HTTP Headers Pro vs HCC2D Decoder

HTTP是一个客户端终端（用户）和服务器端（网站）请求和应答的标准（TCP）。通过使用Web浏览器、网络爬虫或者其它的工具，客户端发起一个HTTP请求到服务器上指定端口（默认端口为80）。我们称这个客户端为用户代理程序（user agent）。应答的服务器上存储着一些资源，比如HTML文件和图像。我们称这个应答服务器为源服务器（origin server）。在用户代理和源服务器中间可能存在多个“中间层”，比如代理服务器、网关或者隧道（tunnel）。 尽管TCP/IP协议是互联网上最流行的应用，HTTP协议中，并没有规定必须使用它或它支持的层。事实上，HTTP可以在任何互联网协议上，或其他网络上实现。HTTP假定其下层协议提供可靠的传输。因此，任何能够提供这种保证的协议都可以被其使用。因此也就是其在TCP/IP协议族使用TCP作为其传输层。 通常，由HTTP客户端发起一个请求，创建一个到服务器指定端口（默认是80端口）的TCP连接。HTTP服务器则在那个端口监听客户端的请求。一旦收到请求，服务器会向客户端返回一个状态，比如"HTTP/1.1 200 OK"，以及返回的内容，如请求的文件、错误消息、或者其它信息。 所有HTTP响应的第一行都是状态行，依次是当前HTTP版本号，3位数字组成的状态代码，以及描述状态的短语，彼此由空格分隔。 状态代码的第一个数字代表当前响应的类型： 1xx消息——请求已被服务器接收，继续处理 2xx成功——请求已成功被服务器接收、理解、并接受 3xx重定向——需要后续操作才能完成这一请求 4xx请求错误——请求含有词法错误或者无法被执行 5xx服务器错误——服务器在处理某个正确请求时发生错误

This app allows you to scan and decode HCC2D and QR code symbols using your mobile camera. It is based on advanced research in high-capacity barcode technologies and provides reliable decoding. Key features: * Decode HCC2D color codes. * Full support for standard QR codes. * Real-time scanning using the camera. * Robust detection and error correction. * No ads and no registration required. HCC2D is a color two-dimensional code format that increases data capacity compared to traditional QR codes while preserving their structure. By using multiple colors, each module can encode more information, enabling higher data density in a compact symbol. The app captures images, detects barcode regions, corrects perspective distortions, and analyzes color or intensity patterns to reconstruct the encoded data. To transfer files from a desktop computer to your smartphone via a stream of HCC2D codes, use HCC2D Decoder together with the HCC2D Streamer desktop companion app. Notes: HCC2D codes can be created using the official online generator at hcc2d.com, the HCC2D Encoder application, the open-source CLI encoder, or the Debian/Ubuntu packages provided through the official HCC2D APT repository. * Low-quality color printing may reduce decoding performance * Best results are achieved with screen-displayed or high-quality printed codes and a high-resolution autofocus camera. * One-dimensional barcodes are intentionally not supported. References: * Querini, M. (2026). HCC2D Code Specification — Version 0.9.0. Zenodo. https://doi.org/10.5281/zenodo.22206528. Licensed under the Creative Commons Attribution-NoDerivatives 4.0 International License (CC BY-ND 4.0). * Querini, M. and Italiano, G. F. (2014). Reliability and Data Density in High Capacity Color Barcodes. Computer Science and Information Systems, 11(4), 1595-1615. * Querini, M., Grillo, A., Lentini, A., and Italiano, G. F. (2011). 2D Color Barcodes for Mobile Phones. IJCSA, 8(1), 136-155. * Querini, M. (2010). Analysis and Design of High-Capacity Two-Dimensional Codes. Development of the Reader for Desktop and Mobile Environments (Bilingual Digital Edition 2026, Version 1.0). Zenodo. https://doi.org/10.5281/zenodo.22206722 Notice: This application is an independent personal project and is not affiliated with any organization or institution.