WO2007097550A1 - Method and apparatus for processing an audio signal - Google Patents
Method and apparatus for processing an audio signal Download PDFInfo
- Publication number
- WO2007097550A1 WO2007097550A1 PCT/KR2007/000866 KR2007000866W WO2007097550A1 WO 2007097550 A1 WO2007097550 A1 WO 2007097550A1 KR 2007000866 W KR2007000866 W KR 2007000866W WO 2007097550 A1 WO2007097550 A1 WO 2007097550A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- signal
- extension
- ancillary
- information
- decoding
- Prior art date
Links
- 230000005236 sound signal Effects 0.000 title claims abstract description 106
- 238000000034 method Methods 0.000 title claims abstract description 44
- 230000003044 adaptive effect Effects 0.000 claims description 5
- 238000010586 diagram Methods 0.000 description 16
- 241001269238 Data Species 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 230000002123 temporal effect Effects 0.000 description 2
- 238000009499 grossing Methods 0.000 description 1
- 238000013139 quantization Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10L—SPEECH ANALYSIS TECHNIQUES OR SPEECH SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING TECHNIQUES; SPEECH OR AUDIO CODING OR DECODING
- G10L19/00—Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis
- G10L19/04—Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis using predictive techniques
- G10L19/16—Vocoder architecture
- G10L19/167—Audio streaming, i.e. formatting and decoding of an encoded audio signal representation into a data stream for transmission or storage purposes
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10L—SPEECH ANALYSIS TECHNIQUES OR SPEECH SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING TECHNIQUES; SPEECH OR AUDIO CODING OR DECODING
- G10L19/00—Speech or audio signals analysis-synthesis techniques for redundancy reduction, e.g. in vocoders; Coding or decoding of speech or audio signals, using source filter models or psychoacoustic analysis
- G10L19/008—Multichannel audio signal coding or decoding using interchannel correlation to reduce redundancy, e.g. joint-stereo, intensity-coding or matrixing
Definitions
- the present invention relates to a method and apparatus for processing an audio signal.
- the present invention is suitable for a wide scope of applications, it is particularly suitable for processing a residual signal.
- an audio signal includes a downmix signal and an ancillary data signal.
- the ancillary data signal can include a spatial information signal and an extension signal.
- the extension signal means an additional signal necessary to enable a signal to be reconstructed close to an original signal in generating a multi-channel signal by upmixing the downmix signal.
- the extension signal can include a residual signal.
- the residual signal means a signal corresponding to a difference between an original signal and a coded signal.
- the residual signal is usable for the following cases. For instance, the residual signal is usable for compensation of an artistic downmix signal or specific channel compensation in decoding. And, the residual signal is usable for both of the compensations as well. So, it is able to reconstruct an inputted audio signal into a signal closer to an original signal using the residual signal to enhance sound quality.
- header information for an audio signal is not variable in general, the header information is inserted in a bit stream once only. But in case that the header information is inserted in the bit stream once only, if an audio signal needs to be decoded from a random timing point for broadcasting or VOD, it may be unable to decode data frame information due to the absence of the header information.
- the present invention is directed to a method and apparatus for processing an audio signal that substantially obviate one or more of the problems due to limitations and disadvantages of the related art.
- An object of the present invention is to provide a method and apparatus for processing an audio signal, by which a processing efficiency of the audio signal is enhanced by skipping decoding of an extension signal.
- a further object of the present invention is to provide a method and apparatus for processing an audio signal, by which the audio signal is processed according to level information.
- the present invention selectively decodes an extension signal to enable more efficient decoding.
- the present invention is able to enhance a sound quality of an audio signal.
- the present invention is able to reduce complexity.
- the present invention is able to enhance a sound quality by decoding a predetermined low frequency part only and also reduce a load of operation.
- the present invention is able to process an audio signal from a random timing point in a manner of identifying a presence or non- presence of header information within the audio signal.
- FIG. 1 is a block diagram of an audio signal encoding apparatus and an audio signal decoding apparatus according to an embodiment of the present invention
- FIG. 2 is a schematic block diagram of an extension signal decoding unit 90 according to an embodiment of the present invention
- FIG. 3 and FIG. 4 are diagrams to explain fixed bits assignment of length information for an extension signal according to an embodiment of the present invention.
