Hi,
We are working in a project using Xavier NX and latest Jetpack. The original input resolution coming from the camera is 12,000 x 9,000 (4.5Gbps per MIPI CSI lane). Since this frame is too big for Jetson, the customer will split the big frame in two halves (6000x9000) and lower the frequency to 2.5Gbps to match Xavier specs.
I read that on TX2, it is possible to use the Gang mode (Multi-brick streams) and suggested here too, and it was tested with 8 lanes and TC358840 (most of the posts in 2018/19).
Questions:
- Is it possible to use the Multi-brick mode in Jetson Xavier NX?
- If so, would VI reconstruct the original frame?
- Does VI pass the frame through the ISP for Debayering in this case?
- For this cases, is Bayer or YUV required in the MIPI CSI inputs?
- How is Jetson able to reconstruct the big frame? Is there a risk to get half of an old frame and half of a newer frame?
Thanks,
-David
hello DavidSoto-RidgeRun,
please check this, Ganged mode does not work with HDMI input via CSI - #5 by JerryChang
Multi-brick streams (i.e. gang mode) is NOT implemented for Xavier series VI driver.
there’s limitation for the CSI bandwidth, 40-Gbps (2.5Gbps/lane) in DPHY; CPHY will have larger bandwidth, 109-Gbps.
regarding to the ISP capability, it has the max line buffer width as 6144.
Hi Jerry, Thanks the quick question and the information provided. We will pass the information to the customer. If this were on TX2 or Nano, what would be the answers to the questions?
hello DavidSoto-RidgeRun,
all these three Jetsons (Nano, TX2, Xavier series) has the same ISP capability, the max line buffer width as 6144.
you may also check TRM for the detail of CSI bandwidth,
for example,
DPHY: Nano, 1.5-Gbps/lane; TX2: 1.875-Gbps/lane; Xavier: 2.5-Gbps/lane.
CPHY: Nano, NA; TX2: 41-Gbps; Xavier 109-Gbps.
if you check into VI’s driver, you’ll see both VI-2 and VI-4 drivers had implementation for gang modes.
thanks