Waveform-forming device having memory storing non-compressed/compressed waveform samples

Claim 2

A waveform-forming device for forming waveforms of musical tones, comprising: waveform memory means for storing a plurality of blocks of waveform samples representative of a waveform of a musical tone, each block being formed of at least one non-compressed waveform sample and a plurality of compressed waveform samples; reading means for reading said waveform samples block by block, from said waveform memory means, based on a pitch of a musical tone to be formed; converting means for converting said compressed waveform samples contained in each block, read by said reading means, into non-compressed waveform samples; and waveform-forming means for forming said waveform of said musical tone from said at least one non-compressed waveform sample of said each block and said non-compressed waveform samples obtained by said converting means.

Claim 3

A waveform-forming device according to claim 1, further comprising pitch-designating means for designating said pitch of said musical tone to be formed.

Claim 4

A waveform-forming device according to claim 1 or 2, wherein said reading means reads out said waveform samples at a frequency irrespective of a frequency of a waveform to be formed, the device further comprising: interpolating means for performing interpolation on said non-compressed waveform samples contained in said each block and obtained by conversion of said converting means, to form said waveform of said musical tone, a number at least m-1 of waveform samples located at a tail portion of said each block being identical with a number at least m-1 of waveform samples located at a head portion of an immediately subsequent block thereof, when said interpolating means performs interpolation by the use of a number m of waveform samples.

Claim 5

A waveform-forming device for forming waveforms of musical tones, comprising: waveform memory means for storing non-compressed waveform samples located at intervals of a predetermined number of sampling points, and compressed waveform samples each located between adjacent ones of said non-compressed waveform samples; frequency information-generating means for generating information on a frequency corresponding to a pitch of a musical tone to be formed; cumulating means for cumulating said frequency information at a predetermined speed to output a cumulative value; reading means for reading, based on said cumulative value, a non-compressed waveform sample and a plurality of compressed waveform samples subsequent to said non-compressed waveform sample, from said waveform memory means; and converting means for converting said plurality of compressed waveform samples read by said reading means into non-compressed waveform samples using said non-compressed waveform sample.

Claim 6

A waveform-forming device for forming waveforms of musical tones, comprising: waveform memory means for storing non-compressed waveform samples located at intervals of a predetermined number of sampling points, and compressed waveform samples each located between adjacent ones of said non-compressed waveform samples; frequency information-generating means for generating information on a frequency corresponding to a pitch of a musical tone to be formed; cumulating means for cumulating said frequency information at a predetermined speed to output a cumulative value; reading means for reading, based on said cumulative value, a non-compressed waveform sample and a plurality of compressed waveform samples subsequent to said non-compressed waveform sample, from said waveform memory means; and converting means for converting said plurality of compressed waveform samples read by said reading means into non-compressed waveform samples using said non-compressed waveform sample.

Claim 7

A waveform-forming device according to claim 4, further comprising: selecting means for selecting, based on said cumulative value, non-compressed waveform samples to be used for interpolation, out of said non-compressed waveform sample and said plurality of non-compressed waveform samples.

Claim 8

A waveform-forming device according to claim 4, further comprising: interpolating means for performing interpolation, based on said cumulative value, on non-compressed waveform samples selected by said selecting means, to output a result of said interpolation as a waveform sample of a musical tone.

Claim 9

A waveform-forming device for forming waveforms of musical tones, comprising: waveform memory means storing non-compressed waveform samples located at intervals of a predetermined number of sampling points, and compressed waveform samples each located between adjacent ones of said non-compressed waveform samples; frequency information generating means for generating information on a frequency corresponding to a pitch of a musical tone to be formed; cumulating means for cumulating said information at a predetermined speed to output a cumulative value; reading means for reading, based on said cumulative value, a plurality of non-compressed waveform samples and compressed waveform samples sequentially arranged, from said waveform memory means; converting means for converting said compressed waveform samples read by said reading means into non-compressed waveform samples in a manner such that said compressed samples are converted by the use of an immediately preceding one of said non-compressed waveform samples; selecting means for selecting, based on said cumulative value, non-compressed waveform samples to be used for interpolation, out of said non-compressed waveform samples obtained by reading means and said non-compressed waveform samples obtained by said converting means; and interpolating means for performing interpolation, based on said cumulative value, on non-compressed waveform samples selected by said selecting means, to output results of said interpolation as a waveform of a musical tone.

Claim 10

A waveform-forming device for forming waveforms of musical tones, comprising: waveform memory means storing non-compressed waveform samples located at intervals of a predetermined number of sampling points, and compressed waveform samples each located between adjacent ones of said non-compressed waveform samples; frequency information generating means for generating information on a frequency corresponding to a pitch of a musical tone to be formed; cumulating means for cumulating said information at a predetermined speed to output a cumulative value; reading means for reading, based on said cumulative value, a plurality of non-compressed waveform samples and compressed waveform samples sequentially arranged, from said waveform memory means; converting means for converting said compressed waveform samples read by said reading means into non-compressed waveform samples in a manner such that said compressed samples are converted by the use of an immediately preceding one of said non-compressed waveform samples; selecting means for selecting, based on said cumulative value, non-compressed waveform samples to be used for interpolation, out of said non-compressed waveform samples obtained by reading means and said non-compressed waveform samples obtained by said converting means; and interpolating means for performing interpolation, based on said cumulative value, on non-compressed waveform samples selected by said selecting means, to output results of said interpolation as a waveform of a musical tone.

Claim 11

A waveform-forming device for forming a waveform of a musical tone, comprising: waveform memory means for storing non-compressed waveform samples located at intervals of a predetermined number of sampling points, and compressed waveform samples each located between adjacent ones of said non-compressed waveform samples; converting means for converting said compressed samples into non-compressed waveform samples by the use of immediately preceding one of said non-compressed waveform samples; and tone forming means for forming a waveform of a musical tone in accordance with said non-compressed waveform samples converted by said converting means and said non-compressed waveform samples stored in said waveform memory means.

Claim 12

A waveform-forming device for forming a waveform of a musical tone, comprising: waveform memory means for storing non-compressed waveform samples located at intervals of a predetermined number of sampling points, and compressed waveform samples each located between adjacent ones of said non-compressed waveform samples; converting means for converting said compressed samples into non-compressed waveform samples by the use of immediately preceding one of said non-compressed waveform samples; and tone forming means for forming a waveform of a musical tone in accordance with said non-compressed waveform samples converted by said converting means and said non-compressed waveform samples stored in said waveform memory means.