DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Specification
The title of the invention is not descriptive. A new title is required that is clearly indicative of the invention to which the claims are directed.
The following title is suggested: --High Frequency Bandwidth Expansion and Low Frequency Restoration based upon Audio Classification Method, Electronic Device, and Storage Medium--.
Claim Objections
Applicant is advised that should claim 11 be found allowable, claim 20 will be objected to under 37 CFR 1.75 as being a substantial duplicate thereof. When two claims in an application are duplicates or else are so close in content that they both cover the same thing, despite a slight difference in wording, it is proper after allowing one claim to object to the other as being a substantial duplicate of the allowed claim. See MPEP § 608.01(m).
In claims 8 and 17, the variable “f” should be explained in the claim similar to the other variables to order to better establish its meaning in the claim.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 6 and 15 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Regarding Claims 6 and 15, see MPEP 2161.01(I)-
"Similarly, original claims may lack written description when the claims define the invention in functional language specifying a desired result but the specification does not sufficiently describe how the function is performed or the result is achieved. For software, this can occur when the algorithm or steps/procedure for performing the computer function are not explained at all or are not explained in sufficient detail (simply restating the function recited in the claim is not necessarily sufficient). In other words, the algorithm or steps/procedure taken to perform the function must be described with sufficient detail so that one of ordinary skill in the art would understand how the inventor intended the function to be performed. See MPEP §§ 2163.02 and 2181, subsection IV. "
While it is acknowledged that claims 6 and 15 are original claims, per the MPEP citation above, these original claims lack sufficient written description because the specification says nothing about what constitutes the models for low and high band extension/restoration and how they are used based upon coding mode and rate. Accordingly, as the specification fails to disclose what the models comprise and the underlying algorithm for their use in extension restoration, claims 6 and 15 fail to comply with the written description requirement even though they are original claims.
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The independent claims contain antecedent basis issues where it is unclear what term is being referenced due to the lack of a preceding term in each instance. For claim interpretation in the interest of compact prosecution, "the" in each instance will be construed as being replaced by a, an, or deleted based upon proper grammar unless otherwise noted. All dependent claims inherit such antecedent basis issues, and thus, are also indefinite by virtue of their dependency. The lack of antecedent basis issues are as follows:
In Claim 1- "the high-frequency restoration weight and the low-frequency restoration weight" (lines 6-7). Independent claims 10 and 20 contain similar antecedent basis issues and have been similarly rejected under 35 U.S.C. 112(b).
In Claim 5- "a left boundary" (line 12 where term was introduced earlier so it is unclear whether this term should refer back to the earlier instance or represent a new instance, will be construed as --the left boundary--. The same issue is present in lines 14-15. Note that "a value" in each instance was also previous introduced and so should also be corrected to read --the value--. Claim 14 features similar antecedent basis issues, and thus, are found to be indefinite under similar rationale.
Claim Rejections - 35 USC § 101
35 U.S.C. 101 reads as follows:
Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title.
Claims 1-20 are rejected under 35 U.S.C. 101 because the claimed invention is directed to a judicial exception under the broadest reasonable interpretation (BRI) without significantly more.
Independent claims 1, 10, and 20 are rejected under 35 U.S.C. 101 because the claimed invention is directed to an abstract idea without significantly more. The claims regard a process that, as drafted under its broadest reasonable interpretation, covers a mathematical concept with the exception of generic computer components such as a processor and non-transitory computer-readable media.
For example, the method of claim 1 features the steps of classification (mathematical relationships between signal values and class labels- see Paragraphs 0045 and 0048), determining weights (mathematical relationship based upon class- see Paragraph 0073), performing amplitude superposition (mathematical calculation- equation shown in Paragraph 0070), and updating phase (mathematical calculation- equation shown in Paragraph 0074) all of which are described as mathematical calculations in the foregoing specification citations.
This judicial exception is not integrated into a practical application. Outside of the identified abstract idea, the claimed invention only includes generic computer components which amount to no more than mere instructions to implement an otherwise abstract idea using generic computer components. The computer is only used for its ordinary purpose of being used as a tool to execute a program process and is not improved as a tool.
