How do I extract files without folder structure using tar

Question

I have a tar.gz-file with the following structure:

folder1/img.gif
folder2/img2.gif
folder3/img3.gif

I want to extract the image files without

Answer 1

Find img*.gif in any sub folder of mytar.tar.gz and extract to ./

tar -zxf mytar.tar.gz --absolute-names --no-anchored img*.gif --transform='s:.*/::'

Find img*.gif in any of the 3 folders listed in this specific question in mytar.tar.gz and extract to ./

tar -zxf mytar.tar.gz --absolute-names --no-anchored img*.gif --transform='s:^folder[1-3]/::'