Data compression method
View Patent ↗A method for transmitting the value of a parameter in a compressed form, the method comprising the steps of: accepting successive numbers representing the value of a parameter; manipulating each number, the manipulation comprising placing the number in a form comprising a mantissa and an exponent, and defining a transmission mantissa to be transmitted; transmitting to a receiver, in turn, the transmission mantissas only of the successive numbers; and receiving the transmission mantissas of the successive numbers at the receiver, characterised by the steps of maintaining a record, at the receiver, of a receiver variable, the receiver variable initially corresponding to the exponent of an initial number; formulating at the receiver, for each received transmission mantissa, a reconstructed number comprising at least the transmission mantissa and an exponent corresponding to the receiver variable; and altering the receiver variable in a first manner if the transmission mantissa of the current number fulfils a first criterion, or altering the receiver variable in a second manner if the transmission mantissa of the current number fulfils a second criterion.
1. A method for transmitting a value of a parameter in a compressed form, the method comprising the steps of:
accepting successive numbers representing the value of the parameter;
manipulating each of the successive numbers, the manipulation comprising the steps of placing the number in a form comprising a mantissa and an exponent, and defining a transmission mantissa to be transmitted;
transmitting to a receiver, the transmission mantissas only of the successive numbers; and
receiving the transmission mantissas of the successive numbers at the receiver;
maintaining a record, at the receiver, of a receiver variable, the receiver variable initially corresponding to the exponent of an initial number;
formulating at the receiver, for each received transmission mantissa, a reconstructed number comprising at least the transmission mantissa and an exponent corresponding to the receiver variable; and
altering the receiver variable in a first manner if the transmission mantissa of the current number fulfills a first criterion, or altering the receiver variable in a second manner if the transmission mantissa of the current number fulfills a second criterion.
2. The method according to claim 1 , wherein:
the step of manipulating comprises the step of defining the transmission mantissa as being at least a part of the mantissa, if the mantissa is below a first predetermined value, or defining the transmission mantissa as being equal to the first predetermined value if the mantissa is equal to or greater than the first predetermined value;
wherein the transmission mantissa of the current number fulfills the first criterion when the transmission mantissa is equal to the first predetermined value; and
wherein altering the receiver variable in the first manner comprises increasing the receiver variable incrementally.
3. The method according to claim 2 , wherein:
a record is maintained at the transmitter of a transmitter variable, the transmitter variable initially corresponding to the exponent of an initial number;
the step of placing each number in a form comprising a mantissa and an exponent further comprises the step of defining the exponent as being equal to the transmitter variable; and
the transmitter variable is increased incrementally whenever the transmission mantissa is equal to or greater than the first predetermined value.
4. The method according to claim 2 , wherein the first predetermined value comprises the highest value of the transmission mantissa.
5. The method according to claim 1 , wherein:
the manipulation further comprises the step of defining the transmission mantissa as being at least a part of the mantissa if the mantissa is greater than a second predetermined value, or defining the transmission mantissa as being equal to the second predetermined value if the mantissa is equal to or less than the second predetermined value;
the transmission mantissa of the current number fulfills the second criterion when the transmission mantissa is equal to the second predetermined value; and
altering the receiver variable in the second manner comprises decreasing the receiver variable incrementally.
6. The method according to claim 5 , wherein:
a record is maintained, at the transmitter of a transmitter variable, the transmitter variable initially corresponding to the exponent of an initial number;
the step of placing each number in a form comprising a mantissa and an exponent further comprises the step of defining the exponent as being equal to the transmitter variable; and
the transmitter variable is incrementally decreased whenever the transmission mantissa is equal to or less than the second predetermined value.
7. The method according to claim 5 , wherein the second predetermined value comprises the lowest value that the transmission mantissa may take.
8. The method according to claim 1 , wherein:
the step of manipulating comprises the step of defining the transmission mantissa as being at least a part of the mantissa;
the transmission mantissa of the current number fulfills the second criterion when the first x significant digits of the transmission mantissa are 0; and
altering the receiver variable in the second manner comprises decreasing the receiver variable by x.
9. The method according to claim 8 , further comprising the step of:
maintaining a record at the transmitter of a transmitter variable, the transmitter variable initially corresponding to the exponent of an initial number;
the step of placing each number in a form comprising a mantissa and an exponent further comprises the step of defining the exponent as being equal to the transmitter variable; and
the transmitter variable is decreased by x whenever the first x significant digits of the transmission mantissa are 0.
