Joint Collaborative Team on Video Coding (jct-vc) of itu-t sg16 wp3 and iso/iec jtc1/SC29/WG11
CE3: Coefficient scanning and coding
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- Bu səhifədəki naviqasiya:
- 4.3.2Contributions
- 4.4CE4: Quantization matrices
- 5.3HM coding performance
4.3CE3: Coefficient scanning and coding4.3.1SummaryJCTVC-I0023 CE3: Summary report of Core Experiment on coefficient scanning and coding [V. Sze, T. Nguyen, K. Panusopone, Y. Piao, J. Sole (CE coordinators)] During the opening discussion on this topic, it was suggested to first make a decision between two basic types of coefficient coding proposals before proceeding with full discussion of the contributions in each of the two types. Neighbouring or template based context selection for significance maps – . e.g. I0296 vs. I0406 vs. the current mixed HM approach.
A somewhat more parallel-friendly version of H0228 was also tested in the CE. For two-bin parallelism the gain would drop to −0.3/−0.2/−0.1% (and with more parallelism, more loss). It was asserted that the H0228 scheme has more gain at high bit rates than at lower bit rates. The current approach is something of a mixture of these two approaches, with the template approach (i.e. the more parallel-friendly approach) for the 4x4 and 8x8 block sizes and the position-based approach for all others. The current mixed approach would require more text (probably not a significant issue). It was remarked that at high bit rates, the complexity advantage would have a noticeable impact on run-times.
The other issue in the CE is I0303. 4.3.2ContributionsJCTVC-I0174 CE3.1.2: Parallel context assignment for significance map coding [T.-D. Chuang, C.-W. Hsu, C.-Y. Chen, Y.-W. Huang, S. Lei (MediaTek)] JCTVC-I0443 CE3: Cross-check results for subtest 3.1.2 ( I0174 & H0286 ) [W. -J. Chien (Qualcomm)] JCTVC-I0051CE3: Cross-check of Parallel context assignment for significance map coding (H0286) by Mediatek [C. Rosewarne, V. Kolesnikov, M. Maeda (Canon)] JCTVC-I0203 CE3: Test results for Subtest 3.1.3. (H0352) [V. Sze (TI)] JCTVC-I0442 CE3: Cross-check results for subtest 3.1.3 (I0203 & H0352 ) [W. -J. Chien (Qualcomm)] JCTVC-I0547 CE3: Cross-check results for subtest 3.1.2 and 3.1.3 (H0228) [J. Chen, J. Sole (Qualcomm)] [late] JCTVC-I0312 CE3: Cross-check results for subtest 3.1.4 (H0427) [H. Sasai, K. Terada, T. Nishi (Panasonic)] [late] JCTVC-I0048 CE3: Subtest 1 - Cross-check of JCTVC-H0427 (Method 2 – 4 Bins) [C. Yeo, Y. H. Tan (I2R)] JCTVC-I0303 CE3 subtest 2.1: context assignment for parallel coefficient level coding [W.-J. Chien, J. Chen, J. Sole, M. Karczewicz (Qualcomm)] Proposes to remove a dependency on two consecutively coded bins, as previously proposed in H0550. The reported coding efficiency impact was 0.1–0.2% loss. It was discussed whether the overall complexity benefit is substantial. It was suggested that some other proposals are related – i.e. would limit the claimed benefit, as they would reduce the average or worst-case usage. Those other proposals were discussed, and this subject was then discussed again. No action was then taken on this. JCTVC-I0206 CE3: Cross-check results for Subtest 3.2.1 (H0550 / I0303) [V. Sze (TI)] [late] The cross-check report notes that the initialization values for CABAC were modified. It was remarked that the measured coding efficiency loss might be larger if this was not done. The proponent of I0303 indicated that there would not really be a significant difference due to this. JCTVC-I0406 CE3: Report for CE3 Subtest 3 [T. Nguyen, H. Kirchhoffer, C. Bartnik, D. Marpe (Fraunhofer HHI)] JCTVC-I0047 CE3: Subtest 3 - Cross-check of JCTVC-H0228 [C. Yeo, Y. H. Tan (I2R)] JCTVC-I0307 CE3: Cross-check results for subtest 3.3.1 (H0228) [Y. Piao, E. Alshina, J. H. Park (Samsung)] JCTVC-I0310 CE3: Cross-check results for subtest 3.3.4 (H0228) [Y. Piao, E. Alshina, J. H. Park (Samsung)] JCTVC-I0324 CE3 test 3: Parallelization with bit-plane coding (H0228) [J. Sole, V. Seregin, W.