C++ on jdcsen

stable-diffusion.cpp: Identity Conditioning in sd-server

Thu, 01 Jan 1970 00:33:46 +0000

Fork of stable-diffusion.cpp adding per-request reference-image identity conditioning (PhotoMaker v2 on SDXL bases, PuLID on Flux) to the sd-server HTTP surface. Upstream registered the flags but only the CLI ever populated them.
Eleven commits, about 1,900 lines added over 19 files. Roughly 89% lives in examples/server/; the core engine changes total 87 lines. sd-cli and the core library stay Python-free.
Reference-image encoding runs in-process through an embedded CPython interpreter (pybind11), behind two CMake flags that default to OFF so the vanilla build is unchanged.
Identity embeddings can be extracted once and re-injected: the round trip reproduces the image-path generation byte for byte at a fixed seed.
“No identity images” is proven to mean “no effect”: generations are md5-identical to the bare base model.
One upstream-worthy bug fix in core: an off-by-one in clip_preprocess center-cropping that crashed any CLIP-vision path on odd input dimensions.

Thu, 01 Jan 1970 00:33:44 +0000

Nova Sonic needed the speech framework’s pipelines delivered as a containerized gRPC service: audio and system prompts streaming in, inference requests streaming out. The team’s code had only ever been called through JNI.
Mapped gRPC C++’s bidirectional-streaming reactor onto the framework’s pipe abstraction once, as a reusable layer covering session setup and teardown, signal handling, graceful error handling and logging.
A new service needs under 300 lines of integration code: which pipe input receives request messages, and which pipe outputs become response messages. Adopted org-wide as the standard way to deploy a pipeline.
Established Protobuf and gRPC generated code as first-class CMake libraries in the framework’s build, so the same generated types are consumed by the pipeline’s nodes and by the server without duplicate-symbol conflicts.

Thu, 01 Jan 1970 00:33:43 +0000

Nodes in the C++ stream-processing framework behind Nova Sonic register themselves in a global registry through static initialization. No central list to edit, no explicit dependency from tools on the nodes they might load.
Registry is a thread-safe, function-local static constructed on first use, so registration is safe regardless of static initialization order across translation units.
Registration works by linking a node library or by LD_PRELOADing it. The development CLI can assemble a graph from a JSON definition using nodes it was never compiled against.
Pulled double duty as a dependency-inversion mechanism: consumers depend on the node interface, not on implementing libraries. Adopted across the organization and later picked up for embedded speech processing.

Thu, 01 Jan 1970 00:33:42 +0000

The legacy ASR engine, roughly 500k lines of C++, was built by its owners with GCC and plain CMake for the cloud. The on-device team consumed it as a library across about 7 ARM toolchains from the Android NDK plus 4 x86 gcc/clang variants, through a Conan-based build layer.
Before: on-device releases were hand-curated snapshots of the upstream engine, maintained in forks of every ASR package and re-merged periodically. Each release took days at minimum and often weeks, as toolchain-specific breakage surfaced and needed patches.
Fix: point all engine code at a single virtual build-system package. In the cloud dependency universe it resolves to bare CMake; in the device universe it resolves to the Conan layer, which drives the same CMake underneath. About 40 packages converted; one source tree builds for all 12 toolchains.
Kept it that way with a pre-merge analyzer that compiles every pull request against the device toolchains before it can land, so device compatibility is checked at merge time rather than discovered at release time.

Thu, 01 Jan 1970 00:33:39 +0000

A new L3Harris radio needed far more output dynamic range than the fielded RF front end it had to work with was designed to give.
The front end’s transmit chain had two gain stages: a coarse driver with three setpoints (low, medium, high) and a downstream fine stage adjustable in dB. The radio commanded a single power level. I designed and implemented the control software that turns that level into a safe setpoint pair for both stages.
Reaching the required range meant disabling the equipment’s built-in protection interlocks, so the software became the only thing standing between a command and hardware damage. Both stages maxed, or either past its limit, could destroy the amplifier and drop a pilot’s radio link.
Acted as de-facto software lead: direction for a small team, and project status reporting to organization management.

Thu, 01 Jan 1970 00:33:38 +0000

Led engineering teams to complete critical systems of a year-long engineering effort to develop an electric Formula race car.
Participated in and led design reviews for critical vehicle components.
Architected and implemented vehicle low-voltage systems, including safety circuits, vehicle networks, telemetry, and control.
Designed and built vehicle CCAs, working with EDA software (Eagle/KiCAD), from requirement collection to delivery.
Worked in close-knit, cross-functional teams to ensure effective and efficient concurrent development.