- FIG. 5 and FIG. 6 are diagrams to explain variable bits assignment of length information for an extension signal by depending on a length type according to an embodiment of the present invention
- FIG. 7 and FIG. 8 are diagrams to explain adaptive bits assignment of length information for an extension signal by depending on a real length of the extension signal according to an embodiment of the present invention
- FIG. 9 is a diagram of a bit stream structure configuring an audio signal with a downmix signal, an ancillary signal, and an extension signal according to an embodiment of the present invention
- FIG. 10 is a diagram of a bit stream structure configuring an audio signal with an ancillary signal including an extension signal and a downmix signal according to an embodiment of the present invention
- FIG. 11 is a diagram of a bit stream structure configuring an independent audio signal with a downmix signal or an ancillary signal according to an embodiment of the present invention
- FIG. 12 is a diagram of a broadcasting streaming structure configuring an audio signal with a downmix signal and an ancillary signal according to an embodiment of the present invention
- FIG. 13 is a flowchart of a method of processing an extension signal using length information of the extension signal in accordance with identification information indicating whether a header is included within an ancillary signal in case if using an audio signal for broadcasting or the like according to an embodiment of the present invention.
- FIG. 14 is a flowchart of a method of decoding an extension signal selectively using length information of the extension signal in accordance with a level of a bit stream according to an embodiment of the present invention.
- a method for processing an audio signal includes the steps of extracting an ancillary signal for generating the audio signal and an extension signal included in the ancillary signal from a received bit stream, reading length information of the extension signal, skipping decoding of the extension signal or not using a result of the decoding based on the length information, and generating the audio signal using the ancillary signal.
- a method for processing an audio signal includes the steps of acquiring sync information indicating a location of an ancillary signal for generating the audio signal and a location of an extension signal included in the ancillary signal, skipping decoding of the extension signal or not using a result of the decoding based on the sync information, and generating the audio signal using the ancillary signal.
- an apparatus for processing an audio signal includes a signal extracting unit extracting an ancillary signal for generating the audio signal and an extension signal included in the ancillary signal from a received bit stream, an extension signal length reading unit reading length information of the extension signal, a selective decoding unit skipping decoding of the extension signal or not using a result of the decoding based on the length information, and an upmixing unit generating the audio signal using the ancillary signal.
- an apparatus for processing an audio signal includes a sync information acquiring unit acquiring sync information indicating a location of an ancillary signal for generating the audio signal and a location of an extension signal included in the ancillary signal, a selective decoding unit skipping decoding of the extension signal or not using a result of the decoding based on the sync information, and an upmixing unit generating the audio signal using the ancillary signal.
- FIG. 1 is a block diagram of an audio signal encoding apparatus and an audio signal decoding apparatus according to an embodiment of the present invention.
- an encoding apparatus includes a downmixing unit 10, a downmix signal encoding unit 20, an ancillary signal encoding unit 30, an extension signal encoding unit 40, and a multiplexing unit 50.
- the downmixing unit 10 In case that multi-source audio signals Xl, X2, ..., Xn are inputted to the downmixing unit 10, the downmixing unit 10 generates a downmix signal by downmixing the multi- source audio signals.
- the downmix signal includes a mono signal, a stereo signal, or a multi-source audio signal.
- the source includes a channel and is described as the channel for convenience. In the specification of the present invention, explanation is made with reference to a mono or stereo downmix signal. Yet, the present invention is not limited to the mono or stereo downmix signal.
- the encoding apparatus is able to use an artistic downmix signal provided from an outside selectively and directly.
- an ancillary signal can be generated from a multi-channel audio signal and an extension signal corresponding to additional information can be generated as well.
- the ancillary signal can include a spatial information signal and an extension signal.
- the generated downmix, ancillary and extension signals are encoded by the downmix signal encoding unit 20, the ancillary signal encoding unit 30, and the extension signal encoding unit 40 and are then transferred to the multiplexing unit 50, respectively.
- the ⁇ spatial information' means the information necessary for the encoding apparatus to transfer a downmix signal generated from downmixing multi-channel signals to the decoding apparatus and necessary for the decoding apparatus to generate multichannel signals by upmixing the downmix signal.
- the spatial information includes spatial parameters.
- the spatial parameters include CLD (channel level difference) indicating an energy difference between channels, ICC (inter-channel coherences) meaning a correlation between channels, CPC (channel prediction coefficients) used in generating three channels from two channels, etc.
- the 'extension signal' means additional information necessary to enable a signal to be reconstructed closer to an original signal in generating multi-channel signals by upmixing the downmix signal by the decoding apparatus.
