Files
scene-actor-extraction/tests/test_similarity.cpp
T
dtourolleandClaude Opus 5 ffdad9873d test: tag the untagged suites; correct two stale headers
Four test files and one node header carried no TRACES tag, so the
requirements they verify read as implemented-but-unverified. Tagging a
test is what distinguishes the two.

test_calibration.cpp is AR-023; its three [report] cases verify GR-003
and are tagged separately, since the report is fitted from the same
distributions but is its own requirement. test_similarity.cpp is the CI
half of AR-026 — equivalence against hand-computed dot products, where
throughput at scale is AR-027 and cannot run on this host.
test_face_tracker.cpp is AR-007 and AR-008.

Two headers described code that no longer exists. face_aligner_node.hpp
still documented the RANSAC fit AR-005 replaced with an Umeyama
least-squares fit over all five points — not merely out of date but the
opposite of what the file does, and it reads as a rationale for
discarding the landmarks AR-030 measures. test_face_tracker.cpp still
described the park/revive branch AR-008 deleted, and the raw-cosine
cut_revive_sim that guarded it, which AR-024 retired.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

TRACES: AR-005, AR-007, AR-008, AR-023, AR-026, AR-030 | GR-003 | SR-001, SR-002
2026-07-31 22:47:59 +02:00

98 lines
3.4 KiB
C++

// TRACES: AR-026 | SR-001
//
// Unit tests for the CPU reference similarity engine (backends/gemm_backend.cpp,
// SAE_GEMM_CPU) and the l2_normalise helper. All pure, GPU-free, model-free.
//
// This is the CI half of AR-026: equivalence between the GEMM path and
// hand-computed dot products on small input. Throughput at scale (AR-027) is T4
// and cannot run here.
#include <catch2/catch_test_macros.hpp>
#include <catch2/matchers/catch_matchers_floating_point.hpp>
#include "face_utils.hpp"
#include "inference/similarity.hpp"
#include <array>
#include <cmath>
#include <vector>
using Catch::Matchers::WithinAbs;
namespace {
// A 512-d embedding that is 1.0 in one slot and 0 elsewhere (already unit-norm).
std::array<float, 512> one_hot(int slot) {
std::array<float, 512> e{};
e[slot] = 1.0f;
return e;
}
} // namespace
TEST_CASE("l2_normalise produces a unit vector", "[similarity]") {
std::array<float, 512> raw{};
raw[0] = 3.0f;
raw[1] = 4.0f; // norm 5
Embedding n = l2_normalise(raw.data());
CHECK_THAT(n[0], WithinAbs(0.6f, 1e-6f));
CHECK_THAT(n[1], WithinAbs(0.8f, 1e-6f));
float norm = 0.f;
for (float v : n) norm += v * v;
CHECK_THAT(std::sqrt(norm), WithinAbs(1.0f, 1e-6f));
}
TEST_CASE("l2_normalise guards against a zero vector", "[similarity]") {
std::array<float, 512> zero{};
Embedding n = l2_normalise(zero.data());
for (float v : n) CHECK(v == 0.0f); // 0 / 1e-6 == 0, no NaN
}
TEST_CASE("CPU similarity engine matches hand-computed dot products", "[similarity]") {
// Gallery of three orthonormal one-hot embeddings.
std::vector<float> gallery;
for (int slot : {0, 1, 2}) {
auto e = one_hot(slot);
gallery.insert(gallery.end(), e.begin(), e.end());
}
const int n_gallery = 3;
const int max_faces = 2;
auto engine = make_similarity_engine(gallery.data(), n_gallery, max_faces);
REQUIRE(engine->max_faces() == max_faces);
// Two query faces: face0 == gallery row 1, face1 is 45° between rows 0 and 2.
std::vector<float> query(static_cast<size_t>(max_faces) * 512, 0.0f);
query[1] = 1.0f; // face0: one-hot slot 1
const float s = std::sqrt(0.5f);
query[512 + 0] = s; // face1: (1/√2, 0, 1/√2, …)
query[512 + 2] = s;
const float* S = engine->compute(query.data(), 2);
// Column-major: S[g + f*n_gallery].
// face0 vs gallery {0,1,2} → {0, 1, 0}
CHECK_THAT(S[0 + 0 * n_gallery], WithinAbs(0.0f, 1e-6f));
CHECK_THAT(S[1 + 0 * n_gallery], WithinAbs(1.0f, 1e-6f));
CHECK_THAT(S[2 + 0 * n_gallery], WithinAbs(0.0f, 1e-6f));
// face1 vs gallery {0,1,2} → {1/√2, 0, 1/√2}
CHECK_THAT(S[0 + 1 * n_gallery], WithinAbs(s, 1e-6f));
CHECK_THAT(S[1 + 1 * n_gallery], WithinAbs(0.0f, 1e-6f));
CHECK_THAT(S[2 + 1 * n_gallery], WithinAbs(s, 1e-6f));
}
TEST_CASE("CPU similarity engine rejects too many faces", "[similarity]") {
auto e = one_hot(0);
auto engine = make_similarity_engine(e.data(), /*n_gallery=*/1, /*max_faces=*/1);
std::array<float, 512 * 2> q{};
CHECK_THROWS(engine->compute(q.data(), 2));
}
TEST_CASE("CPU similarity engine handles zero query faces", "[similarity]") {
auto e = one_hot(0);
auto engine = make_similarity_engine(e.data(), 1, 4);
// n_faces == 0 must not read the (null) query pointer.
CHECK_NOTHROW(engine->compute(nullptr, 0));
}