |  |  | The | 
| 58 |  |  | .I \-o | 
| 59 |  |  | option specifies a sequence of information to print to the standard | 
| 60 |  |  | output for the 't' command (see below). | 
| 61 |  |  | The | 
| 62 |  |  | .I \-t | 
| 63 |  |  | option specifies a minimum interval (in milliseconds) | 
| 64 |  |  | between successive ray outputs | 
| 65 |  |  | in mouse tracking mode (right button pressed). | 
| 66 |  |  | .PP | 
| 67 |  |  | The | 
| 68 |  |  | .I \-e | 
| 69 |  |  | option specifies an exposure compensation in f-stops (powers of two). | 
| 70 |  |  | Only integer stops are allowed, for efficiency. | 
| 71 |  |  | If the special word, | 
| 72 |  |  | .I auto | 
| 73 |  |  | is given instead of a number of stops, then | 
| 74 |  |  | .I ximage | 
| 75 |  |  | performs an automatic exposure adjustment similar to | 
| 76 |  |  | .I pcond(1), | 
| 77 |  |  | compressing the dynamic range of the image to fit | 
| 78 |  |  | within the dynamic range of the display. | 
| 79 |  |  | If the special word, | 
| 80 |  |  | .I human | 
| 81 |  |  | is given instead, then | 
| 82 |  |  | .I ximage | 
| 83 |  |  | performs an exposure adjustment similar to | 
| 84 |  |  | .I pcond | 
| 85 |  |  | with the | 
| 86 |  |  | .I \-s | 
| 87 |  |  | and | 
| 88 |  |  | .I \-c | 
| 89 |  |  | options, which compensate for human contrast and color sensitivity | 
| 90 |  |  | at the corresponding scene luminance levels. | 
| 91 |  |  | This option yeilds and appearance of the scene on the display that | 
| 92 |  |  | closely matches what would be experienced in the real world. | 
| 93 |  |  | .PP | 
| 94 |  |  | The | 
| 95 |  |  | .I \-s | 
| 96 |  |  | option tells | 
| 97 |  |  | .I ximage | 
| 98 |  |  | to display multiple pictures sequentially, rather than all at once. | 
| 99 |  |  | If no | 
| 100 |  |  | .I picture | 
| 101 |  |  | is given, input is read from stdin provided either the | 
| 102 |  |  | .I \-b | 
| 103 |  |  | or | 
| 104 |  |  | .I \-m | 
| 105 |  |  | option is in effect, or the X server is capable of 24-bit color. | 
| 106 |  |  | However, many of the commands given below will not work. | 
| 107 |  |  | .SH COMMANDS | 
| 108 |  |  | Once a picture is displayed, the user | 
| 109 |  |  | may perform a number of operations. | 
| 110 |  |  | Some of the operations make use of an area of interest, defined by pressing | 
| 111 |  |  | the left mouse button and dragging the cursor over a section of the image. | 
| 112 |  |  | Pressing the button and immediately releasing it defines a single point as | 
| 113 |  |  | the area of interest. | 
| 114 |  |  | A command is a single character. | 
| 115 |  |  | .TP 10n | 
| 116 |  |  | .BR q | 
| 117 |  |  | Quit picture. | 
| 118 |  |  | (Also Q or ^D.)\0 | 
| 119 |  |  | .TP 10 | 
| 120 |  |  | .BR <space> | 
| 121 |  |  | Redraw the area of interest. | 
| 122 |  |  | .TP 10 | 
| 123 |  |  | .BR ^R | 
| 124 |  |  | Redraw the entire image. | 
| 125 |  |  | .TP | 
| 126 |  |  | .BR <return> | 
| 127 |  |  | Display the radiance averaged over the area of interest. | 
| 128 |  |  | .TP | 
| 129 |  |  | .BR l | 
| 130 |  |  | Display the luminance value in the area of interest. | 
| 131 |  |  | This assumes that the image was correctly computed in terms of | 
| 132 |  |  | luminance. | 
| 133 |  |  | .TP | 
| 134 |  |  | .BR c | 
| 135 |  |  | Display the color in the area of interest. | 
| 136 |  |  | .TP | 
| 137 |  |  | .BR p | 
| 138 |  |  | Display the x and y location of the cursor. | 
| 139 |  |  | .TP | 
| 140 |  |  | .BR i | 
| 141 |  |  | Identify identical pixels by assigning a random color at the cursor position. | 
| 142 |  |  | This is useful for displaying contours, especially when combined | 
| 143 |  |  | with the -b option. | 
| 144 |  |  | .TP | 
| 145 |  |  | .BR t | 
| 146 |  |  | Print information about the pixel under the cursor | 
| 147 |  |  | according to the string following the | 
| 148 |  |  | .I \-o | 
| 149 |  |  | command line option. | 
| 150 |  |  | The valid characters for this option correspond roughly to the other | 
| 151 |  |  | .I ximage | 
| 152 |  |  | commands: | 
| 153 |  |  | .IP | 
| 154 |  |  | o       ray origin | 
| 155 |  |  | .IP | 
