Photos on your REX 6000
Aug 07 '01 (Updated Aug 10 '01)
The Bottom Line An Image-processing technique to get good-looking B&W photos on your REX 6000.
The REX 6000 has the ability to display pictures. You will have to do some extra work to do this. The pictures are only 240 x 120 pixels in resolution with two colors - black and white (not greyscale). Here I describe how to make the best of it and get some good B&W pictures into your REX 6000 PDA.
Preliminary Setup: First, you will need the "Tiny Draw" extra application to view bitmaps. Get it at this URL:
http://www14.u-page.so-net.ne.jp/ka2/idogawa/addin_r.html
(Sorry, epinions doesn't support hyperlinking any more!)
You will also need to know how to use REX Tools to upload this application along with any pictures you create into your REX. I won't go over that here. Below are steps I found effective to pre-process photos for good results on the REX's limited display. I use Adobe PhotoShop for this method. You should be able to translate this to any other imaging application. All of the tools I use are also available in Adobe's trimmed-down, cheaper version of PhotoShop. These instructions assume a basic knowledge of PhotoShop tools and techniques.
(1) Crop your photo to a 3:5 aspect ratio. You can accomplish this by constraining the rectangular marquee tool in PhotoShop to a 3x5 ratio in the Options palette. If your application can't do this, then do some math. Divide the shorter side by 3 and then multiply by 5 to get the longer dimension. For instance, 600x1000, 240x400...
(2) Change the photo to "greyscale". PhotoShop will ask if you want to discard the color information. This is ok.
(3) Resize the image to 240x120. You will have to turn off the option that sizes an image proportionally to do this, as the REX does not have square pixels. An equivalent image on the PC is 200x120. The REX just has more resolution horizontally that it has vertically. If you map a PC-resolution image directly into the REX without properly scaling it, the image will look squashed. This is why you must first get a picture with a 3:5 ratio, then resize it. Don't worry if the original greyscale image was smaller than 240x120.
If your image looks really stretched, then you probably put the wrong numbers in the wrong boxes. Undo the scaling operation, then try again, and reverse the two numbers. If the resulting image is longer in the vertical dimension, then you will have to rotate the image 90 degrees to make it longer horizontally.
(4) Apply "Auto Levels" from the Image/Adjust menu. This makes the whites whitest and the darks darkest, while making sure there is an even distribution of greys in the photo. To do this manually, you need to give the lightest white in the photo a level of 255, and the darkest black a level of zero, while spreading all of the greys that are in between and adjusting the gamma to correct the distribution. If all else fails, basic Brightness and Contrast adjustments will do the trick. Just be careful not to "blow out" the whites, or make the image too dark or washed out. If you have "Auto Levels", then this will do all of this for you, automatically.
(5) I'd recommend saving your intermediate source image at this step. Make sure to use a different file name, and not to erase your original image! Saving it here will allow you to "play" with the next steps to get the best results.
(6) Apply the "Unsharp Mask" Filter with an intensity of 75% and a radius of 4 pixels. This is a Sharpen filter with an aperature setting of 4 pixels. It enhances the contrast of course details in the image. The resulting image will look very severe, but this is necessary for the image to be viewable on the REX screen. If you don't have an Unsharp Mask filter, then play with the Sharpen filter to get the appropriate effect. Don't sharpen too much, or your image will turn into a bunch of hard lines with too little grey in between.
(7) Finally, convert the image into a "Bitmap" image. This is a two-color, dithered representation of the greyscale image. Leave the DPI setting as it is in PhotoShop, so the image isn't scaled, and set the dither pattern to "Diffusion". You want to preserve the 240x120 pixel size of the image.
(8) Save the image to a .BMP (Windows Bitmap) file, without compression. Now you can upload the file to your REX 6000 through REX Tools. Make sure that image scaling and dithering is turned off in REX Tools, while "invert" is turned on. Once the image is uploaded, you can view it with Tiny Draw.
The resulting image is rather course, but with the above image-processing techniques you can "push" the image to get the best possible detail while maintaining some of the greyscale shading. See what pictures will look like at my REX 6000 site:
http://gregsearle.tripod.com/rex_photos.html
(Sorry, Epinions doesn't allow hyperlinks any more)
 |
|
|
|
|
|
|
Epinions.com ID:
gsearle
|
 - Top 1000 |
|
Member: Greg Searle
Location: Nashua, NH
Reviews written: 27
Trusted by: 10 members
About Me:
Computer graphics designer and software developer with interests in technology, home improvement, and family life.
|
|
|
© 1999-2009 Shopping.com, Inc.