DETAILED ACTION
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 02/13/2026 has been entered.
Response to Arguments
On pages 10–18 of the Remarks, Applicant contends the cited prior art is deficient for failing to teach first and second interpretations of the syntax element would indicate whether the significant coefficient is a first or last significant (non-zero) coefficient. Examiner disagrees. As explained in the Advisory Action dated 01/21/2026 and explained again, infra, the prior art’s teaching of forward and reverse scan directions teaches Applicant’s averred feature. One must first realize that the prior art teaches coding a syntax element called the last significant coefficient. This syntax element allows the encoder or decoder to skip a group of leading zeros in a reverse scan in a conventional naturally coded image. This arrangement is depicted in Examiner’s top-right diagram, provided infra. Again, a key feature of the prior art is the somewhat arbitrary choice to concentrate the zero-valued coefficients at the beginning. This is also the stated preference of Applicant. See Nalci, cited under the Conclusion Section of this Office Action. Once the convention is determined that a scan should prefer the placement of the zero-valued coefficients at the beginning of the scan, one can easily see that the interpretation of the “last significant coefficient” changes depending on scan direction. Again, as depicted in Examiner’s Figure, provided infra, the top two diagrams demonstrate this concept. Given that in all cases the preference is the zeros are leading zeros (as opposed to trailing zeros), the top-left diagram illustrates that when the scan is a forward scan, the position of the last non-zero coefficient is, instead, the first non-zero coefficient from the DC origin. Similarly, again given that in all cases the preference is the zero are leading zeros (as opposed to trailing zeros), the top-right diagram illustrates that when the scan is a reverse scan, the position of the last non-zero coefficient is accurate, i.e. actually the last non-zero coefficient from the DC origin. To help expedite prosecution, the rejection now additionally relies on the teachings of Bross to bring home this concept being obvious to one of ordinary skill in the art. Bross’s para. [0006] teaches the preference is orienting the sequence of zeros to come before the first non-zero coefficient and further teaches that in service of that preference, in addition to backward/reverse diagonal scan “other scan pattern and directions can be employed as well.” This teaching of Bross, especially when combined with the teachings of Kahu and Choi, teaches or suggests Applicant’s feature of transform skip (identity transform) indicating a forward scan direction wherein such an indication further indicates that the LAST syntax element actually means the first significant coefficient when using the DC coefficient as the origin. See also rejections and explanation, infra. For all the foregoing reasons, Examiner is not persuaded of patentability. Thus, the rejections are sustained.
Other claims are not argued separately. Remarks, 19.
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 of this title, 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 1–4 and 7–20 are rejected under 35 U.S.C. 103 as being unpatentable over Choi (US 2025/0024081 A1), Kahu (US 2023/0283779 A1) and Bross (US 2023/0007252 A1).
While not believed necessary to sustain the rejection of the below claims, claims 1–4 and 7–20 shall be interpreted to be alternatively rejected in view of the teachings of Bross as cited with respect to the rejections of claims 5 and 6.
Regarding claim 1, the combination of Choi, Kahu, and Bross teaches or suggests a method comprising: accessing, by one or more processors, a bitstream representing video content; parsing, by the one or more processors, one or more flexible coefficient position (FCP) syntax from the bitstream, wherein the one or more FCP syntax indicate one or more index values (Examiner interprets this feature consistent with Applicant’s published paragraph [0056] as the position of the last significant coefficient; Examiner further notes that “last” is an arbitrary term in this art as the “last” significant coefficient is where the conventional coding algorithm “starts” to code the significant coefficients in reverse scan order; Evidence for this finding is provided under Conclusion Section of this Office Action; see particularly Bross, ¶ 0006, used as a dictionary-type reference; Choi, ¶ 0243: teaches signaling a position of a last significant coefficient using a single position value acting as an indexed position within a one-dimensional array; Choi, ¶ 0244: teaches positional (x, y, column, row) signaling of the last significant coefficient wherein the position can be assigned according to a reference system of a pre-defined scan order or the reverse of the pre-defined scan order wherein the forward or reverse scan can be determined based on, for example, block size, i.e. side information); determining, by the one or more processors, side information representing one or more characteristics of an encoded portion of the video content (Examiner interprets this feature consistent with Applicant’s published paragraph [0056], which explains the side information is any contextual information, including transform type; Kahu, ¶¶ 0154 and 0155: teach for VVC and AV2 that the when the block is coded in transform skip mode, such an indication means the last significant coefficient position is not signaled and the scanning order is a forward scanning order); interpreting, by the one or more processors, the one or more FCP syntax based on the side information, wherein interpreting the one or more FCP syntax comprises: selecting from among at least two different interpretations of the one or more FCP syntax based on the side information (Examiner interprets this feature in view of original claims 5 and 6, which essentially explain the side information is scan order information; Choi, ¶ 0244: teaches positional (x, y, column, row) signaling of the last significant coefficient wherein the position can be assigned according to a reference system of a pre-defined scan order or the reverse of the pre-defined scan order wherein the forward or reverse scan can be determined based on, for example, block size, i.e. side information), wherein the at least two different interpretations comprise: a first interpretation whereby a value indicated by the one or more FCP syntax represents a sequentially first significant coefficient position of the encoded portion of the video content in accordance with a coefficient scan order, a second interpretation whereby the value indicated by the one or more FCP syntax represents a sequentially last significant coefficient position of the encoded portion of the video content in accordance with the coefficient scan order (Examiner notes that, conventionally, the “last” significant coefficient in the art means last in view of a forward scanning direction from the low frequency DC coefficient (top-left) to the high frequency coefficient (bottom-right) and also notes that, conventionally, a reverse scan is used starting from the “last” coefficient backwards toward the DC coefficient so as to front-load the zeros (taking advantage of the “trailing zeros” phenomenon, but arbitrarily putting them at the beginning); All this means that the last coefficient is the first coefficient to get scanned in a reverse scanning order; See Examiner’s helpful diagram provided, infra, under the rejection of claim 1; Examiner further notes that adaptive coefficient scanning has been prior art for at least a decade prior to Applicant’s priority date such that any scan order is contemplated by the skilled artisan; Finally, Examiner notes that rotating or flipping the block prior to transforming and scanning has known utility such that a rotation or flip can obviously make a “last” coefficient a “first” coefficient and vice versa; Kahu, ¶ 0152: teaches reverse scanning order for levels of coefficients and a forward scanning order for the sign; Kahu, ¶ 0155: teaches that the scanning order is forward scanning in some implementations and is indicated by side information; see also concurrent explanation regarding the arbitrary nature of first vs. last in view of the teachings of Choi and Bross; Bross, ¶ 0006: teaches that the purpose of signaling the position of the first significant coefficient in a scan order is to avoid coding leading zeros), and determining a coefficient position with respect to the encoded portion of the video content based on the one or more index values and the selected interpretation of the one or more FCP syntax (Kahu, ¶¶ 0154 and 0155: teach that the side information, such as transform skip flag, influences whether the last significant coefficient position is signaled; Choi, ¶ 0244: teaches positional (x, y, column, row) signaling of the last significant coefficient wherein the position can be assigned according to a reference system of a pre-defined scan order or the reverse of the pre-defined scan order wherein the forward or reverse scan can be determined based on, for example, block size, i.e. side information); and decoding, by the one or more processors, the encoded portion of the video content according to the coefficient position (Examiner notes the position of the last coefficient signals many things to the decoder to help it decode the data, including whether other coefficient groups (sub-blocks) are all zero, how long a run of zeroes is for the highest frequency coefficients after the last significant (i.e. non-zero) coefficient, among others; Choi, ¶ 0246: teaches the last significant coefficient can, for example, be used to decide a type of transform to use).
One of ordinary skill in the art, before the effective filing date of the claimed invention would have been motivated to combine the elements taught by Choi, with those of Kahu, because both references are drawn to the same field of endeavor such that one wishing to practice the art of residual transform coding would be led to their relevant teachings regarding the coding of coefficient positions and because combining Choi’s teachings regarding the position of the last non-zero coefficient with Kahu’s teachings regarding transform skip represents a mere combination of prior art elements, according to known methods, to yield a predictable result. This rationale applies to all combinations of Choi and Kahu used in this Office Action unless otherwise noted.
