ARTICLE

DEVELOPING AN MXF AUDIOVISUAL PRESERVATION FILE WRAPPER SPECIFICATION IN THE FEDERAL AGENCIES DIGITIZATION GUIDELINES INITIATIVE Carl Fleischhauer, Library of Congress, USA 8LMW TETIV MW FEWIH SR E TVIWIRXEXMSR QEHI EX XLI -%7%%1-%  NSMRX GSRJIVIRGI MR Philadelphia, November 4, 2010.

Introduction 8LMWTETIVHIWGVMFIWETVSNIGXXSHIZIPSTE½PI[VETTIVWTIGM½GEXMSRJSVXLIEVGLMZMRKERH TVIWIVZEXMSRSJEYHMSZMWYEPGSRXIRX8LIWTIGM½GEXMSRYRHIVHIZIPSTQIRXMWERMQTPIQIRXE- XMSRSJXLI1EXIVMEPIuncompressed video streams, and many more, as well as soundtracks, time- code, closed captioning, metadata, and more. This wrapper function may be compared to XLI8-**ERH;%:)½PIJSVQEXWFSXLSJ[LMGLQE]GSRXEMRERYQFIVSJHMJJIVIRXVITVI- WIRXEXMSRWSJVEWXIVMQEKIHEXE 8-** SVWSYRH[EZIJSVQHEXE ;%:) 8LIZMVXYIWSJ 1<*MRGPYHIWXERHEVHM^EXMSRF]7148)EVSFYWXWXVYGXYVIJSVXLIGSRXEMRQIRXSJZEVMSYW related essences, and a clear mission to support professionally produced moving image GSRXIRX-XMWEPWSXLIGEWIXLEXXLIJSVQEXMWGSQTPI\ERHXLEXMXWEHSTXMSR[MXLMRXLI industry has been slow, albeit steady. 8LI*IHIVEP%KIRGMIW(MKMXM^EXMSR+YMHIPMRIW-RMXMEXMZI[EWPEYRGLIHMRYRHIVXLIEYW- TMGIWSJXLI2EXMSREP(MKMXEP-RJSVQEXMSR-RJVEWXVYGXYVIERH4VIWIVZEXMSR4VSKVEQ 2(--44  at the Library of Congress. The overall initiative is a collaborative effort with participation JVSQQSVIXLERSRIHS^IR97KSZIVRQIRXEKIRGMIWMRGPYHMRKXLI2EXMSREP%VGLMZIWERH 6IGSVHW%HQMRMWXVEXMSRXLI2EXMSREP+EPPIV]SJ%VXXLI:SMGISJ%QIVMGEXLI2EXMSREP0MFVEV] SJ1IHMGMRIXLI7QMXLWSRMER-RWXMXYXMSRERHWIZIVEPSXLIVW-XEPWSLEWEGXMZITEVXMGMTEXMSR JVSQXLI0MFVEV]SJ'SRKVIWW%YHMS:MWYEP'SRWIVZEXMSR'IRXIVEXXLI4EGOEVH'EQTYWMR 'YPTITIV:MVKMRME

Current activities and planning 8LI;SVOMRK+VSYT[EWQSXMZEXIHXSHIZIPSTER1<*EVGLMZMRKERHTVIWIVZEXMSRMQTPIQIR- tation because several member agencies face a pressing need to reformat videotapes. These agencies have extensive holdings of obsolescent magnetic recordings and wish to transfer XLIQXSE½PIFEWIHJSVQEX%XXLMWXMQIXLVIIQIQFIVWSJXLI;SVOMRK+VSYTEVIHSMRK WSQIHMKMXEPVIJSVQEXXMRKSJZMHIS8LI]LEZITYVGLEWIH7%11%HIZMGIWETVSHYGXSJXLI Front Porch Digital company.7 The Library of Congress has done the most work thus far, while XLI972EXMSREP%VGLMZIWERH6IGSVHW%HQMRMWXVEXMSRERHXLI7QMXLWSRMER-RWXMXYXMSREVI starting to carry out projects of their own.

