Display on LED sign - Revision history

Kurtk at 14:27, 23 May 2012

2012-05-23T14:27:02Z

Rfs: /* Connections */

2010-09-25T18:48:13Z

Connections

Kurtk: Added Gimp instructions, reference to Paul's hardware info, and script example

2008-03-24T18:43:39Z

Added Gimp instructions, reference to Paul's hardware info, and script example

Kurtk at 16:54, 21 March 2008

2008-03-21T16:54:54Z

Kurtk: multiple of 8 removed

2008-03-21T07:11:38Z

multiple of 8 removed

Kurtk: /* Some multiples of 8 */

2008-03-21T07:10:31Z

Some multiples of 8

Kurtk: multiples of 8 removed

2008-03-21T07:09:11Z

multiples of 8 removed

Kurtk: removed multiple of 8 requirement

2008-03-21T07:06:21Z

removed multiple of 8 requirement

Kurtk: /* Image preparation */

2008-03-17T21:03:54Z

Image preparation

Kurtk at 20:43, 17 March 2008

2008-03-17T20:43:27Z

New page

== The sign ==

The thrift store has a 128x48 red LED display sign.

This describes a general way to obtain and display images on the sign.

== Connections ==

It's driven by a serial port, the cable is plugged into the box on the back of the sign. Currently the other end of the cable is currently located in the server room and is intended to be plugged into ryukin. But any computer with a serial port can drive the display.

== Programs ==

== Pauls's ascii2leds ==

Paul Stoffregen's program (ascii2leds) takes an ascii image and displays on the LED. The ascii image consists of lines of text, 48 lines of 128 characters each. Blanks are black (non-lit LED) and non blank characters cause the associated LED to light.

usage:

ascii2led <file.text> [port]

== Kurt's ledpanel ==

Kurt Krueger's program takes a bitmap image in the PPM format. The PPM image can be generated by many image editing tools, the tool used this discussion is Xv.
The bitmap image can't be any taller than the display (48 bits) but can be of any length that's a multiple of 8. Images wider than the display are horizontally scrolled.

usage:

ledpanel <file.ppm> [threshold] [port]

== Image preparation ==

Xv's ''Grab'' feature allows one to prepare any image that can displayed on a computer for display on the LED sign. Images that are monochrome work best, but full color images will be converted to a b/w bitmap for display on the LED sign.

The first step is to get the image you want displayed on the computer monitor. This image can come from anywhere. Simple text messages can be created with OpenOffice Word Processor. The image should be about 48 bits high, this means using a font of around 24 points. More complicated images can be created with OpenOffice Presentation or The GIMP.

Note: GIMP can resize and write PPM files directly. The Xv steps can be skipped for GIMP processed images.

Start xv <<<< Need to establish an installed Xv location >>>>>. When the splash screen appears, press the right mouse button. That will bring up the control panel for xv. Press the ''Grab'' button. That will bring up a ''grab'' panel that explains usage. Press ''Grab'' (on ''grab'' panel), then use the middle button to drag a rectangular window over the part of the image desired. The area selected will replace the splash screen graphics. Strive for something less than 48 high.

The image needs to be sized to fit the criterion (less than 48 high, multiple of 8 wide). Pressing the '''S''' key brings up a resizing prompt. Type the new size in the same format as displayed in the prompt box (width x height). Press ''OK''. See below for a list of multiples of 8.

Save the image ''Save'' button. Choose format '''BPM/PGM/PPM (ascii)'''. Any file name will do, .ppm extension not required.

Run ledpanel: <<<<< need installed location for ledpanel >>>>>>

ledpanel <file>

The bitmap should appear on the LED panel.

The two optional parameters for ledpanel are a threshold valued used to convert grey scale images to b/w bitmap. The default is '''150''' which works for text images and works for color/greyscale images. Valid values are 1 thru 255. The second parameter is the serial port name. Default is '''/dev/ttyS0'''.

== Some multiples of 8 ==

128, 136, 144, 152, 160, 168, 176, 184, 192, 200, 208, 216, 224, 232, 240, 248, 256, 264, 272, 280, 288, 296, 304, 312, 320, 328, 336, 344, 352, 360, 368, 376

== Program locations ==

'''Subject to change'''

''ledpanel'' and ''xv'' are currently located on ryukin under /home/kurtk. There are version built for both Dapper and Feisty.

