3 DRI and Digital File audio and audio visual. AV files are created using complex processes t Format Choices of compression and encoding File format choices are an known as codecs and then placed in extremely important component wrappers or containers. Containers e of any digital preservation strategy. must be in readable formats but it As technology develops, digital is the codec that determines the formats can change quickly and quality of the file. The container old formats become unreadable. name determines the file Long-term support for proprietary extension but does not necessarily formats may not be guaranteed as determine the codec. DRI therefore companies cease trading or simply recommends that codec file formats stop supporting older versions of a are checked before ingestion to the particular format. For this reason, repository. DRI’s strategy is to recommend formats that are as sustainable as File Formats in DRI possible in the long term. The DRI policy for ingestion of file formats will be reviewed regularly File Format to reflect changes in technology and Identification data collections. In order to guarantee continued Preferred formats are act she access to data over the long recommended archival formats, f term, it is important to first best suited for long-term digital identify file formats. File format preservation; acceptable formats DRI Factsheet Series No. 3: File is not necessarily indicated by file are commonly used, but not ideal Formats. (Version 3, November extension. While extensions are used for long-term digital archiving. 2018) by the operating system to associate They are often lower quality or file types with specific programs, proprietary. If you have a choice, please contact: they are not enforced. For example we recommend capturing in a .txt file can easily be renamed as a preferred formats. .doc file without making any changes The Digital Repository to the file itself. It is important Generally DRI does not recommend of Ireland therefore, to identify file formats to converting files from an acceptable Royal Irish Academy ensure long term accessibility and to a preferred format [for instance, 19 Dawson St, preservation. from MP3 to WAV, or JPEG to TIFF], Dublin 2 as this will not improve quality, and There are certain types of data that may in fact reduce it. In some cases www.dri.ie pose a particular challenge in terms however, this may be unavoidable. [email protected] of file format identification, for In these cases it is recommended to @dri_ireland example time based media such as keep the original as well. 1 3 DRI PREFERRED AND ACCEPTABLE FORMATS (March 2018) t Audio (Preferred): FLAC, WAV, BWAV Audio (Acceptable): MP3, MP2, AIFF e Image (Preferred): TIFF (lossless), PNG Image (Acceptable): JPEG, JPEG2000 Text (Preferred): PDF/A, txt, XML, plain text Text (Acceptable): PDF, DOC, DOCx Note: these are the formats DRI currently recommends, and the range of ingestible formats will continue to grow over time. The most recent version of this factsheet will always be published on our website. Please check www.dri.ie/publications for the most up to date version. act she f Audio Visual formats will help to ensure that the data is accessible in its original capture The long term preservation of digital AV quality, through changes in software. is complicated by the nature of the file formats in question. More so than other The Library of Congress in the United digital formats, preservation of digital States provides tables of format AV content is affected by factors such descriptions for a variety of digital as the proprietary nature of certain audio-visual formats, including formats, the workflow environment sustainability factors. The list for required to render these formats, as moving image can be found here: well as issues relating to obsolescence https://www.loc.gov/preservation/ and ongoing software and hardware digital/formats/fdd/video_fdd.shtml support. AV is often produced using proprietary commercial products. Nestor, a network of expertise in The files, therefore, are dependent long-term storage of digital resources on a particular product environment in Germany makes recommendations with its own editing, format-shifting for the conversion of analogue film and playback software in order to be formats, analogue tape formats rendered visible. If an organisation and digital tape formats into digital decides that it can no longer pay for formats. Recommendations for suitable these products, or if the vendor decides digital image, container and codec to cease support for certain versions of formats can be found at Leitfaden its products, it can be very difficult to für die digitale Langzeitarchivierung operate the files in a manner which is audiovisueller Medien. (2016). both legal and reliable. [ebook] Germany: nestor, network of expertise in long-term storage Think about sustainability: of digital resources, pp.116-119. Available at: http://nbn-resolving.de/ The ideal formats for digital urn:nbn:de:0008-2016102107 . preservation are lossless, open-source, and widely supported. Using such 2 Creating a policy: Preferred Archival Format: It is recommended to develop an Matroska (*.mkv) is a suitable archive 3 Institutional Policyto guide the format. It is open, robust, of little preservation of audio visual collections. complexity, non-proprietary, widely A number of different factors will affect used container format that has a t the choices an archive or organisation relatively small file size. The conversion makes - the nature of the recorded to Matroska is uncomplicated with e content they encounter, the software conventional conversion software and hardware at their disposal, the in- (e.g. Wondershare, XMedia Recode, house expertise, as well as competing FFmpeg). Equally as important as interests with preservation such as the the container format is the video need for short term access and editing compression format (codec). The of files. Development of an institutional lossless, open source codec FFV1 is policy will inform an archive’s decisions suitable for long-term preservation. regarding the best workflow and While there is no complete consensus formats for their needs. among the archival community as to which file format or codecs should be When dealing with digital AV, there are used for preservation purposes for act she two broad categories: analog material digital video, FFV1 has seen increasing f that has been digitised, and born- support and interest amongst many digital files. In order to determine the professional archives as a long-term best preservation strategy for your storage codec. AV content you must first identify the significant properties of the current For a comprehensive list of video format. Significant properties such formats and their suitability for as frame rate, colour space and preservation please see the Guidelines resolution conform to specific playback for the Preservation of Video environments like digital cinema, Recordings IASA-TC 06 published by television broadcast, web streaming or the International Association of Sound playback in a computer environment. and Audio Visual Archives: https:// www.iasa-web.org/tc06/guidelines- Tools such as MediaInfo, a free and preservation-video-recordings open-source program that displays technical information about media All links accessible as of July 2018. files, allow for the identification of such properties and help you to understand the playback environment of your AV content. Good knowledge management of this inherently transitional medium is key to ensure authentic playback in an often very near future. A list of useful open-source tools can be found here: Leitfaden für die digitale Langzeitarchivierung audiovisueller Medien. (2016). [ebook] Germany: nestor, network of expertise in long-term storage of digital resources, pp.114. Available at: http://nbn-resolving.de/ urn:nbn:de:0008-2016102107. 3.