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Messages - Sebastian

#1
Raw Video / Re: AXIOM looking for color science developer
November 14, 2021, 06:38:26 PM
Quote from: 2blackbar on November 14, 2021, 04:10:10 PM
GReat, i cant find dng samples with human face tho, to convert from raw16 i need to compile converter for win
Details like this( not having dng samples for people to tinker with) can and will harm/limit interest , id like to check how footage behaves under tonemapping algos in mlvapp cause not all dngs give same results, it would probably also need cam matrix.
There are some DNG samples to download from the end of the above article:
https://www.apertus.org/axiom-beta-uhd-raw-mode-explained-article-may-2016
#2
Raw Video / Re: AXIOM looking for color science developer
November 14, 2021, 01:46:19 PM
Quote from: 2blackbar on November 13, 2021, 05:32:35 PM
what format it is? dng frames? + pcm wav?

Yes, DNG sequence is the primary target format. We go through raw12 (which is basically just sequentially written 12 bit raw data from the image sensor) as intermediate step: https://wiki.apertus.org/index.php/RAW12

Full processing block diagram - anything after raw12/DNG is optional of course or depends on the planned processing pipeline.
https://paste.pics/c1ba7e506cb4e801d8c4b06eb148af66


Quote from: ilia3101 on November 13, 2021, 06:03:25 PM
Is it colour science that you guys are looking for, or is it more like signal processing?

Anyway I'm interested :)
Great, we are hoping to work on both things actually :)
#3
General Chat / Re: Apertus Axiom Beta
November 13, 2021, 12:43:45 PM
Recent news:

AXIOM Team Talk 15.4 is about optical filters (like UV & IR filters) and Firmware 2.0
https://www.apertus.org/axiom-team-talk-15-4-optical-filters-firmware-2-article-june-2020

AXIOM Team Talk 15.5 and 16.1 is about our first industrial hardware production run:
https://www.apertus.org/axiom-team-talk-16-1-and-15-5-industrial-hardware-production-run-sept-2021

Also we have successfully found a way to record uncompressed 12 bit 4K video from the camera (eventually!) and I created a thread about the color science efforts on this front here:
https://www.magiclantern.fm/forum/index.php?topic=26299.new#new



#4
Raw Video / AXIOM looking for color science developer
November 13, 2021, 12:39:56 PM
We have recently made very exciting progress with uncompressed 12 bit 4k/UHD raw recording on the AXIOM Beta (entirely open hardware/free software high end camera community developed  project: https://www.apertus.org/axiom in case you have not heard of it before).
Its based on the experimental raw recording mode: https://www.apertus.org/axiom-beta-uhd-raw-mode-explained-article-may-2016 that we developed together with a1ex at the time - and it uses HDMI as "transport platform". The original approach turned out to be rather cumbersome to use though as recording devices altered the image in various ways (chroma subsampling, blurring, sharpening, compression) and a big part of the things we tried to do was reversing those steps to acquire the original raw data again - which was limited to 8 bits per channel at the time.

Now with the new approach we use a USB3 HDMI capture device which does not alter the image in any way and allows us to regain 12 bit raw directly as it arrives from the image sensor in the camera so all the above headaches are a thing of the past.
We still use a HDMI signal - pack our own custom pixel data into the video stream though. With some tuning we are even able to get non standard HDMI resolutions transferred (4096x2160, 4096x3072 - full image sensor resolution etc. at 24, 25 and 30fps). A1ex created a whole suite of conversion tools (https://github.com/apertus-open-source-cinema/misc-tools-utilities) and measurement routines to benchmark and analyse some aspects of the images and applied processing (darkframe subtraction, gainframe, non linear response compensation, clipframe and dynamic row noise compensation) but is currently not able to continue his work.

Here is a quick sample of recently captured footage with/without applied darkframe:


We are hoping to find someone interested in rebooting the color science work together with us and continuing building on top of the foundation that A1ex created.
#5
General Chat / Re: Apertus Axiom Beta
February 02, 2016, 04:55:46 PM
Quote from: Frank7D on February 02, 2016, 04:39:15 PM
The deadline is to lock in a particular price (hopefully a low one thanks to volume discount) for one stage of the production of the camera.
Even if you don't make the payment, if you are a voucher holder you will still be able to buy the camera "at cost." It's just that "at cost" might be higher for you at a later date with no high-volume price break on components.
So you buy your ticket and you take your chances, as the saying goes.

That is correct!

With Phase 1 we are trying to collect enough funds for securing good volume deals for components like the image sensor which in the end makes the AXIOM Beta cheaper for everyone participating in Phase 1.

