Re: Extensible Persistent Properties for ImageJ Images

Posted by Michael Schmid on
URL: http://imagej.273.s1.nabble.com/Extensible-Persistent-Properties-for-ImageJ-Images-tp5023228p5023229.html

Hi Michael

maybe an incomplete answer, but better than no answer:

- I guess that the 'info' String will remain there for as long as we
have ImageJ.
- At least in ImageJ1, I am not aware of any convention to avoid
duplicate keywords.
- The reason why other ImagePlus properties are not saved is probably
that (i) the lack of a mechanism to save and read them (they can be any
type of object; java serialization would not guarantee that they can be
read at a later stage when the code of the class changes) and (ii) one
might store objects for temporary use in the properties.


Michael
________________________________________________________________
On 15.04.20 15:58, Michael Ellis wrote:

> I’m using ImageJ 1.52 as a Java library. for my own Java application.
>
> I create images that are to be saved and restored. I want to attach extra information to an ImagePlus that will be persisted and restored using the standard ImageJ open and save operations.
>
> I’ve discovered that only some specific ImagePlus  properties are persisted with the default ImageJ file operations (such as  the “Info” property)
>
> The “Info”, appears itself to be a string formatted in a manor that is itself a list of properties. Can I safely append more (sub) properties to this “Info” property and expect them to be safel honoured by future versions of ImageJ 1.xx?
> The code below does what I want, but is it future safe?
> Also why are not all ImagePlus properties persisted?
> Is there some other mechanism for save augmenting an Image in ImageJ with extensible metadata that I am missing?
> I intend to add my extra properties with a reverse domain name notation key to avoid accidental clashes.
>
>      /**
>       * Adds a key-value pair to this ImagePlus's Info properties. The key is
>       * removed from the properties table if value is null.
>       *
>       * @param imagePlus
>       * @param key
>       * @param value
>       * @throws IOException
>       * @see #getInfoProperties
>       */
>      void setInfoProperty(ImagePlus imagePlus, String key, String value) throws IOException {
>          Properties infoProperties = getInfoProperties(imagePlus);
>          if (value == null) {
>              infoProperties.remove(key);
>          } else {
>              infoProperties.setProperty(key, value);
>          }
>          StringWriter sw = new StringWriter();
>          infoProperties.store(sw, null);
>          imagePlus.setProperty("Info", sw.toString());
>      }
>
>      /**
>       * Get a property from an ImagePlus's Info properties.
>       *
>       * @param imagePlus
>       * @param key
>       * @return the
>       * @see #getInfoProperties
>       */
>      String getInfoProperty(ImagePlus imagePlus, String key) throws IOException {
>          return getInfoProperties(imagePlus).getProperty(key);
>      }
>
>      /**
>       * Get the specified ImagePlus's Info properties. The "Info" properties are
>       * a list of properties nested within the ImagePlus's property indexed with
>       * the key value "Info". ImagePlus's "Info" property is saved and restored
>       * by the default ImagePlus save and open operations.
>       *
>       * @param imagePlus
>       * @param key
>       * @return the
>       */
>      Properties getInfoProperties(ImagePlus imagePlus) throws IOException {
>          Properties infoProps = new Properties();
>          infoProps.load(new StringReader((String) imagePlus.getProperty("Info")));
>          return infoProps;
>      }
>
> Michael Ellis (Managing Director)
> Digital Scientific UK Ltd.
> http://www.dsuk.biz <http://www.dsuk.biz/>
> [hidden email]
> tel: [phone]
>
> The Commercial Centre
> 6 Green End
> Cambridge
> CB23 7DY
>
> === END OF EMAIL ===
>
>
> --
> ImageJ mailing list: http://imagej.nih.gov/ij/list.html
>

--
ImageJ mailing list: http://imagej.nih.gov/ij/list.html