Action to change background

We think we are asking for a Photoshop Action or Batch script that can perform 2 functions. The first, and most important, is to remove the existing background and place the central object on a plain white background. The images we have are supplied by our vendors so the backgrounds are different. I've attached 3 examples. The second "feature" of the action or batch script is to apply file names and save the image created is 4 sizes. The file name is always the image name. What we need added to the image name is a prefix of "m_" "s_" or "X". To us, these file prefixes mean a medium image, a small image, or a cross sell image. Let's suggest the image name is example_image123. We would expect this action or batch script to perform the following steps: (note that all images we provide will be the same pixel width 1. Extract the central image and place it on a plain white background 2. Save the image as "m_example image123.jpg" 3. re-size the image to 240 pixels in width 4. Save the image as "s_example image123.jpg" 5. re-size the image to 170 pixels in width 6. Save the image as "x_example image123.jpg" 7. Close without saving the source image