- the additional information includes a residual signal, an artistic downmix residual signal, an artistic tree extension signal, etc.
- the residual signal indicates a signal corresponding to a difference between an original signal and an encoded signal.
- the residual signal includes a general residual signal or an artistic downmix residual signal for compensation of an artistic downmix signal.
- the downmix signal encoding unit 20 or the downmix signal decoding unit 70 means a codec that encodes or decodes an audio signal not included with an ancillary signal.
- a downmix audio signal is taken as an example of not included with the ancillary signal the audio signal.
- the downmix signal encoding unit 20 or the downmix signal decoding unit 70 is able to include MP3, AC-3, DTS, or AAC. If a codec function is performed on an audio signal, the downmix signal encoding unit 20 and the downmix signal decoding unit 70 can include a codec to be developed in the future as well as a previously developed codec.
- the multiplexing unit 50 can generate a bit stream by multiplexing a downmix signal, an ancillary signal, and an extension signal and then transfer the generated bit stream to the decoding apparatus.
- both of the downmix signal and the ancillary signal can be transferred in a bit stream format to the decoding apparatus.
- the ancillary signal and the downmix signal can be transferred in independent bit stream formats to the decoding apparatus, respectively. Details of the bit streams are explained in FIGs. 9 to 11. In case that it is unable to use previously transferred header information since an audio signal starts to be decoded from a random timing point instead of being decoded from the beginning like a bit stream for broadcasting, it is able to decode the audio signal using another header information inserted in the audio signal.
- header information can be inserted in an audio signal at least once. If header information exists in a front part of an audio signal only once, it is unable to perform decoding due to the absence of the header information in case of receiving an audio signal at a random timing point.
- header information can be included according to a preset format (e.g., temporal interval, spatial interval, etc.). It is able to insert identification information indicating a presence or non-presence of header information in a bit stream. And, an audio signal is able to selectively include a header according to the identification information.
- the decoding apparatus includes a demultiplexing unit 60, a downmix signal decoding unit 70, an ancillary signal decoding unit 80, an extension signal decoding unit 90, and an upmixing unit 100.
- the demultiplexing unit 60 receives a bit stream and then separates an encoded downmix signal, an encoded ancillary signal, and an encoded extension signal from the received bit stream.
- the downmix signal decoding unit 70 decodes the encoded downmix signal.
- the ancillary signal decoding unit 80 decodes the encoded ancillary signal .
- the extension signal can be included in the ancillary signal. It is necessary to efficiently decode the extension signal to efficiently generate multi-channel audio signals. So, the extension signal decoding unit 90 is able to selectively decode the encoded extension signal. In particular, the encoded extension signal can be decoded or the decoding of the encoded extension signal can be skipped. Occasionally, if the decoding of the extension signal is skipped, the encoded signal can be reconstructed to be closer to an original signal and coding efficiency can be raised.
- the decoding apparatus For instance, if a level of the decoding apparatus is lower than that of a bit stream, the decoding apparatus is unable to decode the received extension signal. So, the decoding of the extension signal can be skipped. Even if the decoding of the extension signal is available because the level of the decoding apparatus is higher than that of the bit stream, the decoding of the extension signal is able to be skipped by another information obtained from the audio signal. In this case, for instance, the another information may include information indicating whether to execute the decoding of the extension signal. This is explained in detail with reference to FIG. 14 later.
- length information of the extension signal is read from the bit stream and the decoding of the extension signal is able to be skipped using the length information.
- it is able to skip the decoding of the extension signal using sync information indicating a position of the extension signal. This is explained in detail with reference to FIG. 2 later.
- the length information of the extension signal can be defined in various ways. For instance, fixed bits can be assigned, or variable bits can be assigned according to a predetermined length information type, or bits suitable for a length of a real extension signal can be adaptively assigned while the length of the extension signal is read. Details of the fixed bits assignment are explained in FIG.
- the length information of the extension signal can be located within an ancillary data area.
- the ancillary data area indicates an area where additional information necessary to reconstruct a downmix signal into an original signal exists.
- a spatial information signal or an extension signal can be taken as an example of the ancillary data.
- the length information of the extension signal can be located within the ancillary signal or an extension area of the ancillary signal .
- the length information of the extension signal is located within a header extension area of the ancillary signal, a frame data extension area of the ancillary signal, or both of the header extension area and the frame data extension area of the ancillary signal.
