EXCEEDS logo
Exceeds
Zhao Zhili

PROFILE

Zhao Zhili

Zhao Zhili contributed to the ossrs/ffmpeg-webrtc and FFmpeg/FFmpeg repositories by engineering robust media processing features and stability improvements across video and audio pipelines. He developed hardware-accelerated encoding and decoding paths, optimized performance for AArch64 and WebAssembly targets, and enhanced color metadata handling for HEVC and VVC codecs. Using C and assembly language, Zhao refactored build systems, improved error handling, and expanded test coverage to ensure cross-platform reliability. His work addressed low-level optimizations, codec integration, and memory management, resulting in more maintainable codebases and resilient streaming workflows. The depth of his contributions reflects strong expertise in multimedia frameworks.

Overall Statistics

Feature vs Bugs

54%Features

Repository Contributions

159Total
Bugs
40
Commits
159
Features
47
Lines of code
10,870
Activity Months15

Work History

January 2026

11 Commits • 5 Features

Jan 1, 2026

January 2026 - FFmpeg/FFmpeg delivered targeted performance improvements, stability fixes, and cross‑platform enhancements across decoding, encoding, and tooling. Key deliverables include NEON‑accelerated PNG decoding DSP with tests for AArch64, and associated correctness verification; a performance optimization in the bswap_buf loop to improve throughput; Vulkan integration fixes including callback prototype corrections and scale filter dependency; Android timing reliability improvements by disabling the PMCCNTR timer; and cross‑cutting tuning of logging and encoder usability with ABI stability updates. These changes collectively improve decoding performance, cross‑platform reliability, and developer experience, enabling broader adoption and easier integration with x265 and D3D12‑based workflows.

December 2025

9 Commits • 2 Features

Dec 1, 2025

December 2025 – FFmpeg/FFmpeg: Delivered reliability, performance, and maintainability improvements across demuxing, filtering, and image processing. Key outcomes include adding raw video demuxer stride and pixel-format handling enhancements, stabilizing OpenCV and FFmpeg filters, hardening NEON paths against out-of-bounds reads, and improving dimension calculations with AV_CEIL_RSHIFT. These efforts reduce memory leaks, prevent crashes due to null pointers, improve frame timestamp handling, and boost overall media processing performance.

November 2025

18 Commits • 5 Features

Nov 1, 2025

November 2025: Delivered targeted stability improvements, performance optimizations, and feature expansions across FFmpeg/FFmpeg. Major work focused on hardware-accelerated paths (VideoToolbox, NVENC, VAAPI, D3D12VA), robust media format handling, and added test coverage to validate new capabilities. Resulting changes reduce crash surfaces, improve encoding latency, and broaden platform support for production pipelines.

October 2025

2 Commits

Oct 1, 2025

October 2025 FFmpeg/FFmpeg monthly summary: Implemented stability improvements in the video decoding path by fix ing initialization of video dimensions for certain codecs when decoders are enabled and correcting handling of RASL frames in VVC decoding to avoid false recovery alarms. These changes reduce playback glitches and false error signals in production pipelines. The work involved analyzing avformat/avcodec initialization, refining decoder enablement logic, and patching VVC decoding routines; committed as two patches across the FFmpeg tree, with references to the following commits.

September 2025

25 Commits • 3 Features

Sep 1, 2025

September 2025 FFmpeg monthly summary (2025-09) for FFmpeg/FFmpeg. Key features delivered include HXVS demuxer support with fate test coverage (avformat: add hxvs demuxer; tests/fate/demux: add hxvs test case), refactor/cleanup of CUDA-accelerated filters (avfilter/vf_bilateral_cuda) with simplified window_size checks and streamlined frame management, and enhanced frame handling/alpha control in chromakey_cuda (avfilter/vf_chromakey_cuda). A substantive data-path fix was applied to MP4 handling in hybrid_fragmented mode (avformat/movenc: remove mvex from final mp4 in hybrid_fragmented mode). Additional improvements include AVToolbox bitrate handling in low_delay mode (avcodec/videotoolboxenc), and multiple build/compatibility fixes across PCM, SWScale, docs, and mov. Major bug fixes addressed around decoder stability (RKMPP: input queue overflow and EAGAIN during flushing), FLV/FLAC/movenc/test maintenance (memory leaks and warnings), and timing adjustments to sidx handling (avformat/mov: avoid shifting sidx_pts; avformat/movenc: revert sidx earliest_presentation_time timing). These efforts yield stronger stability, broader test coverage, and improved cross-component reliability, enabling more robust production deployments.

