Image Reader

This Node Is Deprecated — This version of the node has been replaced with a new and improved version. The old version is kept for backwards-compatibility, but for all new workflows we suggest to use the version linked below.
Go to Suggested ReplacementImage Reader

Reads images from various file formats supported by the Bio-Formats library and imports them to the KNIME-internal image format. A list of the supported formats can be found here: Image can also be downloaded and read from URLs (e.g. http://...). The URLs have to be provided via the input table (as strings).


File browser
Choose your image files here and add them to the list of selected files. An image preview is available which will also help you to determine, whether an image format is supported or not. The list of the core meta data gives you some more information about the image object.

Additional Options

Append additional OME-XML-metadata column
You can add a column containing the metadata formated as an OME-XML-String (more details on ).
Image Factory
Defines the way how the images are created and therewith kept in memory: Array Image Factory (stored as ONE array; pros: fast pixel access; cons: limited number of pixels per image), Planar Image Factory (each plane is stored in an array; pros: images are read faster; cons: limited number of pixels in an XY-plane, slower pixel access), and Cell Image Factory (multiple arrays of fixed sizes are used, pros: unlimited number of pixels per images; cons: very slow pixel reading and pixel access))
Use complete file path as row key
If checked, the complete file path will be used as row key, else only the file name. Has no effect, if images are read from URLs.
Check file format for each file
Checks for each file individually the file-format, if checked. Else, the file format as assumed to be the same for all files and only if the reading fails, the new file format will be determined.
File name column in optional table
If another node with a string column is plugged to the optional in-port, the column, which contains the potential file paths, can be selected.
Read all series
Some image file formats might contain multiple images (called series). One can either read all available series (each appended as own table row) or just one series with the specified index ("Series index").
Load group files
If selected, related group files will be read as well.

Subset Selection

Image Subset Selection
Select the image planes here you actually want to open. Use shift or ctrl-keys to mark more than one plane or the "all"-checkbox to select all available planes. Detailed informations about the sizes of the individual dimensions can be obtained from the image metadata.

Alternatively, selecting subsets can be done in three ways using the text field below each selection list:

Discrete Element Selection Every element that shall be selected can be entered on it's own, separated by commas. e.g. "1, 5, 8, 9"

Cohesive Element Selection Selecting a complete region "from" a given value "to" another can be done by putting a hyphen between two values, marking the first as the region start and the second as the end. Comma-separation still holds and can separate either complete regions, or regions and discrete selections. e.g. 1-5, 8-10, 11

Function Based Selection Selection values based on a given function can be done by marking the function with a leading "f=" and entering the desired functionality thereafter. Any single variable function or constant contained within the javascript math package can be used with standard javascript syntax. (e.g. math.pow(2, i) for selecting 2, 4, 8,...)

Combining The above mentioned functionalities can be arbitrarily intermingled as every comma separated entry is read and interpreted on it's own. e.g. Selecting all Values from 1-10, every eleventh entry and the twentieth entry for some reason can be done by entering: "1-10, 20, f=11*i"

Input Ports

Optional input table with a column containing the file names/paths.

Output Ports

The opened images and optionally a column with the metadata.


Image Viewer
Displays the selected cells with their associated viewer if it exists.




You want to see the source code for this node? Click the following button and we’ll use our super-powers to find it for you.