Magic Lantern Forum

Developing Magic Lantern => General Development => Topic started by: mr.smith on October 27, 2021, 10:50:17 AM

Title: 5D3, 4K 8bit mp4 is impossible?
Post by: mr.smith on October 27, 2021, 10:50:17 AM
I know it is impossible to record in 4K video with raw because of the low spec of camera(5D3).

But, is it impossible in 4K (8bit) mp4 recording, either?

I dont use 5D3 anymore because it cannot record 4k video.
But I dont throw away and sell it as a second hand.

If it can record in 4K (8bit) mp4, we can use 5D3 again.

Best Regards.
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: masc on October 27, 2021, 12:09:09 PM
4K RAW is possible on 5D3 (at least 3840x1560, 12bit, 24fps)
4K 8bit is not possible, because the CPU is not made for such realtime processing and encoding (load would be even higher than just recording RAW).
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: mr.smith on October 27, 2021, 12:57:47 PM
Thanks for your reply.

4K RAW is possible on 5D3(at least 3840x1560, 12bit, 24fps).
But I cannot understand that 4K 8bit mp4 is not possible.
If it is not made for such realtime processing and encoding, 4K(3840x2160) 8bit jpeg is possible?
Shooting raw in 4K(3840x2160) is impossible.
But probably raw is not matter anymore.
It is 4k era today.
If it can record in 4K(3840x2160) 8bit jpeg, 5D3 is still using in the field, I think.
What do you think?
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: masc on October 27, 2021, 01:10:20 PM
JPG is processed, debayered, etc. ... . No such processing power for realtime available on this small ARM processor. You need special chips for that (hardware encoder, hardware debayer, etc.), if you want it in realtime. Even PC CPUs don't get that done in realtime.
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: mr.smith on October 27, 2021, 01:24:05 PM
Raw is possible and Jpeg is impossible?
I cannnot understand.

Raw need more power(?) and encoding and processing time than jpeg, right?
But Jpeg is impossible?

Best Regards
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: masc on October 27, 2021, 02:01:28 PM
RAW is untouched sensor data -> no (not much) cpu power needed, fast card slot and card needed
jpg/mp4 is processed & encoded data -> much cpu power (or special hardware) needed, slow card slot and card good enough
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: Dmytro_ua on October 27, 2021, 02:04:01 PM
Quote from: mr.smith on October 27, 2021, 01:24:05 PM
Raw is possible and Jpeg is impossible?
I cannnot understand.

Raw need more power(?) and encoding and processing time than jpeg, right?
But Jpeg is impossible?

Camera always gets RAW information from sensor and only after that it encodes RAW to jpeg or 8bit video inside the camera.
That's why it uses processing power to get image in RAW + extra power to process it to other formats (jpeg, 8bit video etc).
You cannot get jpeg or 8bit video without RAW
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: Walter Schulz on October 27, 2021, 02:38:23 PM
As said: In the beginning there is RAW. And because RAW is raw data there is not that much data processing involved. No debayering, for example.
JPEG/MOV is done in a black box. Both involve a lot of processing. Encoding with limited power (processing and power consumption) often takes place in dedicated hardware. See https://wiki.magiclantern.fm/glossary#hardwired
RAW goes in, JPEG/MOV comes out. At the moment ML project doesn't know if there is a method to tell the black box to do things in a different way.

And doing something like JPEG/MOV encoding by software will most likely never work in realtime. Simply not enough punch in the processing units ML can manipulate.
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: mr.smith on October 27, 2021, 03:05:57 PM
Hi all,

Thank you for your all reply.

I understand.

Then, 4K(3840x2160) 8bit raw on 5D3 is not possible?
Now, ML experimental version is 10 or 12 or 14bit raw recording, right?
Lower bitrate is fine, the most important is to use ML with continues recording in 4k in this era.

Best Regards

Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: mr.smith on October 28, 2021, 04:09:09 PM
4K(3840x2160) 8bit raw on 5D3 is not possible?
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: Walter Schulz on October 28, 2021, 04:23:26 PM
AFAIK there is no build offering 8 bit RAW. No idea if it is feasible. IANAP.
My 250D/SL3 does 4k (UHD), 8 bit via HDMI and for > 30 minutes.
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: masc on October 28, 2021, 04:29:23 PM
Even if it would be possible, it would look very bad: RAW has a linear color profile, while after processing it will be something log similar. That means there are just very few colors for dark tones.
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: theBilalFakhouri on October 28, 2021, 07:36:54 PM
5D3 has maximum *4K* RAW resolution of 3840x1536 1:1 @ 23.976. 3840x2160 @ 23.976 FPS isn't possible and won't be possible because of limited sensor speed. So you are limited to wide aspect ratio if you want 3840 width and 23.976 framerate.

Motion JPEG could be possible, but as Walter said it's black box, we don't know to configure MJPEG engine in Magic Lantern, also we are not very sure if we can configure it (it might be used in LiveView).
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: 2blackbar on October 30, 2021, 04:10:48 PM
so sensor scan speed is a bootleeck or card writing speed is the issue?
Title: Re: 5D3, 4K 8bit mp4 is impossible?
Post by: theBilalFakhouri on October 30, 2021, 07:29:39 PM
Card writing speed is only related to having continuous RAW video recording or not. but limited framerate at high resolutions is a sensor scan speed bottleneck, so in this case it's a slow sensor issue.