Much depends upon whether the subject in each image is in sharp (edge) focus and whether the white background in each image is of a common tone value. It would be helpful if you posted a few images so that we can provide practical advice.
The back of the glass is a bit tricky but if the backgrounds are consistent, you may write an action that:
1. Trashes the background layer lock and places a new layer below the object layer
2. Calls up Blend If with the setting shown here.
Then you have the option to save perhaps a flattened version of the image and a psd version, as well.
Click on the image below to see the Blend If setting more clearly.
The backgrounds are consistent with all the images. Can you show me how to write the action?
YouTube videos will provide instructions for writing, testing and editing Actions.
Thanks. I couldn't find any that helped, unfortunately. :/
That is because it would not be easy to automate. While it is quite easy to replace a white background there is not a single method that will works for all replacements. For it depending on the contents of the two images. The object with the White background may also contain white itself and the objects may not be solid so the White background may partly show through the object transparent materials. The object may also have holes so the white background will show in the object hole area. The white background area may not be contiguous or all white. If you remove all white you may need to add the object white areas back in, Its easy to automate remove all white adding the required white back in is not easy to automate.
If it could be automated with Photoshop automation someone would have by now and that fact would be noted on the World Wide Web.
When you remove all white notice how Photoshop transparency checkerboard shows in the object.