AXIOM Beta

1 Printed Circuit Boards

Boards:

• 

  Beta CMV12K THT Sensor Board

• 

  Beta CMV12K ZIF Sensor Board

• 

  Beta Interface Dummy Board

• 

  Beta Main Board

• 

  Beta Power Board

• 

  Beta HDMI Plugin Module

The AXIOM Beta uses a Microzed as main image processing platform:

AES-Z7MB-7Z020-SOM-G

Interface Shield 1

2 AXIOM Beta Generations

Voucher holders get at-cost hardware upgrades and replacements. But any voucher holder can decide it which stage to actually acquire the current AXIOM Beta hardware. Software upgrades are and will always be free and publicly available. You can at any time upgrade or downgrade your camera software.

2.1 AXIOM Beta I - Developer Edition (Early Beta)

Intended for developers and early adopters - first generation that will be shipped - small production batch size of around 20 cameras.

Limitations:

• no enclosure yet - skeleton only (3D View)
• CMV12000 image sensor only
• passive sensor cooling only
• passive E-Mount only (passive Canon / Nikon adapter available)
• screw on UV/IR cut off filter instead of camera internal one
• Interface Board limits image sensors throughput to 150FPS@4K (faster Interface Board replacement will be available later)
• Dual 5V 3A AC power supply only
• 1x HDMI 1080p60 output module and PMOD debug module are the only plugin modules available currently (AXIOM Beta has two slots)
• Solder-on area on AXIOM Main Board not populated with gyroscopes/magnetometer/accelerator yet (will be available later on)
• Power Board requires manual reconfiguration (trimmers) switching to a different image sensor module
• no power switch on camera yet (camera turns on when power is connected)

3 AXIOM Beta Topics

3.1 Active Battery Mount

Battery mount for NP-F970/F750/F550 batteries to power the AXIOM Beta. Includes power usage and capacity monitoring to estimate remaining charge and time remaining.

More Thoughts on Power.

3.1.1 InfoLithium Protocol

Proprietary protocol from Sony that exchanges metadata between batteries and devices. Expected data inside the protocol includes: charge cycles, battery ID, remaining total capacity, remaining current capacity, etc. Only official Sony batteries incorporate this protocol, cheap replacement parts don't and some Pro Sony cameras refuse operation with batteries without InfoLithium communication. Decrypting this protocol could give us more insight into the battery but is not essential as we can measure the discharge curve and estimate remaining capacity rather accurately that way.

3.1.1.1 Hacking References

http://randybuildsthings.wordpress.com/2013/02/25/sony-infolithium-m-teardown/

http://www.dpreview.com/forums/post/4296759

3.2 AXIOM Remote

Still in concepting phase of development.

https://apertus.org/axiom-remote

AXIOM_Remote

3.3 Image Processing Pipeline

Draft pipeline taken from AXIOM Alpha for now.

Image Acquisition Pipeline:

HDMI Image Processing Pipeline:

3.3.1 Image Processing Nodes

3.3.1.1 Debayering

A planned feature is to generate this FPGA code block with "dynamic reconfiguration" meaning that the actual debayering algorithm can be replaced at any time by loading a new FPGA binary block at run-time. This tries to simplify creating custom debayering algorithms with a script like programming language that can be translated to FPGA code and loaded into the FPGA dynamically for testing.

3.3.1.2 Image Overlays

Full HD framebuffer that can be altered from the Linux userspace and is automatically "mixed" with the real time video from the image sensor. (https://www.apertus.org/pong-project on the AXIOM Alpha was implemented exactly with this method)

We still need to decide if a color palette here is sufficient or how many colors we would need. 32 bit image with Alpha channel might be an unnecessary overkill here.

This feature could also be used to draw live histograms/scopes.

3.3.1.3 Peaking

Peaking marks high image frequency areas with colored dot overlays. These marked areas are typically the ones "in-focus" currently so this is a handy tool to see where the focus lies with screens that have lower resolution than the camera is capturing.

Handy Custom Parameters:

• color
• frequency threshold

Potential Problems:

• there are sharper and softer lenses so the threshold depends on the glass currently used. For a sharp lens the peaking could show areas as "in-focus" if they actually aren't and for softer lenses the peaking might never show up at all because the threshold is never reached

3.3.1.4 Image Blow Up / Zoom

Digital zoom into the center area of the image to check focus.

As extra feature this zoomed area could be moved around the full sensor area.

This feature is also related to the "Look Around" where the viewfinder sees a larger image area than is being output to the clean-feed.

This re-sampling method to scale up/down an image in real-time can be of rather low quality (nearest neighbor/bilinear/etc.) as it is only for preview purposes.

3.3.1.5 Matrix and LUTs

3x3 / 4x4 Matrix

AXIOM Alpha uses one LUT per color channel.

Maybe a 3D LUT (17×17×17) is possible at a later point: http://en.wikipedia.org/wiki/3D_lookup_table

3.4 Lens Mounts

AXIOM Beta is outfitted with an E Mount currently. Adapters for Canon, Nikon, PL, etc are widely available.

