Inserting Pictures into Excel File causing huge increase in file size

[ecuevas]

Hi, we're working with a file in Excel where we are having people insert pictures into the spreadsheet. The spreadsheet with no pictures is 2.3 MB. The picture is 730 KB. But when it is inserted into the worksheet the file becomes 24 MB. If I add the picture again it goes up to 45.8 MB. We used the compress picture option in the toolbar but that only took it down to 23.9 MB for a file with a single picture. We need to E-Mail the worksheet but we can't E-Mail anything larger than 22 MB. Why is it doing this and how can we make the file smaller?

 

[boblarson]

I know that if you use the .png (Portable Network Graphics) format, it will reduce the size drastically.

 

[ecuevas]

We have a button that prompts you for a picture. The picture is then added to a box and resized to fit the box. It won't allow us to enter a .png file.

 

[unmarkedhelicopter]

I believe that whatever picture you add to an Excel File (or Word Doc for that matter) it is stored as the same internal format (unfortunately it's a .bmp i.e. uncompressed).
This is a common mistake with people with fancy cameras, they think (because they can) they should insert a 10M pixel image, this is rarely the case. Think about it, if your image is part of a report and you print it off and the image is 2 inches by 3 inches then even at 300 dpi (what ALL commercial photo printing labs print at) you'd only need 600 x 900 pixels i.e. 1/5 MP not 10 MP. So reducing the image size should be your first step, your second should be as bob suggests to use the best compression you can for the image as despite what I said earlier the document also stores the original (more file bloat), then as you say use the compress ALL images option (though if you've done as I've said you probably won't get much out of this).
If you DO NEED to include 10MP images then you are doing things wrong.
What you'd need to do is employ a developer to write something that will open the 10MP image (that was sent with the file, but not in it) in either a common desktop app or in a form to display the picture.

Edit : I often cheat and instead of using 300dpi images I'll use 150dpi and thus quarter the file size.

 

[ecuevas]

I figured out a solution to my problem. I just used the insert picture button from the picture toolbar instead of using the button that I made. This brings down the size to about 3 MB. The problem I have now is that I have to resize the image manually. Is there a way to make the image change to a certain size automatically when it opens?

 

[boblarson]

I believe that whatever picture you add to an Excel File (or Word Doc for that matter) it is stored as the same internal format (unfortunately it's a .bmp i.e. uncompressed).

I'm not convinced about that because of specific experiences I've had. When I started my last job there was a manual that several people had created using screenshots. They would do the typical, "hit the PrtScn button" and then paste into the document. Now, THAT is definitely using the largest size possible. Then, if I created png files of those same screenshots before inserting, the size would be many, many Kilobytes less.

You can run a quick test, too. Take a bmp file and convert it to png. Then, open a new .doc file and insert one of the pics into it and save it. Then, create another new .doc file and insert the other one and save it. Check the file sizes. I just did the same test with a 6"x3" screen capture saved from SnagIt and saved the same pic as two different types and then inserted each into a separate document. Just with one pic there was 4Kb difference.

The interesting thing is that the Word documents that I inserted the pics in were:

53 KB - with BMP
47 KB - with PNG

And the original sizes of the image files before inserting were:
BMP - 947 KB
PNG - 30 KB

So Word is doing something to it as well when you use the Insert > Picture > From File to compress it as well.

 

[unmarkedhelicopter]

Hmm
That's interesting ... I'd like to do a full series of experiments but ... the time it would take ... Does anyone want to volunteer ?

 

[hotwire]

Hello, I know this is a very old thread but I came across it by searching for an answer to MS Excel flaw on enlarging a file on a single image..

It appears that this forum is more dedicated to MS Access, however, It's the closest I have come after doing searches for this issue with excel file size increasing with images..

I have a similar situation, but what blows my mind is that I am only using ONE image as a background but every time a new sheet is created (With The Same Image Reference), Excel continues to make the file larger although each sheet is referencing the same image file! This Is crazy.. And I can't seem to find a good solution to this flaw as to why each sheet makes the file larger although they reference the same image path? To me this should be an Excel Bug or flaw. :banghead:

Thanks for any info regarding this issue.

PS. The only workaround I have used is to have each sheet vba access the image path for the background.. This jeeps the file size only as large as the image size plus any additional data the user adds.

hotwire