5 For more information see, the background paper here: http://www.digitizationguidelines.gov/guidelines/FADGI-AV_AppSpecProj_Bkgd_101007.pdf 6 he initiative's goal is to develop guidelines that are comparable from agency to agency, for the sake of uniformity and to make it easier for the vendors who provide equipment and services. The main emphasis is digitization, i.e., XLIGSRZIVWMSRSJEREPSKSVMKMREPWMRXSHMKMXEPJSVQ8LIVIEVIX[S[SVOMRKKVSYTW8LI½VWXMWGSRGIVRIH[MXLXLI still images that result from the scanning of books, photographs, manuscripts, maps, two-dimensional art works, and other documents. The second is concerned with audio-visual materials, i.e., sound and video recordings and QSXMSRTMGXYVI½PQ&SXLKVSYTWLEZIEWIGSRHEV]MRXIVIWXMRXLITVIWIVZEXMSRSJFSVRHMKMXEPGSRXIRX7IIhttp:// www.digitizationguidelines.gov/. 7 http://www.fpdigital.com/Solutions/Migrate/

 iasa journal no 37 – July 2011 7%11%HIZMGIWGERFIWIXYTJSVERYQFIVSJHMJJIVIRXSYXTYXJSVQEXW8LI0MFVEV]MWYW- MRK7%11%´WFIWXORS[RWIXYTMRE[SVO¾S[XLEXTVSHYGIWEWXVIEQSJZMHISJVEQIMQ- EKIWIEGLIRGSHIHMRPSWWPIWW.4)+8LMWTMGXYVIHEXEXSKIXLIV[MXLXLIWSYRHXVEGO and timecode, is wrapped in MXF. Files in this format serve as archival masters for preser- ZEXMSRMRXLIQSZMRKMQEKIGSPPIGXMSRWEXXLI4EGOEVH'EQTYW*MPIWM^IWJSVWXERHEVHHI½- RMXMSRZMHISVYRJVSQXSKMKEF]XIWTIVLSYVHITIRHMRKSRZEVMEFPIWPMOIFMXHITXL 8LI0MFVEV]TVIJIVWFMXHIITWEQTPMRKERHXLYWMWGVIEXMRK½PIWSJXLIPEVKIVWM^I %XXLIWEQIXMQISXLIVWMRXLI;SVOMRK+VSYT°RSXEFP]XLI972EXMSREP%VGLMZIW°EVI MRXIVIWXIHMRIWWIRGIWXLEXGSRWMWXSJYRGSQTVIWWIHZMHISWXVIEQW-RXLMWXLI]IGLSWTIGM½GE- tions in use at Stanford and Rutgers universities, as well as at the BBC.8*MPIWM^IWJSVWXERHEVH HI½RMXMSRZMHISVYRJVSQXSKMKEF]XIWTIVLSYV)EGLQIQFIVSJXLIYRGSQTVIWWIH XVMSLEWWIPIGXIHEHMJJIVIRX[VETTIV5YMGO8MQIEX7XERJSVH%:-EX6YXKIVWERH1<*EXXLI &&'8SWSQIHIKVIIXLIX[SYRMZIVWMXMIW´5YMGO8MQIERH%:-ETTVSEGLIWGERFIWIIREW provisional, i.e., as a practical thing to do now, while better ideas and technology mature. %PXLSYKLXLI;SVOMRK+VSYT´WGYVVIRXGSRGIVRMWJSGYWIHSRXLIVIJSVQEXXMRKSJSPHZMHI- otapes, we also wish to develop an implementation of MXF that is extensible in at least three [E]W*MVWXXLIVIMWEHIWMVIXSIQFVEGIXLISYXTYXSJ½PQWGERRMRKEGXMZMXMIW7IGSRHSRI EKIRG]LEWI\TVIWWIHMRXIVIWXMRYWMRKXLI1<*JSVQEXXS[VET±EYHMSSRP]²IWWIRGIWXLEXVI- WYPXJVSQXLIVIJSVQEXXMRKSJWSYRHVIGSVHMRKW%RHXLMVHMWXLIQEXXIVSJFSVRHMKMXEPZMHIS 6IKEVHMRK FSVR HMKMXEP ZMHISXLI;SVOMRK +VSYT LEW JVIUYIRXP] LIEVH JVSQ SVKERM^EXMSRW EFSYXXLIMVKVS[MRKGSPPIGXMSRW7SQISJXLIWIEVI±RSRQIQSV]²STIVEXMRKEKIRGMIWIK XLI 2EXMSREP 3GIERMG ERH%XQSWTLIVMG%HQMRMWXVEXMSR 23%%  [LIVI QEVMRI FMSPSKMWXW ERHSXLIVWGMIRXMWXWEVITVSHYGMRKI\XIRWMZIZMHISJSSXEKI%RSXLIVI\EQTPIMWXLI:SMGISJ %QIVMGE[LIVIXLIWXEJJ[MWLXSVIXEMRGYVVIRXFVSEHGEWXTVSHYGXMSRWJSVJYXYVIVITYVTSWMRK 1IER[LMPI½PIWJVSQEKIRGMIWPMOIXLIWIEVIHIWXMRIHJSVJYXYVILERHSJJXSXLI972EXMSREP %VGLMZIWSVXLI0MFVEV]SJ'SRKVIWWJSVTIVQERIRXGYWXSH] The native encodingsJSVWSQIFSVRHMKMXEP½PIWEVITVSQMWMRKJSVWYWXEMREFMPMX]JSVEXPIEWX a few years, before format obsolescence reaches the point where transcoding is necessary. )\EQTPIWMRGPYHI14)+ERH½PIJSVQ(:3XLIVFSVRHMKMXEP½PIWEVIMRJSVQEXWXLEXQE] not be equally sustainable and these will require transcoding in the near term. We would like our MXF implementation to be capable of wrapping born digital encodings. For the sustainable REXMZIIRGSHMRKWXLMWEGXMSR[SYPHWYTTSVXRIEVSVQIHMYQXIVQTVIWIVZEXMSR-XMW[SVXL noting that some agencies are required to retain even the less sustainable native encodings for many years; for example, copyright legal considerations may require that an item is kept “as WYFQMXXIH²%PPSJXLIWIJEGXSVWLEZIQEHIYWWIIOER1<*[VETTIVMQTPIQIRXEXMSRXLEXGER be extended to embrace born digital essences. &I]SRHEPPSJXLMWQIQFIVWSJXLI;SVOMRK+VSYTLEZIMHIRXM½IHSXLIVGSRXIRXIPIQIRXWXLEX [SYPHFI[IPPWIVZIHF]ERI\XIRWMFPIJSVQEXVERKMRKJVSQHMKMXEPGMRIQEXS½PQWXVMTW[MXL soundtracks. Some members also see the archiving and preservation wrapper as a useful way to encapsulate items that are associated with the main content element. Examples of associ- ated materials include such things as documents found in the original container along with the videotape, printed matter associated with a sound or moving image publication, transcriptions SJSVEPLMWXSV]VIGSVHMRKWERHHIXEMPIHQIXEHEXESJWTIGMEP±PSGEP²MRXIVIWX

