iFDO content fields#
The iFDO content is one section of the complete iFDO file. See its description to learn about its file formats, parts and sections. All fields in this section are optional!
Motivation#
Image data is inherently unstructured and obtaining a glimpse of its content is hard to achieve for humans as well as machines. The iFDOs content fields are a mechanism to encode the content of image data by means of visual, textual or other data proxies (annotations, previews, descriptions, categorisations, etc.). These can take various forms as described below. Simple examples of visual proxies are thumbnails for images or the average intensity along a video.
File format#
All iFDO content fields shall be stored alongside the core metadata in your iFDO file! It does not take up a specific section of the file, rather the values are intermixed into the image-set-header and image-set-items section!
Domain-specific iFDO content fields#
| Field | Type | Description |
|---|---|---|
| image-entropy | number | Information content of an image / frame according to Shannon entropy. |
| image-particle-count | integer | Counts of single particles/objects in an image / frame |
| image-average-color | array | The average colour for each image / frame and the n channels of an image (e.g. 3 for RGB) |
| image-mpeg7-colorlayout | array | An nD feature vector per image / frame of varying dimensionality according to the chosen descriptor settings. |
| image-mpeg7-colorstatistic | array | An nD feature vector per image / frame of varying dimensionality according to the chosen descriptor settings. |
| image-mpeg7-colorstructure | array | An nD feature vector per image / frame of varying dimensionality according to the chosen descriptor settings. |
| image-mpeg7-dominantcolor | array | An nD feature vector per image / frame of varying dimensionality according to the chosen descriptor settings. |
| image-mpeg7-edgehistogram | array | An nD feature vector per image / frame of varying dimensionality according to the chosen descriptor settings. |
| image-mpeg7-homogeneoustexture | array | An nD feature vector per image / frame of varying dimensionality according to the chosen descriptor settings. |
| image-mpeg7-scalablecolor | array | An nD feature vector per image / frame of varying dimensionality according to the chosen descriptor settings. |
| image-annotation-labels | array | All the labels used in the image-annotations. Specified by an id (e.g. AphiaID), a human-readable name and an optional description. |
| image-annotation-creators | array | All the annotators that created image-annotations. Specified by an id (e.g. ORCID), a human-readable name and an optional type specifying the annotator’s expertise. |
| image-annotations | array | This field stores all annotations as a list of dictionaries of 3-4 fields: shape, coordinates, labels and (optional) frames. See further explanations below. The list of labels specifies the IDs or names of objects and annotators and their confidence. These should be specified in an image-annotation-labels and image-annotation-creators field (see above) to provide more information on the values used in these fields. |