hi_isp_ae_route_ex_node

Description

Defines the attribute of the node on the extended AE route.

Definition

typedef struct {
    hi_u32  int_time;
    hi_u32  a_gain; 
    hi_u32  d_gain; 
    hi_u32  isp_d_gain; 
    hi_isp_iris_f_no  iris_fno; 
    hi_u32  iris_fno_lin;  
} hi_isp_ae_route_ex_node;

Members

Restrictions

• The node exposure is the product of the exposure time, sensor analog gain, sensor digital gain, ISP digital gain, and iris. The node exposure is monotonically increasing. To be specific, the exposure of a node is greater than or equal to that of the previous node. The exposure of the first node is the lowest, and the exposure of the last one is the highest. During exposure calculation, the f-number of the iris needs to be converted into the equivalent gain as follows: Equivalent gain FNO = 1 <<HI_ISP_IRIS_F_NO_XX_XX. In other words, F32.0 corresponds to gain 1, F22.0 corresponds to gain 2, and F16.0 corresponds to gain 4. As the rule applies, F1.0 corresponds to gain 1024.

• fno_ex_valid in hi_isp_piris_attr can be configured to determine whether iris_fno or iris_fno_lin is used as the iris value of the extended AE route node that actually takes effect. If fno_ex_valid is HI_TRUE, the high-precision iris_fno_lin will be used. iris_fno is used by default. iris_fno is restricted by max_iris_fno_target/min_iris_fno_target in hi_isp_piris_attr, and iris_fno_lin is restricted by max_iris_fno_target/min_iris_fno_target in hi_isp_piris_attr. In addition, iris_fno and iris_fno_lin are restricted by max_iris_fno/min_iris_fno in hi_isp_ae_sensor_default. Therefore, you need to assign a proper value to max_iris_fno/min_iris_fno in cmos.c when the P-Iris is connected.

• The nodes cannot be configured to have the same exposure.
• To ensure the exposure of the exposure node, when one component of the exposure node is restricted, other components that have not reached the maximum value will be adjusted. The route that takes effect may be inconsistent with the configured route.
• If the exposure of adjacent nodes increases, the value of a component should increase while the values of other components remain unchanged. The component with an increased value determines the allocation policy of the route. For example, if the value of the sensor analog gain component increases, the allocation policy of the route is sensor analog gain-first (the sensor analog gain is allocated first).
• Only the P-Iris is supported. The DC-iris is not supported, because it cannot be accurately controlled.
• For the P-Iris, you are advised to set the exposure time, gain, and iris f-number of the first node to the corresponding minimum target values, and set those of the last node to the corresponding maximum target values.
• The node exposure time cannot be set to 0 or too small. Otherwise, the number of exposure lines corresponding to the exposure time in μs is 0, and an exception may occur.
• The node gain range for the extended AE route is smaller than that for the common AE route. In addition, to prevent overexposure, the 10-bit system gain equivalent to the product of the sensor analog gain, sensor digital gain, and ISP digital gain cannot be greater than 0xFFFFFFFF. The maximum product value of the exposure time and system gain of 10-bit precision of a node cannot exceed 0x1FFFFFFFFFFFFF if the iris component is enabled, and cannot exceed 0x7FFFFFFFFFFFFFFF if the iris component is disabled.
• If the allocation policy of a route needs to be set to ISP digital gain-first, you are advised not to set the ISP digital gain to the maximum value because the ISP digital gain needs to be used to compensate for allocation precision. It is recommended that a margin of at least 1/2 of the maximum ISP digital gain be reserved for precision compensation. To be specific, Isp_d_gain of the node on the allocation route cannot be greater than max_Isp_d_gain/2.
• When the gains can be separately configured, some ISP digital gains in the exposure node may be allocated to WDRGain.