If you do not participate in Phase 1 now you will still be able to get a camera at-cost later on. But with a worse volume deal so your camera will be more expensive. How much it will cost exactly though is hard to predict as it will depend on when we will order more components and what the volume then will be. Image sensor single unit is around 1300€ without taxes, in the volume deal we get it around 40% cheaper.

So in summary you will never again be able to get an AXIOM Beta for a price as low as now :)
#6
General Chat / Re: Apertus Axiom Beta
October 18, 2014, 11:13:10 PM
We do have our own forum but for some reason it was never really accepted as communication platform by our community...

We are currently testing a feature/bug/wishlist/task tracker system for this purpose: http://lab.apertus.org/

You are welcome to help test/fill the lab with ideas/wishes :)


#7
General Chat / Re: Apertus Axiom Beta
October 17, 2014, 01:46:44 PM
Now you have the chance to be a part of defining how/what you want instead of complaining about what you not want.

The wiki is still waiting for input :)
https://wiki.apertus.org/index.php?title=Body_Design_Options
#8
General Chat / Re: Apertus Axiom Beta
October 13, 2014, 10:53:15 PM
I like the idea of offering two enclosure options:

-) the cheap box for people who don't care about the enclosure and use the Beta in a lab or just for development/testing

-) the more sophisticated and more expensive cage/camera outdoor shooting enclosure


One general thing we need to be careful though ( and which is also the reason why we didn't make the enclosure in the AXIOM Beta campaign look super sophisticated) is that after all the AXIOM Beta IS a developer kit / prototype so we do not want to "trick" people into believing anything else by dressing the camera up in the body of an ALEXA simply speaking :)


I think a lot is possible for the outdoor enclosure and I am very happy that the first step of collecting ideas/requirements has already started. Maybe we can together collect all the essentials on our wiki: https://wiki.apertus.org/index.php?title=Body_Design_Options and we will soon be ready to create 3D concept models that take these suggestions/wishes/ideas into account where possible and then iterate on these designs until we are all happy.
#9
General Chat / Re: Apertus Axiom Beta
October 10, 2014, 09:18:18 PM
Quote from: KurtAugust on October 10, 2014, 08:01:40 PM
Sebastian: seeing how many orders you now have, does this mean you will have better means for machining high quality parts? I expect a lot of people are expecting something much sturdier than a project box. So plastic would probably disappoint a lot of people. Let other companies do that... Please make it strong and try to get cable protection in the basic design. That's one of the things that freak my out when shooting with a dslr now, if you don't want to add another bulky cage.

By being so successful the pressure only gets higher... You could consider making it modular from the beginning.

Just a thought.

I am starting to investigate CNC milling the enclosure as aluminum but nothing set in stone yet, we will evaluate several options.

Cable protection would indeed be nice to have but I do not consider it an essential vital camera feature.
#10
General Chat / Re: Apertus Axiom Beta
October 09, 2014, 09:21:13 AM
Final crowd funding amount: €174,520 EUR

Absolutely incredible, thanks so much everyone here.

I am officially stoked now :)
#11
General Chat / Re: Apertus Axiom Beta
October 08, 2014, 08:57:31 PM
Quote from: ronx on October 08, 2014, 05:12:07 AM
the link on the wiki is not working, so if anyone has a sample and can get it to me (somehow), id very much appreciate it

Hi ronx, the link has been fixed.
#12
General Chat / Re: Apertus Axiom Beta
October 06, 2014, 12:47:44 PM
Quote from: chmee on October 06, 2014, 10:24:11 AM
@Sebastian i remember this design of modular blocks. is it still on your agenda? is this the gamma?
Yes that is on the roadmap for the AXIOM Gamma.
The AXIOM Beta will also be modular with swappable IO shields. But changing modules will be a bit less convenient here - not something you want to do on a daily basis. On the other hand you will not need different outputs every day anyway :)
#13
General Chat / Re: Apertus Axiom Beta
October 05, 2014, 11:10:01 PM
Hurray! Thanks so much everyone!

We couldn't have done it without you!

And that's not just a saying, without the ML community we would have failed!
#14
General Chat / Re: Apertus Axiom Beta
October 03, 2014, 10:30:35 PM
Quote from: Walter Schulz on October 03, 2014, 10:17:30 PM
What happened now, Sebastian?
"Super35, 3rd Batch" not longer there ...
Not delighted about this ...
Cassandra moving in her sleep ...

3rd batch moved to top, now "featured".

