This compares a line-by-line C# port of VLC’s Gaussian blur filter to the original C implementation and measures why and how much they differ. The blur is separable (horizontal then vertical), VLC’s original uses integer arithmetic and two-pass buffering, and the C# version is compiled with .NET Native AOT so it runs as a native VLC plugin and produces byte-identical frames on the same 1080p test clip on an 11th‑gen Core i7. The initial unoptimized C# port ran about 23% slower per frame than C; profiling showed the difference came from code generation (RyuJIT emitted more instructions, re-evaluating loop bounds and keeping sums in memory) rather than garbage collection or bounds checks.
Targeted changes and SIMD tuning closed almost all of that gap. Simple edits (precompute loop bounds, use nint) brought the line-by-line port within 8% of C, and further vectorized rewrites produced near-parity SIMD builds: tuned C ran ~3.05-6.62 ms/frame and tuned C# ~3.05-7.22 ms/frame, yielding about 240 vs 236 fps at sigma 4. The experiment shows C# is a realistic CPU-side choice when optimized against the JIT’s quirks, but C retains the final edge for the last 10% of performance. The work also exposed two VLC bugs and the filter is available in VLCLR.Filters for further testing.
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Linus Torvalds states that AI can assist competent developers but warns against unnecessary 'drive-by' patches. He emphasizes the importance of meaningful contributions over superficial fixes. (theregister.com)
Natural language programming is criticized for not reducing the complexity and care needed in coding, as machines still require precise instructions. Switching to native language interfaces would likely increase the workload for both humans and machines, rather than simplifying programming tasks. (cs.utexas.edu)
Jank is a Clojure dialect that offers seamless C++ interop, allowing developers to include C++ code directly and leverage its features without boilerplate. It features a Clang-based JIT compiler, native build system, and is optimized for game development and native performance tasks. (jank-lang.org)
Impossible Machines is a prototype that allows users to declaratively program physical mechanisms by describing desired outcomes. It generates mechanisms based on user instructions, enabling interactive design of physical systems. (impossiblemachines.xyz)
Zig uses two main approaches for polymorphism: runtime interfaces with dynamic dispatch and compile-time duck typing for static polymorphism. These methods offer different tradeoffs in performance and safety, with Zig emphasizing simplicity and compile-time checks over complex abstractions. (axelmagn.com)
AI can automate simple coding tasks, but it cannot replace the decision-making and understanding that software engineers provide. Building software still fundamentally involves determining what to create, which remains a complex human challenge. (thelastsoftwareengineer.substack.com)
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