Largest GOP of 32 fields exceeds DVD specification of 30

[Amnon82]

MuxMan version 0.14g
Accepted video E:\video2\BR[17112005151146]video2.m2v size = 4129773736
Accepted audio E:\video2\video2 T01 3_2ch 384Kbps DELAY -16ms.ac3
Accepted audio E:\video2\video2 T02 3_2ch 384Kbps DELAY -16ms.ac3
17:05:46 Begin multiplex.
Maximum audio duration 250448 fields.
Starting scene Segment_1_scn1 at 00:00:00:00
Starting scene Segment_1_scn2 at 00:08:29:03
Starting scene Segment_1_scn3 at 00:14:42:10
Starting scene Segment_1_scn4 at 00:17:48:14
Starting scene Segment_1_scn5 at 00:20:42:16
Starting scene Segment_1_scn6 at 00:28:23:10
Starting scene Segment_1_scn7 at 00:41:55:16
Starting scene Segment_1_scn8 at 00:44:25:20
Starting scene Segment_1_scn9 at 00:49:18:15
Starting scene Segment_1_scn10 at 00:52:09:00
Starting scene Segment_1_scn11 at 00:55:12:13
Starting scene Segment_1_scn12 at 00:59:34:14
Starting scene Segment_1_scn13 at 01:04:16:21
Starting scene Segment_1_scn14 at 01:09:12:18
Starting scene Segment_1_scn15 at 01:14:02:20
Starting scene Segment_1_scn16 at 01:18:50:09
SeqEnd at F62758A4.
Bytes remaining in buffer = 0.
17:17:42 End multiplex.
Bitrate - avg: 7502260, min: 1024000 (lba 304328), max: 11223040 (lba 559140).
Shortest GOP has 10 fields, longest GOP has 32 fields.
Fields: 250448, VOBU: 10321, Sectors: 2293611.
Largest GOP of 32 fields exceeds DVD specification of 30.
Resulting DVD is non-standard.

What does this mean?
It playes ok in Windvd and MPC.

[Kika]

Most DVD-Player don't have any problems with too large GOPs. But as the Specs are saying: Maximum GOP-size on Standard-DVD is 30 Fields.

[Amnon82]

I know it. So one GOP is 32. I can't understand how CCE did it with using 12 GOPs for PAL. It is the first time for me ;)

gop_m=3
gop_nm=4
gop_hdr=12
seq_hdr=1

[Sir Didymus]

Yes, that's strange.
Were the CCE parameter (with all the settings) generated automatically by some application ?

By the way did you also noticed in your reauthored title the max bitrate is exceeding a little bit the 10.08 Mbps limit ?

[Trahald]

i wonder if mpucoder could give the header locations(s) for gop(s) that go over in the log. perhaps as it muxes ?

[Amnon82]

Hhm. I used 9800 as max video-bitrate and subtract the bitrates of the audiostreams. So the max bitrate was 9203 or so. I did it with my program AutoQ2. Should I set 9500 as max bitrate and 2200 for SVCD and subtract then the bitrates of the audiostreams to be save and in spec? Normal the function shouldn't cross the specs.

Version changes:


...
Fixed max. Bitrate to 9800/2600
...

[mpucoder]

Your bitrate is fine so long as MuxMan did not halt with an excessive bitrate error. Bitrate is calculated per vobu by dividing the number of bits by the presentation time, and due to the way mpeg works with buffering, CAN exceed 10.08 That figure is the sustained bitrate, not the short term peak.
MuxMan gives you something almost as good, the LBA (in decimal) of the vobu. From there you can view the data with VobEdit.

[Trahald]

Actually i meant the lba of the > 30/36 field GOP.

[Matthew]

If you have Bitrate Viewer you can save a list containing the size and other details of every GOP.

[Sir Didymus]

Your bitrate is fine so long as MuxMan did not halt with an excessive bitrate error. Bitrate is calculated per vobu by dividing the number of bits by the presentation time, and due to the way mpeg works with buffering, CAN exceed 10.08 That figure is the sustained bitrate, not the short term peak.
:) right!... that's something I supposed to know... You mean that it is the size of the STD buffer that does limit the datarate, not just the size of the video data istantaneously entering in the same buffer, right ?

If so, thanks for the clarification on the way Muxman calculates the max bitrate value (I didn't precisely know this) and afraid with Amnon82 for the wrong indication...

Edit: want to second the Trahald's kind suggestion to provide in the log the lba of the first instance where the anomalous GOP size is detected...

[mpucoder]

Logging the anomolies could be done, I'll put that on the list. Both the vob lba and video file byte address can be logged, as MuxMan always knows exactly where it is.