-J. Chien, J. Chen, M. Karczewicz (Qualcomm)] JCTVC-I0207 CE3: Cross-check of JCTVC-I0324 on parallelization with bit-plane coding [V. Sze (TI)] [late] JCTVC-I0469 CE3: Cross-check of Subtest 3 on Parallelization and Throughput [N. Nguyen, T. Ji, D. He, G. Martin-Cocher] [late] 4.4CE4: Quantization matrices4.4.1SummaryThis CE was cancelled. 4.4.2ContributionsThis CE was cancelled. 5Non-CE Technical Contributions5.1Clarification and Bug Fix Issues5.2HM settings and common test conditionsNo contributions were noted to be specific to this subject area. 5.3HM coding performanceJCTVC-I0407 Compression Performance of HEVC WD6 based on ITU-R Rec. BT.1210 K. Kawamura, T. Yoshino, S. Naito (KDDI) This contribution provides experimental results to evaluate the coding performance of HEVC under the sufficient coverage of test materials. Those employed materials are recommended in ITU-R Recommendation BT.1210-4. Experimental results reportedly show that HM6.0 can achieve BD-Bit rate of 21%, 36% and 43% for the all intra, the random access and the low delay main-configurations, respectively, compared to JM18.3. It is additionally clarified that the gains are decreased to 15%, 24% and 29% especially for sequences comprised by many fine objects with complex motions. The test was on materials in BT.1210-4 and BT.2245, all 60p (4:2:2), as follows:.
JCTVC-I0409 Comparison of Compression Performance of HEVC Draft 6 with AVC High Profile [B. Li (USTC), G. J. Sullivan, J. Xu (Microsoft)] This contribution is a further study of the relative objective (i.e. PSNR-based) compression performance of HEVC Main Profile and AVC High Profile. It builds upon the prior work reported in JCTVC-G399 and JCTVC-H0360, updating the results by using the latest available reference software (JM-18.3 and HM-6.0) and configuration common conditions. Relative to the results reported at the preceding meeting in JCTVC-H0360, this contribution uses a somewhat stronger anchor AVC encoding in its low-delay comparison (approximately 8% better in coding efficiency). Experimental results reportedly show that 1) for the Main Profile all-intra configuration, HM-6.0 can save about 22% in bit rate; 2) for the Main Profile random-access configuration, HM-6.0 can save about 33% in bit rate; and 3) for the Main Profile low-delay configuration, HM-6.0 can save about 36% in bit rate when compared with JM-18.3. In addition to testing the HEVC Main Profile, the contribution also analyzes the coding efficiency and runtime impacts of five features in the draft HEVC standard that are not in its Main profile: LM Chroma, AMP, NSQT, ALF, and 10 bit encoding. It is noted that these results are based on 6:1:1 weighted YUV PSNR measurements, which are an imperfect substitute for subjective quality assessment, and that the subjective performance of HEVC may actually be generally somewhat better than its objective (PSNR) performance may indicate.
This contribution provides information about the HEVC still picture coding performance. The intra coding of HEVC is reported to provide on average 56% objective bit rate reduction over a widely utilized JPEG implementation. It is further reported that HEVC intra coding achieves a 34% average objective bit rate reduction over the official JPEG XR reference implementation. The differences are reportedly larger for Class F content (67% and 48% with respect to JPEG and JPEG XR, respectively). Regarding encoder optimization, the software was operated in default mode.
(Mmentioned in the context of JCTVC-I0063. ) This input document provides an intra-only coding performance analysis of HM 6.0 by using a test set of photographic still images. Furthermore, compression performance comparison with H.264/AVC, WebP, JPEG 2000, and JPEG XR for still image coding is provided. JPEG baseline is also included and serves as the anchor for the coding performance evaluation. This used a dDifferent test set than I0461 (the Kodak set) – Intra-only BR reduction was somewhat lower than with the common test set (16% vs. AVC). Regarding encoder optimization, the software was operated in default mode.
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