CORPORA from CSLU: Numbers v1.3

Case ID:
Web Published:

Technology 0681-L, the Numbers Corpus is a collection of naturally produced numbers. The utterances were taken from other CSLU telephone speech data collections, and include isolated digit strings, continuous digit strings, and ordinal/cardinal numbers. A total of 23902 files are included in this corpus.


Recording Details:
The data in this corpus were collected over telephone lines. They were collected from both analog and digital phone lines.

The analog data were recorded using a Gradient Tehcnologies analog-to- digital conversion box. These files were recorded as 16-bit, 8 khz and stored in a linear format.

The digital data were recorded with the CSLU T1 digital data collection system. These files were sampled at 8 khz 8-bit and stored as ulaw files.

All of the data have been linearly encoded in the 16-bit RIFF standard file format.

Directory Structure:
There are five top-level directories in this distribution: docs, speech, labels, trans, and misc. The docs directory contains assorted documentation files.

The speech, trans, and labels directories contain the data files, which have the following name structure:





xxxxx = call number


y = utterance code


zzz = file extension (txt/wav/phn)

For example:


This utterance is from caller 1016 and contains numbers from a street address.

Corresponding text and phonetic transcriptions can be found in these files:



These audio and text files are subdivided into directories based on their call number div 100. So, these files would be found in /numbers/speech/10,, /numbers/trans/10, and /numbers/labels/10, respectively.

The text transcriptions were performed according to the non time-aligned word-level conventions described in the CSLU Labeling Guide.

Phonetic transcriptions are plain text files that carry time-aligned phonetic labels. The first two lines of the file are a header, which defines the length of a "frame" in milliseconds. The rest of the files consists of two numbers that define a frame range, and a label that applies to that region. For example:

                                         MillisecondsPerFrame: 1.000000

                                         END OF HEADER

                                         2 113 .pau

                                         113 191 w

                                         191 267 ^

                                         267 395 n       


So, we can see here that a frame corresponds to 1 millisecond (ms) of time, and that from 2 to 113 ms into the file, there is a pause (.pau), with the first phoneme (w) starting at 113 ms and stretching to 191 ms.

The Center for Spoken Language Understanding (CSLU) distributes corpora to commercial entities and academic institutions for a fee. Commercial entities can use these corpora for research but also for creating commercial products such as generating acoustic models for speech recognition.


To place your order:

1. Click on the type of license you wish to order. The Academic or non-profit entity fee is $50; Commercial entity fee is $2,500.

2. Terms of the license agreement can be viewed by clicking on the word "terms".

3. You agree to the terms of the license agreement when you click on "Add to Order" and proceed to the next screen.

4. If information on the "Order Contents" screen is correct, press "Check out".

5. On the next screen, a brief "Intended Use" is required. For "Recipient Scientist Information" enter the appropriate information for yourself or if you are placing the order for another person enter that information. We will use this information should we have questions about the order, payment or shipping address.

6. Once your payment has been received and verified by OHSU, your order will be approved by Technology Transfer & Business Development and then the DVD will be sent out by the Center for Spoken Language Understanding by FedEx within 5-10 business days.  


For more information, visit the CSLU Corpora website at:


Files will be made available by download from which requires customers to set up a free account. 


Patent Information:
Speech & Language
For Information, Contact:
Arvin Paranjpe
Technology Development Manager
Oregon Health & Science University
(503) 494-8200
Education & Training
Education & Training - Speech & Language
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