CALLHOME American English Speech

Item Name: CALLHOME American English Speech
Author(s): Alexandra Canavan, David Graff, George Zipperlen
LDC Catalog No.: LDC97S42
ISBN: 1-58563-111-6
ISLRN: 952-976-147-406-5
Member Year(s): 1997
DCMI Type(s): Sound
Sample Type: 2-channel ulaw
Sample Rate: 8000
Data Source(s): telephone conversations
Project(s): Hub5-LVCSR, GALE, EARS
Application(s): speech recognition
Language(s): English
Language ID(s): eng
License(s): LDC User Agreement for Non-Members
Online Documentation: LDC97S42 Documents
Licensing Instructions: Subscription & Standard Members, and Non-Members
Citation: Canavan, Alexandra, David Graff, and George Zipperlen. CALLHOME American English Speech LDC97S42. Web Download. Philadelphia: Linguistic Data Consortium, 1997.
Related Works: View


CALLHOME American English Speech was developed by the Linguistic Data Consortium (LDC) and consists of 120 unscripted 30-minute telephone conversations between native speakers of English.

All calls originated in North America; 90 of the 120 calls were placed to various locations outisde of North America, while the remaining 30 calls were made within North America. Most participants called family members or close friends.


This corpus contains speech data files with documentation describing their contents and format along with the software packages needed to uncompress the speech data. Corresponding transcripts and documentation (LDC97T14) are available separately, as is an associated lexicon (LDC97L20).


Please listen to this audio sample.


The "shorten" and "sphere" directories have been removed.

The sphere directory contained NIST "SPeech HEader REsources" (SPHERE): C-language source code libraries and utilities for manipulating NIST SPHERE-format waveform files.

The shorten directory contained files for the "shorten" software for speech compression.

A more recent version of SPHERE utilities is available on the NIST web site; additional utilities for converting SPHERE files are also available from LDC's web site.

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