Xv is a bit persnickity running on a Dapper or Feisty desktop with a wheel mouse. I've had very good behavior on Thinkpad laptops. If one wants
to try the code, it would be best when I (Kurt) am around. This is usually Thursdays (AM in build, PM in laptops).

== Enhancements, TO DO, etc. ==

The multistep xv manipulation can be done with X11 programming and would only involve a single step to select the are to be displayed. The size restrictions (including the multiple of 8) can be removed, and vertical scrolling can be implemented.

Future development depends an buy in to this concept. This means someone has to use the Xv method to drive the sign for a while.
Then a streamlined program can be written using what's been learned.

← Older revision		Revision as of 14:27, 23 May 2012
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		+	== The sign no longer exists, page should be deleted ==
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	== The sign ==		== The sign ==

← Older revision		Revision as of 16:54, 21 March 2008
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	Future development depends an buy in to this concept. This means someone has to use the Xv method to drive the sign for a while.		Future development depends an buy in to this concept. This means someone has to use the Xv method to drive the sign for a while.
	Then a streamlined program can be written using what's been learned.		Then a streamlined program can be written using what's been learned.
		+
		+	[[Category:howto]]

← Older revision		Revision as of 07:10, 21 March 2008
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	The two optional parameters for ledpanel are a threshold valued used to convert grey scale images to b/w bitmap. The default is '''150''' which works for text images and works for color/greyscale images. Valid values are 1 thru 255. The second parameter is the serial port name. Default is '''/dev/ttyS0'''.		The two optional parameters for ledpanel are a threshold valued used to convert grey scale images to b/w bitmap. The default is '''150''' which works for text images and works for color/greyscale images. Valid values are 1 thru 255. The second parameter is the serial port name. Default is '''/dev/ttyS0'''.

−	~~== Some multiples of 8 ==~~
−
−	~~128, 136, 144, 152, 160, 168, 176, 184, 192, 200, 208, 216, 224, 232, 240, 248, 256, 264, 272, 280, 288, 296, 304, 312, 320, 328, 336, 344, 352, 360, 368, 376~~

@@ Line 41: / Line 41: @@
 Start xv <<<< Need to establish an installed Xv location >>>>>.  When the splash screen appears, press the right mouse button.  That will bring up the control panel for xv.  Press the ''Grab'' button.  That will bring up a ''grab'' panel that explains usage. Press ''Grab'' (on ''grab'' panel), then use the middle button to drag a rectangular window over the part of the image desired.  The area selected will replace the splash screen graphics.  Strive for something less than 48 high.
-The image needs to be sized to fit the criterion (48 or less high, multiple of 8 wide).  Pressing the '''S''' key brings up a resizing prompt.  Type the new size in the same format as displayed in the prompt box  (width x height).  Press ''OK''.  See below for a list of multiples of 8.
+The image may need to be sized to fit the criterion of 48 or less high.  Pressing the '''S''' key brings up a resizing prompt.  Type the new size in the same format as displayed in the prompt box  (width x height).  Press ''OK''.
 Save the image ''Save'' button.  Choose format '''BPM/PGM/PPM (ascii)'''.  Any file name will do, .ppm extension not required.

@@ Line 9: / Line 9: @@
 == Connections ==
-It's driven by a serial port, the cable is plugged into the box on the back of the sign.  Currently the other end of the cable is currently located in the server room and is intended to be plugged into ryukin.  But any computer with a serial port can drive the display.
+It's driven by a serial port, the cable is plugged into the box on the back of the sign.  Currently the other end of the cable is currently located in the server room and is intended to be plugged into [[Free Geek's internal application server]].  But any computer with a serial port can drive the display.
 == Programs ==

