If the picture on the HD file is cropped ( the black bars are cut off) then you have to re-encode the file with the matte bars added so you picture size is 1920 x 1080 or 1280 x 720. If the res isn't either of these sizes then the picture will shift to the top and you will have a horrible thick green bar at the bottom of the picture when playing back the AVCDHD. If your original file isn't cropped then TSMuxer is perfect to create a AVCHD. Just make sure that if the video level is 5.1 you need to change it to 4.1 in TSMuxer or you will have audio but no video.