If you have ever renamed a PowerPoint (PPTX) file extension to .zip and opened it up to look in the media subfolder, you might have seen files like hdphoto1.wdp in there alongside JPEGs, PNGs and more familiar media files:
So what are WDP files?
They are a highly compressed image format developed by Microsoft, called by many names: Windows Media Photo, HD Photo and also JPEG XR. These files are similar to JPEG, but will compress much smaller than equivalent JPEGs.
More importantly perhaps, why are they appearing in your PowerPoint file?
When you adjust certain picture settings in PowerPoint, it converts your original image into a WDP file. This WDP file becomes the 'original version' without any effects applied. PowerPoint then creates a PNG of your image with the effects applied for backward compatibility.
PowerPoint uses the hidden WDP file to allow you to revert or modify the effects at any point. Whenever you change the effects, it regenerates the PNG.
Which picture settings trigger WDP files?
WDP files aren't just created by complex filters. Adjusting basic lighting or color settings will also trigger this dual-image bloat. Features that cause WDP generation include:
Artistic Effects: All 23 presets (Blur, Film Grain, Glow Edges, etc.)
Picture Corrections: Adjusting Sharpen, Soften, Brightness, or Contrast.
Picture Color: Adjusting Color Tone, Temperature, or Saturation.
Sometimes, tweaking these settings will massively increase the size of your presentation because PowerPoint creates a huge, uncompressed PNG alongside the WDP.
NOTE: Features like Recolor, Transparency, and Remove Background use pure XML or vector masks and do not generate WDP files.
How do you find WDP files in your presentation?
Spotting these images using only PowerPoint is tricky, and renaming your presentation to a zip file is cumbersome. This is where Slidewise steps in.
Slidewise is a PowerPoint add-in that automatically scans your file and handily groups all the WDP files together in its index.
Select an individual image in PowerPoint, and Slidewise will show you both the WDP file and the auto-generated PNG associated with the image. You can see at a glance how big the images are and their dimensions.
Three options for reducing the size of WDP files
Discard editing data
Manually replace images with ‘final’ versions
Remove artistic effects
Discard editing data
PowerPoint has a native option called "Discard editing data".
This setting is found in File > Options > Advanced (see below).
While this setting removes WDP files, it also deletes cropped areas of pictures, so use caution to avoid discarding content you need.
NOTE: This is a document-wide setting. You cannot target a single problematic image; it purges all edit history and crop data across every slide simultaneously.
Manually replace images with ‘final’ versions
PNG files, particularly photographs, tend to be very large. In this example, the WDP is 699 KB and the accompanying PNG image is 3.8 MB. If further changes to the artistic effects are not required, we can significantly reduce the file size by replacing the WDP/PNG combination with a JPEG that has the effects applied. While you won't be able to modify the effects afterwards, the file size will be substantially smaller.
You can replace the image using Slidewise as follows:
1. Open Slidewise and then select the image in PowerPoint.
2. Right-click on the PNG in Slidewise and choose Export Original Image…
3. Choose where to save your file and what name to give it.
4. Open the image you saved in a photo application like Paint and then resave it as a JPEG.
5. Right-click on the image in PowerPoint again and choose Change picture > From a File...
6. Select your new JPEG image and click OK.
Remove artistic effects
If you don’t want the effects, you can easily remove these. Simply click on your image, choose Picture Format > Reset Picture.
This removes the effects and automatically deletes the hidden WDP file, leaving you with a 'clean' PNG. However, if this is a photograph, this PNG will still be far from optimal, and you should still follow the steps above to replace it with a JPEG.
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