When you open Image Comparer™ you will see an application
window that looks something like what you see below. The area
covering 2/3 of the left portion of the window contains the results of your
image comparison analysis (initially this will be blank). The right 1/3
of your screen contains the controls for Image Comparer™. These
controls are our focus in this part of the tutorial.
There are three fundamental steps taken in using
Image Comparer™ :
Select the image files of interest.
Perform your image comparison analysis which creates a
database reflecting the analysis results.
Manipulate your image file collection (move, copy and/or
delete files) based on the results of the image comparison analysis.
To select the image files of interest you use the
"Compare folders" and "Compare groups" buttons.
Use "Compare folders" when you want
all of the image files contained within the specified folder(s) to be compared
against all of the other files in the same folder(s). Use "Compare groups"
when you only want to compare the files in one folder (or set of folders)
against the files in another folder (or set of folders). The key
distinction is that "Compare groups" does not
compare the files within a folder against the other files within that same
folder, while "Compare folders" does. Tip:
Use "Compare groups" whenever possible to improve
the simplest case you may have a collection of image files in a folder and you
want to compare all of these image files against all of the other image
files in this folder. In that case you would want to use "Compare
folders". When you select this button a dialog box looking
something like this pops up which enables you to build a list of the folders
The "Add folder", "Delete folder" and
"Clean list" buttons are your key tools in building a list of
"Add folder" brings up a standard file browser dialog
box. Once you have selected a folder (or set of folders) your
"Compare folders" dialog will be updated with the selected
The checkbox to the left of the selected folder controls how
the folder should be handled as described in the legend at the top of the
The default is to not include subfolders. This means
that if there are any subfolders within the specified folder the subfolders
will not be examined and image files contained in them will not be included in
||You can remove folders from the list by selecting them and
then selecting the "Delete folder" button.
||All folders can be removed from the list by selecting the
"Clean list" button.
The drop-down selector whose default selection displays
"All supported files" allows you to restrict the analysis to a
particular type of image file format (e.g. JPG, BMP, TIF).
The "Database limit" defines how much information
from the analysis is to be stored in the database. The value of the
database limit indicates
the minimum value % similarity to be stored in the database. In the screenshot
above the value is "99". So only files whose similarity are
99% or greater will be stored in the database. This is an important
control for improving performance for large collections of image files. Tip:
Set this value as high as you can for your analysis purposes to keep your
database size small and your performance high.
The "speed /
quality" slider allows you to make a trade-off between accuracy and speed
in the comparison analysis. If you place the slider more toward the
"speed" side you will find that the analysis runs a little faster,
but that the similarity assessment will be less accurate.
Conversely, if you move the slider more toward the "quality" side
your analysis will take longer but the similarity assessment will be more
accurate. The performance benefits will generally only be
noticable on very large databases and/or on less capable computer systems, so
.... Tip: Unless you are terribly sensitive to performance leave the
slider at the default position (shown above).
When you have finishing selecting the folder(s) of interest
you'll proceed to the next step by selecting the "Compare"
You will then be taken to a "Creating database"
dialog box. By default your database files are created in the Image
Comparer program directory's DataBases folder. If this is the
first time you've created a database for this collection enter a meaningful
name (overwriting "New Folder") and select the "Create
folder" button. If you are regenerating a database you can merely
select the appropriate database folder from the file browser window.
Once you have selected the appropriate database folder you should select the
"Create database" button to begin the analysis and create the
A progress indicator will give you feedback on the program's
progress in analyzing your collection of image files. Upon
completion your database results will be summarized in the left-hand 2/3 of
the program's main window -- your database viewer.
At this point you have completed the first two steps in using Image
Comparer™: 1) selecting the images of interest and 2) performing the
analysis to create the database. Now you will want to consider the
results and modify your collection of image files based on what you've
It is probably worth noting at this point that your database
for this analysis has been saved in the database file you specified. So
if you wanted you could exit Image Comparer™ at this point and when you
return later the database you last had open will be automatically
re-opened. Tip: Since Image Comparer™ does not have an
explicit "Save Database" function you may want to exit and re-enter
the program just to ensure that your database is safely saved.
Let's take a tour of the database viewer portion of the main
Image Comparer™ window. The purpose of this part of the main window is
to give you a view into the database you have created.
The bottom portion of the database viewer (shown below) is a
record browser which allows you to review and select records and files within
records of the database. The selected record is highlighted.
The currently selected record's information is shown in the
upper portion of the database viewer (shown below).
The files compared in the database record are referred to as
"File N1" (on the left) and "File N2" (on the
right). A thumbnail of each image file is displayed. (The
"smoothing" drop-down is an advanced control enabling you to select
the method by which the thumbnail is created. It impacts the quality of
the thumbnail image. It has no impact on your images or on the
comparisons made during the analyses. In general, unless you have a "golden
eye" you can't tell the difference and all of the methods other than
"<None>" will negatively impact the performance of your
database viewing experience. Tip: Leave the
"smoothing" set to "<None>".).
