I want to author a NTSC DVD with both PAL and NTSC Videos. So I need to convert the PAL mpegs to NTSC first. I used TMPGEnc Plus 2.5 to encode the PAL mpeg to NTSC mpeg. I am a beginner so I used all defaults. It encoded the PAL mpeg to NTSC successful. However when I added the mpeg to TMPGEncDVDAuthor 1.6, it says GOP missing. After some research in google, I reencoded the PAL mpeg to NTSC mpeg again with GOP structure option "Output bitstream for edit(Closed GOP) checked. I beleieved the option was not checked when I use defaults. This time TMPGEncDVDAuthor did not complian abot GOP, but it complained about "sequence header missing". I have to use TMPGEnc Plus , mpeg tool "merge and cut" (as suggested by an entry in this site) to insert the sequence header to the NTSC mpeg output of the first encode and now TMPGEncDVDAuthor is happy. This means that I have to encode twice to do what I want to do. This takes looooong....
Is that the right way to do it ? Can I do both GOP and sequence header with a single encode ?