One of ordinary skill in the art, before the effective filing date of the claimed invention would have been motivated to combine the elements taught by Choi and Kahu, with those of Bross, because all three references are drawn to the same field of endeavor such that one wishing to practice the art of residual transform coding would be led to their relevant teachings regarding the coding of coefficient positions and because combining Choi’s teachings regarding the position of the last non-zero coefficient with Bross’s teachings regarding the coding of the first (last) significant coefficient depending on scan order represents a mere combination of prior art elements, according to known methods, to yield a predictable result. This rationale applies to all combinations of Choi, Kahu, and Bross used in this Office Action unless otherwise noted.
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As explained in the Final Office Action dated 10/16/2025, both Choi and Bross teach changing the interpretation of the last significant coefficient information based on scan order. The prior art teaches, for example, that the last significant coefficient information, signaled for example as x, y positional information, would have a different interpretation based on whether the scan was a forward scan or a reverse scan. Obviously, signaling that the row and column of the last significant coefficient is (1, 1) in a forward scan means something different from a position of (1, 1) in a reverse scan if your origin (reference) changes based on scan order. See e.g. Filippov ‘881, Fig. 11. According to paragraphs [0061] and [0123] of Applicant's published Specification, Applicant explains the two claimed interpretations are that the signaled information either represents the last (LP) or first (FP) significant coefficient positions. Likewise, as the prior art explains, the “LAST” significant coefficient is signaled to differentiate between a group of significant (non-zero) coefficients and a group of zeros. Because the prior art convention is to prefer to group the zeros as leading zeros, for natural scenes a reverse scan order is typically selected. Bross, para. [0006]. Notice that the term, “trailing zeros” (using DC position as origin) can flip to the opposite meaning during a reverse scan, changing the “trailing zeros” to “leading zeros” (using scan order as origin). According to one NOT skilled in this art, he would assume the difference between first and last would be significant, i.e. the terms have opposite meaning, so how could they be the same. As Applicant's claim actually demonstrates in using the term, “interpretations,” it is simply an issue of differing semantics, but not actually representative of any technological advancement. Examiner has provided, supra, a diagram of significant coefficients and scanning order for consideration and further explanation. As one can see from the diagram provided by Examiner, when a scan is performed on a certain distribution of transform coefficients in a certain direction, the coefficient designated the “last significant coefficient” can change meaning (i.e. interpretation) to one having limited or no skill in this art. However, because the art uses the term, “last significant coefficient” not for the purpose of actually conveying last vs. first, but rather to convey where the leading or trailing zeros are in the dataset, the “interpretation” of what the “last significant coefficient” means is merely semantic. Regardless of whether the location of the “last significant coefficient” is actually the first or indeed the last according to some convention, the art, and signal processing more generally, is only concerned with conveying the location of demarcation between a string of zero-valued coefficients and non-zero-valued coefficients. As demonstrated in the provided diagram, whether or not it is semantically labeled first or last is not technologically significant because the demarcation is all that matters and is identical across the depicted scenarios. Notice that in the top two scenarios, the zeros are leading zeros. Notice in the bottom two scenarios, the zeros are trailing zeros. Notice that the two scenarios in the right-hand column depict natural images having the same data distribution but differing in scan direction. The cited prior art definitively teaches these scenarios in teaching forward and reverse scan directions (see Final Office Action, explaining Bross's paragraph [0006] teaches non-zeros concentrated in top left and tending to become zero in bottom-right corner). See also Filippov ‘881 Figs. 11 and 12. Fig. 11 shows that after reordering the coefficients according to a scan pattern, the position of the last significant coefficient changes, such that the interpretation of where the last significant coefficient is, changes according to scan pattern and scan direction. Fig. 12 shows different scan patterns, i.e. horizontal and vertical and how data distribution can influence which scan pattern might be better. As explained in Bross's paragraph [0006], an assumption often made is that the scan order (or direction) preferences ordering the group of zero-valued coefficients first (i.e. top-right scenario in Examiner’s diagram), but this convention is arbitrary and the preference could be to order the group of zero-valued coefficients after the significant coefficients. Importantly, Applicant has not demonstrated that anything novel is being presented in this application for patent. Also important, one must realize the universe of possibilities is two, i.e. the position represents either a first significant coefficient or a last significant coefficient, making Applicant's purported solution obvious to try to one of ordinary skill in the art. Either the last means the last or the last means the first. All Applicant appears to have done is fooled around with the semantic language the art uses to describe these concepts (the prior art demonstrably does not care about the semantics and uses “last significant coefficient” even though it could actually be the first significant coefficient while Applicant needlessly cares about the semantics) and then claims that a new way of describing the old technology amounts to a new technological advancement. Because there is no apparent underlying technical advancement presented by the patent application, the claimed subject matter is obvious under 35 U.S.C. 103 in view of the cited prior art and level of skill in this art.
