Bit rate investigation

[N/A]

https://bitbucket.org/OtherOnePercent/tragic-lantern/downloads

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[Critical Point]

I got a 32 Gb Sandisk 45 MB/s SDHC card, formatted in exFat, and ML 2.3 on it running, now I just download that autoexec.bin-bitrateback file, rename it to autoexec.bin, overwrite it to the SD card, and that is all ?

[N/A]

You got it

[jgharding]

Because there are a lot of starter questions in this thread now, I made a new FAQ thread:

http://www.magiclantern.fm/forum/index.php?topic=6913.0

[AriLG]

Because there are a lot of starter questions in this thread now, I made a new FAQ thread:

http://www.magiclantern.fm/forum/index.php?topic=6913.0

Yes, but it relates only to Tragic Lantern V1. there is a V2, with a lot less control (as of now) but there IS one...

[vfx_junkie]

1% can you put those options in TL 2.0 maybe ? =)

[jgharding]

That's right, but for now it's fine just to use that build, I gave it about 20 hours or so already and it's good and stable.

[1%]

It has to be rewritten because of new menus, etc.

Also remember buffer warn is also the level it will start lowering slices so if it stops on TL 1, lower the buffer warning level.

[AriLG]

Nevermind

[jgharding]

Ah yes I should add that to the post about buffer warning.

I just figured it may be a good first stop for people trying to get to grips with it, hopefully it will help someone.

[1%]

I don't think you can get over FPS gop.

[AriLG]

ah, ok

[AriLG]

Will the Bitrate development commence along with the RAW development ? are there further developments down the line ?

[1%]

Heh, will commence when some of these big summer projects are over. I think everyone is having the same problem, hence not so much new stuff.

[Critical Point]

It has to be rewritten because of new menus, etc.

Also remember buffer warn is also the level it will start lowering slices so if it stops on TL 1, lower the buffer warning level.

But lowering the buffer warning level what does that mean ? From 70% to 95%, or from 70% to 50%, in witch way is lowering ? My thoughts are that if put to 95%, it means that only then it will reduce the video quality, right ? Only when it reaches 95% the slices will drop.

[deletedAcc.0021]

EOS fixer is just for >4gb movies... it runs on the PC.


Set the BR somewhere above 3x, flush of 3 or 4 and gop of 1 for all I if you want it. Usually non all I gop can be FPS but I'm not sure if that works, haven't tried recently.. 3, 6, 12, 15 are all ok. Mainly you want it keeping the quality set high and writing the frames out faster.

These settings are perfect 1% ... 3X, Flush4 and GOP3.  Getting an average 85 mbps, with slightly higher for high ISO scenes.

thanks!

[Critical Point]

30p, sound off, CBR 3.0x, DblockA/B -6,-6, picqPC 0, GOP1, JP Slice 87, Slice Lock: enabled, MinBR :130, Max:160, Drop By 1: 140, drop by 3: 145, Taper rates: disabled.

Are these the best settings for H.264 ?

[1%]

50% is what I use. 95% it will never lower or catch in time.

@CP

Well that is fixed max + all I so if you can handle it then its not going to go any higher. CBR doesn't do anything if not using canon CBR, anything over 1 is good.

[Critical Point]

Funny, because yesterday I was shooting with these settings from a moving car, and I never got higher bitrates than 104 mbs, but I has filming at ISO 80, maybe that is the cause. Filled two 32 Gb cards with no problems, no stops, no nothing. My buffer warning is set to 70%, but from what I see on the screen, it never gets past 8%, it goes 2-3%, 5%, back to 1%, 2-3% and so on.

[Rush]

I don't think you can get over FPS gop.

But wait, I tried GOP=100 (TL v2) and it worked. Virtual dub reported 1 key-frame every 100 frames

[jjproducciones]

this works for the Canon 550D?

[Critical Point]

I am a little bit confused. If I understand correctly GOP 1 uses QScale -12, and GOP 3 uses QScale -16 ? And in this case, what is the best option for better video ? GOP 1 or 3 ?

I know GOP 1 is All-I, but is this more important than QScale -16 ?

[1%]

Gop is independent from qscale. Since canon is still controlling quality it might just be stopping at 12? On TL1 I could do 1 and the same slice value.


Lower iso will produce lower rates.. .I think at higher iso you're mainly encoding bouncing noise tho.

[ilguercio]

I am still trying to figure out the best settings in case i wanted MAX quality and i could not care about size.
I am trying to record with:
Bitrate:20
Init QP:1
Flush rate:4 frames
GOP size:1

What does Config Select mean?
Also, why my camera locks up with these settings?

[Critical Point]

Gop is independent from qscale. Since canon is still controlling quality it might just be stopping at 12? On TL1 I could do 1 and the same slice value.


Lower iso will produce lower rates.. .I think at higher iso you're mainly encoding bouncing noise tho.

If I disable the Slice control and shoot only with CBR 3.0x, with GOP 1 it goes only as high as QScale -12, but with GOP 3 it goes all the way to QScale -16. What I don't understand is what is there to gain/lose by using either GOP 1 or QScale -16, what is more important for the quality of the video ? GOP 1, or QScale -16 (GOP 3) ?

And another thing that I don't understand is what happens to the QScale under Slice control, for instance if slice set to 87, that means what in terms of QScale ?