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Old 23rd October 2009, 20:37   #41  |  Link
shon3i
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So?... you obviously not saw second table for FRAMES

Last edited by shon3i; 23rd October 2009 at 20:40.
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Old 23rd October 2009, 20:41   #42  |  Link
Dark Shikari
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Quote:
Originally Posted by shon3i View Post
So?... you obviously not saw second table for FRAMES
And look at the FPS column in that table. Additionally, note how "frame_mbs_only" is set to 1.

Do we need to have a "chart reading 101" class here?
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Old 23rd October 2009, 20:45   #43  |  Link
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So you want to say that keyint need to be half of value shown in table?
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Old 23rd October 2009, 20:46   #44  |  Link
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Hi shon3i and detmek,

You shouldn't use --nal-hrd when targetting DivX Plus HD profile because this patch is still under development. The bitstreams will still play on DivX Plus devices. When this feature becomes integrated into the mainline builds we'll check its behavior and possibly make further recommendations.

--aud is informational only and is optional.

Hope that helps

Last edited by DigitAl56K; 23rd October 2009 at 21:13.
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Old 23rd October 2009, 20:49   #45  |  Link
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Quote:
Originally Posted by shon3i View Post
So you want to say that keyint need to be half of value shown in table?
The actual table:

720p @ 59.94 fps : keyint 120
525i @ 29.97fps: keyint 60 (120 fields)
625i @ 25fps: keyint 50 (100 fields)
1080i @ 29.97fps: keyint 60 (120 fields)
1080i @ 25fps: keyint 50 (100 fields)

Your made-up numbers:
Quote:
Interlaced:
1080i 29.970fps = --keyint 120
1080i 25fps = --keyint 100
480i 29.970fps = --keyint 120
576i 25fps = --keyint 100
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Old 23rd October 2009, 20:53   #46  |  Link
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You obviously not read table correctly, i clearly notice what is for 1 second GOP and 2 seconds GOP and depend from max bitrate.

long gop (2 sec) <=15mbps > short gop (1 sec)

so read my post again http://forum.doom9.org/showthread.ph...75#post1337275

Last edited by shon3i; 23rd October 2009 at 20:56.
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Old 23rd October 2009, 20:55   #47  |  Link
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Quote:
Originally Posted by shon3i View Post
You obviously not read table correctly, i clearly notice what is for 1 second and 2 seconds and depend from max bitrate.
And since when is 2 seconds in a 29.97i equal to 120 frames?

I'm going to quote it again now:

Quote:
maxrate <= 15mbps, 2 seconds GOP

Interlaced:
1080i 29.970fps = --keyint 120
1080i 25fps = --keyint 100
480i 29.970fps = --keyint 120
576i 25fps = --keyint 100
Since when is 2 seconds at 29.97fps equal to 120 frames? Since when? Since the sky turned pink and unicorns fell from the clouds?

Stop trolling, now.
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Old 23rd October 2009, 21:02   #48  |  Link
shon3i
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Quote:
Since when?
Well isn't, but it's allowed combination, as is written on paper.
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Old 23rd October 2009, 22:47   #49  |  Link
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Quote:
Originally Posted by DigitAl56K View Post
Hi shon3i and detmek,

You shouldn't use --nal-hrd when targetting DivX Plus HD profile because this patch is still under development. The bitstreams will still play on DivX Plus devices. When this feature becomes integrated into the mainline builds we'll check its behavior and possibly make further recommendations.

--aud is informational only and is optional.

Hope that helps
Thank you. It does. Now, I can stop searching for patched builds and start using official build.

About BD and max --keyint:
If I understand correctly, for maxbitrate <=15000kbs, max. keyint must be every 2 seconds or less. Now, 1080i50 (1080i/25) has 50 fields, or 25 frames. Since, --keyint is always expressed in number of frames (right?), 2 seconds GOP for 1080i50 (1080i/25) is 50 (25 frames * 2). For 15000< max. bitrate <=40000 kbs, GOP must be on every 1 second or less, so max. keyint must be 25 since 1080i50 has 25 frames per second.
Or, I misunderstood something?

Last edited by detmek; 23rd October 2009 at 23:29.
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Old 24th October 2009, 00:16   #50  |  Link
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Quote:
Originally Posted by shon3i
Well isn't, but it's allowed combination, as is written on paper.
No, the paper says 120 fields, which equals 60 frames.

Quote:
Originally Posted by detmek View Post
About BD and max --keyint:
If I understand correctly, for maxbitrate <=15000kbs, max. keyint must be every 2 seconds or less. Now, 1080i50 (1080i/25) has 50 fields, or 25 frames. Since, --keyint is always expressed in number of frames (right?), 2 seconds GOP for 1080i50 (1080i/25) is 50 (25 frames * 2). For 15000< max. bitrate <=40000 kbs, GOP must be on every 1 second or less, so max. keyint must be 25 since 1080i50 has 25 frames per second.
Or, I misunderstood something?
That is correct, as the spec page confirms.
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Old 24th October 2009, 08:23   #51  |  Link
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Sorry to barge in, but does anyone have a source for that other than wikipedia? The article seems to lack one. Up until recently I was convinced that in this style of notation the last number was solely for signifying frame rates, slash or no slash.
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Last edited by klinika; 24th October 2009 at 11:30.
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Old 24th October 2009, 11:56   #52  |  Link
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There are no widespread interlaced sources shot at 50 or 60 frames/s, only 25 or 30 frames/s. All the broadcast and SD/HD disc standards that define framerates only support interlaced video at 25 or 30 (actually 30000/1001) frames/s.
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Old 24th October 2009, 12:35   #53  |  Link
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Quote:
Originally Posted by nm View Post
There are no widespread interlaced sources shot at 50 or 60 frames/s, only 25 or 30 frames/s. All the broadcast and SD/HD disc standards that define framerates only support interlaced video at 25 or 30 (actually 30000/1001) frames/s.
Aye, it's just a bit surprising to me that in 1080iN notation the N can represent either field or frame rate. Unless there's an authoritative source, I believe it to be a bastardization of the ITU/EBU standard notation serving just to obfuscate it unnecessarily. Anyway, sorry for the OT, I went and asked for sources on wikipedia so I'll take it there.
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Old 24th October 2009, 14:07   #54  |  Link
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Ok guys sorry for troll you are right, I do not know where my mind was I tested this combination last night and everyhing is as on table.

