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Comment by icelancer | Hacker News Reader

For example (I just emailed Arducam about this):

The IMX477/R sensor supports Full (16:9) Binning 1080P @ 2028(H) × 1128(V) with 240hz/fps availability in a drive mode. However, no IMX477/R package I've ever found - including those from Arducam - support a CSI->USB board or similar that can drive this mode, only allowing 100 FPS maximum on most packages. (ex: https://www.uctronics.com/arducam-high-quality-complete-usb-...)

I am looking to buy a product involving the IMX477/R sensor that can drive this mode or similar 240 FPS modes, but cannot find it for the life of me despite the datasheet openly supporting this drive mode.

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Forget the USB boards, they all work to the best of the USB / UVC limitations but they aren’t great. You want to hook your camera sensor up to a processor with a CSI input.

Image sensors are really just high speed ADC clocking out data, whether the data is useful or not is up to the viewer. What I’m getting at is forget FPS and think data rates.

So, you need a processor that is that can handle that data rate. The napkin math says 2K@240FPS has the same data rate as 4K@60FPS. All you need is a processor or module that can handle it and you’re golden. There are demos of the RPI pushing 1000fps (at a significant lower resolution) but you get the point.

Off the top of my head, NVIDIA jetson, imx8m mini plus, the latest allwinner V series, and a whole host of unobtainable in less than 10k qty parts all supported this. The rest is up to you.

Also, RPi is out even with 4 lanes because the CSI input doesn’t support the speed required on each lane.

You seem knowledgeable in this area. Do you know how image sensor support works? Can you attach any camera with CSI to the SBCs that you listed?

Short answer - No. The MIPI CSI-2 (CSI has been deprecated) interface is not plug and play. It requires some tuning of the handshaking between the image sensor and the receiving SOC. I think the RPI + HQ camera + libcamera is the best place to start to learn a full camera system since libcamera is open source. The software stack for a camera is a pretty large undertaking. The ISP calibration and AAA algorithms are generally closely held by various camera companies.

I've written raw frames to memory using the RPi HQ cam and RPi4 and processed them in ffmpeg/dcraw for example, so I'm familiar with that methodology. I can take it from there if I can find an IMX477 sensor (or similar) plus 4+ MIPI lanes to get full drive mode.

Any idea where to start? I am proficient enough in scripting/coding to pick up a new platform like the Jetson/Nvidia products, but no idea where to find the correct sensor+board package to actually give me the data rates I need.

Looking for 240fps/hz @ 720p in some form of greyscale, for the record.

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