The claim does not include additional elements that are sufficient to amount to significantly more than the judicial exception. The above identified additional generic computer components are no more than mere instructions to apply the exception using generic computer components that are well-known, routine, and conventional as is evidenced by Bancorp Services v. Sun Life (Fed. Cir. 2012) and Alice Corp. v. CLS Bank (2014). Thus, independent claims 1, 10, and 20 are not directed towards patent eligible subject matter under 35 U.S.C. 101.
The following dependent claims do not add patent eligible subject matter because:
Claims 2, 11, and 20- add the process of splitting which relates to signal division based upon a mathematical relationship between parts of a signal and signal characteristics (see Paragraphs 0059-0060) to calculations addressed in the independent claims.
Claims 3-5 and 12-14- narrow weight specifics used in the abstract mathematical calculations.
Claims 6 and 15- add the consideration of data considered in the mathematical algorithm and models that are not defined with any specificity in the specification so as to broadly read upon an abstract table relating weights with different coding rates/modes (Paragraphs 0066-0067).
Claims 7 and 16- narrow the source of the data considered in the mathematical relationship addressed in the independent claims.
Claims 8-9 and 17-18- recite the equations represented in prose in the independent claims.
As a suggestion, Applicant should consider add a step/function of audibly rendering the bandwidth-adjusted signal in order to potentially realize a practical application in step 2A prong 2 and overcome the patent subject matter eligibility rejection under 35 U.S.C. 101.
Claim Rejections - 35 USC § 102
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1, 5, 7, 10, 16, and 19 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Avendano, et al. (U.S. Patent: 9,245,538).
With respect to Claim 1, Avendano discloses:
An audio processing method, comprising:
classifying audio according to contents of the audio (acoustic signal classification based upon the contents of an input acoustic signal (e.g., speech or noise). Col. 7, Lines 10-46; Col. 8, Lines 4-27);
determining a high-frequency restoration weight and a low-frequency restoration weight based on a classification result (Col. 7, Lines 10-17- "uses parameters Params to provide a sophisticated level of control over the bandwidth expansion performed to form bandwidth expanded acoustic signal" wherein the bandwidth expansion process/system involves a "low frequency expansion" with determined weighting (e.g., "gains") based upon classification-based constraints (Col. 8, Lines 44-60 and Col. 9, Line 65- Col. 10, Line 11) and a "high frequency expansion” with determined weighting (e.g., "spectral shaping") based upon the classification (Col. 9, Lines 28-51; Col. 9, Line 65- Col. 10, Line 11; Col. 12, Lines 9-20));
performing amplitude superposition on the audio subjected to bandwidth extension and the audio subjected to low-frequency restoration according to the high-frequency restoration weight and the low-frequency restoration weight (Col. 7, Line 18-39- "the expanded signal segment is formed based on the spectral values of the portions of the narrow band acoustic signal" where the resulting expanded acoustic signal "emulates the wide bandwidth spectral values of the speech that are missing as a consequence of the bandwidth limitations;" note that the expansion involves low frequency expansion below a cutoff frequency fc (i.e., spectral amplitude values are emulated/superimposed in a lower frequency range- see the lower frequency portions of the signal in Figs. 5A-C) and is based upon classification-based constraints (Col. 8, Lines 44-60 and Col. 9, Line 65- Col. 10, Line 11); note that such expansion involves high frequency expansion above a higher cutoff frequency fH (i.e., spectral amplitude values are emulated/superimposed in a higher frequency range- see the higher frequency portions of the signal in Fig. 7B) and is based upon classification-based constraints (Col. 9, Lines 28-51; Col. 9, Line 65- Col. 10, Line 11; Col. 12, Lines 9-20)); and
updating a phase with a frequency higher than a cut-off frequency in a result of the amplitude superposition to a phase with a frequency lower than the cut-off frequency, to obtain a restored audio (a wideband audio signal is restored at a frequency range at a particular frame-based time instance/phase (Col. 5, Line 60- Col. 6, Line 7) by updating/emulating from the narrowband audio signal from a high 2H cutoff frequency down to a frequency lower than a cutoff frequency in fL, Col. 7, Lines 18-39; Col. 9, Lines 6-17; and see Fig. 7B; note that the values of the expanded audio signal are shaped as informed by audio signal classification, Col. 9, Line 65- Col. 10, Line 11).
