About NYPL Digital Gallery Project

Project History

NYPL Digital Gallery is The New York Public Library's image database, developed to provide free and open online access to hundreds of thousands of images from the original and rare holdings of The Library. Spanning a wide range of historical eras, geography, and visual media, NYPL Digital Gallery offers digital images of drawings, illuminated manuscripts, maps, photographs, posters, prints, rare illustrated books, and more. Encompassing the subject strengths of the vast collections of The Library, these materials represent the applied sciences, fine and decorative arts, history, performing arts, and social sciences.


Some examples of this far-ranging content include artwork such as Goya's Disasters of War; panoramic cityscapes of New York City's Fifth Avenue; classic illustrated zoologies and botanies such as Pomona Britiannica; George Caitlin's North American Indian Portfolio; Felice Beato's photographs of Japan; reformer Thomas A. Larcom's portrait collection from Dublin's Mountjoy prison; theatrical documentation including the Theatre Guild's first performance of Porgy in 1927; decorative arts in fine pochoir prints of the same era; and rare illustrated books such as William Blake's hand-printed masterpiece of 1793, America a Prophecy.

Also included are 16th-century maps and drawings depicting the landing of European explorers in the Western Hemisphere; contemporaneous engravings of battle scenes of the American Revolution; portraits of African Americans in the mid-19th century; photographs recording the westward progress of the American transcontinental railroad; sheet music covers and restaurant menus from the 1890s; and photographs of Depression-era New York City by Lewis Hine and Berenice Abbott.

Digitized collections include: The Samuel Putnam Avery Collection of etchings and lithographs from the 19th century, by French and other European and American artists, including Edouard Manet and Gustav Courbet; The Phelps Stokes Collection of American Historical Views -- drawings, topographical views and townscapes documenting 400 years of American history; the Lawrence H. Slaughter Collection of English maps, charts, globes, books and atlases emphasizing 17th- and 18th-century English Colonial North America; the William Augustus Spencer Collection of Illustrated Books, Manuscripts and Fine Bindings focusing on medieval and Renaissance illuminated manuscripts and on French bindings; and, the Vandamm Studio Collection photographs, recording theatre productions in New York City in the first half of the 20th century.

NYPL Digital Gallery will continue evolving as more visual collections are added. At over half a million images, the collections in NYPL Digital Gallery represent a small fraction of the New York Public Library's overall visual holdings.

Digital Images

For each item in NYPL Digital Gallery, a high-resolution, 300- to 1200-dpi digital image file has been created using a flatbed scanner or a digital camera. Each file is named at the time of capture with a unique number tying it to its respective descriptive record. Destined for archival storage, these original digital "captures" are not altered, enhanced or otherwise corrected, creating a record of an item's authentic appearance and condition; nor are the "archival" files cropped, in order to retain accompanying written or printed information.

Simultaneously, three low-resolution, 72-dpi "derivative" files are created for delivery on the web, at 150 pixels (thumbnail or index image), 300 pixels (detail view) and 760 pixels (enlargement), respectively, on the long side. The service files for creating the derivatives (copies of the archivals) are cropped not only to eliminate the routine color calibration bars but sometimes also to reduce very wide borders which bear no image or printed information, much as picture framers routinely overmat the borders of photographs and prints. On occasion, service files are enhanced to ensure better readability of the resulting derivative files. In addition, digital images of especially important, large, oddly-shaped or difficult-to-read items have been processed for image-compression delivery making it possible to enlarge and browse their fine details on the desktop.

High-resolution images are available for licensing for personal use and for professional reproduction through Photographic Services and Permissions; the low-resolution web images available on the website are suitable for immediate printing or downloading to provide good-quality reference copies for a wide range of creative, research, and educational purposes.

The Library's digital project team has captured and processed primarily those materials too valuable, vulnerable, or irregular to be managed in a production environment. The balance - typically large collections of very similar materials - was digitized by two imaging contractors, both on-site and in facilities off-site. Library staff process and add many images daily. The metadata records and associated images on the website are updated twice monthly.

IT Architecture and Delivery

NYPL Digital Gallery runs on an open, extensible architecture designed by the Digital Library Program and managed in conjunction with the Library's Information Technology Group. Image files are stored on a 57-terabyte network of servers (1 terabyte = 1,000 gigabytes, or 1 trillion bytes). Together, the image files and the data hierarchy and structure are managed through an Oracle database. A systematic XML extract of this data is indexed with the Java open-source search engine Lucene, which provides the public search matrix. ColdFusion software provides the application programming interface that integrates metadata and images for web delivery, via a website interface developed with consultant support by the Digital Library Program.

Editor: Liu xiongfei