What can we do if the generated thumbnails are unsatisfactory?
The underlying image software that Asset Bank uses
(ImageMagick) to convert from one image format to another works extremely well
for ‘open‘ formats such as JPEG, JPEG2000, TIFF, PNG, GIF, etc. Also, it
usually works well when converting proprietary formats such as EPS, PSD, etc.
However, on occasion, conversions from some propretary formats are
unsatisfactory - this is more likely if the images are complex, for example
contain layers, or were created using unusual colorspaces that are not embedded
in the images.
To get round this Asset Bank includes functionality that
enables admin users to upload a ‘working file‘ representation of the image,
which is then used by Asset Bank instead of the source file. For example, you
could create a JPEG version of a problem image in Photoshop and then upload
that, along with the source file for the problem image, as the ‘working file‘.
As this working file will also be used on download to create different versions
of the image it is important to use a working file of sufficient resolution -
we recommend it is the same pixels dimensions as the source.
To enable this functionality, set the application setting
‘allow-image-substitutes‘ (in ApplicationSettings.properties) to true, i.e.:
allow-image-substitutes=true
Once enabled, you can upload a ‘working file‘ (e.g. a JPEG)
for an existing image asset by clicking the ‘Edit‘ button and then browsing for
the file in the field labelled ‘Working File‘.
To add a working file for an image during a ‘bulk upload‘,
simply give the working file the same name as the source file it represents
(but keep the JPG extension), and prefix it with an underscore character. Then,
ensure that the working file is uploaded to your ‘bulk upload‘ directory along
with the source file.