libsdl-org/aom
Mar 2025 – Oct 2025
6 Months active
Languages Used
CC++
Technical Skills
AV1Algorithm OptimizationC++Image ProcessingPerformance OptimizationQuantization
Jingning Han
PROFILE
Jingning Han
Jingning worked on the libsdl-org/aom repository, delivering a series of AV1 encoder enhancements and stability improvements over six months. He implemented sharpness-driven quantization, adaptive transform search, and long-term reference statistics to improve encoding efficiency and image quality, using C and C++ for low-level optimization and algorithm tuning. His work addressed edge-case failures, assertion errors, and test instability by refining motion compensation, rate control, and chroma quantization logic. Through targeted bug fixes, code refactoring, and robust unit testing, Jingning improved maintainability and reliability, demonstrating depth in codec optimization, image processing, and performance tuning for both lossless and real-time encoding scenarios.
Overall Statistics
Feature vs Bugs
53%Features
Repository Contributions
24Total
Bugs
7
Commits
24
Features
8
Lines of code
742
Activity Months6
Your Network
4441 peopleSame Organization
@google.com4393
Benedict OdaiMember
Craig IngramMember
KayyuriMember
Scott SuarezMember
Agent2Agent (A2A) BotMember
Andreas AbelMember
Aadi KapurMember
Aadish GoelMember
Aahil MehtaMember
Shared Repositories
48
Alex DavicenkoMember
Alex FaxåMember
AnusuyaMember
apurveMember
Aras PranckeviciusMember
Athulya Raj Raji MohiniMember
BohanMember
Bernhard M. WiedemannMember
Cheng ChenMember
Work History
October 2025
2 Commits
Oct 1, 2025October 2025 monthly summary for libsdl-org/aom: Delivered a focused bug fix and code cleanup centered on AV1 intra encoding skip_txfm, improving correctness and stability with minimal risk to bitstream validity. No new features were introduced this month; the primary work improved encoder reliability and maintainability, laying groundwork for future enhancements.
2 Commits
Oct 1, 2025October 2025 monthly summary for libsdl-org/aom: Delivered a focused bug fix and code cleanup centered on AV1 intra encoding skip_txfm, improving correctness and stability with minimal risk to bitstream validity. No new features were introduced this month; the primary work improved encoder reliability and maintainability, laying groundwork for future enhancements.
October 2025
September 2025
1 Commits • 1 Features
Sep 1, 2025September 2025: Focused AV1 encoder enhancement for Shorts in libsdl-org/aom. Introduced a new lt_coded_error statistic in first-pass encoding statistics to evaluate prediction error when using a long-term reference frame, updated accumulation/normalization to incorporate the metric, and integrated last2_frame as a potential long-term reference. This codec rework targets better bitrate control and encoding efficiency for Shorts.
September 2025
1 Commits • 1 Features
Sep 1, 2025September 2025: Focused AV1 encoder enhancement for Shorts in libsdl-org/aom. Introduced a new lt_coded_error statistic in first-pass encoding statistics to evaluate prediction error when using a long-term reference frame, updated accumulation/normalization to incorporate the metric, and integrated last2_frame as a potential long-term reference. This codec rework targets better bitrate control and encoding efficiency for Shorts.
July 2025
2 Commits
Jul 1, 2025July 2025 monthly summary for libsdl-org/aom focusing on chroma delta quantization handling bug fix in lossless vs real-time modes; two commits applied to stabilize behavior and associated test adjustments.
2 Commits
Jul 1, 2025July 2025 monthly summary for libsdl-org/aom focusing on chroma delta quantization handling bug fix in lossless vs real-time modes; two commits applied to stabilize behavior and associated test adjustments.
July 2025
May 2025
8 Commits • 4 Features
May 1, 2025May 2025 monthly summary for libsdl-org/aom focused on performance improvements for sharpness=3, adaptive RD tuning, high bit-depth variance stats, and robustness. Key outcomes include reduced compute load during transform search, adaptive temporal filtering, enhanced variance statistics for high bit-depth, and fixes to boundary handling and partition pruning to improve stability.
May 2025
8 Commits • 4 Features
May 1, 2025May 2025 monthly summary for libsdl-org/aom focused on performance improvements for sharpness=3, adaptive RD tuning, high bit-depth variance stats, and robustness. Key outcomes include reduced compute load during transform search, adaptive temporal filtering, enhanced variance statistics for high bit-depth, and fixes to boundary handling and partition pruning to improve stability.
April 2025
5 Commits • 1 Features
Apr 1, 2025April 2025 performance summary for libsdl-org/aom: Delivered major AV1 encoder quality and stability improvements with targeted commits, fixed critical constraint handling to prevent assertion failures, and addressed static-analysis warnings to improve maintainability. The work produced tangible business value through higher encoding quality, fewer edge-case failures, and clearer interfaces.
5 Commits • 1 Features
Apr 1, 2025April 2025 performance summary for libsdl-org/aom: Delivered major AV1 encoder quality and stability improvements with targeted commits, fixed critical constraint handling to prevent assertion failures, and addressed static-analysis warnings to improve maintainability. The work produced tangible business value through higher encoding quality, fewer edge-case failures, and clearer interfaces.
April 2025
March 2025
6 Commits • 2 Features
Mar 1, 2025March 2025 monthly summary for libsdl-org/aom focusing on sharpness-driven encoder improvements and test stabilization. Key contributions include implementing a sharpness-based encoder quantization with motion-vector range constraints, introducing sharpness-aware intra-mode search optimization, and stabilizing the sharpness test suite with thresholds adjustments. These changes collectively enhance encoding efficiency, reduce artifacts for sharper imagery, and improve test reliability and confidence in performance metrics.
March 2025
6 Commits • 2 Features
Mar 1, 2025March 2025 monthly summary for libsdl-org/aom focusing on sharpness-driven encoder improvements and test stabilization. Key contributions include implementing a sharpness-based encoder quantization with motion-vector range constraints, introducing sharpness-aware intra-mode search optimization, and stabilizing the sharpness test suite with thresholds adjustments. These changes collectively enhance encoding efficiency, reduce artifacts for sharper imagery, and improve test reliability and confidence in performance metrics.
Activity
Loading activity data...
Quality Metrics
Correctness84.6%
Maintainability83.4%
Architecture79.2%
Performance72.6%
AI Usage20.0%
Skills & Technologies
Programming Languages
CC++
Technical Skills
AV1AV1 CodecAlgorithm OptimizationBug FixingC ProgrammingC++Code AnalysisCode RefactoringCodec OptimizationImage ProcessingLossless CompressionLow-level OptimizationMotion CompensationNaming ConventionsPerformance Optimization
Repositories Contributed To
Overview of all repositories you've contributed to across your timeline