10. The method according to claim 1 , wherein the step of altering the receiver variable in a first or second manner occurs after the step of formulating a reconstructed number.
11. The method according to claim 1 , wherein:
the transmission mantissa of the current number fulfills the first criterion if the transmission mantissa of the current number is less than the transmission mantissa of the previous number by more than a first predetermined amount; and
altering the receiver variable in the first manner comprises increasing the receiver variable incrementally.
12. The method according to claim 11 , wherein the step of altering the receiver variable in a first or second manner occurs before the step of formulating a reconstructed number.
13. The method according to claim 11 , wherein:
the step of placing each number in a form comprising a mantissa and an exponent comprises the step of defining a mantissa in a digital form in which the most significant digit of the mantissa is 1, the remaining digits comprising a characteristic portion; and
the step of defining a transmission mantissa comprises defining a transmission mantissa being equal to the characteristic portion.
14. The method according to claim 11 , wherein a low pass filter is applied to the successive numbers, to limit the difference between the successive numbers.
15. The method according to claim 1 , wherein:
the transmission mantissa of the current number fulfills the second criterion if the transmission mantissa of the current number is greater than the transmission mantissa of the previous number by more than a second predetermined amount; and
altering the receiver variable in the second manner comprises decreasing the receiver variable incrementally.
16. The method according to claim 15 , wherein the step of altering the receiver variable in a first or second manner occurs before the step of formulating a reconstructed number.
17. The method according to claim 15 , wherein:
the step of placing each number in a form comprising a mantissa and an exponent comprises the step of defining a mantissa in a digital form in which the most significant digit of the mantissa is 1, the remaining digits comprising a characteristic portion; and
the step of defining a transmission mantissa comprises defining a transmission mantissa being equal to the characteristic portion.
18. The method according to claim 15 , wherein a low pass filter is applied to the successive numbers, to limit the difference between the successive numbers.
19. A method of receiving values of a parameter in a compressed form, the method comprising the steps of:
receiving transmission mantissas of successive numbers, the numbers representing the value of a parameter at a receiver;
maintaining a record at the receiver, of a receiver variable, the receiver variable initially corresponding to the exponent of an initial number;
formulating at the receiver, for each received transmission mantissa, a reconstructed number comprising at least the transmission mantissa and an exponent corresponding to the receiver variable; and
altering the receiver variable in a first manner if the transmission mantissa of the current number fulfills a first criterion, or altering the receiver variable in a second manner if the transmission mantissa of the current number fulfills the second criterion.
20. A receiver apparatus for receiving values of a parameter in a compressed form, the receiver apparatus comprising:
a processor being configured to receive transmission mantissas of successive numbers representing the value of a parameter;
the processor being configured maintain a record of a receiver variable, the receiver variable initially corresponding to the exponent of an initial number;
the processor being configured to formulate, for each received transmission mantissa, a reconstructed number comprising at least the transmission mantissa and an exponent corresponding to the receiver variable; and
the processor being configured to alter the receiver variable in a first manner if the transmission mantissa of the current number fulfills a first criterion, or alter the receiver variable in a second manner if the transmission mantissa of the current number fulfills a second criterion.
21. A method for transmitting a value of a parameter in a compressed form, the method comprising the steps of:
accepting successive numbers representing the value of the parameter;
manipulating each number, the manipulation comprising the steps of placing the number in a form comprising a mantissa and an exponent, and defining a transmission mantissa as being at least a part of the mantissa if the mantissa is below a first predetermined value, or defining the transmission mantissa as being equal to the first predetermined value if the mantissa is equal to or greater than the first predetermined value;
transmitting to a receiver, in turn, the transmission mantissas only of the successive numbers; and
receiving the transmission mantissas of the successive numbers at the receiver, characterized by the steps of:
maintaining a record at the receiver of a receiver variable, the receiver variable initially corresponding to the exponent of an initial number;
formulating at the receiver for each received transmission mantissa, a reconstructed number comprising at least the transmission mantissa and an exponent corresponding to the receiver variable; and
increasing the receiver variable incrementally if the transmission mantissa of the current number is equal to the first predetermined value, or altering the receiver variable in a second manner if the transmission mantissa of the current number fulfills a second criterion.