No, it is not possible with Zenphoto at all to write meta data to images itself. One of the supported graphics libs does not even support metadata.
You have to add metadata with external tools to the images itself. Since Zenphoto is file system based you could re-upload the images with same names to the same albums again.
Another way is using the XMP plugin and a so called sidecar file with the XMP metadata.
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No, it is not possible with Zenphoto at all to write meta data to images itself. One of the supported graphics libs does not even support metadata.
You have to add metadata with external tools to the images itself. Since Zenphoto is file system based you could re-upload the images with same names to the same albums again.
Another way is using the XMP plugin and a so called sidecar file with the XMP metadata.