August 2025

10 Commits • 5 Features

Aug 1, 2025

FFmpeg/FFmpeg — August 2025 monthly summary: Focused on reliability, performance, and quality improvements across decoding, encoding, and media pipelines. Delivered Windows/MSVC build reliability fixes, significant AArch64 performance optimizations (VVC decoding and color-detection paths), robustness enhancements for multibyte UTF-8 transcription and decoding checks, and more flexible encoding quality controls. Also strengthened governance and initialization stability for color-detection components and updated CODEOWNERS to reflect new patterns. These changes reduce build failures, improve runtime performance on ARM64, enhance output correctness, and provide clearer ownership for media-codec related areas.

July 2025

6 Commits • 2 Features

Jul 1, 2025

July 2025 performance summary for ossrs/ffmpeg-webrtc: Implemented OpenHarmony hardware-accelerated video processing (ohcodec) with device support and H.264/HEVC encoders/decoders; refined color processing by aligning Vibrance filter luma coefficients with external shader implementations; hardened media handling with MXF frame offset validation; stabilized Blackdetect header guards to improve build reliability. These work items deliver tangible performance gains on OpenHarmony devices, increase system stability, and reduce crash risk in edge-case media workflows.

June 2025

12 Commits • 2 Features

Jun 1, 2025

June 2025 performance summary: Across ossrs/ffmpeg-webrtc and FFmpeg/FFmpeg, delivered targeted features and critical fixes with clear business value. Key feature delivered: SIMD-accelerated HEVC decoding in WebAssembly via sao_band_filter and sao_edge_filter, enabling lower CPU usage and smoother WebRTC streams. Major fixes included correcting edit-list handling for hybrid fragmented MP4 in movenc and preventing integer overflow in TLS MTU configuration, improving reliability and robustness of networked media workflows. Ongoing maintenance and quality improvements across codecs, demuxers, and tooling increased consistency and maintainability. Additionally, VVC on AArch64 benefited from NEON-accelerated derive_bdof_vx_vy, delivering notable performance gains.

May 2025

8 Commits • 3 Features

May 1, 2025

May 2025 monthly summary for ossrs/ffmpeg-webrtc: Delivered core feature and stability improvements focusing on HEVC color metadata handling, Movenc fragmentation robustness, and build system organization. Resulted in more reliable color processing, improved fragmented MP4 generation performance, and cleaner build configuration for easier maintenance and future work.

April 2025

9 Commits • 5 Features

Apr 1, 2025

April 2025 (2025-04) monthly summary for ossrs/ffmpeg-webrtc focused on performance, reliability, and developer experience across video processing and streaming pipelines. Key features delivered and bugs fixed include targeted optimizations, robustness improvements, and clearer operational feedback, delivering measurable business value in throughput, error reporting, and user experience. Key accomplishments: - Implemented AArch64 NEON-accelerated SAO band filter for 16x16 blocks and wired it through HEVC/VVC DSP initializations to boost processing throughput. - Optimized Mov demuxer seeking by disabling small DTS sample selection when interleaved_read is off, reducing unnecessary seeks and startup latency. - Centralized HLS key handling with a new read_key function and refactored open_input, improving error reporting and robustness for encrypted streams. - Enhanced HTTP connection reuse by logging protocol mismatches at INFO level, improving transparency and troubleshooting for re-used connections. - Fixed h264_mp4toannexb side data handling to process only AVCC extradata, preventing mixed bitstream formats and downstream errors. Additional notes: - Minor documentation correction for mptestsrc output size (512x512) and a bug fix for MediaCodec format field reset on getInt32 failure to avoid stale crop information after format changes were observed in CI validation.

March 2025

7 Commits • 2 Features

Mar 1, 2025

March 2025 progress across ossrs/ffmpeg-webrtc focused on reliability, HDR support, and alpha-channel encoding. Key outcomes include a bug fix for FFmpeg Bitstream Filter parameter propagation to AVCodecContext when BSFs are enabled by the decoder; hardened HDR metadata support and robustness in FLV demuxer/muxer with improved color metadata parsing and error handling; introduced alpha-channel support in HEVC encoding by adding AYUV as a candidate pix_fmt and updating encoder creation; expanded test coverage for HDR scenarios in FLV flows.

