American Memory Help

How to View

Many American Memory collections contain sound recordings, video, high-resolution images, and enhanced text that require special viewers. Most viewers can be downloaded free from vendor sites.

The links below explain the various formats used and how to access them.

Jump to:

Sound Recordings

Sound Recording Formats About the Format Players Samples
RealAudio
(.ra, .ram)
- Minimizes download time
- If you have trouble using RealAudio, download the most recent version of RealPlayer
Windows, Mac: RealPlayer - Sample RealAudio file
- About this sample
MP3
(MPEG 2, Layer 3, .mp3)
- Offers high-quality sound

- Downloads faster than WAV files
- Windows: Media Player

- Mac: QuickTime
Additional MP3 Players
- Sample MP3
- About this sample
WAV (WaveForm, .wav) - Higher-quality format

- Must download completely before playing

- Longer download time

- Windows operating systems contain WAV players

- Some browsers contain media players that play WAV files
- Windows: Media Player

- Mac: QuickTime
- Sample WAV
- About this sample

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Documents (Text and Page Images)

In general, no special viewers are required to view text in American Memory. Most images of historical documents, as well as transcriptions of documents, are displayed through your web browser.

Certain illustrations and higher-resolution images, however, require special formatting.

Document Formats About the Format Viewers Samples
TIFF
(Tagged Image File Format, .tif, .tiff)
Used for images of original pages - Windows TIFF viewers
Alternatiff
InterneTIFF
IrfanView
Quick View Plus

- Mac TIFF viewers
OSX: locate "Preview" on your computer
Graphic Converter
- Sample TIFF
- About this sample
PCX
(.pcx)
Used for images of original illustrations - Windows PCX viewers (pre-installed)
Find "kodakimg.exe"
MS Paintbrush. Find "mspaint.exe"

- Windows PCX viewers
Windows: IrfanView
Windows: Quick View Plus
Mac: Graphic Converter
- Sample PCX
- About this sample
PDF
(Portable Document Format, .pdf)
Used for page images Adobe Acrobat Reader

Adobe text-only download page
- Sample PDF
- About this sample
MrSID
(Multi-resolution Seamless Image Database, .sid)
- Used for page images

- Wavelet compression technology

- Decompresses only that portion of the image requested by the user
MrSID viewer - Sample MrSID document
- About this sample
SGML
(Standard Generalized Markup Language, .sgm)
- Enhanced search and browse features (including linked table of contents)

- Viewing illustrations within SGML files requires the TIFF/PCX tools listed above.
No current SGML viewer is available for download.

Download an older, free SGML viewer for Windows from the Oasis XML Consortium.
- Sample SGML
- About this sample

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Maps

Maps and other large images in American Memory are presented as GIF or JPEG files and require no special viewers, unless you choose to download and view maps offline.

For off-line viewing, some maps are available in the MrSID format and others are available in the JPEG2000 format.

Download and View Maps Offline

Map Format About the Format Viewer Samples
MrSID
(.sid)
- Wavelet compression technology

- Decompresses only that portion of the image requested by the user

- Compression ratio is approximately 22:1, depending on image content and color depth
- MrSID viewer
- IrfanView with plug-ins
- Sample MrSID map
- About this sample
JPEG2000
(.jp2)
- Wavelet compression technology

- Tiling supports decompression of only that portion of the image requested by the user

- Compression ratio is approximately 20:1, depending on image content and color depth
Windows:
- ER Viewer 7.0
- IrfanView with plug-ins

OS X:Preview supports baseline JP2 only; commercial software may be needed to view tiled JP2 files
- Sample JPEG2000 map
- About this sample

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Prints and Photographs

Most prints and photographs in American Memory are displayed in GIF and JPEG formats and require no special viewers. Some images are also offered as TIFFs—higher-resolution images with larger file sizes that require additional software.

Print, Photograph Formats About the Format Viewers Samples
TIFF
(Tagged Image File Format, .tif, .tiff)
Used for images of original prints and photographs - Windows TIFF viewers
Alternatiff
InterneTIFF
IrfanView
Quick View Plus

- Mac TIFF viewers
OSX: locate "Preview" on your computer
Graphic Converter
- Sample TIFF photo
- About this sample

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Video

American Memory video collections are available in the following formats:

Motion Picture Formats About the Format Players Video
MPEG
(Motion Picture Experts Group, .mpg, .mpeg)
- Highest-quality files are in the MPEG format

- Average file size is about nine megabytes for each minute of motion picture
Windows: Media Player
Mac: QuickTime
Additional MPEG players
- Sample MPEG
- About this sample
QuickTime
(.mov)
- QuickTime (Cinepak compression)

- Offers smaller, downloadable files and allows films to be viewed on lower-end computers

- Not as crisp as the MPEG format

- Average file size is about five megabytes for each minute of motion picture

- QuickTime 3 (Sorenson compression)

- A streaming file format
Enhanced image quality, higher resolution

- Available in Dance Instruction Manuals collection

- Average file size is about six megabytes for each minute of motion picture
Windows, Mac: QuickTime
Windows: Media Player
QuickTime
- Sample QuickTime
- About this sample

QuickTime 3
- Sample QuickTime 3
- About this sample
RealMedia
(.rm, .ram)
- A streaming file format

- Useful for computers with slower Internet connections

- Playback is slower (three to six frames per second) and may be affected by Internet traffic.
Windows, Mac: RealPlayer - Sample RealMedia
- About this sample

More Information about Downloading and Viewing Video

Video clips longer than four minutes may have been segmented, thereby limiting maximum file size to approximately 40 MB. A typical 28.8 Internet connection achieves a theoretical maximum download rate of approximately 3.5 KB/sec (210 K/min) under ideal conditions. Therefore, a file of 40 MB would take approximately 190 minutes (three hours, ten minutes) under optimal conditions, depending on Internet traffic.

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