Regarding claim 2, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein the encoded portion of the video content comprises at least one of a coding unit or a transform unit of the video content (Examiner notes this is extraordinarily basic in this art; Choi, Abstract: teaches transform blocks; Kahu, ¶¶ 0131–0132: teaches transform units and coding units).
Regarding claim 3, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein interpreting the one or more FCP syntax comprises: determining, based on the side information, whether the one or more FCP syntax represent (i) a sequentially first significant coefficient position of the encoded portion of the video content or (ii) a sequentially last significant coefficient position of the encoded portion of the video content (Examiner notes that, conventionally, the “last” significant coefficient in the art means last in view of a forward scanning direction and also notes that, conventionally, a reverse scan is used starting from the “last” coefficient backwards toward the DC coefficient; All this means that the last coefficient is the first coefficient to get scanned in a reverse scanning order; Examiner further notes that adaptive coefficient scanning has been prior art for at least a decade prior to Applicant’s priority date such that any scan order is contemplated by the skilled artisan; Finally, Examiner notes that rotating or flipping the block prior to transforming and scanning has known utilize such that a rotation or flip can obviously make a “last” coefficient a “first” coefficient and vice versa; Kahu, ¶ 0152: teaches reverse scanning order for levels of coefficients and a forward scanning order for the sign; Kahu, ¶ 0155: teaches that the scanning order is forward scanning in some implementations and is indicated by side information; see also treatment of claim 1, particularly the arbitrary nature of first vs. last in view of Choi and Bross).
Regarding claim 4, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein interpreting the one or more FCP syntax comprises: determining, based on the side information, whether to decode the encoded portion of the video content according to a forward coefficient scan order or a reverse coefficient scan order (Kahu, ¶ 0155: teaches, as side information, a transform skip scenario in which the coefficient scan order is forward instead of reverse when transform skip is not applied).
Regarding claim 5, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 4, wherein interpreting the one or more FCP syntax comprises determining, based on the side information, to decode the encoded portion of the video content according to the forward coefficient scan order (Bross, ¶ 0006: teaches forward and reverse scan orders are possible, which would obviously require side information to signal which type to use between encoder and decoder; Choi, ¶ 0244: teaches a pre-defined scan order or the reverse of the pre-defined scan order wherein the forward or reverse scan can be determined based on, for example, block size), and wherein decoding the encoded portion of the video content according to the coefficient position comprises performing a forward coefficient scan with respect to the encoded portion of the video content starting with the coefficient position, wherein the coefficient is a first coded coefficient position (Bross, ¶ 0006: teaches that the purpose of signaling the position of the first significant coefficient in a scan order is to avoid coding leading zeros).
Regarding claim 6, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 4, wherein interpreting the one or more FCP syntax comprises determining, based on the side information, to decode the encoded portion of the video content according to the reverse coefficient scan order (Bross, ¶ 0006: teaches forward and reverse scan orders are possible, which would obviously require side information to signal which type to use between encoder and decoder; Choi, ¶ 0244: teaches a pre-defined scan order or the reverse of the pre-defined scan order wherein the forward or reverse scan can be determined based on, for example, block size), and wherein decoding the encoded portion of the video content according to the coefficient position comprises performing a reverse coefficient scan with respect to the encoded portion of the video content starting with the coefficient position wherein the coefficient is a last coded coefficient position (Bross, ¶ 0006: teaches that the purpose of signaling the position of the first significant coefficient in a scan order is to avoid coding leading zeros and teaches that for the reverse scan the last coefficient is the position being signaled).
Regarding claim 7, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein the one or more FCP syntax indicate a single index value, and wherein the coefficient position is determined based on the single index value (Choi, ¶ 0243: teaches signaling a position of a last significant coefficient using a single position value acting as an indexed position within a one-dimensional array).
