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Published equation contexts

Rframe=Npixels⋅fframe⋅b,Revent(t)≈Nactive(t)⋅beventR_{\mathrm{frame}} = N_{\mathrm{pixels}} \cdot f_{\mathrm{frame}} \cdot b, \qquad R_{\mathrm{event}}(t) \approx N_{\mathrm{active}}(t) \cdot b_{\mathrm{event}}

Why this formula appears here

Commercial event sensors have reached production stacked-silicon form. The Sony-Prophesee IMX636 reports pixel latency under 100 microseconds at 1,000 lux, standby power of 5 milliwatts against a maximum of 205 milliwatts, and a peak event rate above one billion events per second across its 1,280-by-720 array [ 13 ] . Because a pixel only ever transmits when it individually crosses its change threshold, the sensor’s data rate scales with how much of the scene is actually changing, not with the pixel count or a fixed frame clock — the opposite dependency from a frame sensor’s fixed-rate readout: Rframe=Npixels⋅fframe⋅b,Revent(t)≈Nactive(t)⋅beventR_{\mathrm{frame}} = N_{\mathrm{pixels}} \cdot f_{\mathrm{frame}} \cdot b, \qquad R_{\mathrm{event}}(t) \approx N_{\mathrm{active}}(t) \cdot b_{\mathrm{event}}. where Nactive(t)N_{\mathrm{active}}(t) , the number of pixels crossing threshold at a…

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RframeR_{\mathrm{frame}}

Symbol R_frame

RfR_frame is part of the quantity the equation computes from the expression on the right.

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NpixelsN_{\mathrm{pixels}}

Symbol N_pixels

NpN_pixels is one factor in the product that computes the quantity on the left.

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fframef_{\mathrm{frame}}

Symbol f_frame

fff_frame is one factor in the product that computes the quantity on the left.

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ReventR_{\mathrm{event}}

Symbol R_event

ReR_event is one factor in the product that computes the quantity on the left.

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NactiveN_{\mathrm{active}}

Symbol N_active

NaN_active is one factor in the product that computes the quantity on the left.

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beventb_{\mathrm{event}}

Symbol b_event

beb_event is one factor in the product that computes the quantity on the left.

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Published contexts (1)

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Rframe=Npixels⋅fframe⋅b,Revent(t)≈Nactive(t)⋅beventR_{\mathrm{frame}} = N_{\mathrm{pixels}} \cdot f_{\mathrm{frame}} \cdot b, \qquad R_{\mathrm{event}}(t) \approx N_{\mathrm{active}}(t) \cdot b_{\mathrm{event}}

Equation 7 · Edge AI & Electronics

Comparing the Main Approaches to Edge AI Electronics and Sensor Systems

This equation gives an approximation: it relates the quantities while allowing an approximation.

Commercial event sensors have reached production stacked-silicon form. The Sony-Prophesee IMX636 reports pixel latency under 100 microseconds at 1,000 lux, standby power of 5 milliwatts against a maximum of 205 milliwatts, and a peak event rate above one billion events per second across its 1,280-by-720 array [ 13 ] . Because a pixel only ever transmits when it individually crosses its change threshold, the sensor’s data rate scales with how much of the scene is actually changing, not with the pixel count or a fixed frame clock — the opposite dependency from a frame sensor’s fixed-rate readout: Rframe=Npixels⋅fframe⋅b,Revent(t)≈Nactive(t)⋅beventR_{\mathrm{frame}} = N_{\mathrm{pixels}} \cdot f_{\mathrm{frame}} \cdot b, \qquad R_{\mathrm{event}}(t) \approx N_{\mathrm{active}}(t) \cdot b_{\mathrm{event}}. where Nactive(t)N_{\mathrm{active}}(t) , the number of pixels crossing threshold at a…

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