DualMonitorWallpaperSwapper Readme

Introduction

Wallpapers designed for two monitors usually come as a single image that is designed to be spanned across them both. Some of them are designed to have the secondary monitor on the left, others on the right - but if your secondary monitor is not on the same side as the image artist's, then each half of the wallpaper is on the wrong monitor. You can swap the halves using Paint or Photoshop etc. but if you have lots of them, then it becomes a pain. This program is intended to fix this problem for you.

The program can be used easily with a command line for loop (Windows, Linux and MacOS each have a for loop facility in their respective command interpreters) to easily process a large number of images.

Anyways, give it a try and see if it works for you. Note that you need to have Java installed to run this program. See Usage below for more information.


Usage

Important: You need to have the Java binaries in your PATH environment variable. The Java installer might have done that for you automatically, but if running the program like below gives you an error that says java was not found, then you can use Google to find out how to do it.

To use DMWS, call it from your command line, like so:
java -jar dmws.jar <imagename> [imageformat]
where:
imagename is the filename of the image you want to process, and
imageformat is an optional argument that lets you specify the format you want the new image to be saved in. PNG, JPEG and Bitmap (BMP) are supported. If you do not specify an image format, DMWS will use PNG by default.
If you want to process a whole directory of images, you can use a for loop in your command interpreter. On Windows, you might try something like this:
for /f "tokens=*" %f in ('dir /b *.jpg') do java -jar dmws.jar "%f"
Add jpg to the end of that if you want the images to be saved as JPEGs, like this:
for /f "tokens=*" %f in ('dir /b *.jpg') do java -jar dmws.jar "%f" jpg
Your system will then go and process all the JPEGs in the current directory.


Notes

Unless you specify otherwise, DMWS will save images in PNG format by default (see Usage above). I recommend saving the resulting images in PNG format, because JPEG will introduce compression artefacts (no, "artefacts" is spelled correctly) and many JPEG wallpapers already have too many compression artefacts. PNG is a lossless image compression format, so it preserves exactly the content of the images. You may ask, if the image has already been compressed with JPEG once, what's the point of saving it in PNG? Well the answer to that is if you use this program on a JPEG and get it to save in JPEG, well the compression will be applied twice - if you used PNG it would only be applied once. You should get a few wallpapers from your collection and try with both JPEG and PNG, then preview them and flick between them to see if the difference is noticeable to you (don't forget to zoom in to actual size).

About JPEG Quality: Unfortunately, the image libraries built in to Java do not support different image quality levels, otherwise I would have implemented support for it. So, this program will not feature support for different JPEG quality unless Sun add support for it to the Java image libraries.



IMPORTANT: BY USING THIS PROGRAM, YOU ACKNOWLEDGE THAT YOU USE IT AT YOUR OWN RISK. THE AUTHOR ACCEPTS NO RESPONSIBILITY FOR ANY DATA LOSS OR OTHER DAMAGES CAUSED BY THIS PROGRAM. BY USING THIS PROGRAM, YOU AGREE TO THESE TERMS.
©2009 David Murphy. All rights reserved.