 8LI6YXKIVWWTIGM½GEXMSR960MW http://rucore.libraries.rutgers.edu/collab/ref/dos_avwg_video_obj_standard.pdf. Information about Stanford's reformatting is here: http://lib.stanford.edu/stanford-media-preservation-lab/moving- image-digitization%[LMXITETIVGSRXEMRMRKEHIWGVMTXMSRSJXLI&&'ETTVSEGLMWEXXLMW960www.bbc. GSYOVHTYFW[LT[LTTHJ½PIW;,4THf.

 iasa journal no 37 – July 2011

%FSYX1<*ETTPMGEXMSRWTIGMßGEXMSRWERHXLI%HZERGIH1IHME;SVOàS[ Association (AMWA) 1<*MWWIIMRKMRGVIEWMRKEHSTXMSRMRFVSEHGEWXMRKERHMXMWGIRXVEPXSXLIHMKMXEPGMRIQEWTIGM½- GEXMSRHIZIPSTIHMR,SPP][SSHJSVXLIEXVMGEPHMWXVMFYXMSR8LIWIMRHYWXVMIWMRGPYHIXLIFMKGYW- tomers for whom tools are built, and their broad-based adoption of MXF makes the standard EXXVEGXMZIXSYW-XMWEPWSXLIGEWIXLEX7148)MWXLIQSWXMQTSVXERXWXERHEVHWSVKERM^EXMSRJSV professional broadcasters and movie-makers. MXF is a broad-spectrum standard that features many options for packaging, metadata embed- ding, and essence encoding. The successful implementation of an MXF approach for any given ETTPMGEXMSR[MPPFIIRLERGIHMJYWIVWHI½RIEWIXSJGSRWXVEMRXW;IPPHI½RIHGSRWXVEMRXWWYT- TSVXXLIHIZIPSTQIRXSJXSSPWXSZEPMHEXI½PIWERHIRGSYVEKIQYPXMTPIZIRHSVWXSTVSZMHIGSR- JSVQMRKIUYMTQIRX8LIWIEGXMSRW[MPPMRGVIEWIXLIHIKVIIXS[LMGLTVEGXMGIWEVIWXERHEVHM^IH and promote adoption. Those two outcomes will in turn increase interoperability, the feasibility of content exchange, and long-term, preservation-oriented data management. For users of the MXF standard, formal constraint statements are called ETTPMGEXMSRWTIGM½GEXMSRW. 8LIWIGERFIGSQTEVIHXS.4)+TVS½PIWSVXSXLITVS½PIWERHPIZIPWXLEXGLEVEGXIVM^I 14)+ZMHISGSRXIRXIKXLI14)+1EMR4VS½PI$1EMR0IZIP 14$10 0MOIXLITVS½PIW IEGL ETTPMGEXMSR WTIGM½GEXMSR MW XEMPSVIH XS E TEVXMGYPEV application. The incubation of MXF %TTPMGEXMSR7TIGM½GEXMSRWMWXLIWTIGMEPTVSZMRGISJXLI%HZERGIH1IHME;SVO¾S[%WWSGMEXMSR %1;% ERSVKERM^EXMSRXLEXTVSZMHIWEQIIXMRKKVSYRHJSVTVSJIWWMSREPQSZMRKMQEKIYWIVW ERHZIRHSVW8LI;SVOMRK+VSYTMW[SVOMRK[MXL%1;%MRXLIHIZIPSTQIRXSJXLIETTPMGE- XMSRWTIGM½GEXMSR 3RISJXLIZMVXYIWSJ[SVOMRK[MXL%1;%MWXLIMRGPYWMSRSJFSXLYWIVWERHZIRHSVWMRXLI HMWGYWWMSR8LI%1;%[MPPJSVQEWTIGMEPXIGLRMGEPGSQQMXXIIXS½REPM^IXLIWTIGM½GEXMSRERH we anticipate that the committee’s membership will include archivists from memory institu- XMSRWEVGLMZMWXWJVSQFVSEHGEWXERHQSXMSRTMGXYVITVSHYGXMSRSVKERM^EXMSRWERHVITVIWIRXE- tives of the companies that manufacture the technology used by broadcasters and archives. We believe that this mix of participants will increase the likelihood that multiple vendors will FYMPHW]WXIQWXLEXQIIXXLIWTIGM½GEXMSR[LMGLMRXYVR[MPPMRGVIEWIXLIPMOIPMLSSHXLEXXVYP] interoperable content will be archived for the future.

;LEXQMKLX]SYßRHMRER%TTPMGEXMSR7TIGMßGEXMSR# %XELMKLPIZIPERETTPMGEXMSRWTIGM½GEXMSR[MPPGSZIVXLIJSPPS[MRK

„ %WTIGXWSJXLIYRHIVP]MRK1<*WXVYGXYVIIK[LMGLoperational patterns are permitted, the use of partitioning, and the handling of embedded metadata, the use of clip wrapping and/or frame wrapping „ 4MGXYVI°XLITIVQMXXIHIWWIRGIWGLIQIW IRGSHMRKW ERHSXLIVIPIQIRXW „ Sound — the permitted essence schemes and other elements „ The handling of timecodes „ 'PSWIH'ETXMSRWERHSXLIV:&-°EFSYXXLIIPIQIRXWMRXLI:IVXMGEP&PEROMRK-RXIVZEP of the source signal and how they are to be retained in the digital copy „ %WWSGMEXIHGSRXIRXIPIQIRXW°EFSYXXLIETTVSEGLXSFIYWIHXS[VETMREWWSGMEXIH items like still images, documents, and texts „ -RGPYWMSRSJ½PIMRXIKVMX]hash data ±GLIGOWYQW² XSFIYWIH[LIRQSRMXSVMRKHMKMXEP content over time.

