Methods and apparatus to increase a match rate for media identification

A tangible, non-transitory computer readable storage medium comprising instructions that, when executed, cause a machine to at least:

• generate, at a central facility, a first signature of a first portion of a first media element, wherein the first signature is a preliminary signature;
• receive, at the central facility, a second signature from monitored media elements;
• compare the second signature with the first signature;
• determine a number of hits associated with the first media element based on the comparison;
• and
• when the number of hits meets a threshold, generate, at the central facility, a third signature of the first media element, the third signature generated for a second portion of the first media element, wherein the third signature is an expanded version of the first signature.

A method comprising:

• generating, at a central facility, a first signature of a first portion of a first media element, wherein the first signature is a preliminary signature;
• receiving, at the central facility, a second signature from monitored media elements;
• comparing the second signature with the first signature;
• determining a number of hits associated with the first media element based on the comparison;
• and
• when the number of hits meets a threshold, generating, at the central facility, a third signature of the first media element, the third signature generated for a second portion of the first media element, wherein the third signature is an expanded version of the first signature.