An apparatus to determine an encoding mode to encode an audio signal, comprising:nat least one processor; anda determining unit to generate a short-term feature and a long-term feature for a current frame, to generate a parameter by using the long-term feature, to adaptively adjust a mode determination threshold of the short-term feature in a unit of frames by using the parameter and to determine one of an audio encoding mode and a music encoding mode of the current frame based on a comparison of the short-term feature and the adjusted mode determination threshold so that the current frame of the audio signal is encoded according to the determined encoding mode.
›2.↳ 1The apparatus of claim 1, further comprising:na time-domain coding unit to encode the audio signal according to the encoding mode in a time-domain; an…d2
The apparatus of claim 1, further comprising:na time-domain coding unit to encode the audio signal according to the encoding mode in a time-domain; anda frequency-domain coding unit to encode the audio signal according to the encoding mode in a frequency-domain.
›3.↳ 1The apparatus of claim 1, further comprising:na speech coding unit to encode the audio signal as a speech signal according to the encoding mode; anda …d2
The apparatus of claim 1, further comprising:na speech coding unit to encode the audio signal as a speech signal according to the encoding mode; anda music coding unit to encode the audio signal as a music signal according to the encoding mode.
›4.↳ 1The apparatus of claim 1, further comprising:na speech coding unit to receive the audio signal and the encoding mode from the determining unit to enco…d2
The apparatus of claim 1, further comprising:na speech coding unit to receive the audio signal and the encoding mode from the determining unit to encode the audio signal when the encoding mode is the speech encoding mode; anda music coding unit to receive the audio signal and the encoding mode from the determining unit to encode the audio signal when the encoding mode is music encoding mode.
›5.↳ 1The apparatus of claim 1, further comprising:na coding unit to encode the audio signal according to the encoding mode; anda bitstream generation unit …d2
The apparatus of claim 1, further comprising:na coding unit to encode the audio signal according to the encoding mode; anda bitstream generation unit to generate a bitstream according to the encoded audio signal and information on the encoding mode.
›6.↳ 1The apparatus of claim 1, wherein the determining unit comprises:na short term feature generation unit to generate the short-term feature from the cur…d2+5
The apparatus of claim 1, wherein the determining unit comprises:na short term feature generation unit to generate the short-term feature from the current frame of the audio signal; anda long-term feature generation unit to generate the long-term feature from the current frame and at least one previous frame.
›7.↳ 6The apparatus of claim 6, wherein the determining unit further comprises:na mode determination threshold adjustment unit to adjust the mode determinat…d3
The apparatus of claim 6, wherein the determining unit further comprises:na mode determination threshold adjustment unit to adjust the mode determination threshold using the short term feature and the long-term feature; andan encoding determination unit to determine the encoding mode according to the adjusted mode determination threshold and the short-term feature.
›8.↳ 6The apparatus of claim 6, wherein the mode determination threshold adjustment unit adjusts the mode determination threshold using the short term featu…d3
The apparatus of claim 6, wherein the mode determination threshold adjustment unit adjusts the mode determination threshold using the short term feature, the long-term feature, and an encoding mode of the at least one the previous frame.
›9.↳ 6The apparatus of claim 6, wherein the encoding determination unit determines the encoding mode according to the adjusted mode determination threshold,…d3
The apparatus of claim 6, wherein the encoding determination unit determines the encoding mode according to the adjusted mode determination threshold, the short-term feature, and an encoding mode of the at least one previous frame.
›10.↳ 6The apparatus of claim 6, wherein the long-term feature generation unit comprises:na first long-term feature generation unit to generate a first long-…d3+1
The apparatus of claim 6, wherein the long-term feature generation unit comprises:na first long-term feature generation unit to generate a first long-term feature according to the short-term feature of the current frame and a short-term feature of the at least one previous frame; anda second long-term feature generation unit to generate a second long-term feature as the long-term feature according to the first long-term feature and a variation feature of at least one of the current frame and the at least one previous frame.
