Taken from http://office.microsoft.com/en-us/access-help/store-images-in-a-database-HP005280225.aspx
..."However, embedding images can rapidly inflate the size of your
database and cause it to run slowly. This is especially true if you
store GIF and JPEG files, because OLE creates additional bitmap files
that contain display information for each of your image files, and
those additional files can be larger than your original images. In
addition, this method only supports the Windows Bitmap (.bmp) and
Device Independent Bitmap (.dib) graphic file formats. If you want to
display other common types of image files, such as GIF and JPEG
images, you have to install additional software."...
To explain how these bitmap files are stored, the link below offers more explanation than the microsoft site:
Taken from http://www.ammara.com/support/kb/showkbe5cc.html
..."OLE Linking & Embedding is a technique used by Microsoft Access to
store 'Objects' in database tables.The technique relies on the
associated external application to store, present and edit the data.
In some cases an additional uncompressed 'preview' image is also saved
in the table (even when linking). This preview image is used for
faster display of the data, or when the server application isn't
available. This can cause a massive overhead. If you're storing jpeg
images the uncompressed preview can be ten or twenty times the actual
image size, causing the size of the database to rocket."...
So, when you drop an image onto a form in MS Access, uncompressed image data is saved to the system tables. This is actual uncompressed table data, so a compact and repair may offer little help.
The common workaround seems to be store the path to the image in a database table, and use that path to invoke the image on the form.
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