Proceedings of the Meeting & workshop on Development of a National IT Strategy Focusing on Indigenous Content Development

Transcription

1 Ministry of Science, Research & Technology Iranian Information & Documentation Center (Research Center) Proceedings of the Meeting & workshop on Development of a National IT Strategy Focusing on Indigenous Content Development Iran-Tehran October, 2 nd & 3 rd Octobr,2004

2 7 Digital Archive Management System of Audio and Video Resources Technical planning and development deportment IRIB organization Abstract Efforts are currently underway in many countries to design and convert libraries and archives into a digital form as a mean to maintain and conserve old media and documents. It also offer new ways of accessing digital content. This paper is a proposal for a system with which to develop highly reliable audiovisual archive network amenable to a different set of information services. Audio and video storage formats, data storage media, archive work cycle and infrastructure network are the most important factors for designing a digital archive system. Keywords: Archive; digital; resource management; media; audio and video 1.Introduction Given the Activities and processes within an organization, a huge number of documents and resources need to be managed with a ideal tool for archiving; especially so when an organization has been around for a long time. This is a significant issue especially for media agencies such as news agencies and broadcasting organizations to whose role in the society has been important to governmental managers. Currently, initiatives are underway in many countries around the world for design of digital libraries and the coversion of the existing ones as a mean to preserve the aging collection as well as offering new ways of accessing the content. CNN archive is one such example. CNN is converting about 100,000 hours of audiovisual content to digital and integrate new media with its working daily production system. The project uses high-end professional products from IBM and SONY high professional products to achieve desirable goals. Another example is a project to build a Digital Music Library in National Science Foundation of USA. The offer of this project is made from Indiana University. This paper will present the outline of an audiovisual archive network with high reliability and different information services.

3 76 / Documents of a Meeting & Workshop 2. Overall architecture of digital archive Architecture design of the project is based on a distributed model. Characteristics of such a system are as follows: all archival information is stored in a section named central archive. The main task of this section is preservation of the main documents in a secure way, with limited access. The next part is consisted of the archives integrated with production departments. In this section, a user can access archival content and produce desired programs by applying changes and editing digital content. Access rates to information here is certainly higher than the central archive and as a result there is vital need for higher bit rate access. The issues of both kinds of archives will be discussed separately later. Digital archive is capable of converting audiovisual material to its digital format so that the genuine copy of the content will be well preserved. In this conversion process, two separate digital copies of the resource will be made. One is with high quality for long term archiving and the other has a lower quality for applications like as search, browse and editing. The Information Management System (IMS) of the system is consisted of a search engine by which user can search for or browse a topic in a set of information in the central database. The user interface of the search engine gives the possibility to access the main database, interactive search and loading information. Fig 1: Schematic diagram of overall archive system architecture This search engine utilizes access and network options offered by Oracle database engine and offers these features: 1. Real-time browse of audiovisual clips and related information 2. Real-time connection to a broad range of server systems through Oracle database engine 3. Information exchange between main database and cache or editing systems Another section shown in figure 2-1 is a clip player. This system can play MPEG2 or MPEG1 files from hard drive, network or a DLT drive. The central part of the main database server is a high quality digital encoding system. In this section it is possible to encode input video to MPEG format with archive quality. Also, in this system copying data and transferring them to CD or

4 Digital Archive / 77 DVD and controlling CD or DVD writer is possible to achieve best copying operation needs. Figure 2-2 shows facilities of this system. Fig 2: Central database server facilities As already mentioned the system is divided to three parts: storage formats, storage media and archive network which will be discussed in the following sections Storage Formats of audio and video content In the Information Resource Center (IRS) of the system, audio and video archives are designed to be separate, but in the resource management system they are integrated to help the process of management achieved faster. The encoding formats of Audio are as follows: PCM (48, 44.1, 24, 22.1) KHz, {24, 16} Bit MPEG II L3 128 Kbit MPEG II AAC 128 Kbit In the video resource conversion section, desired format for archive quality is MPEG II 50 Mbps but the users would access content is browse quality which for this purpose MPEG II 7-15 Mbps is chosen. 2-2 Storage Media Several parameters influence the choice of data storage media like as media life time, resistance against damage, data transaction rate, data access time, data recovering features, Cost/MB ratio, peripheral equipment cost and data rewriting feature on media. So the recommended media depends on the target organization policy on the mentioned parameters above. Data access modes in digital media are categorized in three groups:

5 78 / Documents of a Meeting & Workshop 1. Off-line mode: In this mode the storage media is put in appropriate media normally. (CD, Diskette) 2. Near-line mode: Data will be recovered automatically if needed. (Tape library) 3. On-line Mode: Data is available at any time. (RAM, Hard Disk) Storage media are classed in four groups: tape, disk, optical and memory. We would not talk about memory because it is prohibitively expensive and we continue with other three items. Figure 2-3 shows a brief comparison of the four types of media. Fig 3: Comparison of different types of media It is obvious that as we go up through the memory pyramid, the capacity will decrease but cost and performance increase. We need to store about 1 terabyte of audio and 1 terabyte of video data in order to store1000 hour music and 40 hours video as needed. After working on world market we chose DLT system for audio/video storage. DLT systems have low Cost/Storage rate and long life time. In production archive, it is better to use optical media like DVD for storage and I/O activities, because the processing time of such a system is low. However, because of huge volume of data in video, we will use DLT tape for video storage in both central and production archives. Finally the best option for media storage is here: 1. Central Archive Video Storage : DLT o (NAS DLT 800 series, HP product with capacity of 800 GB to 1.6 TB) Audio Storage:DLT o (NAS DLT 800 series, HP product with capacity of 800 GB to 1.6 TB) 2.Production Archive Video Storage : DLT o (NAS DLT 800 series, HP product with capacity of 800 GB to 1.6 TB) Audio Storage: DVD-R

6 Digital Archive / Digital Archive Network A two layer model is used to design the archive network, because the users are categorized in different groups. One layer contains system clients while in the other servers and storage media are working. The system is designed in a way that the applied storage media can fulfill desired access and data acquisition rates and is independent from network backbone of an organization. The technology used to design the network is SAN. This technology is mostly new to the market and its strategy for offering a high quality of service is based on keeping storage resources separate from servers while the connection is made through a high speed fiber channel network. These networks give the servers opportunity to access storage media with a high bandwidth (from 100 to 400 MB/S). The backbone of storage network in SAN can be either of Arbitrated type and loop or switching one. But a direct access to media in such network is prohibited. Fig.4. Digital archive audio and video network The idea for separating storage and servers in SAN technology is shown in figure Processes, Services and data in archive data management Archive centers work with following processes and services in addition to information production: Information production; which is done according to review form, and is a process. Review; which done by archive centers and results the review form. Receipt export; for the producer and is done after review process and considered as form production. Registration; is an initial process and is used until archive material is prepared. Search, is done by the user of archival material or archivist and can be in production department or all archive centers.

7 80 / Documents of a Meeting & Workshop Borrow; is done by archive centers and containing registration in the member file. Archival material records; which has the name of the borrower and date field and also the state of the material when returned to archive. Review after return from borrow; to confirm its condition and as a result recording in member profile and archival material related file. Membership; making a new file and taking new members. Listing; which is fulfilled by information production department or directly by archive centers themselves. Exporting reports; like as periodical reports of archive activities. The figure 2-5 shows the existent state of information production of an archive material, in other words the life cycle of an archival material. The figure 2-6 is a proposed algorithm for automation of the mentioned life cycle. As is shown in the figure, the automation process of a system is well been companied by old hand operation extraction, to delete extra processes and optimization of all aspects of archiving process. It is necessary to mention that this diagram is an initial and overall algorithm and more details of the processes can be achieved through more studies. Archival material receipt R Sending to information Receipt export for producer Listing page production by information production Record in archive offices Preparing Saving in information production Sending to related archive Saving in archive storage Saving Borrow Profile production for borrower and archival t i l Fig 2: life cycle of information

8 Digital Archive / Conclusion This system is more efficient in comparison to similar systems because of using SAN high technology Network and also a Fiber channel backbone in storage networking. As a result a high speed data transaction rates. Another facility which gave the overall system the power of easy to use applications is to choose two types of audio and video formats for browsing and archiving. At last there is a proposed algorithm for optimization of the life cycle of archival material which brings the system a flexible operation to be changed according to customer needs.