Added on 2013-08-13: Here are the slides in PDF and ODP. The slide set is CC BY-ND, if you prefer.

I will be on a panel on Open Government Data at COSCUP this year (August 3-4, 2013). COSCUP (Conference for Open Source Coders, Users and Promoters) is the largest open source conference in Taiwan. I was also asked by the conference organizers to give another talk at the conference. I thought hard about it, not really sure if I should and what to talk about if I would.

At the end I decided to talk about metadata. The following is the title, abstract, and speaker bio I submitted to the conference organizers at the end of May. I will need much time preparing for this talk (too late to back out now). I may again talk about the same subject in another meeting this summer. This page will be a place where I document my progress in preparing this talk.

(Note: I decided on the title before it was revealed that the US National Security Agency was getting "telephony metadata" from millions of Verizon customers. In light of this development, I may detour a bit and touch upon communication metadata and privacy issues too.)



Metadata says a lot about the files you have or like to have. Metadata describes the contents of the files, and it gives them contexts. Without bibliographic data, you will not be able to search the library. When the Exif (Exchangeable image file format) data embedded in your photos is erased, you lose valuable information (do you still remember when you took those photo?). Web services and social networks host your files, but they are not reliable. In many cases, these services keep and grow metadata about and around your collections of files. They keep the metadata for you, and they hold on to it. Without the metadata, your files do not have contexts. Some social media sites even erase the metadata embedded in your photos when they are uploaded, and these sites are not very good at managing the metadata for you. [2] These sites want you to share your files with others using their services only; they make it difficult for you to move your collections and share them elsewhere.

What can you do? In this talk, we will give a general introduction to metadata, and the practices in using metadata to facilitate sharing. We advocate the position that we shall manage metadata ourselves, and metadata shall travel with files when they are shared. We will show some tools and services to help affirm such a position.

[1] With an apology to Toaplan, see <>.
[2] "Social Media sites: photo metadata test results", see <>.

About the Speaker: Tyng-Ruey Chuang is an associate research fellow at Academia Sinica, Taiwan, with a joint appointment at the Institute of Information Science and at the Research Center for Information Technology Innovation (CITI). He also teaches at the Department of Information Management, National Taiwan University, as an associate professor. His research areas include programming languages, Web technologies, geo-spatial informatics, and Internet and society.



後設資料是關於您的(或您想要取得的)檔案的重要資料。它描述檔案的內容,提供檔案的背景。沒有書目資料,在圖書館裡無法調閱書籍。如果照片內嵌的 Exif (可交換影像資料格式)資料被除去了,您也就失去了重要的資訊(拍照當時的時間,您還記得嗎?)。網路服務商以及人際媒體網站存有您的檔案,但這些網站並不可靠。在很多情形,這些服務商增添維護您所收藏檔案的後設資料。它幫您保管後設資料,但也把持這些資料。沒了這些資料,您的檔案就失去了背景。某些人際媒體網站甚至抹去您所上傳照片的內嵌後設資料,但這些網站也沒能為您好好地維護這些照片的後設資料。[2] 這些網站要您只透過它們來分享檔案;您要把檔案搬走到別處分享,可是困難重重。


[1] 謹向遊戲軟體廠商 Toaplan 公司致歉,參見: <>。
[2] "Social Media sites: photo metadata test results", 參見: <>。