9 http://www.amwa.tv/

37 iasa journal no 37 – July 2011 8LITEKIETTPMGEXMSRWTIGM½GEXMSR%7TYFPMWLIHF]XLI%1;%MRTVSZMHIWEKSSH sense of the structure and level of detail in this type of document.10%7MW±EZIRHSVRIYXVEP WYFWIXSJXLI1<*½PIJSVQEXXSYWIJSVHIPMZIV]SJ½RMWLIHTVSKVEQQMRKJVSQTVSKVEQTVS- HYGIVWERHTVSKVEQHMWXVMFYXSVWXSFVSEHGEWXWXEXMSRW²

%FSYX.4)+ERHSYVTVSTSWIHWTIGMßGEXMSR .4)+PMOI1<*MWEFVSEHWTIGXVYQWXERHEVH[MXLQER]STXMSRW-X[EWHIZIPSTIHF]XLI -RXIVREXMSREP7XERHEVHW3VKERM^EXMSR -73 ERHXLI-RXIVREXMSREP)PIGXVSXIGLRMGEP'SQQMWWMSR -)' ERHXLIJEQMP]SJWXERHEVHWHSGYQIRXWGEVVMIWXLIKIRIVEPMHIRXM½IV-73-)'11%X PEWXGSYRXX[IPZITEVXWLEZIFIIRTYFPMWLIH8LI.4)+GSQTVIWWMSRETTVSEGLIQTPS]W [LEXMWGEPPIHXLI[EZIPIXXVERWJSVQ;LIRYWMRK.4)+SRIRSXEFPISTXMSRMW[LIXLIV this transform is applied in an irreversible manner — resulting in lossy compression — or in a reversible manner — producing lossless compression. For our preservation-oriented applica- XMSRXLIQSWXHIWMVEFPI.4)+TVS½PIWEVIXLSWIXLEXJIEXYVIXLIVIZIVWMFPIXVERWJSVQ :EVMSYWQIQFIVWSJXLIQSZMRKMQEKIGSQQYRMX]LEZIFIIRHIZIPSTMRKHMKMXEPGMRIQE ERHFVSEHGEWXTVS½PIWJSV.4)+8LIQSWXVIGIRXTYFPMGEXMSRMWEQIRHQIRXXS TEVXSRISJXLI-73-)'WXERHEVHXMXPIH4VS½PIWJSV&VSEHGEWX%TTPMGEXMSRW -73-)' %QH 8[SSJXLIWIZIRTVS½PIWMREQIRHQIRXJIEXYVIXLIVIZIVW- ible wavelet transform, i.e., lossless compression. We plan to reference this standard in our 1<*ETTPMGEXMSRWTIGM½GEXMSR -RXLIGSYVWISJSYVI\TPSVEXMSRSJXLIMRXIVWIGXMSRSJ.4)+ERH1<*WTIGM½GEXMSRW[I have encountered one technical matter that is not fully resolved by the various existing docu- QIRXWXLILERHPMRKERHPEFIPMRKSJMRXIVPEGIHZMHIS)\TIVXWMRXLI½IPHLEZIWEMHXLEXXLIVI EVIERYQFIVSJHMJJIVIRX[E]WXSIRGSHIERHPEFIPMRXIVPEGIHTMGXYVIHEXEMRXLMWGSRXI\X%X a high level, there is the question of whether the image stream consists of a series of ½IPHW or frames%XE½RIVPIZIPXLIVIMWXLIQEXXIVSJLS[XSMRHMGEXI[LMGL½IPHMWHSQMRERXERHLS[ or when to employ what the MXF standard calls frame-wrapping as compared to clip-wrapping. -JHMJJIVIRXETTVSEGLIWEVIEHSTXIHF]HMJJIVIRXTVSHYGXMSRW]WXIQWERHMJXLIPEFIPMRKMWMREH- IUYEXIXLIVIMWEVMWOXLEX½PIW[MPPRSXMRXIVSTIVEXIMIXLEXE½PITVSHYGIHSRW]WXIQ%[MPP not play back on system B. ,S[WLSYPHMRXIVPEGIHMQEKIJVEQIWSV½IPHWFI[VETTIHERHPEFIPIH#;LEXFSH]WLSYPHHI- PMFIVEXIXLMWUYIWXMSR#3RIXIGLRMGEPI\TIVXMRXLI-73-)'.4)+WXERHEVHWGSQQYRMX] RSXIHXLEXXLMWMWWYIMWRSXWTIGM½GEPP]EFSYXTMGXYVIIRGSHMRK±-XLEWXSHS[MXLLS[]SYTYX XLIWXVIEQMRE½PI²LIWEMH±ERHXLEXQEOIWMXER1<*TVSFPIQ²EHHMRK±MX[MPPRSXFITEVXSJ SYV[SVOEW[IGSRXMRYIXSHIZIPSTFVSEHGEWXTVS½PIW²12 3YV;SVOMRK+VSYTEKVIIWERH[I[IVITPIEWIHXSPIEVRSJVIGIRX7148)TPERWXSWTIGMJ]ER ETTVSEGL SVETTVSEGLIW JSVMRXIVPEGIHTMGXYVIHEXEMREXSFIHVEJXIHEQIRHQIRXXS7148) 78Material Exchange Format - Mapping JPEG 2000 Codestreams into the MXF Generic Container.138LMWWXERHEVH[EWSVMKMREPP]HVEJXIHXSWYTTSVXXLIHMKMXEPGMRIQEWTIGM½GEXMSR Since digital cinema consists of progressively scanned images, ST 0422 does not include recom- mendations for the handling of interlaced picture data. For the time being, we plan to include SYVS[R[SVHMRKSRMRXIVPEGMRKMRWYGGIWWMZIHVEJXWSJSYV1<*ETTPMGEXMSRWTIGM½GEXMSRIZIR as we track the revision of SMPTE ST 0422.

