Gansu non-coal mine electronic seal smart coal mine is connected to the national mine safety platform through the python+opencv network model, Gansu non-coal mine electronic seal python+opencv network model for key positions (return air wellhead, transporting people wellhead, vehicle entrance and exit) to the site The data of personnel behavior, quantity, clothing and equipment status are monitored and analyzed in real time. Python translates the program into machine language when it is running; programs in interpreted languages do not need to be compiled before running, but are translated when the program is running. A special interpreter is responsible for interpreting the program code when each statement is executed, so An interpreted language needs to be translated every time it is executed, and there is a compiled language corresponding to it. OpenCV is implemented based on C++ and provides interfaces for languages such as python, Ruby, and Matlab. OpenCV-Python is OpenCV's Python API, which combines the best features of OpenCV C++ API and Python language. OpenCV is available on different system platforms including Windows, Linux, OS, X, Android and iOS. High-speed GPU operation interfaces based on CUDA and OpenCL are also under active development.
OpenCV-Python is a library of Python bindings designed to solve computer vision problems. Python is a general-purpose programming language developed by Guido van Rossum, which quickly became very popular mainly because of its simplicity and code readability. It enables programmers to express ideas in fewer lines of code without loss of readability.
Python is slow compared to languages like C/C++. That said, Python can be easily extended using C/C++, which allows us to write computationally intensive code in C/C++ and create Python wrappers that can be used as Python modules. This gives us two benefits: first, the code is as fast as raw C/C++ code (since it's actual C++ code working behind the scenes), and second, it's easier to write code in Python than in C/C++. OpenCV-Python is a Python wrapper around the original OpenCV C++ implementation. OpenCV-Python uses Numpy, a highly optimized database manipulation library with MATLAB-style syntax. All OpenCV array structures are converted to Numpy arrays. This also makes it easier to integrate with other libraries that use Numpy, such as SciPy and Matplotlib.
The Adapter interface defines the following methods:
public abstract void registerDataSetObserver (DataSetObserver observer)
Adapter represents a data source. This data source may change, such as adding data, deleting data, and modifying data. When the data changes, it must notify the corresponding AdapterView to make corresponding changes. In order to realize this function, the Adapter uses the observer mode. The Adapter itself is equivalent to the observed object, and the AdapterView is equivalent to the observer. Register the observer for the Adapter by calling the registerDataSetObserver method.
public abstract void unregisterDataSetObserver (DataSetObserver observer)
Unregister the observer by calling the unregisterDataSetObserver method.
public abstract int getCount () returns the number of data in the Adapter.
public abstract Object getItem (int position)
The data in the Adapter is similar to an array, and each item in it corresponds to a piece of data, and each piece of data has an index position, that is, position, and the corresponding data item in the Adapter can be obtained according to the position.
public abstract long getItemId (int position)
Get the id of the specified position data item, usually the position will be used as the id. In Adapter, relatively speaking, position is used more frequently than id.
public abstract boolean hasStableIds ()
hasStableIds indicates whether the id of the original data item will change when the data source changes. If it returns true, it means the Id remains unchanged, and if it returns false, it means it may change. The hasStableIds method of Adapter subclasses (including direct subclasses and indirect subclasses) provided by Android all return false.
public abstract View getView (int position, View convertView, ViewGroup parent)
getView is a very important method in Adapter, which will create corresponding UI items for AdapterView according to the index of the data item.