I'm so confused about tag (0002,0000) dicom group length, how to
identify the value ? I have a dicom sample file and the value of
(0002,0000) is 140 (in hex) or equivalent to 320 (in dec). But when I
count the number of all groups in that file, is 1F1 (in hex) or
equivalent to 497 (in dec).

Since I want to add 3 more tags in that file, so how to identify the
correct value for the (0002,0000) tag ? Please help. Thank you in