10 LXXT[[[EQ[EXZHS[RPSEHWWTIGM½GEXMSRW%1;%%7(IPMZIV]7TIGCTHf 11 0MWXMRKWSJEPP-73WXERHEVHWQE]FIJSYRHLIVIhttp://www.iso.org/iso/iso_catalogue.htm. 12 Personal communication. 13 http://store.smpte.org/product-p/st%200422-2006.htm

38 iasa journal no 37 – July 2011

Ancillary data -XMW[SVXLRSXMRKXLEXXLIVIMWEWMQMPEV[EMXERHWIIWMXYEXMSRVIKEVHMRKGPSWIHGETXMSRMRKERH other ancillary data and, by extension, motion picture subtitles and other forms of adjunct content. On the video side, there are number of engineering nuances but roughly speaking this MWEFSYXXLIHEXEJSYRHMREREPSKZMHISWMKREPWMRXLIZIVXMGEPFPEROMRKMRXIVZEP :&- ERHEFSYX XLIWMQMPEVHEXEMRXLIHMKMXEPVIEPQVIJIVVIHXSEW:%2'8LIVIMWEPWSLSVM^SRXEPERGMPPEV]HEXE SV,%2'7SQISJXLMWTIVXEMRWXS2SVXL%QIVMGERWXERHEVHW XLIVIEVIEPWSQYPXMTPIIQFIH- HIHHEXEWTIGM½GEXMSRWMRTPE]MRSXLIVTEVXWSJXLI[SVPHMRGPYHMRKXLI)YVSTIER&VSEHGEWX 9RMSR´W7YFXMXPMRK(EXE)\GLERKI*SVQEX )&9780 

Why worry about retaining this embedded data? We believe that it includes information that is RIIHIHXSTVSTIVP]YRHIVWXERHERHQEREKIZMHISGSRXIRXSFNIGXWJSVXLIPSRKXIVQ-RWSQI cases, the embedded data may be construed to be an essential part of the original item that QYWXFIQMKVEXIHJSV[EVHMRSVHIVXSGVIEXIEREYXLIRXMGERHGSQTPIXIGST]-RWSQIGEWIW XLIIQFIHHIHHEXEGSRXEMRWMRJSVQEXMSR GPSWIHGETXMSRWSVWYFXMXPIWSXLIVHIWGVMTXMZIMRJSV- QEXMSR XLEX°SRGIMRKIWXIHERHMRHI\IHMRXSEWIEVGLW]WXIQ°[MPPWYTTSVXVIWIEVGLIVW who seek to discover relevant materials. The embedded data is also likely to contain technical information that will support the management of the item and may also shed light on produc- tion-method or provenance topics of interest to researchers. 3YVI\TPSVEXMSRLEWLMKLPMKLXIHWSQISTXMSRWXSGSRWMHIV[LMGL-[MPPHIWGVMFIMRWMQTPM½IH JSVQ8LI½VWXSTXMSRIQFVEGIWcurrent practices and trades on the use of what are called ANC packets in SMPTE standards.14 The second option pertains to an emerging practice that should accommodate both US and European formats. This option would employ the structures being WXERHEVHM^IHMR7148)888MQIH8I\XWXERHEVHW XLI78JEQMP] FIMRKTYFPMWLIHHYVMRK 2010 and 2011.1IER[LMPIXLIVIMWE)YVSTIER&VSEHGEWX9RMSRTVSNIGXXSWXERHEVHM^IXLI GEVVMEKISJ)&9780MRWMHI1<*½PIW*MREPP]XLIVIMWEGYVVIRXTVEGXMGIEQSRKFVSEHGEWXIVW XSGVIEXIWMHIGEV½PIW WITEVEXIHEXE½PIWRSXIQFIHHIHMRXLIQEMR1<*½PI XLEXGSRXEMR :&-ERHVIPEXIHHEXE8LMWQE]FITVEGXMGEPJSVXLIRIEVXIVQFYX[I[SYPHTVIJIVXSWIIXLI EHSTXMSRSJEWXERHEVHM^IHIQFIHHIHHEXEETTVSEGL

