CN-121985111-A - Multi-camera photographing synchronization judging method and device and computer readable storage medium

CN121985111ACN 121985111 ACN121985111 ACN 121985111ACN-121985111-A

Abstract

A synchronization judging method and device for photographing of multiple cameras and a computer readable storage medium are provided, wherein the synchronization judging method comprises the steps of acquiring image frames acquired by N cameras respectively, sending photographing trigger signals received by the N cameras at the same time, determining a target row of each image frame, acquiring pixel rows acquired when the state of an external light source of the target row is changed, and determining whether N image frames are synchronous or not based on the target row of each image frame. According to the scheme, whether the images shot by the multiple cameras are synchronous or not can be accurately judged.

Inventors

WU DONGHUI
WANG CHAO
CHEN JINFENG

Assignees

黑芝麻智能科技有限公司

Dates

Publication Date: 20260505
Application Date: 20260130

Claims (11)

1. A synchronous judging method for photographing by a multi-camera is characterized by comprising the following steps: acquiring image frames acquired by N cameras respectively, wherein photographing trigger signals received by the N cameras are transmitted at the same time, N is a positive integer and is more than or equal to 2; Determining a target row of each image frame, wherein the target row is a pixel row acquired when the state of an external light source is changed; based on the target line of each image frame, it is determined whether the N image frames are synchronized.
2. The synchronization judging method of claim 1, wherein the target line comprises at least one of: the external light source is switched from the off state to the first pixel row acquired when the external light source is switched from the on state to the off state.
3. The synchronization judging method according to claim 2, wherein the target line of the i-th image frame of the N image frames is determined by: The characteristic value of any pixel row comprises any one of the average brightness value of the corresponding pixel row and the average color temperature value of the corresponding pixel row; acquiring a difference value between the characteristic value of each pixel row and the characteristic value of the next adjacent pixel row; determining a pixel row with the largest characteristic value in the two pixel rows with the largest difference of the characteristic values as the target row; and/or determining the pixel row with the smallest characteristic value of the two pixel rows with the smallest characteristic value difference as the target row.
4. The method for synchronizing the image frames according to claim 3, wherein the resolution of each of the different image frames is the same, wherein determining whether the N image frames are synchronized based on the target line of each of the image frames comprises: acquiring a line number of a target line of each of the N image frames; determining that the line number difference of the target line of any two image frames is not larger than a preset first difference value, and determining that the N image frames are synchronous; and determining that the N image frames are not synchronous when the difference of the line numbers of the target lines corresponding to at least two image frames is larger than the first difference.
5. The method for synchronizing the image frames according to claim 3, wherein the resolution of each of the different image frames is the same, wherein determining whether the N image frames are synchronized based on the target line of each of the image frames comprises: determining the position of an extreme point of a characteristic value corresponding to an ith target row based on the ith target row, a previous row of the ith target row and a next row of the ith target row; Determining that the difference between positions of extreme points corresponding to any two image frames is not larger than a preset second difference value, and synchronizing the N image frames; and determining that the N image frames are not synchronous when the difference between the positions of the extreme points corresponding to the at least two image frames is larger than the second difference.
6. The synchronization judging method according to claim 3, wherein a resolution of a first image frame of the N image frames is different from a resolution of a second image frame; the determining whether the N image frames are synchronized based on the target line of each image frame includes: determining a first moment point based on a target line of the first image frame, wherein the first moment point is associated with a longitudinal resolution corresponding to the first image frame; determining a second moment point based on a target line of the second image frame, wherein the first moment point is associated with a longitudinal resolution corresponding to the second image frame; And determining that the first image frame is synchronous with the second image frame in response to the time difference between the first time point and the second time point being smaller than a preset synchronization judging threshold value.
7. The synchronization judging method according to any one of claims 1to 6, wherein the N cameras are rolling shutter cameras, and frame rates of the N cameras are the same.
8. The synchronization judging method of claim 7, wherein the photographing trigger signals received by the N cameras are the same photographing trigger signal, or the photographing trigger signals received by the N cameras are transmitted at the same time.
9. The utility model provides a synchronous judgement device that multiphase camera was photographed which characterized in that includes: the device comprises an acquisition unit, a display unit and a display unit, wherein the acquisition unit is used for acquiring image frames acquired by N cameras respectively, and shooting trigger signals received by the N cameras are transmitted at the same moment, wherein N is a positive integer and is more than or equal to 2; A determining unit configured to determine a target line of each image frame, the target line being a line of pixels acquired when a state of an external light source is changed; And the judging unit is used for determining whether N image frames are synchronous or not based on the target line of each image frame.
10. A computer readable storage medium, the computer readable storage medium being a non-volatile storage medium or a non-transitory storage medium, on which a computer program is stored, characterized in that the computer program when executed by a processor performs the steps of the synchronization judging method for multi-camera shooting according to any one of claims 1 to 8.
11. The synchronization judging device for multi-camera shooting comprises a memory and a processor, wherein a computer program capable of running on the processor is stored in the memory, and the synchronization judging device is characterized in that the processor executes the steps of the synchronization judging method for multi-camera shooting according to any one of claims 1-8 when running the computer program.

