Embedding VisionLab into an Existing MES Controller

Challenge

A machine builder had an existing Qt-based MES controller managing conveyor, PLC, and sensor data. They needed to add circle-measurement capability for a new product line — but without restructuring the host application or taking on a heavy OpenCV/PyTorch dependency.

The requirement: plug in vision as an isolated process, callable from existing C++ code.

Solution: VisionLab Plugin SDK

VisionLab ships a pure-C plugin SDK (PluginHostLauncher.h + PluginHostInterface.h) that manages the entire lifecycle of the vision plugin process. Communication uses Windows shared memory (IPC), keeping inter-process latency under 2 ms.

Integration in 8 Lines

#include "PluginHostLauncher.h"
#include "PluginHostInterface.h"

// 1. Launch the plugin process
PluginHostLauncher* launcher =
    PluginHostLauncher_Create("visionlab.exe");
if (!PluginHostLauncher_Launch(launcher, 5000)) return;

// 2. Get communication handle
PluginHostHandle* host = PluginHostLauncher_GetHost(launcher);

// 3. Send image + receive result
PluginHostImage img = { frame.data, frame.cols, frame.rows, 1 };
PluginHostResult result;
PluginHost_SendAndWait(host, &img,
    R"({"roi_cx":320,"roi_cy":240,"roi_inner":80,"roi_outer":120})",
    &result, 3000);

// 4. Parse JSON result
printf("Center: %s\n", result.data);

// 5. Cleanup (auto-kills plugin process)
PluginHostLauncher_Destroy(launcher);

UI Embedding Mode

For applications that want the VisionLab parameter-tuning UI embedded directly into a window panel, the SDK provides a one-call embed API:

PluginHostLauncher_SetUIMode(launcher, PLUGIN_UI_EMBEDDED);
PluginHostLauncher_EmbedInto(launcher,
    (void*)container->winId(), 0, 0, 640, 480);

The plugin window is reparented into the host container — no separate window appears.

Architecture

MES Controller (host, existing code)
    │
    │   PluginHostLauncher_Create / Launch
    ▼
VisionLab.exe (plugin process)
    │  Shared Memory IPC  │
    │  < 2 ms latency     │
    ▼
AlgoLib (circle/line/defect algorithms)
    │
    ▼
JSON result → back to host via IPC

Outcome

The machine builder shipped the new product line on schedule, without touching their existing motion-control or sensor-fusion code.