| 156 |  |  | d       ray direction | 
| 157 |  |  | .IP | 
| 158 |  |  | v       radiance value | 
| 159 |  |  | .IP | 
| 160 |  |  | l       luminance value | 
| 161 |  |  | .IP | 
| 162 |  |  | p       pixel position | 
| 163 |  |  | .IP | 
| 164 |  |  | The default output is "-ood", which prints | 
| 165 |  |  | the ray origin and direction. | 
| 166 |  |  | This can be used as input to rtrace(1) to get additional information | 
| 167 |  |  | about the image (ie. pipe the output of ximage into rtrace). | 
| 168 |  |  | Pressing the middle mouse button is equivalent to typing the 't' key. | 
| 169 |  |  | Pressing and holding the right mouse button is equivalent to | 
| 170 |  |  | continuously pressing the 't' key. | 
| 171 |  |  | .TP | 
| 172 |  |  | .BR = | 
| 173 |  |  | Adjust the exposure to the area of interest. | 
| 174 |  |  | A crude adjustment is made immediately, and the number of stops | 
| 175 |  |  | is printed while the colors are resampled. | 
| 176 |  |  | After a few seconds to a minute, the final image is redisplayed. | 
| 177 |  |  | If the area of interest is already within 1/2 stop of the ideal, | 
| 178 |  |  | no adjustment is made. | 
| 179 |  |  | .TP | 
| 180 |  |  | .BR @ | 
| 181 |  |  | Same as '=' command, only the exposure is adjusted to provide | 
| 182 |  |  | roughly the same visibility for the selected region | 
| 183 |  |  | on screen as a viewer would experience | 
| 184 |  |  | in the actual space. | 
| 185 |  |  | Like the 'l' command, this adjustment assumes that the image | 
| 186 |  |  | has been correctly computed in terms of luminance. | 
| 187 |  |  | (See also the 'h' command, below.) | 
| 188 |  |  | .TP | 
| 189 |  |  | .BR a | 
| 190 |  |  | Perform automatic exposure compensation, as if | 
| 191 |  |  | .I ximage | 
| 192 |  |  | were started with the | 
| 193 |  |  | .I "\-e auto" | 
| 194 |  |  | option. | 
| 195 |  |  | If a rectangular area has been selected, the pixels in this region | 
| 196 |  |  | will be emphasized in the histogram, offering this area exposure preference. | 
| 197 |  |  | (Each pixel within the rectangle will be weighted as 21 outside pixels.) | 
| 198 |  |  | .TP | 
| 199 |  |  | .BR h | 
| 200 |  |  | Perform human expsoure compensation, as if | 
| 201 |  |  | .I ximage | 
| 202 |  |  | were started with the | 
| 203 |  |  | .I "\-e human" | 
| 204 |  |  | option. | 
| 205 |  |  | See the 'a' command above regarding pixel weighting. | 
| 206 |  |  | .TP | 
| 207 |  |  | .BR 0 | 
| 208 |  |  | Reset the origin to the upper left corner of the image. | 
| 209 |  |  | This command is used to restore the original image position after | 
| 210 |  |  | using the shift or control key with the mouse to relocate the image | 
| 211 |  |  | within the frame (see below). | 
| 212 |  |  | .TP | 
| 213 |  |  | .BR f | 
| 214 |  |  | Switch on the fast redraw option | 
| 215 |  |  | .I (\-f), | 
| 216 |  |  | loading the image pixmap over to the server side. | 
| 217 |  |  | This command is useful when network delays are causing slow image | 
| 218 |  |  | refresh, and the user didn't notice it until after | 
| 219 |  |  | .I ximage | 
| 220 |  |  | was started. | 
| 221 |  |  | .TP | 
| 222 |  |  | .BR F | 
| 223 |  |  | Switch off the fast redraw option. | 
| 224 |  |  | This frees up some memory on the server, as well as the color table | 
| 225 |  |  | for other windows. | 
| 226 |  |  | .PP | 
| 227 |  |  | In addition to the commands listed above, the control or shift key may | 
| 228 |  |  | be held while the cursor is dragged to reposition the image within the | 
| 229 |  |  | window. | 
| 230 |  |  | .SH "X RESOURCES" | 
| 231 |  |  | radiance.gamma  the default gamma correction value | 
| 232 |  |  | .SH ENVIRONMENT | 
| 233 |  |  | DISPLAY_GAMMA           the default gamma correction value | 
| 234 |  |  | .SH AUTHORS | 
| 235 |  |  | Greg Ward | 
| 236 |  |  | .br | 
| 237 |  |  | Anat Grynberg (Paris) | 
| 238 |  |  | .br | 
| 239 |  |  | Philip Thompson (MIT) | 
| 240 |  |  | .SH "SEE ALSO" | 
| 241 |  |  | aedimage(1), normtiff(1), pcond(1), pfilt(1), rpict(1), rtrace(1), | 
| 242 |  |  | rview(1), xglaresrc(1), xshowtrace(1) |