- FIG. 2 is a schematic block diagram of an extension signal decoding unit 90 according to an embodiment of the present invention.
- the extension signal decoding unit 90 includes an extension signal type information acquiring unit 91, an extension signal length reading unit 92, and a selective decoding unit 93.
- the selective decoding unit 93 includes a level deciding unit 94, an extension signal information acquiring unit 95, and an extension signal information skipping unit 96.
- the extension signal decoding unit 90 receives a bit stream for an extension signal from the demultiplexing unit 60 and then outputs a decoded extension signal. Occasionally, the extension signal decoding unit 90 may not output an extension signal or can output an extension signal by padding a bit stream for the extension signal with zeros completely.
- the extension signal type acquiring unit 91 acquires information indicating a type of an extension signal from a bit stream.
- the information indicating the type of the extension signal can include a residual signal, an artistic downmix residual signal, an artistic tree extension signal, or the like.
- the residual signal is a generic term of a general residual signal or an artistic downmix residual signal for compensation of an artistic downmix signal.
- the residual signal is usable for compensation of an artistic downmix signal in multi-channel audio signals or specific channel compensation in decoding.
- the two cases are usable as well.
- the extension signal length reading unit 92 reads a length of the extension signal decided by the type information of the extension signal. This can be achieved regardless of whether to perform the decoding of the extension signal.
- the selective decoding unit 93 selectively performs decoding on the extension signal. This can be decided by the level deciding unit 94. In particular, the level deciding unit 94 selects whether to execute the decoding of the extension signal by comparing a level of a bit stream to a level of a decoding apparatus.
- the decoding apparatus acquires information for the extension signal via the extension signal information acquiring unit 95 and then decodes the information to output the extension signal.
- the outputted extension signal is transferred to an upmixing unit 100 to be used in reconstruct an original signal or generating an audio signal.
- the level of the decoding apparatus is lower than that of the bit stream, it is able to skip the decoding of the extension signal via the extension signal information skipping unit 96. In this case, it is able to skip the decoding of the extension signal based on the length information read by the extension signal length reading unit 92.
- the reconstruction can be achieved to get closer to the original signal to enhance a sound quality. If necessary, it is able to reduce a load of operation of the decoding apparatus by omitting the decoding of the extension signal.
- bit or byte length information of the extension signal can be inserted in data. And, the decoding can keep proceeding by skipping a bit field of the extension signal as many as a value obtained from the length information.
- the method of omitting the decoding of the extension signal it is able to skip the decoding of the extension signal based on sync information indicating a position of the extension signal. For instance, it is able to insert a sync word having predetermined bits in the point where the extension signal ends.
- the decoding apparatus keeps searching the bit field of the residual signal until finding a sync word of the extension signal. Once finding the sync word, the decoding apparatus stops the search process and then keeps performing the decoding. In particular, it is able to skip the decoding of the extension signal until the sync word of the extension signal is found.
- a decoding method in case of performing the decoding of the extension signal, it is able to perform the decoding after parsing the extension signal.
- the sync word of the extension signal is read but may not be available.
- FIG. 3 and FIG. 4 are diagrams to explain fixed bits assignment of length information for an extension signal according to an embodiment of the present invention.
- the length information of the extension signal can be defined by a bit or byte unit. If the length information is decided by the byte unit, this means that the extension signal is assigned bytes.
- FIG. 3 shows a method of defining length information for an extension signal in a simplest way.
- FIG. 4 shows the method shown in FIG. 3 schematically.
- a syntax element for indicating the length information of the extension signal is defined and predetermined bits are assigned to the syntax element. For instance, ⁇ bsResidualSignalLength' is defined as the syntax element and 16 bits are assigned as fixed bits. Yet, this method may consume a relatively considerable amount of bits, So, the methods shown in FIG. 5, FIG. 6, FIG. 7, and FIG. 8 are explained as follows.
- FIG. 5 and FIG. 6 are diagrams to explain variable bits assignment of length information for an extension signal by depending on a length type according to an embodiment of the present invention.
- FIG. 5 shows a method of defining one more syntax element for defining how many bits are used for
- FIG. 6 schematically illustrates the method shown in
- ⁇ bsResidualSignalLengthtype' is newly defined as a length type. If a value of the ⁇ bsResidualSignalLengthtype' is zero, four bits are assigned to the ⁇ bsResidualSignalLength' . If a value of the ⁇ bsResidualSignalLengthtype' is 1, eight bits are assigned to the ⁇ bsResidualSignalLength' . If a value of the ⁇ bsResidualSignalLengthtype' is 2, twelve bits are assigned to the ⁇ bsResidualSignalLength' .
