Add AMD support via ort alternative to trt

src/inference/face_embedder.hpp

@@ -0,0 +1,32 @@
+#pragma once
+#include "types.hpp"
+
+#include <memory>
+#include <vector>
+
+// ── IFaceEmbedder ─────────────────────────────────────────────────────────────
+// Backend-agnostic ArcFace embedder interface. The core application produces
+// 512-d L2-normalised embeddings through this interface without knowing whether
+// the implementation is ONNX Runtime or raw TensorRT.
+//
+// The concrete implementation is selected at compile time by CMake
+// (SAE_INFERENCE_BACKEND): exactly one of backends/ort_backend.cpp or
+// backends/trt_backend.cpp is compiled and provides make_face_embedder().
+
+struct Config;
+
+struct IFaceEmbedder {
+    virtual ~IFaceEmbedder() = default;
+    // Embed a batch of 112×112 BGR crops → one L2-normalised 512-d embedding
+    // each, parallel to the input.
+    virtual std::vector<Embedding> embed(const std::vector<cv::Mat>& crops) = 0;
+    // Largest batch the backend accepts in a single embed() call. TRT engines
+    // are capped by their build profile; ORT reports the configured batch size.
+    virtual int max_batch() const = 0;
+
+    Embedding embed_one(const cv::Mat& crop) { return embed({crop}).front(); }
+};
+
+// Construct the embedder for the compiled-in backend. Reads cfg.arcface_model,
+// cfg.arcface_engine, cfg.embed_batch_size and cfg.trt.
+std::unique_ptr<IFaceEmbedder> make_face_embedder(const Config& cfg);