Photographs and Bloating

[Guest]

I have been aware of the bloating issue in Access for a couple years and have
experimented some with a couple implementations. Images in my application
grow when they are inserted in my application but the amount is not same (15x
to 28x; two tests) for each image.

I also found that the images that I insert from my database into Word are
better quality than those that I insert from the server -- same image.

Is the reason for this related to jpeg compression? Does Access uncompress
the files? I ask because I worked briefly for ER Mapper and their ECW
compression software uncompressed images when they were printed. The images
were small on the server but the host application returned them to the normal
size for printing, which restores the quality and is important to me.

Any explanation of what Access does will be appreciated.

 

[(PeteCresswell)]

Per roccogrand:

I also found that the images that I insert from my database into Word are
better quality than those that I insert from the server -- same image.

Is the reason for this related to jpeg compression? Does Access uncompress
the files? I ask because I worked briefly for ER Mapper and their ECW

I don't know much about images in general, but I have noticed from
experimentation that MS Apps seem to prefer .BMPs over .JPEGs.

Can't recall the numbers, but the size diff for two MS Word docs loaded with the
same image, but .BMP in one and .JPG in the other was ludicrous.... the .BMP doc
being much, much smaller.

My guess would be that MS does some compression magic with .BMPs that it doesn't
do (or messes up...) with JPEGs.

 

[Larry Linson]

The problem of bloating with OLE fields and Bound OLE Frames is discussed in
the article included with the Imaging Examples at
http://accdevel.tripod.com.

Access, utilizing the registered COM-enabled software that processes JPG on
the user's system, creates a .BMP "thumbnail" that it stores in the OLE
field. Even the "thumbnail" sized BMP is always significantly larger than
the original JPG. It may pay to use a different approach instead of OLE...

Larry Linson
Microsoft Access MVP