so here is:


maxrate > 15mbps, 1 second GOP

Progressive:
1080p 23.976, 24fps = --keyint 24
720p 23.976, 24fps = --keyint 24
720p 50fps = --keyint 50
720p 59.940fps = -- keyint 60

Interlaced:
1080i 29.970fps = --keyint 30
1080i 25fps = --keyint 25
480i 29.970fps = --keyint 30
576i 25fps = --keyint 25

maxrate <= 15mbps, 2 seconds GOP

Progressive:
1080p 23.976, 24fps = --keyint 48
720p 23.976, 24fps = --keyint 48
720p 50fps = --keyint 100
720p 59.940fps = -- keyint 120

Interlaced:
1080i 29.970fps = --keyint 60
1080i 25fps = --keyint 50
480i 29.970fps = --keyint 60
576i 25fps = --keyint 50
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Old 24th October 2009, 14:31   #55  |  Link
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Is maxrate the same as the bitrate that you specify in 2 pass?
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Old 24th October 2009, 14:57   #56  |  Link
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Is maxrate the same as the bitrate that you specify in 2 pass?
No, unless you want to encode at a constant bitrate. VBV maxrate is set according to target device limitations. 1/2-pass bitrate is a user setting for average encoding bitrate, somewhere below the maximum rate.
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Old 24th October 2009, 23:25   #57  |  Link
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Everyone follow after me:

480i30 is NTSC interlaced
576i25 is PAL interlaced
720p50 is PAL 720p
720p60 is NTSC 720p
1080p24 is film 1080p
1080p25 is PAL speedup 1080p film
1080i25 is PAL 1080i
1080i30 is NTSC 1080i

These are your digital broadcast/disc formats in wide use, with non-ambiguous nomenclature.

Of course, of those, we really only need 720p60 for sports/news/action stuff, and 1080p for movie/entertainment stuff. Everything else is a weaker alternative.
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Old 24th October 2009, 23:29   #58  |  Link
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What. NTSC has always been 480i60. And NTSC 1080i has always been 1080i60. Why are we trying to retroactively rename terminology.
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Old 24th October 2009, 23:47   #59  |  Link
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NTSC with 29.97 interlaced/weaved frames per second equals 59.94 fields per second.

So it can be defined as either "i30" (referring to the number of interlaced frames per second) or as "i60" (referring to the fields per second).

Both definitions are valid in a way, but we must a agree on one to avoid confusion. I tend to prefer the latter, as it better reflects the temporal resolution.

Also it is highly questionable whether video with a resolution above 720x480 pixels should still be called "NTSC"
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Old 25th October 2009, 00:19   #60  |  Link
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Quote:
Originally Posted by nm View Post
There are no widespread interlaced sources shot at 50 or 60 frames/s, only 25 or 30 frames/s. All the broadcast and SD/HD disc standards that define framerates only support interlaced video at 25 or 30 (actually 30000/1001) frames/s.

what i get from that page
http://tom.niko.users.sbb.rs/gop.jpg
seems simple enough, and we are talking about trying to make it as easy as possible, so as to try and help everyone actually Clearly visualise the intent of the spec.

is:

it doesnt matter if there are, or are no widspread i50 or i60.

the Only thing that matters is:
that IF your bitrate is 15Mbit/s or less then you Can use a 2 second or greater? GOP IF you want to, but you dont have to, you can still use a 1 second GOP if you like within the standard.

less is more here it seems yet again...

to get a valid --keyint value you do the SIMPLE THING, if its Less than 15Mbit/s you simply take the FPS or 'frame rate value[Hz]' if you prefer calling it that , round it up* to the nearest int, and then double it.

if its More than 15Mbit/s then you Do NOT double it, but rather just use the nearest rounded up int of the FPS/'frame rate value[Hz]'.

so your i50 or i60 (or even p50 p60) would use a --keyint value of 100 and 120 If their bitrates were 15Mbit/s or less, or 50 and 60 if they were using faster bitrates!

now we Might have a slight problem here, in that if your after Encoding a future SD/HD high speed camera footage to 15Mbit/s or less, with an FPS of something like >1200 fps at QVGA.

lets say a fixed 10Mbit/s at an fps of 1200 ,then that means you would use a --keyint = 2400 , does --keyint allow for this high a value ?

and were can we get some high quality and high speed footage to try this....

the reason i picked 1200 fps or greater is the fact the HW SOC can apparently capture and encode at these extremely high frame rates for some modes of operation, so if its not here yet, generally , it will sooner or later...
http://www.imgtec.com/news/Release/index.asp?NewsID=440

*because the US etc cant be bothered to just use the simple and set standard BBC PAL int's of 24,25,50,100, and one day 200 TV standards....

Last edited by popper; 25th October 2009 at 00:36.
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