PureJPEG

Remove Unnecessary Disclosure And Reduce The Size Of Your Images

By Dennis Forbes

Download PureJPEG (Win32 Command Line)

Introduction

PureJPEG is an easy to use, high performance utility to remove unnecessary data from images you email or post on the net, without affecting the image quality whatsoever (no decompression/recompression is performed in the filtration), removing such extraneous information as:

Digital camera technical data (EXIF)
Comment blocks
JPEG thumbnails
Application blocks

While you should never use this application on your personal image archive (where this information may actually serve a purpose in some scenarios), it is generally worthwhile to purify JPEG files when sharing images, or when posting images online.

Usage

PureJPEG is a command line application, and has three primary methods of execution.

purejpeg.exe : When no parameters are provided, files to process are taken from the console input, separated by linefeeds, until an EOF (Ctrl-Z) is encountered. Files are overwritten. This is most commonly used to pipe file lists between applications
purejpeg.exe [infilename] : When one parameter is provided, the parameter is used as the input file, and is subsequently used as the output file -- the original file is overwritten with the filtered output
purejpeg.exe [infilename] [outfilename] : When two parameters are provided, the first parameter is used as the input file, and the second is used as the output file

Examples

purejpeg.exe dogs.jpg : Filter extraneous information out of dogs.jpg in the current directory, overwriting the original only if no errors occur
purejpeg.exe dogs.jpg dogs_filtered.jpg : Filter extraneous information out of dogs.jpg, leaving the original while writing the new filtered output to dogs_filtered.jpg
dir /B /S /A-D *.jpg | purejpeg : This is a more complex piping for more advanced users. The first command (preceding the |) is a standard directory and subdirectory listing of all jpeg files in the current directory or any directory below it, with parameters causing the command to only list filenames without additional output. This filelist is piped to the pureJPEG application which very rapidly filters them one by one. If an error is encountered an error message will be emitted and the process will continue with the next file

FAQ

What Does This Cost?: Nothing. This trivial product was created using a very small amount of code from a revolutionary product that yafla will be releasing in the new year, and is offered as a public service. This is, as we've said, a very trivial product.
What Support Is Provided?: None. This product is released "as is" , and it is your responsibility to ensure that you have backups of all images which you process. While we are extremely confident in the quality of this product, it doesn't have a business model that justifies us shouldering any liability.
What's The Point?: Many people are unknowingly revealing information when they share pictures with friends and family, or when they post their pictures on the web (for instance on a blog or for an auction). This information includes a wide array of information, including the make and model of camera used, the exact date and time that the photo was taken, among a huge array of additional info. In addition some applications used to edit or view images quietly append identifying information onto your pictures. While this is often harmless disclosure, it's also completely unnecessary disclosure - if your readers don't need to know that you used an expensive new high-end digital camera to shoot your picture, then why tell them?
Okay, If I'm Not Paranoid Then What's The Point?: This additional information can significantly bulk up JPEGs - some images found on popular websites were found to be over 80% extraneous information. This is information that is of no value whatsoever to visitors (it does not alter the display of the image in any way), and it increases the transfer times and increases the bandwidth demands on the site. The longer a visitor waits for a bunch of irrelevant JPEG application blocks to transfer the more likely they click back and follow a different google result.
Do The Images Look Different After Filtering?: Not at all. Browsers skip the information that is filtered, as does Outlook and most other viewers.
So, Should I Wholesale Filter My Picture Archive?: Absolutely not! Some photo organization apps use this information to categorize pictures, and some applications you use to edit or view pictures use the application blocks for specialization. Unless you're running really short on hard drive space it's better to leave the data for personal archival.