@@ Line 4: / Line 4: @@
 This describes a general way to obtain and display images on the sign.
 == Connections ==
@@ Line 24: / Line 26: @@
 == Kurt's ledpanel ==
-Kurt Krueger's program takes a bitmap image in the PPM format.  The PPM image can be generated by many image editing tools, the tool used this discussion is Xv.
+Kurt Krueger's program takes a bitmap image in the PPM format.  The PPM image can be generated by many image editing tools, the tools used this discussion are Xv and The Gimp.  The bitmap image can't be any taller than the display (48 bits) but can be of any length.  Images wider than the display are horizontally scrolled.
 usage:
@@ Line 31: / Line 32: @@
 ledpanel <file.ppm> [threshold] [port]
-== Image preparation ==
+== Image preparation with Xv==
 Xv's ''Grab'' feature allows one to prepare any image that can displayed on a computer for display on the LED sign.  Images that are monochrome work best, but full color images will be converted to a b/w bitmap for display on the LED sign.
@@ Line 39: / Line 40: @@
 Note: GIMP can resize and write PPM files directly.  The Xv steps can be skipped for GIMP processed images.
-Start xv <<<< Need to establish an installed Xv location >>>>>.  When the splash screen appears, press the right mouse button.  That will bring up the control panel for xv.  Press the ''Grab'' button.  That will bring up a ''grab'' panel that explains usage. Press ''Grab'' (on ''grab'' panel), then use the middle button to drag a rectangular window over the part of the image desired.  The area selected will replace the splash screen graphics.  Strive for something less than 48 high.
+Start xv <<<< Need to establish an installed Xv location >>>>>.
 The image may need to be sized to fit the criterion of 48 or less high.  Pressing the '''S''' key brings up a resizing prompt.  Type the new size in the same format as displayed in the prompt box  (width x height).  Press ''OK''.
 Save the image ''Save'' button.  Choose format '''BPM/PGM/PPM (ascii)'''.  Any file name will do, .ppm extension not required.
 Run ledpanel:   <<<<< need installed location for ledpanel >>>>>>
@@ Line 60: / Line 90: @@
 ''ledpanel'' and ''xv'' are currently located on ryukin under /home/kurtk.  There are version built for both Dapper and Feisty.
 Xv is a bit persnickity running on a Dapper or Feisty desktop with a wheel mouse.  I've had very good behavior on Thinkpad laptops.  If one wants
@@ Line 67: / Line 99: @@
 == Enhancements, TO DO, etc. ==
-The multistep xv manipulation can be done with X11 programming and would only involve a single step to select the are to be displayed.  The size restrictions can be removed, and vertical scrolling can be implemented.
+The multistep xv/Gimp manipulation can be done with X11 programming and would only involve a single step to select the are to be displayed.  The size restrictions can be removed, and vertical scrolling can be implemented.
-Future development depends an buy in to this concept.  This means someone has to use the Xv method to drive the sign for a while.
+Future development depends on buy in to this concept.  This means someone has to use the Xv/Gimp method to drive the sign for a while.
 Then a streamlined program can be written using what's been learned.
 [[Category:howto]]

@@ Line 42: / Line 42: @@
 Start xv <<<< Need to establish an installed Xv location >>>>>.  When the splash screen appears, press the right mouse button.  That will bring up the control panel for xv.  Press the ''Grab'' button.  That will bring up a ''grab'' panel that explains usage. Press ''Grab'' (on ''grab'' panel), then use the middle button to drag a rectangular window over the part of the image desired.  The area selected will replace the splash screen graphics.  Strive for something less than 48 high.
-The image needs to be sized to fit the criterion (less than 48 high, multiple of 8 wide).  Pressing the '''S''' key brings up a resizing prompt.  Type the new size in the same format as displayed in the prompt box  (width x height).  Press ''OK''.  See below for a list of multiples of 8.
+The image needs to be sized to fit the criterion (48 or less high, multiple of 8 wide).  Pressing the '''S''' key brings up a resizing prompt.  Type the new size in the same format as displayed in the prompt box  (width x height).  Press ''OK''.  See below for a list of multiples of 8.
 Save the image ''Save'' button.  Choose format '''BPM/PGM/PPM (ascii)'''.  Any file name will do, .ppm extension not required.
@@ Line 53: / Line 53: @@
 The two optional parameters for ledpanel are a threshold valued used to convert grey scale images to b/w bitmap.  The default is '''150''' which works for text images and works for color/greyscale images.  Valid values are 1 thru 255.  The second parameter is the serial port name.  Default is '''/dev/ttyS0'''.
 == Some multiples of 8 ==