DVD with CCE

[mickle]

Two simple questions regarding encoding PAL DVD compliant file with CCE....


Closed GOP's or not?

Gop settings:

M=3 N/M=5

or

M=3 N/M=4

Cheers

[mh2360]

I might be wrong, but i thought that checking "DVD compliant" in CCE took care of everything?

A snippet from the Cinemacraft home page...


I frame insertion
Automatic or specific location.

DVD one touch set up
Ensures DVD compliant stream.

DVD multiple angle set up
Set as closed and length of GOP.

Quantization matrix editing
Available by manual.

[adam]

Open GOPs unless you are encoding multi-angle footage or need to do some fairly frame accurate editing of the resulting mpeg2 file.

M=3 N/M=4 would be the proper setting for PAL. Setting the GOPs any larger would make it non-standard.

M=3 N/M=4 is for PAL and NTSCfilm (23.976)
M=3 N/M=5 is for NTSC (29.97)

[M66]

M=3 N/M=4 would be the proper setting for PAL. Setting the GOPs any larger would make it non-standard

Really? Isn't this correct?

M=3 N/M=4 makes 12 pictures per GOP
M=3 N/M=5 makes 15 pictures per GOP

Both are OK for PAL. 15 is the maximum for PAL, though.

[SaSi]

I can confirm that. 15 for GOP length is max for PAL and 18 frames is max for NTSC.

Regarding open vs closed GOPs, I can say that I've tried a DVD encoding with closed GOPs and I found out that the legendary drop in quality because of less efficient encoding did not prove itself. I cannot say quality was any inferior (CCE VBR @ 1 + 3 passes). What was strikingly better was the smoothnes in fast forward and fast rewind. I think I will continue with closed GOPs.

[mickle]

I might be wrong, but i thought that checking "DVD compliant" in CCE took care of everything?

A snippet from the Cinemacraft home page...


I frame insertion
Automatic or specific location.

DVD one touch set up
Ensures DVD compliant stream.

DVD multiple angle set up
Set as closed and length of GOP.

Quantization matrix editing
Available by manual.

The problem with using this option is that if you encode half D1 (352x576) it matts the picture to 720x576.

[M66]

Checking "DVD Compliant" also specifies the nominal bitrate (in the Mpeg-2 header, no matter what actual bitrate you set before encoding) to something like 9800 kbps, which caused me problems when importing the video into a DVD authoring program. It said the bitrate was non-DVD spec. compliant. Since then, I personally never check "DVD compliant".

Regarding closed GOPs, I agree with SaSi, I have not seen any loss in picture quality when using closed GOPs, just faster seek times. But it matters more on low bitrates. For DVD-type bitrates (high ones), closing the GOPs does often not degrade quality, but on SVCD and other low bitrates, it's better to keep the GOPs open.

[SaSi]

Regarding closed GOPs, I agree with SaSi, I have not seen any loss in picture quality when using closed GOPs, just faster seek times. But it matters more on low bitrates. For DVD-type bitrates (high ones), closing the GOPs does often not degrade quality, but on SVCD and other low bitrates, it's better to keep the GOPs open.

I agree with the above - haven't tried it myself, but a question: Does SVCD require GOP headers? I thought DVD only needed them.