- ⁇ bsResidualSignalLengthtype' 3 bits are assigned to the ⁇ bsResidualSignalLength' .
- the assigned bits are exemplary. So, bits different from the above-defined bits can be assigned. To reduce the bit consumption more than those of the above methods, the method shown in FIG. 7 and FIG. 8 is provided.
- FIG. 7 and FIG. 8 are diagrams to explain adaptive bits assignment of length information for an extension signal by depending on a real length of the extension signal according to an embodiment of the present invention.
- a length information value of the extension signal can be read up to an initially determined value. If the length information value equals to a predetermined value, it is able to read additionally up to a further determined value. If the length information value equals to another predetermined value, it is able to read additionally up to another further determined value. In this case, if the length information value is not another predetermined value, the corresponding value is outputted as the length information value as it is.
- the length information of the extension signal is adaptively read according to a real data length, whereby the bit consumption can be maximally reduced. The example shown in FIG. 7 or FIG. 8 is explained.
- FIG.8 schematically illustrates another example of the adaptive bits assignment of length information for an extension signal.
- the length information of the extension signal can be length information of the extension signal header or length information of the extension signal frame data. So, the length information of the extension signal can be located in a header area and/or a frame data area. Bit stream structures for this are explained with reference to FIGs. 9 to 12.
- FIG. 9 and FIG. 10 show embodiments of the present invention, in which a bit stream structure configuring an audio signal with a downmix signal, an ancillary signal, and an extension signal is shown.
- An audio signal includes a downmix signal and an ancillary signal.
- a spatial information signal can be taken.
- Each of the downmix signal and the ancillary signal is transferred by a frame unit.
- the ancillary signal can include header information and data information or can include data information only.
- the header information precedes and is followed by the data information.
- a downmix signal header and an ancillary signal header can exist as the header information in a front part.
- downmix signal data and ancillary signal data can configure one frame as the data information behind the front part.
- an extension signal can be included within the ancillary signal or can be used as an independent signal.
- FIG. 9 shows a case that the extension signal is used as the independent signal
- FIG. 10 shows a case that the extension signal is located in the extension area within the ancillary signal.
- an extension signal header can exist as header information in the front part as well as the downmix header and the spatial information header.
- extension signal data can be further included as data information as well as the downmix signal data and the ancillary signal data to configure one frame.
- extension signal can be selectively decoded, it can be located at a last part of the frame or can consecutively exist right behind the ancillary signal.
- the length information explained in FIGs. 3 to 8 can exist within the header area of the extension signal and/or the data area of the extension signal.
- the length information existing within the header area (extension signal header) indicates the length information of the extension signal header
- the length information existing within the data area (extension signal data) indicates the length information of the extension signal data.
- the length information existing each of the areas is read from a bit stream and the decoding apparatus is able to skip the decoding of the extension signal based on the length information.
- FIG. 11 is a diagram of a bit stream structure configuring an independent audio signal with a downmix signal or an ancillary signal according to an embodiment of the present invention.
- An audio signal includes a downmix signal and an ancillary signal.
- a spatial information signal can be taken.
- the downmix signal and the ancillary signal can be transferred as independent signals, respectively.
- the downmix signal has a structure that a downmix signal header (downmix signal header®) as header information is located at a front part and that downmix signal datas (downmix signal data ⁇ , ⁇ , ® , ..., ⁇ ) as data information follow the downmix signal header.
- the ancillary signal has a structure that an ancillary signal header (ancillary signal header ®) as header information is located at a front part and that
- ancillary signal datas (ancillary signal data ⁇ , ⁇ , ..., ⁇ ) as data information follow the ancillary signal header. Since the extension signal can be included within the ancillary signal, a structure that the extension signal follows the ancillary signal data can be provided. So, an extension signal header ® follows the ancillary signal header ® and the extension signal data ⁇ follows the ancillary signal data ® . Likewise, the extension signal data ⁇ follows the ancillary signal data ⁇ . In this case, length information of the extension signal can be included
- each of the extension signal header ⁇ , the extension signal data ⁇ , and/or the extension signal data ⁇ , ..., and ⁇ is included in each of the extension signal header ⁇ , the extension signal data ⁇ , and/or the extension signal data ⁇ , ..., and ⁇ .