Description

Multi-camera photographing synchronization judging method and device and computer readable storage medium Technical Field The present invention relates to the field of image processing technologies, and in particular, to a synchronization judging method and apparatus for photographing with multiple cameras, and a computer readable storage medium. Background The multi-camera system comprises a plurality of cameras distributed at different positions, and images in respective corresponding fields of view are respectively acquired and processed accordingly. The multi-camera system is widely applied to scenes such as automatic driving, industrial automatic detection, virtual reality, augmented reality, sports event motion capture and the like. From the perspective of data fusion and three-dimensional reconstruction, multi-camera systems typically need to capture image information of a target object from different perspectives, and then fuse these multi-perspective data to construct a complete, accurate three-dimensional model or scene. Taking the field of automatic driving as an example, multiple cameras deployed around a vehicle need to capture environmental information such as roads, vehicles, pedestrians, and the like at the same time. Only if the cameras are highly synchronized in time, it is ensured that the acquired images correspond exactly in the time dimension. Currently, to ensure the time-wise high synchronization of the cameras, the same photographing trigger signal is sent to different cameras to trigger the different cameras to photograph. However, images acquired by different cameras may not be synchronized, given that different cameras have different processing delays. Disclosure of Invention The invention aims at providing a synchronous judging method and device for shooting by a multi-camera and a computer readable storage medium, which can accurately judge whether images shot by the multi-camera are synchronous or not. The invention provides a synchronous judging method for photographing of multiple cameras, which comprises the steps of obtaining image frames respectively collected by N cameras, sending photographing trigger signals received by the N cameras at the same time, determining a target row of each image frame, collecting pixel rows when the state of an external light source of the target row is changed, and determining whether N image frames are synchronous or not based on the target row of each image frame. And acquiring the image frames acquired by the N cameras respectively, acquiring corresponding target rows from each image frame, and further determining whether the N image frames are synchronous or not based on the target rows of each image frame. Therefore, whether the image frames acquired by different cameras are synchronous or not can be accurately determined. Optionally, the target line includes at least one of a first pixel line collected when the external light source is switched from the off state to the on state, and a first pixel line collected when the external light source is switched from the on state to the off state. Optionally, the target line of the ith image frame in the N image frames is determined by acquiring a characteristic value of each pixel line in the ith image frame, wherein the characteristic value of any pixel line comprises any one of a brightness average value of corresponding pixel lines, a color temperature average value of corresponding pixel lines, a difference value between the characteristic value of each pixel line and the characteristic value of the adjacent next pixel line, determining the pixel line with the largest characteristic value in two pixel lines with the largest difference value of the characteristic values as the target line, and/or determining the pixel line with the smallest characteristic value in two pixel lines with the smallest difference value of the characteristic values as the target line. The method comprises the steps of obtaining line numbers of target lines of each of N image frames, determining that the N image frames are synchronous, determining that the difference of the line numbers of the target lines of any two image frames is not larger than a preset first difference value, determining that the N image frames are synchronous, and determining that the difference of the line numbers of the target lines of at least two image frames is larger than the first difference value. The method comprises the steps of determining whether N image frames are synchronous or not based on target rows of each image frame, determining positions of extreme points of feature values corresponding to the ith target row based on the ith target row, a previous row of the ith target row and a next row of the ith target row, determining the positions of the extreme points of the feature values corresponding to the ith target row, determining that the difference of the positions of the extreme points corresponding to any two image fra