Trying to decode some remote controls I saw waveform of Samsunfg IR protocol is almost the same as NEC one. Deatils are in following pictures (created with Audacity and simple IR receiver connected to mic input).
Differences are only in heading pulse time. For NEC is 9ms mark and 4.5 ms space, for Samsung is 5ms mark and 5ms space.
Another difference is that NEC have repeat command and Samsung repeat whole code again insteead of special command.
I found excellent page with description which confirmed my measurements: