JPEGS in vs JPEGS out of PP

  • Thread starter Thread starter val
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V

val

When you save a powerpoint slide as a JPEG, it frequently
comes out much smaller than the image that went in. Does
this mean that PP is compressing it in the way out, or
does PP take big images, make them smaller and project
them that way.

In other words if you import a 350 K jpeg into PP and get
a 55 K image when you save the slide as a JPEG, is what
you're seeing projected a 55K image or a 350 K image

Val
 
In other words if you import a 350 K jpeg into PP and get
a 55 K image when you save the slide as a JPEG, is what
you're seeing projected a 55K image or a 350 K image
Click to expand...

What you see projected when viewing a PPT presentation is the image you
brought in originally, but downsampled. For example, suppose you pull in a
1024 x 768 image and reduce it on the slide to 1/4 frame. When PPT displays
it on a 1024x768 monitor it has to sample the image down to 1/4 of that, so
you SEE a smaller image.

The full image is still in the PPT file, and when you resize the picture,
PPT downsamples or upsamples again from the original data.

Now, suppose you take that same slide and save as JPG.
PPT exports at 72 dpi and your slide's probably 10" or so wide, so you get a
720 x whatever JPG image with your picture ( 1/4 frame, taking up half the
width, remember) bumped down to half of 720 or 360 pixels.

If you export at a much higher resolution by various hooks 'n crooks, you
can get the image up to something like what it was to start with.
 
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