- FIG. 12 is a diagram of a broadcasting streaming structure configuring an audio signal with a downmix signal and an ancillary signal according to an embodiment of the present invention.
- the header information can be inserted in the audio signal once at least.
- the header information can be included according to a preset format (e.g., temporal interval, spatial interval, etc.) .
- the header information can be inserted in each frame, periodically inserted in each frame with a fixed interval, or non-periodically inserted in each frame with a random interval.
- the header information can be inserted once according to a fixed time interval (e.g., 2 seconds).
- a broadcast streaming structure configuring one audio signal has a structure that at least once header information is inserted between data informations. For instance, in case of a broadcast streaming structure configuring one audio signal, a downmix signal comes first and an ancillary signal follows the downmix signal. Sync information for distinguishing between the downmix signal and the ancillary signal can be located at a front part of the ancillary signal. And, identification information indicating whether header information for the ancillary signal exists can be located. For instance, if header identification information is 0, a next read frame only has a data frame without header information. If the header identification information is 1, a next read frame has both header information and a data frame. This is applicable to the ancillary signal or the extension signal.
- header informations may be the same of the header information having been initially transferred or can be variable.
- header information is variable, new header information is decoded and data information transferred after the new header information is then decoded according to the decoded new header information.
- the header identification information is 0, a transferred frame only has a data frame without header information. In this case, to process the data frame, previously transferred header information can be used. For instance, if the header identification information is 1 in FIG. 12, an ancillary
- extension signal header ® and an extension signal header ⁇ can exist. Yet, if a next incoming frame has no header information since the header identification information set to 0, it is able to use information of the extension signal header ⁇ previously transferred to process extension signal data ⁇ .
- FIG. 13 is a flowchart of a method of processing an extension signal based on length information of the extension signal in accordance with identification information indicating whether a header is included within an ancillary signal in case of using an audio signal for broadcasting or the like according to an embodiment of the present invention.
- an ancillary signal for an audio signal generation and an extension signal included in the ancillary signal are extracted from a received bit stream (1301).
- the extension signal can be included within the ancillary signal.
- Identification information indicating whether a header is included in the ancillary signal is extracted (1303). For instance, if the header identification information is 1, it indicates that an ancillary signal header is included in the ancillary signal. If the header identification information is 0, it indicates that an ancillary signal header is not included in the ancillary signal. In case that the extension signal is included in the ancillary signal, if the header identification information is 1, it indicates that an extension signal header is included in the extension signal.
- the header identification information is 0, it indicates that an extension signal header is not included in the extension signal. It is decided that whether a header is included in the ancillary signal according to the header identification information (1305). If the header is included in the ancillary signal, length information is extracted from the header (1307) . And, it is able to skip decoding of the extension signal based on the length information (1309). In this case, the header plays a role in enabling each ancillary signal and/or each extension signal to be interpreted.
- the header information can include information for a residual signal, length information for a residual signal, sync information indicating a location of a residual signal, a sampling frequency, a frame length, the number of a parameter band, tree information, quantization mode information, ICC
- the header is not included in the ancillary signal according to the header identification information, it is able to skip decoding of the extension signal based on the previously extracted length information for the header (1311) .
- FIG. 14 is a flowchart of a method of decoding an extension signal selectively based on length information of the extension signal according to an embodiment of the present invention.
- a profile means that technical elements for algorithm in a coding process are standardized.
- the profile is a set of technical elements necessary to decode a bit stream and corresponds to a sort of a sub-standard.
- a level defines a range of the technical elements, which are prescribed in the profile, to be supported.
- the level plays a role in defining capability of a decoding apparatus and complexity of a bit stream.
- level information can include definitions for the profile and level.
- a decoding method of an extension signal can selectively vary according to the level information of the bit stream and the level information of the decoding apparatus. For instance, even if the extension signal exists in a transferred audio signal, decoding of the extension signal may be or may not be executed as a result of deciding the level information.
- the decoding is executed, a predetermined low frequency part can be used only. Besides, it is able to skip the decoding of the extension signal as many as length information of the extension signal in order not to execute the decoding of the extension signal.
- the extension signal is entirely read, the decoding cannot be executed. Furthermore, a portion of the extension signal is read, decoding can be performed on the read portion only, and the decoding cannot be performed on the rest of the extension signal. Alternatively, the extension signal is entirely read, a portion of the extension signal can be decoded, and the rest of the extension signal cannot be decoded.