Regarding claim 8, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein the one or more FCP syntax indicate a plurality of index values, and wherein the coefficient position is determined based on the plurality of index values (Choi, ¶ 0244: teaches positional (x, y, column, row) signaling of the last significant coefficient wherein the position can be assigned according to a reference system of a pre-defined scan order or the reverse of the pre-defined scan order).
Regarding claim 9, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 8, wherein the coefficient position is determined based on one or more functions having at least some of the plurality of index values as inputs (Choi, ¶ 0244: teaches the position of the last significant coefficient can be based on a function utilizing syntax elements for x and y (i.e. column and row) index components).
Regarding claim 10, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein determining the side information comprises determining at least one of: a transform type of the encoded portion of the video content, coding block dimensions of the encoded portion of the video content, a transform unit size of the encoded portion of the video content, a plane type of the encoded portion of the video content, a coding mode of the encoded portion of the video content, or information regarding one or more additional encoded portions of the video content neighboring the encoded portion of the video content (Choi, ¶ 0244: teaches the size of the block can be side information for determining scan order and thus the position of the last significant coefficient; Kahu, ¶ 0155: teaches transform skip or identity transform can indicate no signaling of last coefficient position; see also Kahu, ¶ 0139: teaching the size and prediction mode influence transform kernels and transform kernels influence scan order and scan order influences whether last actually means first or last).
Regarding claim 11, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein determining the coefficient position with respect to the encoded portion of the video content comprises: determining a coefficient index value corresponding the coefficient position
Regarding claim 12, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein determining the coefficient position with respect to the encoded portion of the video content comprises: determining a coefficient column value corresponding the coefficient position (Choi, ¶ 0244: teaches positional (x, y, column, row) signaling of the last significant coefficient wherein the position can be assigned according to a reference system of a pre-defined scan order or the reverse of the pre-defined scan order).
Regarding claim 13, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein determining the coefficient position with respect to the encoded portion of the video content comprises: determining a coefficient row value corresponding the coefficient position (Choi, ¶ 0244: teaches positional (x, y, column, row) signaling of the last significant coefficient wherein the position can be assigned according to a reference system of a pre-defined scan order or the reverse of the pre-defined scan order).
Regarding claim 14, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein determining the coefficient position with respect to the encoded portion of the video content comprises: determining an x-coordinate corresponding the coefficient position (Choi, ¶ 0244: teaches positional (x, y, column, row) signaling of the last significant coefficient wherein the position can be assigned according to a reference system of a pre-defined scan order or the reverse of the pre-defined scan order).
Regarding claim 15, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein determining the coefficient position with respect to the encoded portion of the video content comprises: determining a y-coordinate corresponding the coefficient position (Choi, ¶ 0244: teaches positional (x, y, column, row) signaling of the last significant coefficient wherein the position can be assigned according to a reference system of a pre-defined scan order or the reverse of the pre-defined scan order).
Regarding claim 16, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein determining the side information comprises determining that the encoded portion of the video content is encoded according to at least one of a discrete cosine transform (DCT) type, asymmetric discrete sine transform (ADST) type, discrete sine transform (DST) type, flipped DCT type, flipped DST type, or flipped DST type (Kahu, ¶ 0138: teaches flipped transforms like flipped DSTs; see also Kahu, Table 2), and wherein interpreting the one or more FCP syntax comprises determining a sequentially last significant coefficient position of the encoded portion of the video content based on the one or more FCP syntax (Examiner interprets this feature consistent with Applicant’s published paragraph [0056] as the position of the last significant coefficient; Examiner further notes that “last” is an arbitrary term in this art as the “last” significant coefficient is where the conventional coding algorithm “starts” to code the significant coefficients in reverse scan order; Evidence for this finding is provided under Conclusion Section of this Office Action; see particularly Bross, ¶ 0006, used as a dictionary-type reference; Choi, ¶ 0243: teaches signaling a position of a last significant coefficient using a single position value acting as an indexed position within a one-dimensional array; Choi, ¶ 0244: teaches positional (x, y, column, row) signaling of the last significant coefficient wherein the position can be assigned according to a reference system of a pre-defined scan order or the reverse of the pre-defined scan order wherein the forward or reverse scan can be determined based on, for example, block size, i.e. side information).