Picture of Nikon F bayonet mount components.

Mount	Nikon F		Canon EF		Micro Four Thirds
Type	Bayonet
Compatible Lenses	Nikkor FX	Nikkor DX	EF	EF-S (optionally)
Image Circle Size	Full Frame ø 43.3 mm	DX ø 28.4 mm	Full Frame ø 43.3 mm	Canon APS-C ø 27.3 mm	"Half Frame" ø 21.6 mm
Throat	44 mm		54 mm		~38 mm
Flange focal distance	46.5 mm		44 mm		19.25 mm
Axiom Beta Sensor Compatibility	16mm Four Thirds Super35				16mm Four Thirds

More Details: Lens Mounts

3.4.2 Passive Nikon F-Mount

Measured Bayonet Thickness: 1.3mm

3.5 4K RAW PC recording option

This has been renamed to "AXIOM Bridge" and is currently still in the concept phase of development.

3.6 Enclosure Design

Notes:

Body Design Options

Cooling

Switchable ND Filters not planned currently

3.6.1 Skeleton

https://github.com/apertus-open-source-cinema/beta-hardware/tree/master/Enclosure/Skeleton_E-mount

3.7 Electronics

3.7.1 AXIOM Beta PCB Stack Concept

Version 4:

All dimensions are still not final! Work in progress...

File:PCB Stack Concept V03 02.pdf

3.7.2 Image Sensor Frontend

It is planned to incorporate a glass filter slot between lens mount and lens base for placing an IR-cut-off filter or OLPF with IR-cut-off coating in the light path.

for Truesense KAC12040

Dimensions (inches if not stated otherwise):

3.7.2.1 Image Sensors

Graphic that compares the different Sensor Sizes and Lens Image Circles of the Axiom Beta

Axiom Beta Model	16mm	Four Thirds	Super35
Brand	CMOSIS	ON Semionductor (prev. Truesense/Kodak)	CMOSIS
Model	CMV2000	KAC12040	CMV12000
Type	CMOS
Shutter Type	Pipelined Global Shutter	Global & Rolling Shutter	Pipelined Global Shutter
Color filter Array	Bayer (Color model) None (B/W model)
IR filter	no
Anti-Aliasing Filter (OLPF)	no
Size	10.6 mm × 5.94 mm ø 12.1 mm	18.8 mm × 14.1 mm ø 23.5 mm	22.5 mm × 16.9 mm ø 28.2 mm
Crop Factor	Full Frame ∕ 3.56 16mm Film ∕ 1.05	Full Frame ∕ 1.84 Four Thirds ∕ 0.96	Full Frame ∕ 1.54 Super35 ∕ 1.10
Aspect Ratio	16:9	4:3	4:3
Pixel Resolution (h × v)	1920 × 1080	4000 × 3000	4096 × 3072
Pixel Size	5.5 µm	4.7 µm	5.5 µm
Dynamic Range	10 stops 15 stops (HDR mode)	9.3 stops (Gobal Shutter) 12 stops (Rolling Shutter)	10 stops 15 stops (HDR mode)
Sensitivity		200 ISO	~ 400 - 1250 ISO
Max Frame Rate @ Bit Depth	340 fps @ 10 bit 70 fps @ 12 bit	110 fps @ 8 bit 70 fps @ 10 bit 30 fps @ 12 bit 10 fps @ 14 bit	300 fps @ 10 bit 180 fps @ 12 bit
More info	Official Specs	Datasheet	Datasheet Official Specs Sensor Noise Analysis

3.7.3 Shields

The Axiom has 2 medium speed IO interfaces to be used with "shields".

• One 200Mbit/s shield interface
• One 1Gbit/s shield interface
• Not hot pluggable

3.7.3.1 Triple HDMI Output Shield

Each port can deliver an independent 1080p60 4:4:4 stream with a different set of image processing nodes applied. Typically there will be one complete image processing pipeline and the three HDMI ports will output the real time image data from specific points in that processing pipeline.

3.7.3.2 Dual Micro SD Shield

This module adds two micro SD card slots to the AXIOM Beta. The active slot can be switched via the card driver and both cards share a 50MByte/s interface to the Zynq.

The bandwidth is not sufficient for video recording but more than enough for storing full resolution 4K raw still images.

The external slots can not be used for initial booting of the camera.

PCB Top	PCB Bottom

3.7.4 Modules

There are also 2 high speed IO interfaces where "modules" can be hot plugged

• 6.2Gbit/s each:
  • 6 ✕ 950Mbit/s
  • 500MBit/s GPIO
• Two modules can be combined in one 12.4 Gbit/s double height module
• Hot pluggable
• PCIe connector (not using PCIe signaling)

3.8 Beta Naming Scheme

Versions of the AXIOM Beta will be named AXIOM Beta plus the according roman number.

eg. AXIOM Beta I - Developer Edition