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Add a Readme file.
author David Barts <n5jrn@me.com>
date Sat, 11 Apr 2020 11:24:25 -0700
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1 <!DOCTYPE html>
2 <html>
3 <head>
4 <meta http-equiv="content-type" content="text/html; charset=UTF-8">
5 <title>Introducing ExifWasher</title>
6 <style>
7 html { font-family: "TeX Gyre Schola", serif; }
8 h1, h2, h3, h4, h5, h6 { font-family: "Avenir Next", sans-serif; }
9 pre, code, kbd, samp { font-family: "Menlo", monospace; font-size: 85%; }
10 </style>
11 </head>
12 <body>
13 <h1>Indroducing ExifWasher</h1>
14 <h2>Executive Summary</h2>
15 <p>This program makes it easy to remove metadata from the digital images you
16 create.</p>
17 <h2>What is “Metadata” and Why Would I Want to Remove It?</h2>
18 <p>You may not realize it, but image files can (and typically do!) contain
19 more than just image data. These data can include your camera make, model,
20 and serial number; the location where you took the photo; the software you
21 used to edit the photo (and what editing steps you did); etc.</p>
22 <p>One of the most powerful uses of photography is to graphically document
23 things that the wealthy and powerful might wish to remain concealed. The
24 evils of slavery, child labor, poverty, war, and imperialism have all been
25 documented photographically, and such photographs have often proved
26 instrumental in helping to motivate social change.</p>
27 <p>Because of the metadata they contain, digital photographs contain data
28 which has been used to determine who took them, and in some cases to exact
29 retribution against their photographers. ExifWasher makes it easy to see
30 and remove the privacy-compromising metadata in your images.</p>
31 <p>Even if your images are not of such a sensitive nature, that extra data
32 takes up space. It is not uncommon for a 100 KiB image to contain 20 KiB
33 of metadata in it; if that image is on a web page, that makes for 20 KiB
34 of wasted network usage each time the image is sent.</p>
35 <h2>What Makes ExifWasher Different from Other Metadata Editors?</h2>
36 <p>Simply put, it is designed to <em>safely</em> remove <em>unimportant</em>
37 metadata.</p>
38 <p>There are plenty of general-purpose image metadata editors out there, and
39 these tools can be employed to remove unimportant metadata. The trouble
40 is, they are not user-friendly: it is up to you, the user, to know which
41 metadata are unimportant, and to delete it.</p>
42 <p>There can be literally <em>hundreds</em> of bits of metadata in an
43 image, and <em>not all are safe to remove</em>. In particular, if you
44 accidentally remove color-management metadata, computers that don’t handle
45 images without color-management metadata properly (I’m talking about <em>you</em>,
46 Apple Computer, Inc.) will display colors that often look all “washed-out”
47 or otherwise incorrect.</p>
48 <p>Likewise, there are already plenty of simple-to-use, user-friendly tools
49 out there for cleaning the metadata out of image files, but they
50 inevitably delete <em>all</em> metadata, resulting in files that often
51 display improperly. Also of concern, many of these “tools” are actually
52 online services. If you’re concerned about your privacy, why would you
53 trust the images you’re processing to some unknown third party, who may be
54 linked somehow to those who might want to retaliate against you.</p>
55 <p>I wrote this program because I wanted there to be a quick, easy way to
56 scrub images before they even left a photographer’s computer and made
57 their way onto the Internet, and for that program to leave vital metadata
58 alone, so that the resulting images continue to display properly.</p>
59 <h2>ExifWasher Washes More than Just Exif Metadata</h2>
60 <p>Exif is the most common type of metadata, but image files commonly
61 contain compromising XMP or IPTC data, particularly if they have been
62 edited with a tool like Photoshop. ExifWasher will seamlessly deal with
63 these kinds of metadata, too. It tries to do as thorough a job as possible
64 of scrubbing possibly compromising metadata from your images.</p>
65 <h2>Using ExifWasher</h2>
66 <p>Just double-click on the ExifWasher icon and a main window should open
67 up. Either choose the File… Wash from the menu bar, or just drag image
68 files onto the main ExifWasher image.</p>
69 <p>When ExifWasher opens an image, it displays all the metadata it finds.
70 That metadata will be run through an internal whitelist, and any data
71 whose “key” is not found on the whitelist will be automatically selected
72 for deletion.</p>
73 <p>If you disagree with ExifWasher’s decisions, you can check or uncheck the
74 boxes next to the metadata in question. When you are satisfied with the
75 choice of metadata to be scrubbed, click “Wash” and all offending metadata
76 will be removed. A dialog will pop up showing the metadata remaining in
77 the new, washed file.</p>
78 <h2>Output Files</h2>
79 <p>ExifWasher never modifies an existing image file. Instead, it creates a
80 new file of the same type but with “_washed” appended to its name. For
81 example, processing <code>foo.jpg</code> will create <code>foo_washed.jpg</code>.
82 By default, the new file will be created in the same directory as the file
83 being washed.</p>
84 <h2>ExifWasher is Configurable</h2>
85 <p>Both the whitelist and the destination directory for the washed files are
86 user-configurable in the Preferences menu.</p>
87 <h3>Configuring the Whitelist</h3>
88 <p>There are two kinds of whitelist entries: those that match an entire
89 metadata key, and those that match a key prefix. The latter end in an
90 asterisk. The whitelist is case-sensitive; i.e. the entry <code>exif.image.colormap</code>
91 <em>will not</em> match the <code>Exif.Image.ColorMap</code> key.</p>
92 </body>
93 </html>