Metadata Our federal agencies discussions thus far have highlighted a dual approach to the embed- HMRKSJQIXEHEXEMR1<*EVGLMZMRKERHTVIWIVZEXMSR½PIW3RXLISRILERH[ILEZIXEPOIH EFSYXEQMRMQEPLIEHIV SVLIEHIVPMOI IPIQIRX-RWTMVMXXLMW[SYPHFIEOMRXSXLI&VSEHGEWX )\XIRWMSR FI\X GLYROMRXLI&VSEHGEWX;%:)½PIWXERHEVHM^IHF]XLI)YVSTIER&VSEHGEWX 9RMSR-RTVEGXMGI[I[SYPHPMOIXSWIIWSQIXLMRKPIWWGSRWXVEMRIH[MXLVSSQJSVEFMXQSVI HEXERSXXLIPIEWXSJ[LMGL[SYPHFIQYPXMTPIXEKKIHMHIRXM½IVW8LIHEXEMRXLILIEHIVPMOI element would be basic, consisting of metadata needed to identify and manage the content object as an object, e.g., in a preservation storage system. On the other hand, to support more complete representations of descriptive, administrative, ERHXIGLRMGEPQIXEHEXE[IEVIHMWGYWWMRK½RHMRKTPEGIW±HIITIVMRXLI½PI²3PMZIV1SVKERXLI ;SVOMRK+VSYT´WI\TIVXGSRWYPXERXLEWGEPPIHSYVEXXIRXMSRXS[LEXEVIGEPPIHKeneric stream partitions8LIWIIPIQIRXW[MXLMR1<*EVIWXERHEVHM^IHMR7148)78XMXPIHMaterial Exchange Format - Generic Stream Partition. These partitions were established for a variety of

14 )RKMRIIVMRK[SVHMRKJSVXLI½VWXSTXMSRQE]FIJSYRHMRXLI7IGXMSRSJ%7STGMX-JTVIWIRX')% line 21 (CC and XDS) data shall be carried in a SMPTE ST 334-1:2007-and-ST 334-2:2007-compliant ANC packet within a SMPTE ST 436:2006-compliant VBI/ANC GC Element, using 8 bit encoding. If present, CEA 708B DTV captioning data shall be carried in a SMPTE 334-1:2007-and-ST 334-2:2007-compliant ANC packet within E7148)78GSQTPMERX:&-%2'+')PIQIRXYWMRKFMXIRGSHMRK'ETXMSRPERKYEKIWLEPPFIWTIGM½IH YWMRK%1;%%7 15 The introductory standard is SMPTE 2052-0:2010: http://www.smpte.org/standards/st2052-0-2010.pdf