- an ancillary signal for generating an audio signal and an extension signal included in the ancillary signal can be extracted from a received bit stream (1410) .
- information for the extension signal can be extracted.
- the information for the extension signal may include extension data type information indicating a data type of the extension signal.
- the extension data type information includes residual coding data, artistic downmix residual coding data, artistic tree extension data, or the like. So, the type of the extension signal is decided and it is able to read length information of the extension signal from an extension area of the audio signal (1420) . Subsequently, a level of the bit stream is decided. This can be decided with reference to following information.
- the level information for the bit stream can include the number of output channels, a sampling rate, a bandwidth of a residual signal, and the like. So, if the above-explained level informations of the bit stream are inputted, they are compared to level information for a decoding apparatus to decide whether the extension signal will be decoded (1430) . In this case, a level of the decoding apparatus can be previously set. In general, the level of the decoding apparatus should be equal to or greater than a level of the audio signal. This is because the decoding apparatus should be able to decode the transferred audio signal entirely.
- decoding is occasionally possible. Yet, a corresponding quality may be degraded. For instance, if the level of the decoding apparatus is lower than that of the audio signal, the decoding apparatus may be unable to decode the audio signal. Yet, in some cases, the audio signal can be decoded based on the level of the decoding apparatus .
- the level of the decoding apparatus In case that the level of the decoding apparatus is decided lower than that of the bit stream, it is able to skip the decoding of the extension signal based on the length information of the extension signal (1440). On the other hand, in case that the level of the decoding apparatus is equal to or higher than that of the bit stream, it is able to execute the decoding of the extension signal (1460). Yet, although the decoding of the extension signal is executed, the decoding can be performed on a predetermined low frequency portion of the extension signal only (1450).
- the decoding apparatus is a low power decoder, if the extension signal is entirely decoded, efficiency is degraded, or since the decoding apparatus is unable to decode the entire extension signal a predetermined low frequency portion of the extension signal is usable. And, this is possible if the level of the bit stream or the level of the decoding apparatus meets a prescribed condition only.
- the signals include audio signals and/or video signals.
Landscapes
- Engineering & Computer Science (AREA)
- Computational Linguistics (AREA)
- Signal Processing (AREA)
- Health & Medical Sciences (AREA)
- Audiology, Speech & Language Pathology (AREA)
- Human Computer Interaction (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Compression, Expansion, Code Conversion, And Decoders (AREA)
- Compression Or Coding Systems Of Tv Signals (AREA)
- Two-Way Televisions, Distribution Of Moving Picture Or The Like (AREA)
Abstract
Description
Claims
Priority Applications (10)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2008556239A JP5390197B2 (en) | 2006-02-23 | 2007-02-16 | Audio signal processing method and apparatus |
ES07709015T ES2391116T3 (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
BRPI0706488-8A BRPI0706488A2 (en) | 2006-02-23 | 2007-02-16 | method and apparatus for processing audio signal |
KR1020087021418A KR101276849B1 (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
EP07709015A EP1987595B1 (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
US12/280,309 US7881817B2 (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
AU2007218453A AU2007218453B2 (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
CA2636330A CA2636330C (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
CN200780001517.0A CN101361276B (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
HK09105053.4A HK1127825A1 (en) | 2006-02-23 | 2009-06-05 | Method and apparatus for processing an audio signal |
Applications Claiming Priority (8)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US77577506P | 2006-02-23 | 2006-02-23 | |
US60/775,775 | 2006-02-23 | ||
US79190706P | 2006-04-14 | 2006-04-14 | |
US60/791,907 | 2006-04-14 | ||
US80382506P | 2006-06-02 | 2006-06-02 | |
US60/803,825 | 2006-06-02 | ||
KR1020070013364A KR20070087494A (en) | 2006-02-23 | 2007-02-08 | Method and apparatus for decoding multi-channel audio signal |
KR10-2007-0013364 | 2007-02-08 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2007097550A1 true WO2007097550A1 (en) | 2007-08-30 |
Family
ID=38437559
Family Applications (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/KR2007/000868 WO2007097552A1 (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
