Automatic selection of encoding parameters to control length of time to encode and send data over network

1. An apparatus for data processing including encoding and sending, comprising:

an encoder encoding data using a selected one of a plurality of encoding parameter sets:

a transmitter transmitting the encoded data to a receiver via a communication network;

a condition-identifying device identifying an original data set for which the data processing is to be initiated at a start time t 0 , and identifying a deadline time t L by which the data processing is to be completed, wherein the original data set is one data sub-set or a sequence of two or more data sub-sets;

an assigned-time calculator calculating a length of an assigned time not exceeding a time limit (=t L −t 0 ) for the original data set, per each data sub-set;

a processing-time calculator calculating an estimate of an individual processing time T P to encode and send each data sub-set using a successively-selected one of the plurality of encoding parameter sets, per each data sub-set, based on the assigned time for the each data sub-set, an estimate of an encoding time T E to encode the each data sub-set using the successively-selected one encoding parameter set, and an estimate of a sending time T T to send the encoded data sub-set at a transmission rate; and

an encoding-parameter selector selecting one of the plurality of encoding parameter sets to allow a total processing time to fall within a shortened time limit (=α·t L −t 0 , 0<α<1) that is equal to the time limit (=t L −t 0 ) minus a marginal time,

wherein the total processing time, if the original data set is one data sub-set, is equal to the individual processing time for the one data sub-set, or if the original data set includes a sequence of two or more data sub-sets, is equal to a total of the individual processing times for the two or more data sub-sets.

2. The apparatus according to claim 1 , wherein the original data set includes a video data set,

the at least one encoding parameter includes one or more of the followings:

a ratio of frames to be encoded using intra-frame prediction in a spatial field;

a ratio of frames to be encoded using inter-frame prediction;

a size of search for inter-frame prediction;

a type of an algorithm for inter-frame prediction;

a size of quantization parameters;

a factor for pixel subsampling;

a factor for chroma subsampling;

a number of frames per a unit time;

a type of an encoding algorithm for data compression;

a type of frequency transformation of pixels;

a video format;

an image size (image resolution);

a frame rate; and

a bit rate for encoding.

3. The apparatus according to claim 2 , wherein the assigned-time calculator calculates, if the original data set are a sequence of two or more data sub-sets, the length of the assigned time for each of data sub-set, based on one or more of the followings: a play-back-time ratio, an image-size ratio, a frame-rate ratio, and a bit-rate ratio, between the data sub-sets within the original data set.

4. The apparatus according to claim 1 , further comprising a transmission-rate detector measuring the transmission rate at which data flows over the network, during a process of sending the encoding data.

5. The apparatus according to claim 4 , wherein the transmission-rate detector samples transmission rates in a plurality of different time zones within a day or a few days, and calculates a representative transmission rate based on the sampled transmission rates.

6. The apparatus according to claim 1 , wherein the encoding-parameter selector selects one of the plurality of encoding parameter sets, which allows the total processing time to end at a time closer to an advanced deadline time (=α·t L ), than any other parameter sets.

7. The apparatus according to claim 1 , further comprising:

a performance detector causing the encoder to encode test data, using a successively-selected one of the plurality of encoding parameter sets, measuring an encoding time to encode the test data, and obtaining an encoding time to encode a portion of the original data set which has a unit size; and

an encoding-time storage storing encoding times obtained by the performance detector, in association with the respective encoding parameter sets,

wherein the processing-time calculator calculate the processing time by reference to the encoding times stored in the encoding-time storage.

8. The apparatus according to claim 4 , further comprising an encoding-parameter changer activating the processing-time calculator and the encoding-parameter selector again, at a time when the transmission-rate detector measures the transmission rate lower than a predetermined threshold, during a process of sending the encoded data, and/or at a time when an integral amount of data that was sent for a given time period becomes smaller by above a predetermined value, than an initially-estimated amount of data, during a process of sending the encoded data.

9. The apparatus according to claim 8 , wherein the transmission-rate detector measures the transmission rate periodically, and/or

the transmission-rate detector measures the transmission rate, at one or more of the followings:

a time when encoding the original data set is completed,

a time during which encoded data is being sent,

a time when sending the encoded data is completed,

a time when a percentage of the encoding operation that has been finished reaches a given value,

a time when a percentage of the sending operation that has been finished reaches a given value, and

a time when a percentage of the entire data processing operation that has been finished reaches a given value, and

the encoding-parameter changer estimates the transmission rate at a subsequent time, based on at least one transmission rate measured at least one previous time.

10. A method for data processing including encoding and sending, comprising:

encoding data using a selected one of a plurality of encoding parameter sets:

sending the encoded data to a receiver via a communication network;

identifying an original data set for which the data processing is to be initiated at a start time t 0 , and identifying a deadline time t L by which the data processing is to be completed, wherein the original data set is one data sub-set or a sequence of two or more data sub-sets;

calculating a length of an assigned time not exceeding a time limit (=t L −t 0 ) for the original data set, per each data sub-set;

calculating an estimate of an individual processing time T P to encode and send each data sub-set using a successively-selected one of the plurality of encoding parameter sets, per each data sub-set, based on the assigned time for the each data sub-set, an estimate of an encoding time T E to encode the each data sub-set using the successively-selected one encoding parameter set, and an estimate of a sending time T T to send the encoded data sub-set at a transmission rate; and

selecting one of the plurality of encoding parameter sets to allow a total processing time to fall within a shortened time limit (=α·t L −t 0 , 0<α<1) that is equal to the time limit (=t 1 −t 0 ) minus a marginal time,

wherein the total processing time, if the original data set is one data sub-set, is equal to the individual processing time for the one data sub-set, or if the original data set includes a sequence of two or more data sub-sets, is equal to a total of the individual processing times for the two or more data sub-sets.

11. A computer-readable non-transitory recording media having stored therein a program, when executed by a computer, to implement the method according to claim 10 .

12. A method for data processing including encoding and sending, comprising:

encoding original data using a selected one of a plurality of encoding parameter sets;

sending the encoded data to a receiver via a communication network;

calculating a time limit (=t L −t 0 ) for the data processing of the original data, from a start time t 0 at which the data processing is to be initiated, and a deadline time t L by which the data processing is to be completed;

calculating an estimate of a processing time to encode and send the original data using a successively-selected one of the plurality of encoding parameter sets, based on an estimate of an encoding time to encode the original data using the successively-selected one encoding parameter set, and an estimate of a sending time to send the encoded data at a transmission; and

selecting one of the plurality of encoding parameter sets to allow the estimate of the processing time to fall within a shortened time limit (=α·t L −t 0 , 0<α<1) that is equal to the time limit (=t L −t 0 ) minus a marginal time.