Multi-camera dynamic synchronous exposure circuit and method of FPGA-based photogrammetry system

Abstract

The invention discloses a multi-camera dynamic synchronous exposure circuit and method for an FPGA-based photogrammetry system. The circuit includes a forward channel module, an FPGA processing module, a power supply module and a clock module, wherein: the forward channel module provides connections for each camera The channel is connected to the FPGA processing module at the same time, and transmits the camera trigger commands collected by each camera; the FPGA processing module records the asynchronous time difference of the shutter action of each camera according to the acquired camera trigger commands, and calculates the value of the synchronization time difference, according to the synchronization time difference Value, based on the shutter action signal that arrives last, delay other trigger signals to generate synchronous camera trigger signals for each camera; the power supply module provides power for the FPGA processing module, and the clock module is configured to provide high-frequency timing for the FPGA processing module base clock signal.

Description

technical field [0001] The invention relates to an FPGA-based photogrammetry system multi-camera dynamic synchronous exposure circuit and method. Background technique [0002] If a single digital camera is used as the main sensor for image acquisition in mobile photogrammetry, the acquired digital images have a series of problems such as small image size, large number of images, long processing time, short baseline, and low elevation accuracy. Although some units at home and abroad, such as the Chinese Academy of Surveying and Mapping Sciences, have developed SWDC aerial survey cameras and special wide-angle combination cameras for UAVs, DMC aerial survey cameras in the United States, and UCD aerial survey cameras in Austria, there are still problems such as high price, large size, complex structure, and weight. Heavy and other issues. [0003] The emergence of multi-camera systems has been widely used. Compared with single cameras, multi-camera systems can obtain more accu...

AI Technical Summary

Problems solved by technology

[0004] Traditional synchronization is that multiple cameras use the same synchronization pulse to control simultaneous exposure, without considering the mechanical differences of each camera, and the time and space of the exposure synchronization error of each camera caused by factors such as temperature, humidity and air pressure in a complex working environment. Dispersion, etc., resulting in the synchronous exposure error of this method is about 10mS, and it is impossible to achieve high-precision synchronous exposure within the microsecond level

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