 iasa journal no 37 – July 2011 applications, one of which was to contain various classes of data streams, such as extensive FPSGOWSJ±QIXEHEXEXLEXGERRSXWYMXEFP]FIWXSVIHMRXLI,IEHIV1IXEHEXE IKWTIGMEPM^IH TVIWIVZEXMSRQIXEHEXE ²%GSVSPPEV]6IGSQQIRHIH4VEGXMGIHSGYQIRXJVSQ7148)MW64 XMXPIHText-Based Metadata Carriage in MXF[LMGL±HI½RIWLS[XSGEVV]XI\XFEWIH QIXEHEXE[MXLEWTIGM½IHXI\X1-1)X]TIIRGSHIHYWMRKIMXLIV9RMGSHI98*SV98* GLEVEGXIVIRGSHMRK WYGLEW<10 MRE1<*½PI²17 8LI;SVOMRK+VSYTMWMRXIVIWXIHMRXIGLRMGEPQIXEHEXEXLIQSZMRKMQEKIIUYMZEPIRXWXSETEMV SJWXERHEVHWJVSQXLI%YHMS)RKMRIIVMRK7SGMIX]  %)7 JSVXLGSQMRK XLIHVEJXJSVQ[EW PEFIPIH%)7<& XMXPIHAES standard for audio metadata - Audio object structures for preserva- tion and restoration ERH  %)7<' WXMPPSRP]MRHVEJX XMXPIHAdministrative metadata for audio objects - Process history schema8LIJSVQIVTVSZMHIWEHIWGVMTXMSRSJEKMZIR½PI´WXIGLRMGEP characteristics — not unlike the instantiation elements in PBCore18 — while the latter offers EHIWGVMTXMSRSJXLITVSGIWWXLEXGVIEXIHXLI½PI[LEXMWWSQIXMQIWGEPPIHdigital provenance-R the federal agencies effort, there is a subgroup devoted to technical metadata and their work is still under development.

8LIJIHIVEPEKIRGMIW;SVOMRK+VSYTHSIWRSXERXMGMTEXISJJIVMRKWMKRM½GERXVIGSQQIRHEXMSRW regarding descriptive metadata. The group includes representatives from both archive and li- FVEV]SVKERM^EXMSRW[MXLTVEGXMGIWJSVVIWSYVGIHIWGVMTXMSRXLEXZEV]MRWMKRM½GERX[E]W;MXL all types of materials, libraries favor bibliographic data while archives prefer ½RHMRKEMHW-RXLI end, we are likely to have more to say about where a chunk of agency-produced descriptive metadata might be embedded than about what it should look like. We also do not anticipate offering recommendations regarding structural metadata, beyond the structural option inherent in MXF itself. Different agencies and even units within agencies take a variety of approaches to content packaging — the binding or bundling of multiple related ½PIW;ILEZILS[IZIVHMWGYWWIHXLIMHIESJLEZMRKXLI1<*ETTPMGEXMSRWTIGM½GEXMSRJSVEV- chiving and preservation include a way to wrap collections, i.e., sets of items.

Conclusion %W[ITVSGIIHXLI;SVOMRK+VSYTMW[IPPE[EVIXLEX[IEVIEXERIEVP]WXEKIMRXLMWTVSG- ess, with comparatively little experience. We believe that there is value in drafting a thorough ETTPMGEXMSRWTIGM½GEXMSR°ERMQTSVXERXWXITMRXLIHMVIGXMSRSJWXERHEVHM^EXMSR&YX[I[MPP [EMXYRXMP[ILEZIQSVII\TIVMIRGIYRHIVSYVFIPXWFIJSVIQEOMRKE½VQVIGSQQIRHEXMSR to other archives. This thought has led us to explore some form of provisional advisory: “What shall we do in XLIQIERXMQI#²;ILEZILIEVHJVSQGSPPIEKYIW[LSXLMROMRKSJXLIMVZMHISXETIWMRHMVIRIIH of reformatting, are drawn to the practices at Stanford and Rutgers — mentioned earlier in XLMWTETIV°XLEXGVIEXI½PIW[MXLYRGSQTVIWWIHZMHISWXVIEQWMR[MHIP]YWIH[VETTIVWPMOI 5YMGO8MQIERH%:-1IER[LMPIJSVFSVRHMKMXEPGSRXIRXSXLIVGSPPIEKYIWLEZIWOIXGLIHTVS- visional plans to hold some newly arrived materials in their native video encodings, reckoning XLEXXLIWI[MPPVIQEMRTPE]EFPIJSVEJI[]IEVW8LI;SVOMRK+VSYTMWMRXIVIWXIHMRTVSZMWMSREP solutions like these and hopes to assemble an advisory in the foreseeable future.

16 http://store.smpte.org/product-p/st% 200410-2008.htm 17 http://store.smpte.org/product-p/rp%202057-2011.htm 18 http://pbcore.org/v2/elements/pbcoredescriptiondocument/pbcoreinstantiation

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