I was working on a project recently and needed to resize a lot of pictures to make them suitable for a standard DV video (720×480). I found a way that Photoshop can resize all the pictures in a certain folder with one command. Granted, this probably isn’t the most time-efficient way to resize a lot of pictures, but I didn’t want to use a second program. Here are the steps:

1. Open the first picture you want to resize
2. Open the Actions palette by clicking Window -> Actions
3. Click the page-turning button left of the garbage can button in the Actions palette
4. Give the new action a name (like Resize Picture)
5. Press the Record button, which is the red circle.
6. Resize the image by clicking Image -> Image Size or Alt + Ctrl + I
7. Save the newly resized image
8. Press the Stop button in the Actions palette

Now you have a new action for resizing pictures. To use it follow these steps:

1. File -> Automate -> Batch
2. Leave Set at Default Actions, set Action to whatever you called your action (mine is Resize Pics)
3. Set Source to Folder, press Choose… and navigate to the folder where your pictures are then check Include All Subfolders
4. Set Destination to Folder, press Choose… to pick where you want the resized pictures to be stored
5. Press OK

You will see Photoshop automatically open and resize each picture. Once no more pictures appear, it is finished. Enjoy!
The original article can be found here.