A mark corresponding to recording data is formed on an optical disk by: encoding the recording data in accordance with a modulation code and generating encoded data; classifying the encoded data by a combination of at least two of a mark length of a mark, a space length of a preceding space, the mark length of a preceding mark, and the space length of a succeeding space; setting a correction amount for adjusting the position of the start edge and the end edge of a recording pulse based on an evaluation index of a decoding result, which is a result of decoding a reproduction signal of the encoded data, for each of the classification; and generating the recording pulse corresponding to the encoded data by using the correction amount corresponding to the classification of the run length of the encoded data.

A mark corresponding to recording data is formed on an optical disk by: encoding the recording data in accordance with a modulation code and generating encoded data; classifying the encoded data by a combination of at least two of a mark length of a mark, a space length of a preceding space, the mark length of a preceding mark, and the space length of a succeeding space; setting a correction amount for adjusting the position of the start edge and the end edge of a recording pulse based on an evaluation index of a decoding result, which is a result of decoding a reproduction signal of the encoded data, for each of the classification; and generating the recording pulse corresponding to the encoded data by using the correction amount corresponding to the classification of the run length of the encoded data.

A mark corresponding to recording data is formed on an optical disk by: encoding the recording data in accordance with a modulation code and generating encoded data; classifying the encoded data by a combination of at least two of a mark length of a mark, a space length of a preceding space, the mark length of a preceding mark, and the space length of a succeeding space; setting a correction amount for adjusting the position of the start edge and the end edge of a recording pulse based on an evaluation index of a decoding result, which is a result of decoding a reproduction signal of the encoded data, for each of the classification; and generating the recording pulse corresponding to the encoded data by using the correction amount corresponding to the classification of the run length of the encoded data.

A mark corresponding to recording data is formed on an optical disk by: encoding the recording data in accordance with a modulation code and generating encoded data; classifying the encoded data by a combination of at least two of a mark length of a mark, a space length of a preceding space, the mark length of a preceding mark, and the space length of a succeeding space; setting a correction amount for adjusting the position of the start edge and the end edge of a recording pulse based on an evaluation index of a decoding result, which is a result of decoding a reproduction signal of the encoded data, for each of the classification; and generating the recording pulse corresponding to the encoded data by using the correction amount corresponding to the classification of the run length of the encoded data.

Computing systems and methods for estimation and correction of audio pitch variations resulting from eccentric rotation in the playback of phonograph records are disclosed. The methods include simulation of phonograph playback to generate eccentric and non-eccentric time bases for correction. Estimation of eccentricity parameters is done by a parameter optimization through evaluation of a spectral sharpness detection function on time-spectral content of audio data. Candidate audio data are generated using phonograph simulation while conducting an optimal parameter search. The disclosed technology further provides systems and methods to correct audio using such parameters to correct the induced pitch variations from eccentric phonograph record playback in order to improve the pitch stability of audio recordings. In addition, the physical properties of groove radius and playback speed variations in phonograph playback may be estimated from the eccentric record playback.

Computing systems and methods for estimation and correction of audio pitch variations resulting from eccentric rotation in the playback of phonograph records are disclosed. The methods include simulation of phonograph playback to generate eccentric and non-eccentric time bases for correction. Estimation of eccentricity parameters is done by a parameter optimization through evaluation of a spectral sharpness detection function on time-spectral content of audio data. Candidate audio data are generated using phonograph simulation while conducting an optimal parameter search. The disclosed technology further provides systems and methods to correct audio using such parameters to correct the induced pitch variations from eccentric phonograph record playback in order to improve the pitch stability of audio recordings. In addition, the physical properties of groove radius and playback speed variations in phonograph playback may be estimated from the eccentric record playback.