Claim 5 is directed towards a method claim containing multiple mutually exclusive contingent claim limitations (see "in response to the audio being classified as...music...human voice...noise." Per Ex parte Schulhauser, Appeal 2013-007847 (PTAB April 28, 2016), “[t]he Examiner did not need to present evidence of the obviousness of the method steps of claim 1 that are not required to be performed under a broadest reasonable interpretation of the claim." In the case of the present claim, the classification exclusively decides upon a class of audio signal in a single walk through the claimed method. Thus, under the broadest reasonable interpretation (BRI) and similar to alternative claim limitations, the prior art need only address one of the conditional limitations and responsive action to render the claimed invention unpatentable. With this interpretation in mind, with respect to Claim 5, Avendano discloses:
The audio processing method according to claim 1, wherein: in response to the audio being classified as music, the high-frequency restoration weight takes a value approaching a right boundary of a value range of the high-frequency restoration weight, and the low-frequency restoration weight takes a value approaching a left boundary of a value range of the low-frequency restoration weight; in response to the audio being classified as human voice, the high-frequency restoration weight takes a value approaching a left boundary of a value range of the high-frequency restoration weight, and the low-frequency restoration weight takes a value approaching a right boundary of a value range of the low-frequency restoration weight; and in response to the audio being classified as noise, the high-frequency restoration weight takes a value approaching a left boundary of a value range of the high-frequency restoration weight, and the low-frequency restoration weight takes a value approaching a left boundary of a value range of the low-frequency restoration weight (classification of the audio signal as being "dominated by noise," the bandwidth expansion of the noisy signal may be "prevented", Col. 9, Line 65- Col. 10, Line 36); Accordingly, in the case of noise expansion is zeroed out wherein this zeroing would constitute a “value approaching a left value of a value range” of constraint-based weighting of high and low band expansion in the form of zero as opposed to little no restraints for a speech signal (see “unrestricted”)).
With respect to Claim 7, Avendano further discloses:
The audio processing method according to claim 1, wherein classifying the audio according to the contents of the audio includes: classifying the audio according to a content of at least one of a history frame and a current frame in the audio (classification involves particular frames and also includes long term tracking such as a level difference over time, Col. 8, Lines 4-27).
Claim 10 recites an electronic device comprising a processor and memory connected to the processor storing processor-executable instructions for implementing the method of claim 1, and thus, is rejected under similar rationale. Furthermore, Avendano discloses method implementation on a device comprising a processor and memory storing processor-executable instructions (Col. 4, Lines 60-67 describing method implementation using a program stored in memory that is communicatively accessible by the processor).
Claim 16 contains subject matter similar to Claim 7, and thus, is rejected under similar rationale.
Claim 19 recites a non-transitory computer readable storage medium storing a processor-executable computer program for implementing the method of claim 1, and thus, is rejected under similar rationale. Furthermore, Avendano discloses a non-transitory computer readable storage medium storing a processor-executable computer program (Col. 2, Lines 60-67; Col. 13, Lines 13-20).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 6 and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Avendano, et al. in view of Eksler (U.S. PG Publication: 2020/0243100 A1).
With respect to Claim 6, Avendano teaches the method of expanding the bandwidth of an input audio signal from upper and lower cutoff frequencies as applied to Claim 1. It is noted that Avendano also utilizes the use of a high frequency bandwidth expansion model (Col. 9, Lines 18-27) and a low frequency restoration model (Col. 8, Lines 40-50). While Avendano performs bandwidth expansion above and below respective low and high frequency cutoffs, Avendano is silent on such cutoffs being "according to a coding mode and a code rate" in encoding of the audio. Eksler, however, notes that cut-off frequencies from which expansion occurs in Avendano depend "upon the operation mode and bit rate of the codec" (Paragraph 0045). Thus, the combination of Avendano yield expansion from different cutoff frequencies dependent upon the coding mode and rate.
