JPEG2000 Stand alone DVR User Guide

CHAP.7 Network and client software

7-1 Network Introduction

Users have to indentify what kind of Internet access they have before they set up the DVR’s network parameters. DSL and cable modem are the most popular broadband technologies.

ADSL- Asymmetric Digital Subscriber Line

ADSL is one of xDSL technologies, transmitting digital data over the wires of a local telephone network. Typically, the download speed of DSL ranges from 128 kilobits per second (kbit/s) to 24,000 kbit/s depending on DSL technology and service level implemented. Upload speed is lower than download speed. ADSL is the most popular broadband technology, followed by Cable Modem.

Cable Modem(or Cable)

Cable Modem, Cable Internet Acess, or simply Cable is to deliver the Internet Service over a coaxial cable line, which can be the cable of your Cable TV. The bandwidth of Cable ranges from 3 Mb to 15 Mb, or more. The upload bandwidth usually ranges from 384kb to 2Mb, or more. However, the connection speed may drop when many people are using the sevice at the same time

7-2 Network installation and setup

7-2-1 Via Cable

Connect the Network cable of Cable Modem output to DVR

Enter [SYSTEM MENU]f [EXTERNAL DEVICE] f [TP/IP SETUP]f[DHCP SETUP]f[DHCP MODE]. Place the cursor at DHCP MODE and press ENTER to switch the DHCP MODE to [AUTOMATIC]. Then, move the cursor over [DETECT IP] and press ENTER to detect IP. DVR will automatically get the IP ADDRESS, SUBNET MASK, and GATEWAY from the Cable Modem and shows the IP information on the DVR.

Press MENU and go back to the previous setup page, [TP/IP SETUP]. Go to [IP CONFIG SETUP] to set up the port number. You can either use the default port number or assign a new one.

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Hitachi JPEG2000 manual CHAP.7 Network and client software, Network Introduction, Network installation and setup, Via Cable

JPEG2000 specifications

Hitachi JPEG2000 is a high-performance image compression technology that utilizes advanced coding techniques to provide superior image quality while maintaining a smaller file size. It is built upon the JPEG2000 standard, which was developed by the Joint Photographic Experts Group (JPEG) to address limitations in traditional JPEG compression methods, particularly in terms of scalability, quality, and error resilience.

One of the main features of Hitachi JPEG2000 is its use of wavelet compression. Unlike the Discrete Cosine Transform (DCT) employed in standard JPEG, which works on small blocks of images, JPEG2000 utilizes a wavelet transform that allows for multi-resolution analysis of images. This means that images can be compressed at various quality levels, enabling users to access lower-resolution versions without needing to decompress the entire image. This scalability is particularly beneficial for applications like streaming and remote visualization, where bandwidth may be limited.

Another significant characteristic is its superior error resilience. Hitachi JPEG2000 is designed to gracefully handle data corruption that can occur during transmission. This feature is crucial for applications in medical imaging or satellite imagery, where maintaining image integrity is essential. The technology allows for random access to image components, enabling portions of an image to be retrieved without needing to decode the entire file. This capability enhances efficiency when dealing with large datasets.

Additionally, Hitachi JPEG2000 supports lossless compression, meaning that the original image quality can be preserved without any loss of data during compression. This is particularly important for fields such as healthcare, where diagnostic imaging requires absolute precision. The algorithm also offers adjustable compression rates, providing flexibility for different use cases without compromising quality.

The technology is widely implemented in various industries, including broadcasting, film production, and medical imaging, thanks to its ability to deliver high-quality images in a manageable file size. As a versatile solution, Hitachi JPEG2000 stands out with its combination of advanced compression techniques, error resilience, and scalability, making it a preferred choice in an increasingly digital world where efficient data handling is paramount.