Quote from: nikfreak on October 03, 2014, 07:52:13 PM
Now that would be awesome. Btw what OS is Axiom going to use? Some kind of RTOS or even linux?

The AXIOM Alpha prototype uses a custom Linux kernel and a Raspian image in a chroot environment to separate "gimmicks" like the webserver/etc. from the essential "life-support" system.

The current plan for the Beta is to have one core running Arch Linux and the other dedicated for bare metal applications related to the camera functions, or alternatively both cores running Arch.
#15
General Chat / Re: Apertus Axiom Beta
October 01, 2014, 11:47:39 AM
Quote from: chmee on September 30, 2014, 11:24:58 PM
just read an interesting critique. where's an audio-in port? if its possible to encode the mediafile inside the body, it would be useful to give at least an unmanaged line-in to embed it into the file.

regards chmee

1. as we rely on external recorders for video those have the dedicated audio inputs. That way recording audio/video in sync is also guaranteed.

2. We still have the right side IO shield which is not 100% defined interface wise, we only have bandwidth for "slow interfaces" which would include audio, genlock, timecode, trigger, etc.
Since these interfaces are electrically all similar (we will need to look into the details - so far all SMPTE papers we found did not talk about electronic characteristics of the signal at all....) we might just make it user configurable (aka defined in software) what the port does.
#16
General Chat / Re: Apertus Axiom Beta
October 01, 2014, 11:42:33 AM
Guys, you rock! I want to just hug you all  :D

The donations started flowing again - I really hope we will make it!



Yesterday we also announced 16mm sensor options, monochrome sensor options and stretch goals:

------------------------------

https://www.indiegogo.com/projects/axiom-beta-the-first-open-digital-cinema-camera/#activity

edit: having to scroll 5 pages is not fun ;)
#17
General Chat / Re: Apertus Axiom Beta
September 29, 2014, 03:05:59 PM
Many thanks for all the received donations! I really hope together with you we can get the campaign to a successful end!

Quote from: sanderbontje on September 29, 2014, 09:35:32 AM
@Sebastian: Regarding the max fps, is the Axiom's max 60fps out a limitation of the HDMI controller only? In other words, would adding another IO-shield with for instance SDI be an option to reach higher framerate output? Or is the imaging pipeline on Zedboard a limiting factor in this too, capped at 60fps?

Its a limit of the HDMI output, also note that its 60FPS PER port, so if we run the 3 HDMI ports in alternating frame mode we can actually get 180FPS in 1080p.

And yes different IO shields in the future might be able to go much higher with FPS, 3G-SDI (SMPTE 424M) though is also limited to 1080p60 but 6G-SDI might be an option (also dual link maybe), or direct PCIe - we will see what the future brings.
#18
General Chat / Re: Apertus Axiom Beta
September 27, 2014, 05:16:25 PM
Quote from: a1ex on September 27, 2014, 01:27:33 PM
That's really impressive. You mean, it can get 840fps at 1080p lines, and 1900 fps at 480 lines?!

I am not sure if there is any additional limiting factor (like FOT) or if its just max fps = max_lines/read_lines * 300 FPS @10bit

But the increase should be almost linear (it was that way with the Aptina CMOS in Elphel cameras)

update: And yes, just because the sensor can provide those crazy frames per second rate does not mean we can output them. Processing them seems a much more likely option as the entire image pipeline in the AXIOM Alpha already runs in 4K@60FPS and we only downsize in the very last step for the HDMI port which can't handle 4K on the Zedboard.
#19
General Chat / Re: Apertus Axiom Beta
September 27, 2014, 01:12:47 PM
Many thanks for taking the time to measure all this, its indeed very interesting.

About row noise please check the application note from CMOSIS I emailed you (a1ex), they suggest applying a reference voltage to some additional sensor pins and report a significant improvement in row noise behavior.

About PLR:
I also think it can go beyond the officially listed 15 f-stops - I ran tests with +6 F-stops and while the footage was not without flaws in general it worked and definitely looked promising.
I noticed though that color saturation decreases with the amount of PLR highlight recovery and the fixed pattern noise is getting stronger in those areas. Both effects might be possible to compensate in internal image processing. Maybe we can measure/benchmark those settings as well in the future.