Regarding claim 17, the combination of Choi, Kahu, and Bross teaches or suggests the method of claim 1, wherein determining the side information comprises determining that the encoded portion of the video content is encoded according to an identity transform type (Kahu, ¶ 0138: teaches flipped transforms like flipped DSTs; see also Kahu, Table 2), and wherein interpreting the one or more FCP syntax comprises determining a sequentially first significant coefficient position of the encoded portion of the video content based on the one or more FCP syntax (Examiner interprets this feature consistent with Applicant’s published paragraph [0056] as the position of the last significant coefficient; Examiner further notes that “last” is an arbitrary term in this art as the “last” significant coefficient is where the conventional coding algorithm “starts” to code the significant coefficients in reverse scan order; Evidence for this finding is provided under Conclusion Section of this Office Action; see particularly Bross, ¶ 0006, used as a dictionary-type reference; Choi, ¶ 0243: teaches signaling a position of a last significant coefficient using a single position value acting as an indexed position within a one-dimensional array; Choi, ¶ 0244: teaches positional (x, y, column, row) signaling of the last significant coefficient wherein the position can be assigned according to a reference system of a pre-defined scan order or the reverse of the pre-defined scan order wherein the forward or reverse scan can be determined based on, for example, block size, i.e. side information).
Claim 18 lists the same elements as claim 1, but in system form rather than method form. Therefore, the rationale for the rejection of claim 1 applies to the instant claim.
Claim 19 lists the same elements as claim 1, but in CRM form rather than method form. Therefore, the rationale for the rejection of claim 1 applies to the instant claim.
Claim 20 lists essentially the same elements as claim 1. Therefore, the rationale for the rejection of claim 1 applies to the instant claim.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Choi (US 2025/0024081 A1) teaches signaling a position of a last significant coefficient using a single position value acting as an indexed position within a one-dimensional array (¶ 0243) and teaches positional (x, y, column, row) signaling of the last significant coefficient wherein the position can be assigned according to a reference system of a pre-defined scan order or the reverse of the pre-defined scan order wherein the forward or reverse scan can be determined based on, for example, block size (¶ 0244).
Kahu (US 2023/0283779 A1) teaches the identity transform is identical to transform skip and teaches that both VVC and AV1/AV2 similarly propose modifications to residual coding when transform skip is applied wherein the scan order is the forward scanning order (e.g. ¶¶ 0154–0155).
Chen (US 2025/0055997 A1) teaches coding significant coefficients starts at the last significant coefficient and works backwards to the DC coefficient (¶ 0111).
Buys (US 2024/0015329 A1) teaches coefficient positions can be referenced by their indices (e.g. ¶ 0018).
Jeppe (US 2023/0361914 A1) teaches a “pivot position” that indicates that coefficients before that position are all zero while the coefficients after that position can be made up of non-zero coefficients (¶ 0030).
Koo (US 2021/0105477 A1) teaches the position of a coefficient can be indicated by an index according to a scan order (¶ 0197).
Filippov (US 2020/0404257 A1) teaches row and column indices can indicate a position of a coefficient (¶ 0225).
Filippov (US 2019/0020881 A1) teaches that the skilled artisan would have reason to determine both the first and last non-zero coefficient position indices (¶ 0216).
Bross (US 2023/0007252 A1) teaches the first (last) significant coefficient according to a scan order, teaches it is known that although the art is largely in agreement to use a backward/reverse scan, the skilled artisan knows of many other scan patterns and directions that can be used, and teaches the point of signaling the first (last) coefficient is, “To prevent coding and decoding a sequence of zeros before the first non-zero coefficient.” (e.g. ¶ 0006).
An (US 2017/0188029 A1) teaches flipped DCT means the index of transform coefficients are flipped too (¶ 0019).
Nalci et al., “Transform and Entropy Coding in AV2,” Feb 7, 2026. This publication explains EOB is for a reverse scan and BOB is for a forward scan wherein the goal is to skip preceding zeros (See Section L, page 12). Examiner notes overlapping authorship with the current application.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Michael J Hess whose telephone number is (571)270-7933. The examiner can normally be reached on Mon - Fri 9:00am-5:30pm.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, William Vaughn can be reached on (571)272-3922. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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MICHAEL J. HESS
Primary Examiner
Art Unit 2481
/MICHAEL J HESS/Primary Examiner, Art Unit 2481
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