PCT/KR2007/000867 WO2007097551A1 (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
PCT/KR2007/000866 WO2007097550A1 (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
Family Applications Before (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/KR2007/000868 WO2007097552A1 (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
PCT/KR2007/000867 WO2007097551A1 (en) | 2006-02-23 | 2007-02-16 | Method and apparatus for processing an audio signal |
Country Status (2)
Country | Link |
---|---|
AU (1) | AU2007218453B2 (en) |
WO (3) | WO2007097552A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2395503A2 (en) * | 2009-02-03 | 2011-12-14 | Samsung Electronics Co., Ltd. | Audio signal encoding and decoding method, and apparatus for same |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPWO2010005050A1 (en) * | 2008-07-11 | 2012-01-05 | 日本電気株式会社 | Signal analysis apparatus, signal control apparatus and method, and program |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH08202397A (en) * | 1995-01-30 | 1996-08-09 | Olympus Optical Co Ltd | Voice decoding device |
US5703584A (en) * | 1994-08-22 | 1997-12-30 | Adaptec, Inc. | Analog data acquisition system |
US20040071445A1 (en) * | 1999-12-23 | 2004-04-15 | Tarnoff Harry L. | Method and apparatus for synchronization of ancillary information in film conversion |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5166685A (en) * | 1990-09-04 | 1992-11-24 | Motorola, Inc. | Automatic selection of external multiplexer channels by an A/D converter integrated circuit |
US6973130B1 (en) * | 2000-04-25 | 2005-12-06 | Wee Susie J | Compressed video signal including information for independently coded regions |
EP1315148A1 (en) | 2001-11-17 | 2003-05-28 | Deutsche Thomson-Brandt Gmbh | Determination of the presence of ancillary data in an audio bitstream |
KR100773539B1 (en) | 2004-07-14 | 2007-11-05 | 삼성전자주식회사 | Multi channel audio data encoding/decoding method and apparatus |
-
2007
- 2007-02-16 AU AU2007218453A patent/AU2007218453B2/en active Active
- 2007-02-16 WO PCT/KR2007/000868 patent/WO2007097552A1/en active Application Filing
- 2007-02-16 WO PCT/KR2007/000867 patent/WO2007097551A1/en active Application Filing
- 2007-02-16 WO PCT/KR2007/000866 patent/WO2007097550A1/en active Application Filing
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5703584A (en) * | 1994-08-22 | 1997-12-30 | Adaptec, Inc. | Analog data acquisition system |
JPH08202397A (en) * | 1995-01-30 | 1996-08-09 | Olympus Optical Co Ltd | Voice decoding device |
US20040071445A1 (en) * | 1999-12-23 | 2004-04-15 | Tarnoff Harry L. | Method and apparatus for synchronization of ancillary information in film conversion |
Non-Patent Citations (1)
Title |
---|
See also references of EP1987595A4 * |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2395503A2 (en) * | 2009-02-03 | 2011-12-14 | Samsung Electronics Co., Ltd. | Audio signal encoding and decoding method, and apparatus for same |
EP2395503A4 (en) * | 2009-02-03 | 2013-10-02 | Samsung Electronics Co Ltd | Audio signal encoding and decoding method, and apparatus for same |
Also Published As
Publication number | Publication date |
---|---|
AU2007218453B2 (en) | 2010-09-02 |
WO2007097551A1 (en) | 2007-08-30 |
WO2007097552A1 (en) | 2007-08-30 |
AU2007218453A1 (en) | 2007-08-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7881817B2 (en) | Method and apparatus for processing an audio signal | |
US8185403B2 (en) | Method and apparatus for encoding and decoding an audio signal | |
US20090164227A1 (en) | Apparatus for Processing Media Signal and Method Thereof | |
AU2007218453B2 (en) | Method and apparatus for processing an audio signal | |
CN101361276B (en) | Method and apparatus for processing an audio signal | |
RU2404507C2 (en) | Audio signal processing method and device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 200780001517.0 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2007218453 Country of ref document: AU |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2325/KOLNP/2008 Country of ref document: IN |
|
ENP | Entry into the national phase |
Ref document number: 2007218453 Country of ref document: AU Date of ref document: 20070216 Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: MX/a/2008/008077 Country of ref document: MX |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2636330 Country of ref document: CA |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2007709015 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2008556239 Country of ref document: JP |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1020087021418 Country of ref document: KR |
|
ENP | Entry into the national phase |
Ref document number: 2008137781 Country of ref document: RU Kind code of ref document: A |
|
WWE | Wipo information: entry into national phase |
Ref document number: 12280309 Country of ref document: US |
|
ENP | Entry into the national phase |
Ref document number: PI0706488 Country of ref document: BR Kind code of ref document: A2 Effective date: 20080710 |