›11.↳ 10The apparatus of claim 10, wherein the determining unit further comprises:na mode determination threshold adjustment unit to adjust a mode determinati…d4
The apparatus of claim 10, wherein the determining unit further comprises:na mode determination threshold adjustment unit to adjust a mode determination threshold according to the short term feature and the second long-term feature; andan encoding determination unit to determine the encoding mode according to the adjusted mode determination threshold and the short-term feature.
›12.↳ 1The apparatus of claim 1, wherein the determining unit determines the encoding mode of the first frame of the audio signal according to the short-term…d2
The apparatus of claim 1, wherein the determining unit determines the encoding mode of the first frame of the audio signal according to the short-term feature, the long-term feature, and an encoding mode of a previous frame.
›13.↳ 1The apparatus of claim 1, wherein the determining unit comprises:nan LP-LTP gain generation unit to generate an LP-LTP gain as the short-term feature …d2
The apparatus of claim 1, wherein the determining unit comprises:nan LP-LTP gain generation unit to generate an LP-LTP gain as the short-term feature of the current frame; anda long-term feature generation unit to generate the long-term feature according to the LP-LTP gain of the current frame and a second LP-LTP gain of at least one previous frames.
›14.↳ 1The apparatus of claim 1, wherein the determining unit comprises:na spectrum tilt generation unit to generate a spectrum tilt as the short-term featur…d2
The apparatus of claim 1, wherein the determining unit comprises:na spectrum tilt generation unit to generate a spectrum tilt as the short-term feature of the current frame; anda long-term feature generation unit to generate the long-term feature according to the spectrum tilt of the current frame and a second spectrum tilt of at least one previous frames.
›15.↳ 1The apparatus of claim 1, wherein the determining unit comprises:na zero crossing rate generation unit to generate a zero crossing rate as the short-t…d2
The apparatus of claim 1, wherein the determining unit comprises:na zero crossing rate generation unit to generate a zero crossing rate as the short-term feature of the current frame; anda long-term feature generation unit to generate the long-term feature according to the zero crossing rate of the current frame and a second zero crossing rate of at least one previous frames.
›16.↳ 1The apparatus of claim 1, wherein the determining unit comprises:na short-term feature generation unit having one or a combination of an LP-LTP gain g…d2
The apparatus of claim 1, wherein the determining unit comprises:na short-term feature generation unit having one or a combination of an LP-LTP gain generation unit to generate an LP-LTP gain as the short-term feature of the current frame, a spectrum tilt generation unit to generate a spectrum tilt as the short-term feature of the current frame, and a zero crossing rate generation unit to generate a zero crossing rate as the short-term feature of the current frame; anda long-term feature generation unit to generate the long-term feature according to the short-term feature of the current frame and a second short-term feature of at least one frame.
›17.↳ 1The apparatus of claim 1, wherein the determination unit comprises a memory to store the short-term and long-term features of the current frame and pr…d2
The apparatus of claim 1, wherein the determination unit comprises a memory to store the short-term and long-term features of the current frame and previous frames.
›18.↳ 1The apparatus of claim 1, wherein:nthe long-term feature is determined according to the short-term feature of the current frame and short-term feature…d2
The apparatus of claim 1, wherein:nthe long-term feature is determined according to the short-term feature of the current frame and short-term features of a plurality of previous frames.
›19.↳ 1The apparatus of claim 1, wherein:nthe long-term feature is determined according to a variation feature between the current frame and a previous frame…d2
The apparatus of claim 1, wherein:nthe long-term feature is determined according to a variation feature between the current frame and a previous frame.
›20.↳ 1The apparatus of claim 1, wherein:nthe long-term feature is determined according to a variation feature of a second encoding mode of the previous fram…d2
The apparatus of claim 1, wherein:nthe long-term feature is determined according to a variation feature of a second encoding mode of the previous frame.