Avendano and Eksler are analogous art because they are from a similar field of endeavor in audio signal processing utilizing bandwidth expansion. Thus, it would have been obvious to one of ordinary skill in the art, before the effective filing date, to consider coding rate and modes taught by Eksler in the cut-off frequency-based bandwidth expansion taught by Avendano to yield a predictable result of the ability to handle bandwidth expansion for different codecs based upon cut-off frequency.
Claim 15 contains subject matter similar to Claim 7, and thus, is rejected under similar rationale.
Potentially Allowable Subject Matter
Claims 2-4, 8-9, 11-14, 17-18, and 20 would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims and amended to overcome the preceding rejections under 35 U.S.C. 101 and 112 (also the claim objection in the particular case of claims 8 and 17).
Allowable Subject Matter
The following is a statement of reasons for the indication of potentially allowable subject matter.
With respect to Claim 2, the prior art of record taken individually or in a combination fails to explicitly teach or fairly suggest, the audio classification-based audio bandwidth expansion for both high and low frequency extension as set forth in claim 1 wherein the audio is classified as mixed sound, two sets of high-frequency restoration weights and low-frequency restoration weights are determined, the audio is split into a foreground signal and a background signal, and first and second sub-amplitude superposition is respectively performed on the foreground and background audio signals using the weights in the manner recited in claim 2.
Most Pertinent Prior Art:
While Avendano, et al. (U.S. Patent: 9,245,538) discloses an approach to lower and higher bandwidth extension of an input audio signal that is based upon audio signal classification such as speech or noise classes and a low frequency weighting (Col. 8, Lines 44-60; Col. 9, Lines 28-51; Col. 9, Line 65- Col. 10, Line 11; and Col. 12, Lines 9-20), Avendano is silent on mixed audio signal classification using the multiple weight sets for foreground and background audio signals high frequency bandwidth extension and low frequency bandwidth recovery. While other prior art such as Shenoy, et al. (U.S. PG Publication: 2014/0226842 A1) discloses multi-channel bandwidth extension in both a low and high frequency bands (Paragraph 0083-0084), additional prior art does not rely on the process set forth in claim 2 even when combined with the teachings of Avendano. Thus, the prior art of record fails to explicitly teach or fairly suggest the invention set forth in claim 8.
*Examiner note of caution on potential incorporation of claim 2 into independent claim 1: Note that the classification of a multi-channel audio signal in claim 2 and the corresponding processing containing allowable subject matter is part of a contingent limitation. While a single path contingency does not present a similar fact pattern to Ex parte Schulhauser and so does not invoke its claim construction in a method claim, if claim 2 were brough into claim 1, a multi-path series of contingent limitations would be created in claim 5. The effect of the addition of claim 5 to such an amended claim 1 would then invoke claim construction under Ex parte Schulhauser (see the explanation in the claim 5 rejection) meaning that while claim 1 would be potentially allowable, dependent claim 5 could be rejection since the allowable subject matter of an amended claim 1 would not be required to render the claimed invention obvious/anticipated. While an uncommon scenario, this type of amendment could result in an allowable claim 1 with a rejected claim 5 per Schulhauser claim construction. Applicant has a few options if they choose to advance prosecution in this manner- i) cancel claim 5 or ii) amend claim 5 in an iterative processing manner where the audio signal classified would be, for example, a “second audio”. Note that such considerations do not apply to corresponding system claim 14 because Schulhauser claim construction does not apply to system claims- “[t]he broadest reasonable interpretation of a system claim having structure that performs a function, which only needs to occur if a condition precedent is met, still requires structure for performing the function should the condition occur." See MPEP 2111.04 (II).
Claims 11 and 20 contain subject matter similar to Claim 2, and thus, contain potentially allowable subject matter under similar rationale. Note that the Schulhauser claim construction would not pertain to the system claim sets because they are not method claims. Per Schulhauser- “[t]he broadest reasonable interpretation of a system claim having structure that performs a function, which only needs to occur if a condition precedent is met, still requires structure for performing the function should the condition occur." Schulhauser at 14.
Claims 3-4 and 12-13 further limit and inherit limitations from a claim (claims 2 and 11) containing potentially allowable subject matter, and thus, also contain potentially allowable subject matter by virtue of their dependency.
