- Drag and Drop
- Known Problems
- Adding JAR Files
- Running from the Command Line
- About the Icon
InstallationDownload ImageJ for Mac OS X from the Download page. The ZIP file you download (Image1.xx.zip) should automatically expand to a folder named "ImageJ". Copy this folder to the Applications folder, open it, and copy ImageJ.app to the dock. A 32-bit version of ImageJ (ImageJ32.app), needed for running QuickTime plugins, is also available, but it is unabe to use more than 1800MB of memory.
With OS X 10.7 or later, the first time you run ImageJ, you may get get an "ImageJ can't be opened because it is from an unidentified developer" message, which can usually be bypassed by right clicking on ImageJ.app and selecting "Open" from the drop down menu. if that doesn't work, open the "Security & Privacy" panel in System Preferences and change "Allow apps downloaded from:" to "Anywhere". You can switch back to the original setting once ImageJ is running.
OS X 10.10 (Yosemite) and later do not include key files required for running commands like File>Import>Using QuickTime and File>Save As>QuickTime Movie that use QuickTime for Java. You can work around this problem by copying the files QTJava.zip and libQTJNative.jnilib, available at imagej.nih.gov/ij/download/qt/ into ~/Library/Java/Extensions, where "~" is your home directory. Yosemite hides the Library folder by default, so you will need to open your home folder and check "Show Library Folder" in the View>Show View Options dialog. Before copying the files, you will need to create the ~/Library/Java and ~/Library/Java/Extensions folders.
macOS 10.12 (Sierra) introduces a security feature called Path Randomization that can cause ImageJ to not work as expected. Path randomization is in effect if the "ImageJ home" path shown in the Image>Show Info window starts with "/private" and plugins are not installed in the Plugins menu. You can disable path randomization by moving ImageJ.app out of the ImageJ folder and then copying it back. If the ImageJ folder is in /Applications you will need to hold down the alt key while dragging ImageJ.app out of the ImageJ folder.
macOS 10.13 (High Sierra) breaks Java 6, making it impossible to enter text into ImageJ dialog boxes. To work around this problem, use the version of ImageJ bundled with Java 8, available from the download page. High Sierra also has the path randomization problem.
MemoryUse the Edit>Options>Memory & Threads command to make more than default 3000MB of memory available to ImageJ. Note that setting the "Maximum Memory" value to more than about 75% of real RAM may result in poor perfomance due to virtual memory "thrashing". The maximum amount of memory that can be allocated on 32-bit systems is about 1.8GB. Another way to make more memory available to ImageJ is by running from the command line and using the -Xmx option.
The Edit>Options>Memory command updates the VMOptions key in the Contents/Info.plist XML file in the ImageJ.app bundle.You will get an error message if you do not have write permission for the ImageJ application. To check and/or change the permissions, open the ImageJ folder, select the ImageJ application, and use the Finder's File>Get Info command.<key>VMOptions</key> <string>-Xms256m -Xmx3000m</string>
UpgradingUse the Help>Update ImageJ command to upgrade to the latest version of ImageJ. This command may fail with a "Release Notes are not in the expected format" error if you are running a version of ImageJ earlier than 1.50i. You can work around this problem by using the ImageJ Updater plugin to upgrade.
Drag and DropThe OS X version of ImageJ opens images, text files, ROIs and LUTs that are dropped on the ImageJ icon or on the "ImageJ" window. Drag and drop TIFF files on the >> icon in the toolbar to open them as virtual stacks.
- The first time you run ImageJ you may get a "ImageJ can't be opened because it is from an unidentified developer" message.
- Plugins may not be installed when running macOS 10.12 (Sierra) due to Gateway Path Randomization.
- Text cannot be entered into dialog boxes on macOS 10.13 (High Sierra) when ImageJ is using Java 6 .
- Commands (e.g. File>Import>Video) and plugins that use QuickTime for Java fail with 64-bit versions of Java and with OS X 10.10 (Yosemite) and later .
- Using command-v to paste text into the file name field of Save As dialog boxes does not work. This is a bug in the Java FileDialog class that can worked around by right-clicking in the name field and selecting "Paste" from the drop down menu.
or, with the version bundled with Java 8, type:java -jar -Xmx1024m ImageJ.app/Contents/Resources/Java/ij.jar
The -Xmx1024m switch specifies that ImageJ will have available a maximum of 1024MB (1GB) of RAM.java -jar -Xmx1024m ImageJ.app/Resources/Java/ij.jar
Use a command like this to run ImageJ from any directory:
ImageJ recognizes the following command line options:java -Xmx1024m -jar /Applications/ImageJ/ImageJ.app/Contents/Resources/Java/ij.jar -ijpath /Applications/ImageJ
Specifies the port ImageJ uses to determine if another instance is running Example 1: -port1 (use default port address + 1) Example 2: -port2 (use default port address + 2) Example 3: -port0 (don't check for another instance) -debug Runs ImageJ in debug mode