Compress Pictures
I thought it might make some sense to introduce some of the new things that we’re doing with picture handling in Office2007. Given that Pictures are found in over 57% of all office documents, it’s our single biggest graphic type and deserves some special attention.
One of the best features for managing pictures in Office2003 is the feature that you never knew about; Compress Pictures. We did such a good job of hiding this in a remote part of the obscure Picture Toolbar, that we all but assured that only the highest of the power user ever found it. We fixed this for Office2007. Not only is it clearly displayed in the Picture Ribbon, but parts of this feature work automatically to help you manage pictures and file sizes in your presentation. With new generations of digital cameras increasing the megapixel count into the double digits, insertion of huge images is becoming a serious problem for keeping presentations manageable.
Insert a picture in PowerPoint2007 and the picture will be resized down (if required) in order to fit on the slide. The Picture Tools Format Ribbon will display automatically.
Let’s click on Compress Pictures and see what’s new.
Pressing OK will automatically run a basic picture compression on all of the images in the presentation. The big thing that is happening is the image is being resized downwards. By default, it is set to 220 pixels per inch (ppi). We look at the size of the image on the presentation and size it accordingly downwards. 220 is good high end and conservative number, it will ensure that even a full sized image, spanning the entire presentation, will print out at photographic quality when output full size to a photo quality printer. You would be hard-pressed to see any differences between this size and an image with a larger ppi.
Let’s take look at the Options dialog.
Here is where some of the new improvements are exposed. By default, Office will automatically apply this resizing behavior on save, so you won’t even have to go to this dialog in order have compress pictures running. In addition to resizing the pictures, any cropping will also be deleted in order to save space.
We also provide three sizes for the resize, tailored for Print, Screen and E-mail sizes. If you really want to take fine control over your pictures sizes, then you can turn off the Automatic compression on Save, target a specific smaller size and use the Apply to selected pictures only checkbox on the main dialog. Just decide how much space you want to save, how much quality you are willing to lose and what the target of your presentation is. Just remember, once you compress and save, you can’t get back to the original size,
Seeing is believing
So how do we know what’s really happening to all the images in your presentation? You could save the file and look at the resulting file size, and try to deduce what happened, but there is a far better way in Office2007. We can extract and look at the actual images that are being saved in the file.
Let’s try this. Open up a blank presentation and insert a single large image into the presentation. I used a 420K JPEG file that was sized to 300ppi and had a total resolution of 2439 pixels by 3000 pixels. Much more data that we need in order to get a good quality printout.
Now save the presentation in the new PowerPoint2007 PPTX file format. The PPTX is just a container that uses the standard ZIP compression method.
Navigate with Windows Explorer to the presentation and change the extension from .PPTX to .ZIP. You can now open the presentation in explorer and take a look at the files inside.
Navigate to the ppt folder, then the media folder, and you will see a list of images that are included in the presentation. Note, PowerPoint did not maintain the original file name, so you’ll have to dig through the files if you have many of them. In this example, I had just one single picture and PowerPoint called image1.jpg.
You can now drag the file out to the desktop, open it, examine it and see exactly what happened to the image in your presentation. Getting direct access to the images stored in the file has many other useful benefits and possibilities.
Mark Jaremko