Here is a quick +6 stops test where I varied the lens aperture to measure latitude differences before turning on PLR:



PLR HDR vs HDRx:
As I understand it (I have not personally shot any HDRx footage on Red cameras) the differences are:
-) HDRx saves 2 exposure bracketed image streams and you can mix them together with different algorithms in post.
-) PLR HDR combines 2/3 (selectable) exposure brackets and mixes them together based on luminosity threshold on the sensor as the images are gathered already. The output is a single image stream - no post processing required to combine exposures.
-) with PLR highlights loose light sensitivity - shadows keep their light sensitivity - the curve can be tweaked in all aspects.
-) with PLR flickering can occur in highlights created by flickering light (AC tungsten, flickering CRT screens, magnetic ballast fluorescent tubes) as PLR reduces exposure time in highlights, but PLR actually does up to 3 exposure phases in one normal exposure time (not a single short one) so the effect might not be that visible -> will require more tests (I have not seen flickering in any PLR footage I shot yet - but I used PLR tweaking mostly with bright sunlight which will obviously not start to flicker :) )


About max FPS
The CMV12000 V2 can indeed go up to 300 FPS at full 4096x3072 resolution in 10 bit mode, in 12 bit mode this max FPS is reduced to 180 FPS according to official specs. By reducing the number of read rows (smaller window -> e.g. reading a 16x9 window from the 4:3 sensor) the max FPS will increase beyond the 300/180 FPS.


Other Sensors
Canon doesn't sell their sensors, Sony only sells to partners or large volume orders and they only sell a small selection of the sensors, not their latest cinema ones. There are only a few companies who sell large diameter sensors beside the mentioned Kodak/Truesense, Cmosis, Aptina that are OnSemi (VITA12/16/25 series) and dynamax imaging which all offer similar specs for similar prices.
The biggest factor for us though is that the sensor datasheet can be shared without an NDA and that only Cmosis and Truesense agreed to. It is essential that developers and the community have access to this documentation and we will not incorporate any image sensor that has no open documentation. After all these measurements as a1ex did them would have been pretty much impossible otherwise.
#20
General Chat / Re: Apertus Axiom Beta
September 16, 2014, 05:21:01 PM
Sorry for the delay, returned from IBC yesterday night :)

I am located in Vienna.

Another developer would be amazing :)

For still image storage we currently use a custom camera format that basically just writes the raw bits of each pixel in a 16 bit sequence, details about RAW16 as we called it are here: https://wiki.apertus.org/index.php?title=RAW16
There is also the derived format RAW12 which as the name suggests just packs 12bit sequences as the CMV12000 can only go up to 12 bits.
Tuning the image pipeline is definitely some work ahead but hey if we succeed we can do it together and not wait until some company does it for us :)

Some images in RAW16 format are available here: http://vserver.13thfloor.at/Stuff/AXIOM/ALPHA/RAW/

Image Sensor datasheet is on Github: https://github.com/apertus-open-source-cinema/alpha-hardware/tree/master/Datasheets

#21
General Chat / Re: Apertus Axiom Beta
September 10, 2014, 10:12:25 PM
Glad to see you talking about our campaign in here.

If some Magic Lantern users would be willing to support us that would be much appreciated!  :D

I do not see any problems supporting MLV codec on the Beta if there is some interest from users.
In a first stage we focus on the image acquisition part only and so we do external recording only but its just a matter of time until we get to the point to create an internal recording module.
#22
General Chat / Re: Apertus Axiom Beta
May 09, 2014, 10:02:04 AM
Thanks to your work on magic lantern people now understand why an open source firmware is important for filmmakers and the creative potential and technical capabilities of a device.

Countless times I have been asked why DOPs should care about the camera they are using being "open", they say they are not programmers so they wont do anything with the code anyway....

I hope to see many Magic Lantern developers/users in our AXIOM Beta early adopters community. We would love to hear your feedback and incorporate your ideas into the AXIOM Beta hardware/software. Since everything will be open and well documented I know its not as much of a challenge as when you have to blink out and de-compile Canons firmware but maybe it's still fun to focus more on the creative high level features :)
#23
General Chat / Re: Looks like Apertus is selling out
April 02, 2014, 11:31:42 PM
Yeah well the deal was just to good to refuse.

Or wasn't it.... https://apertus.org/2014-lies-lies-lies


Who did we successfully fool? :)
#24
General Chat / Re: Magic Lantern Cinema Camera?
May 31, 2013, 11:04:57 PM
Actually we at apertus° want Axiom (http://axiom.apertus.org/) to be like the ultimate magic lantern camera. A high end camera that can easily be modified by its users for their needs and wishes in every possible aspect.
Just without all the reverse engineering and blinking out and decompiling of firmware as everything related to Axiom will be free/open and well documented. We hope that won't take the fun out of it :)