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Detect chords.


Parameter Type Description
access_id required string
One of your personal access_ids.
input_file required file
A file id or file url or a direct file upload (requires POST).

Upload a local file by performing a POST request with encoding-type "multipart/form-data" (corresponding to an html form with an <input type="file" />)

begin_seconds optional float
Skip audio data before this position.
end_seconds optional float
Ignore audio data after this position.
blocking optional bool
[true, false] default: true
Whether to call the task in a blocking or non-blocking way.

Blocking calls return the results directly. For more info see the response documentation for this task.

format optional string
[xml, json, jsonp, xmlp] default: xml
The format to use in the response.

Note that for the formats "jsonp" or "xmlp", the HTTP status code will always be 200.

callback optional string
Callback function name required when using the format "jsonp" or "xmlp."
foo_string optional string
Arbitrary string to add to the logs.

Allows you to add any strings you might find helpful for later analysis of the request logs.



The response gives you a status code, the file_id and the corresponding download URL of the resulting file (audio for process tasks and xml for analyze tasks). For processing reports, use the /file/status request with the parameter format=xml/json/jsonp/xmlp.

Name Description
status The status code of the task.
file_id The unique identifier of the file.
href The direct download link to the file including the file_id


The response gives you a list of detected chords with the following attributes:

Name Type Description
index integer The index.
time float The time.
chord string The chord in the format "root note : type".

Supported chord types

Abbreviation Description
N no chord
maj major
min minor
dim diminished
aug augmented
maj7 major seventh
min7 minor seventh
7 seventh
dim7 dimished seventh
hdim7 half diminished seventh
maj6 major sixth
min5 minor sixth