For image pairs which are not identical (i.e., similarity <
100%) the "quality" assessment at the top between the thumbnail
pictures will indicate (by pointing to it) which image is of higher
quality. "Higher quality" is defined as the image of higher
resolution (generally the bigger image file). Your own review of the
resolution and file size information below the thumbnail picture would quickly
verify that. The information below the image also indicates the
file format (e.g., JPEG, TIFF, BMP, GIF). The very bottom of this upper
portion of the database viewer provides you with the complete file path
information for each file.
The record browser portion of the database viewer (see below)
contains check boxes on each side where you can select "File N1"
and/or "File N2". When you select a file the status
information at the bottom of the record browser indicates how much disk space
would be freed up if you chose to delete all of these files.
Before moving on to actually deleting, copying or moving your
files let's look at one further way you can optimize your database viewing and
manipulation experience by limiting the number and nature of the records you
are dealing with in the database. You will recall that when you
created the database you were allowed to define a "database
limit". In our example we limited the database creation to include
only records with similarity of 99% or greater. As you can see in
the record viewer above there are records with similarities of both 99% and
100% (the higher percentage similarities listed at the top).
You can further limit what you are viewing of the database by controlling the
"% Similarity" on the top-right portion of the main Image
If we would change the range to be from 100% to 100% we would
exclude from consideration (and not see) the records of 99% similarity.
Likewise if we adjusted the "% Similarity" to view to be 99% to 99%
we would no longer see the 100% similarity records. They would still
exist in the database, we just wouldn't have to deal with them at this
time. This is done prior to selecting any records/files by modifying the
values in the "% Similarity" control panel and then selecting the
You'll notice that once you've selected a file/record the
"Adjustment" button is disabled (dimmed out).
Tip: When dealing with large databases limit your
"% Similarity" to improve the performance of your database viewing
Another convenient control that can be utilized prior to
selecting any files/records is the "Mark by quality"
Selecting this button will cause the file of the lower quality
to be marked for all of the available records. Tip: A
cautionary note here -- it is advisable to review the selections for your set
of images to see if the selection is appropriate for you, especially if your
subsequent action would be to delete the selected/marked files.
You will notice that as soon as any file/record is selected
the "Mark by quality" button turns into the "Remove all
And, as the name implies, selecting the "Remove all
marks" button will cause all
marks to be removed/cleared.
After any file/record has been marked the following operation
can be performed on the files (or records): "Copy files", "Move
files", "Delete files" and "Delete records".
The buttons shown below initiate these operations. Until a file/record
is marked these buttons are disables (dimmed as shown on the right
"Copy files" and "Move files" both bring
up a "Select folder" dialog browser which contains a standard
file/folder browser. Once you have selected your target file and hit the
"Ok" button in the "Select folder" dialog your marked
files will be copied/moved as you have requested. In the case of
"Move files" the database must be adjusted to account for the
absence of the marked files in their old location.
"Delete files" will, as the name implies, delete all
of the marked files and then adjust the database to account for the absence of
the marked/deleted files. Note that the checkbox in the upper-right
corner of the "Delete files" button is an active control. When
checked (the default) the files that are deleted are sent to your Recycle Bin
(and hence recoverable until you empty your Recycle Bin. When not
check the files are permanently deleted.
"Delete records" only affects the database record
and does not affect the files contained in the record. If you select
"Delete records" the database record containing marked files will be
removed from your database. This is convenient when dealing with large
databases and you have database entries for which you do not wish to otherwise
delete, copy or move the files it has identified. It helps remove
clutter in your database and simplify your database review.
bottom right portion of the main Image Comparer™ window are a collection of control / information functions.
"skins" button is used to select from a collection of
"skins" or color schemes for the Image Comparer™ user
interface. Selecting the "skins" button brings up a file
browser dialog defaulting to the location of the skins provided with the Image
Comparer™. Clicking on one of the files on the left hand browser pane
causes a preview of the "skin" in the preview pane at the
right. Selecting no file causes your default Windows color scheme to be
the "About" button provides you information on the program including
version information, license information and useful web links.
"Open database" button enables you to open previously created /
manipulated databases enabling you to overlap your work on multiple Image
Comparer™ projects. Selecting the "Open database" button
brings up a standard file/folder browser dialog defaulting to the location
where Image Comparer™ stores its databases. You can then navigate to
the database of your choice. Selecting the down-arrow button on the far
right of the "Open database" button pops up a list of the most
recently used Image Comparer™ from which you can select.
Selecting the "Exit" button is the preferred method of terminating
your work with the Image Comparer™ program.