With respect to Claim 8, the prior art of record taken individually or in a combination fails to explicitly teach or fairly suggest, the audio classification-based audio bandwidth expansion for both high and low frequency extension as set forth in claim 1 wherein phase is calculated according to the equation set forth in claim 8.
Most Pertinent Prior Art:
While Avendano, et al. (U.S. Patent: 9,245,538) discloses an approach to lower and higher bandwidth extension of an input audio signal that is based upon audio signal classification such as speech or noise classes (Col. 8, Lines 44-60; Col. 9, Lines 28-51; Col. 9, Line 65- Col. 10, Line 11; and Col. 12, Lines 9-20), Avendano is silent on the calculation of phase utilizing the equation set forth in claim 8. While other prior art such as Hersbach, et al. (U.S. PG Publication: 2006/0253209 A1) disclose the calculation of phase adjustment in bandwidth expansion (Paragraph 0063), Hersbach does not use the equation set forth in claim 8 in an application of lower and upper bandwidth expansion in an audio-classification based approach. Thus, the prior art of record fails to explicitly teach or fairly suggest the invention set forth in claim 8.
Claim 17 contains subject matter similar to Claim 8, and thus, is potentially allowable under similar rationale.
With respect to Claim 9, the prior art of record taken individually or in a combination fails to explicitly teach or fairly suggest, the audio classification-based audio bandwidth expansion for both high and low frequency extension as set forth in claim 1 wherein the low frequency restoration weight is calculated according to the equation set forth in equation 9.
Most Pertinent Prior Art:
While Avendano, et al. (U.S. Patent: 9,245,538) discloses an approach to lower and higher bandwidth extension of an input audio signal that is based upon audio signal classification such as speech or noise classes and a low frequency weighting (Col. 8, Lines 44-60; Col. 9, Lines 28-51; Col. 9, Line 65- Col. 10, Line 11; and Col. 12, Lines 9-20), Avendano is silent on the particular calculation of low frequency extension gains/weighting using the equation set forth in claim 9. Although another reference such Kikuiri, et al. (U.S. PG Publication: 2013/0339010 A1) teaches frequency envelope superposition where a scale factor of the low frequency band component "may be calculated using interpolation or extrapolation from at least one of the scale factor of the low frequency band component and the scale factor of the sub-band of the high frequency band" (Paragraph 0249), Kikuiri does not rely upon the equation set forth in claim 9 for identifying a low frequency restoration weighting. Thus, the prior art of record fails to explicitly teach or fairly suggest the invention set forth in claim 9.
Claim 18 contains subject matter similar to Claim 9, and thus, is potentially allowable under similar rationale.
With respect to Claim 14, the prior art of record taken individually or in a combination fails to explicitly teach or fairly suggest, the audio classification-based audio bandwidth expansion for both high and low frequency extension as set forth in claim 1 wherein multi-classification-based weighting is carried out as recited in claim 15 for music, voice, and noise signals. Note that since Schulhauser claim construction does not apply to method claims, the device must be programmed/configured to handle all the recited contingencies and corresponding actions and the combination of such triggers/actions is not provided by the prior art of record.
Most Pertinent Prior Art:
While Avendano, et al. (U.S. Patent: 9,245,538) discloses an approach to lower and higher bandwidth extension of an input audio signal that is based upon audio signal classification such as speech or noise classes where noise weighting as provided in claim 14 is taught (Col. 8, Lines 44-60; Col. 9, Lines 28-51; Col. 9, Line 65- Col. 10, Line 11; and Col. 12, Lines 9-20), Avendano does not teach the combination of the classification-based triggers/actions recited in claim 14. While additional prior art such as Subasingha, et al. (CA 2936987 C) teaches applying different types of side information including gain to speech vs. music signals (Paragraphs 0005, 0007, 0034, and 0041), Subasingha does not teach the combination of the classification-based triggers/actions recited in claim 14.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure: See the additional prior art references recited and described in the Potentially Allowable Subject Matter section.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JAMES S WOZNIAK whose telephone number is (571)272-7632. The examiner can normally be reached 7-3, off alternate Fridays.
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JAMES S. WOZNIAK
Primary Examiner
Art Unit 2655
/JAMES S WOZNIAK/Primary Examiner, Art Unit 2655