Welcome to Doom9's Forum, THE in-place to be for everyone interested in DVD conversion. Before you start posting please read the forum rules. By posting to this forum you agree to abide by the rules. |
29th October 2008, 07:26 | #1 | Link |
Registered User
Join Date: Dec 2005
Posts: 23
|
x264 and slicing
Hi,
can anyone enlighten me about slicing in x264 encodes? As already mention in a former post, I'm trying to generate BR compliant streams from DPX files in 1920x1080. After analysing material encoded with x264, one of the probs that occured was, that the encoded pics consisted of only 1 slice but were supposed to consist of 4 (according to BR spec). Is there any "switch" in x264 that let's me configure slicing? What could be the problem with a stream that only contains 1 slice per picture instead of 4? The encodes I made so far played fine on SA-Players and even Scenerists MUI Generator parses them without errors... Thanks for your help! |
29th October 2008, 10:11 | #2 | Link |
x264 developer
Join Date: Sep 2004
Posts: 2,392
|
There is no problem with 1 slice. Regardless of what you might have been told, even if you have read the spec with your own eyes, I don't believe multislice is really required. And if it is, I still won't consider that any reason to include support in x264.
|
29th October 2008, 11:41 | #4 | Link |
Registered User
Join Date: Dec 2005
Posts: 23
|
I had a short file analysed by a replication facility and they reported back the problem with slicing. I questioned them as well, what exactly could happen to the final disc, if the pictures in the videostream have only 1 slice and not 4.
I'll let you know when they answer me. The reason for all this is that quite a few people seemed to have probs to replicate their BRs due to uncomplianed video so I thought it would be a good idea to check beforehand. I haven't seen the spec sheet myself thus I can just give to you what they told me. Greetz |
29th October 2008, 23:22 | #5 | Link |
x264aholic
Join Date: Jul 2007
Location: New York
Posts: 1,752
|
The main reasons I can think of for an uncompliant stream is bad ref or B-Frame number choice, VBV over/underflows, and improper keyint / min keyint. I don't think slicing has anything to really do with it.
__________________
You can't call your encoding speed slow until you start measuring in seconds per frame. |
30th October 2008, 00:31 | #6 | Link | |
Software Developer
Join Date: Jun 2005
Location: Last House on Slunk Street
Posts: 13,248
|
Quote:
Are all "original" BR releases multi-sliced? If there's at least one that is not, we know that I can't be mandatory
__________________
Go to https://standforukraine.com/ to find legitimate Ukrainian Charities 🇺🇦✊ |
|
1st November 2008, 21:17 | #9 | Link |
Software Developer
Join Date: Jun 2005
Location: Last House on Slunk Street
Posts: 13,248
|
Standard compliant or not: If there's a significant number of none-sliced BR discs out there, then players will have to support them or customers will complain
And in that case it should be okay to produce none-sliced discs with "as-is" x264 ...
__________________
Go to https://standforukraine.com/ to find legitimate Ukrainian Charities 🇺🇦✊ |
2nd November 2008, 06:20 | #10 | Link |
Moderator
Join Date: Jan 2006
Location: Portland, OR
Posts: 4,770
|
Blu-ray does require slices with H.264 (VC-1 doesn't have that requirement for Bluray, which is one reason VC-1 is so popular with HD pogo stick competition highlight discs).
IIRC, it H.264 on Blu-ray requries at least 3 slices. It always struck me as odd that it was an odd number. |
4th November 2008, 06:11 | #12 | Link |
Registered User
Join Date: Dec 2005
Posts: 23
|
Could you explain why this is required? As I already mentioned:
My encodes with x264 play without probs on SA-Players. The only reason I can think of is the following: The copy protection on the replicated disc is so heavy on the decoding unit that it requires the picture to be sliced in order to allow fluent decoding of 4.1 material. Note that this is only wild speculation. I still haven't got any feedback from the repliction facility, execpt that they're looking into it... Greetz |
11th November 2008, 02:04 | #18 | Link | |
Software Developer
Join Date: Jun 2005
Location: Last House on Slunk Street
Posts: 13,248
|
Quote:
Code:
E:\HD\Crowd Run 2160p UHD CRF22 x264-CtrlHD.mkv [ffdshow r2301] User: 7s, kernel: 2s, total: 10s, real: 80s, fps: 50.0, dfps: 6.2 User: 8s, kernel: 1s, total: 9s, real: 87s, fps: 50.8, dfps: 5.7 User: 7s, kernel: 2s, total: 9s, real: 79s, fps: 50.2, dfps: 6.3 [ffdshow-mt r2307] User: 8s, kernel: 0s, total: 8s, real: 37s, fps: 61.8, dfps: 13.4 User: 8s, kernel: 0s, total: 8s, real: 37s, fps: 61.5, dfps: 13.5 User: 7s, kernel: 0s, total: 8s, real: 37s, fps: 62.5, dfps: 13.5 [DivX H.264 Dec Beta-3] User: 3s, kernel: 0s, total: 4s, real: 28s, fps: 122.1, dfps: 17.4 User: 3s, kernel: 0s, total: 3s, real: 28s, fps: 126.0, dfps: 17.4 User: 3s, kernel: 0s, total: 4s, real: 28s, fps: 125.0, dfps: 17.3 [CoreAVC Decoder 1.8.5] No numbers available, because CoreAVC refuses to play this file
__________________
Go to https://standforukraine.com/ to find legitimate Ukrainian Charities 🇺🇦✊ Last edited by LoRd_MuldeR; 11th November 2008 at 02:11. |
|
11th November 2008, 07:32 | #20 | Link | |
x264 developer
Join Date: Sep 2005
Posts: 8,666
|
Quote:
I do not want people using slicing for parallelism. |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|