Abstract: This article briefly introduces the structure of the sound discrimination system, the virtual instrument, and its development environment LabVIEW. The sound acquisition and playback were analyzed and implemented in a computer using LabVIEW. This provides a simple and effective method for sound acquisition and analysis for the sound discrimination system. Practice has proven that this is an effective way to expand the application scope of LabVIEW. Keywords: Virtual Instrument, LabVIEW, sound discrimination The system should first collect the sounds emitted or produced by the target as samples, and then generate an application template for that target through training. Once the template is loaded into the system, the system will automatically capture the corresponding target and prompt the user. It can be deployed on various hardware platforms, so the above system can also be implemented with low-cost hardware. It has a wide range of applications: access control systems, using voice to control the automatic opening of door locks; telephone banking systems, using voice to control transfer passwords; vehicle detection systems, detecting the condition of vehicles based on sound; monitoring systems, listening to whether someone is using a telephone line, particularly suitable for military and national security agencies; measurement systems, using sound to measure the depth of seawater, particularly suitable for exploration departments. [align=center]Basic Principle Diagram of Sound Identification System[/align] 2. Introduction to Virtual Instruments and LabVIEW A virtual instrument is a modular instrument used in conjunction with a PC. It does not have a physical panel; instead, it utilizes the powerful graphics environment and online help functions of the PC to create a graphical "virtual" instrument panel, enabling control, data analysis, and display of the instrument. Users can operate their PCs through a user-friendly graphical interface (Front Panel 1), just like operating a traditional instrument they have defined and designed themselves. Essentially, it organically integrates computer hardware resources with instrument hardware through software, combining the powerful computing capabilities of the computer with the measurement and control capabilities of the instrument hardware. This significantly reduces the cost and size of the instrument hardware, and enables data display, storage, and analysis through software. LabVIEW, developed by National Instruments (NI), is an excellent graphical programming development platform. It stands for Laboratory Virtual Instrument Engineering Workbench and is currently the most widely used and powerful virtual instrument development platform. It has evolved from the original LabVIEW 1.0 to the current LabVIEW 8.2 version, and is now a very sophisticated virtual instrument development platform. Creating virtual instruments using the LabVIEW development platform involves writing graphical programs on the LabVIEW platform. These graphical programs are virtual instrument programs, or VIs for short. A virtual instrument program (VI) consists of two parts: a front panel program and a flowchart program (also known as a block diagram program). Creating a virtual instrument VI in the LabVIEW development platform involves designing the "virtual front panel" and its corresponding "flowchart" program in the "Front Panel Development Window" and "Flowchart Editing Window." The edited flowchart program is represented graphically. The graphical programming approach is consistent with traditional source code programming. To acquire signal data, drivers for I/O interface hardware devices (different types of virtual instruments have different hardware devices, such as DAQ data acquisition cards, GPIB instruments, serial port instruments, VXI instrument modules, etc.) need to be written; to perform calculations and analysis on the acquired signal data, calculation and analysis programs need to be written. LabVIEW can generate independently running executable files; it is a true 32-bit compiler. Like many important software programs, LabVIEW provides versions for Windows, UNIX, Linux, and Macintosh. Because LabVIEW provides users with a simple, intuitive, and easy-to-use graphical programming method, simplifying complex language programming into menu-driven function selection and connecting various functions with lines, it is very time-saving and convenient, making it highly popular among users. Compared with traditional programming languages, LabVIEW graphical programming can save more than 85% of program development time, while its running speed is almost unaffected, demonstrating extremely high efficiency. Using virtual instrument products, users can rebuild new instrument systems according to actual production needs. For example, users can connect existing instruments with RS232 interfaces, VXI bus instruments, and GPIB instruments through a computer to form various new instrument systems, which are then managed and operated uniformly by the computer. 3. Implementing the sound acquisition module of the sound identification system using LabVIEW Due to LabVIEW's efficient programming and its advantage of combining the powerful display, storage, and computing capabilities of the computer with the measurement and control capabilities of the instrument hardware, it has unparalleled advantages in using it to write the acquisition and processing links of the sound identification system compared to other programming languages. (1) Sound acquisition front panel design (2) Program panel design Sound acquisition program design Sound playback program design 4. Conclusion This article describes the concept and development prospects of virtual instruments and briefly introduces the characteristics and usage of LabVIEW. The sound acquisition and playback were implemented using LabVIEW. Due to LabVIEW's powerful data processing capabilities, it has established its advantageous position in the sound acquisition and analysis stage of the sound identification system, thereby improving the application scope of virtual instruments. This method has been implemented in LabVIEW 7 Express for Windows XP. Practice has proven that this method is efficient and easy to implement, and is a good way to expand the application of LabVIEW. 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