How does HTML video tag prevent users from downloading videos?
How to prevent downloading HTML5 videos from web pages?
Many websites want to protect their video content and prevent users from downloading at will. This article explores how a website prevents users from passing HTML5<video></video>
Tag download videos, and the technical principles behind them.
Recently, when I tried to use the browser plug-in to download B station videos, I found that even if I got the MP4 video link, I could not download it directly. The browser prompted "The file cannot be extracted from the website", and only HTML files were saved. Further investigation found that the video link needs to contain the correct Referer information, otherwise the server will return a 403 error. This reveals how the website restricts video downloads.
<video></video>
The tag itself does not have the function to prevent downloading. The mechanism for blocking downloads mainly depends on server-side configuration and front-end JavaScript code. Specific methods include:
Server-side Referer verification: The server will check the Referer field in the HTTP request header. If the Referer information does not meet expectations (for example, not from the website), the server will deny access, returning a 403 error. This is a common anti-theft chain mechanism.
Front-end JavaScript restrictions: Websites may use JavaScript code to disable the right-click menu, hide or modify the video URL, or dynamically generate video playback links to increase the difficulty of downloading.
Video encryption and dynamic loading: Some websites use video encryption technology, or through dynamic loading technology, making the real URL of the video difficult to obtain, thereby preventing direct downloading.
While these methods can effectively prevent most download behaviors, some professional video downloading tools or plug-ins may still bypass these limitations. The author tried to use parsing tools and found some high-definition video links, but due to the lack of appropriate tools, it was ultimately unable to download successfully.
In summary, preventing users from downloading videos is not<video></video>
The function of the tag itself is the result of the joint action of server-side and front-end technologies. To download protected videos, you may need to use special tools or plug-ins.
The above is the detailed content of How does HTML video tag prevent users from downloading videos?. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics











Measuring thread performance in C can use the timing tools, performance analysis tools, and custom timers in the standard library. 1. Use the library to measure execution time. 2. Use gprof for performance analysis. The steps include adding the -pg option during compilation, running the program to generate a gmon.out file, and generating a performance report. 3. Use Valgrind's Callgrind module to perform more detailed analysis. The steps include running the program to generate the callgrind.out file and viewing the results using kcachegrind. 4. Custom timers can flexibly measure the execution time of a specific code segment. These methods help to fully understand thread performance and optimize code.

Using the chrono library in C can allow you to control time and time intervals more accurately. Let's explore the charm of this library. C's chrono library is part of the standard library, which provides a modern way to deal with time and time intervals. For programmers who have suffered from time.h and ctime, chrono is undoubtedly a boon. It not only improves the readability and maintainability of the code, but also provides higher accuracy and flexibility. Let's start with the basics. The chrono library mainly includes the following key components: std::chrono::system_clock: represents the system clock, used to obtain the current time. std::chron

The main steps and precautions for using string streams in C are as follows: 1. Create an output string stream and convert data, such as converting integers into strings. 2. Apply to serialization of complex data structures, such as converting vector into strings. 3. Pay attention to performance issues and avoid frequent use of string streams when processing large amounts of data. You can consider using the append method of std::string. 4. Pay attention to memory management and avoid frequent creation and destruction of string stream objects. You can reuse or use std::stringstream.

DMA in C refers to DirectMemoryAccess, a direct memory access technology, allowing hardware devices to directly transmit data to memory without CPU intervention. 1) DMA operation is highly dependent on hardware devices and drivers, and the implementation method varies from system to system. 2) Direct access to memory may bring security risks, and the correctness and security of the code must be ensured. 3) DMA can improve performance, but improper use may lead to degradation of system performance. Through practice and learning, we can master the skills of using DMA and maximize its effectiveness in scenarios such as high-speed data transmission and real-time signal processing.

C code optimization can be achieved through the following strategies: 1. Manually manage memory for optimization use; 2. Write code that complies with compiler optimization rules; 3. Select appropriate algorithms and data structures; 4. Use inline functions to reduce call overhead; 5. Apply template metaprogramming to optimize at compile time; 6. Avoid unnecessary copying, use moving semantics and reference parameters; 7. Use const correctly to help compiler optimization; 8. Select appropriate data structures, such as std::vector.

To safely and thoroughly uninstall MySQL and clean all residual files, follow the following steps: 1. Stop MySQL service; 2. Uninstall MySQL packages; 3. Clean configuration files and data directories; 4. Verify that the uninstallation is thorough.

MySQL functions can be used for data processing and calculation. 1. Basic usage includes string processing, date calculation and mathematical operations. 2. Advanced usage involves combining multiple functions to implement complex operations. 3. Performance optimization requires avoiding the use of functions in the WHERE clause and using GROUPBY and temporary tables.

C performs well in real-time operating system (RTOS) programming, providing efficient execution efficiency and precise time management. 1) C Meet the needs of RTOS through direct operation of hardware resources and efficient memory management. 2) Using object-oriented features, C can design a flexible task scheduling system. 3) C supports efficient interrupt processing, but dynamic memory allocation and exception processing must be avoided to ensure real-time. 4) Template programming and inline functions help in performance optimization. 5) In practical applications, C can be used to implement an efficient logging system.
