Switchboard Cellular Part 1 Transcribed Audio

Item Name: Switchboard Cellular Part 1 Transcribed Audio
Author(s): David Graff, Kevin Walker, David Miller
LDC Catalog No.: LDC2001S15
ISBN: 1-58563-215-5
ISLRN: 183-382-664-496-3
Member Year(s): 2001
DCMI Type(s): Sound
Sample Type: 2-channel ulaw
Sample Rate: 8000
Data Source(s): telephone conversations
Project(s): SID, GALE, EARS
Application(s): speaker identification
Language(s): English
Language ID(s): eng
License(s): LDC User Agreement for Non-Members
Online Documentation: LDC2001S15 Documents
Licensing Instructions: Subscription & Standard Members, and Non-Members
Citation: Graff, David, Kevin Walker, and David Miller. Switchboard Cellular Part 1 Transcribed Audio LDC2001S15. DVD. Philadelphia: Linguistic Data Consortium, 2001.


Switchboard Cellular Part 1 Transcribed Audio was developed by the Linguistic Data Consortium (LDC) and consists of approximately 24 hours of English telephone conversations collected by LDC between 1999-2000. This release contains the speech data files that correspond to Switchboard Cellular Part 1 Transcription (LDC2001T14).

The full set of conversations (approximately 109 hours) from the Switchboard Part 1 study is available in Switchboard Cellular Part 1 Audio (LDC2001S13). Switchboard Cellular Part 2 Audio (LDC2004S07) contains approximately 200 hours of English telephone conversations collected by LDC in the Switchboard Part 2 study.

The Switchboard Part 1 cellular collection focused primarily on GSM cellular phone technology. The project's goal was to target 190 subjects balanced by gender and under varied environmental conditions to participate in (10+) five to six minute conversations on GSM cellular phones. The speech data was collected for research, development, and evaluation of automatic systems for speech-to-text conversion, talker identification, language identification and speech signal detection purposes.


Each speech file consists of a 1,024-byte ASCII-formatted Sphere header, followed by two-channel interleaved mu-law sample data. The mu-law samples represent the actual digital data transmission from the telephone service provider (MCI), as captured separately for each side of the telephone conversation by LDC's telephone collection platform. The header also indicates the caller_pin, callee_pin, topic_id, cellular service/handset information and speaker demographic information. The documentation also contains reports on clipped files.


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