February 2025

13 Commits • 5 Features

Feb 1, 2025

February 2025 monthly summary for ossrs/ffmpeg-webrtc. Focused on feature enrichment, broader codec/muxer coverage, and robustness improvements to support production pipelines while delivering measurable business value. Key features delivered include: 1) Subtitle Logging Enhancement for Unsupported Subtitles in Matroska Muxer—logs the human-readable subtitle codec name alongside its ID to improve troubleshooting and user feedback (commit 4307008b9a81ae3322f742f557192ccc52517be2). 2) HEVC Alpha Channel Support—adds alpha channel handling for HEVC decoding, including auxiliary scalability type support and dedicated alpha layer processing, with tests (commits d367016d3ccaa225ab76b22afb8d17f5500304ff; f926b6045522c5f9887a108f5d9b6ae017e9ba02; d1616046258acb990c61d82dd40218067f0a4de8). 3) AVS3 Codec and Muxer Support—enables AVS3 in movenc and maps AVS3 IDs for correct MP4/MOV muxing (commits a053516e644e07d1e625901539671c3682c7af49; 2d7966aee158682d3112c0f293254a96ef26950c). 4) HEVC Decoder Enhancements—scalability parsing refinements, ARM64 IDCT NEON optimizations, and robustness improvements for corrupted streams, including output_corrupt/showall flags (commits d3220ed8181d6729bfe867da2890c9b3eada6731; 5977bff569b1e1feecf681059472f4106c1573cb; 3e9777dc7546425651bc265a49187d6bbb42bdf4; bc1a3bfd2cbc01ffa386312662af8a014890d861). 5) Extradata Processing for libuavs3d—refactored sequence header handling and added extradata decoding to initialize frame rate, dimensions, and color information (commit 5a32496962853beb302ebce307821c7c960fa54f). Major bugs fixed include: Frame Buffer Pointer Safety Bug Fix to prevent incorrect pointer comparisons across types (commit 88d9ecaa7b792edc9baf22d0f4eca2071cafd91e) and WASM Conflict Prevention in FFV1 Parser via renaming parser close function and updating the related pointer (commit 584c41a4accdb729480e52d9829b34c1f9964bc9). Overall, the month delivered broader media format support, safer decoding paths, and stronger build/compatibility hygiene, translating to higher reliability in production deployments and clearer debugging signals for users. Technologies/skills demonstrated include FFmpeg core components (avformat, avcodec, avutil), HEVC and AVS3 internals, ARM64 NEON optimization, extradata handling in libuavs3d, and WebAssembly build hygiene.

January 2025

6 Commits • 3 Features

Jan 1, 2025

January 2025 monthly summary for ossrs/ffmpeg-webrtc focused on delivering configurable encoding controls, improving resilience across the encoding/decoding pipeline, and hardening seek/fallback behaviors. Highlights include cross-codec feature work, stability improvements, and increased business value through quality and reliability gains.

December 2024

9 Commits • 2 Features

Dec 1, 2024

December 2024 (Month: 2024-12) performance summary for ossrs/ffmpeg-webrtc. Focused on delivering high-value features, stabilizing cross-platform builds, and improving media pipeline reliability. Key work included substantial AArch64 VVC core improvements, refactoring for robust MediaCodec encoder output handling, targeted build fixes for Vulkan GLSLang and CUVID-related hardware contexts, and test-suite simplifications to improve maintainability in WASI environments. All work aligns with the goal of faster feature delivery, greater codec/hardware compatibility, and more reliable streaming pipelines.

November 2024

14 Commits • 3 Features

Nov 1, 2024

November 2024 (ossrs/ffmpeg-webrtc) delivered key performance, stability, and portability enhancements. Core media pipeline improvements include: (1) MediaCodec operating_rate option added to both decoder and encoder to optimize performance when operating above frame rate; (2) asynchronous mode introduced for the MediaCodec wrapper (JNI/NDK) and encoder to enable non-blocking I/O, improving responsiveness and throughput; (3) WebAssembly (WASM) support with SIMD128 optimizations, including WASM SIMD-enabled HEVC IDCT and related checkasm enhancements; (4) cross-platform build stability and memory alignment improvements to strengthen portability across x86/x64 and MSVC, fix alignment-related issues, and reduce build failures. Overall, these changes enhance runtime performance, broaden deployment options (including browser/WASM contexts), and reduce maintenance overhead through more reliable builds and portable code.

Activity

Loading activity data...

Quality Metrics

Correctness93.0%
Maintainability89.2%
Architecture87.8%
Performance85.6%
AI Usage20.0%

Skills & Technologies

Programming Languages

AssemblyCMakMakefileShellTeXTexinfoText

Technical Skills

AArch64 architectureAPI designARM ArchitectureARM AssemblyARM NEONARM NEON IntrinsicsAVCodecAVFormatAlpha Channel SupportAndroid NDKAssembly Language ProgrammingAssembly OptimizationAssembly ProgrammingAssembly programmingAsynchronous Programming

Repositories Contributed To

2 repos

Overview of all repositories you've contributed to across your timeline

ossrs/ffmpeg-webrtc

Nov 2024 Jul 2025
9 Months active

Languages Used

AssemblyCMakefileTextMakTexinfo

Technical Skills

Android NDKAsynchronous ProgrammingBuild SystemBuild System ConfigurationBuild SystemsC programming

FFmpeg/FFmpeg

Jun 2025 Jan 2026
7 Months active

Languages Used

AssemblyCShellTextMakefileTeX

Technical Skills

ARM ArchitectureAssembly Language ProgrammingNEON IntrinsicsPerformance OptimizationVideo Codec OptimizationARM Assembly

Generated by Exceeds AIThis report is designed for sharing and indexing