feat: add plasma-face-unlock

tests/test_store.cpp

@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+// The face store: what goes in comes back out, matching picks the right
+// sample, and learning from unlocks stays within its bounds.
+
+#include "store.h"
+
+#include <QFileInfo>
+#include <QTemporaryDir>
+
+#include <cmath>
+#include <cstdio>
+#include <random>
+
+namespace
+{
+int failures = 0;
+
+void check(bool ok, const char *what)
+{
+    std::printf("%s  %s\n", ok ? "ok  " : "FAIL", what);
+    failures += !ok;
+}
+
+Embedding randomUnit(std::mt19937 &rng)
+{
+    std::normal_distribution<float> n;
+    Embedding e(Vision::EmbeddingSize);
+    float norm = 0;
+    for (float &v : e) {
+        v = n(rng);
+        norm += v * v;
+    }
+    for (float &v : e) {
+        v /= std::sqrt(norm);
+    }
+    return e;
+}
+
+// A vector about `similarity` away from `base`.
+Embedding near(const Embedding &base, float similarity, std::mt19937 &rng)
+{
+    Embedding other = randomUnit(rng);
+    Embedding out(base.size());
+    const float w = std::sqrt(1 - similarity * similarity);
+    float norm = 0;
+    for (size_t i = 0; i < base.size(); ++i) {
+        out[i] = similarity * base[i] + w * other[i];
+        norm += out[i] * out[i];
+    }
+    for (float &v : out) {
+        v /= std::sqrt(norm);
+    }
+    return out;
+}
+} // namespace
+
+int main()
+{
+    std::mt19937 rng(7);
+    QTemporaryDir dir;
+    const FaceStore store(dir.path());
+
+    Identity a;
+    a.id = FaceStore::newId();
+    a.name = QStringLiteral("Felix mit Brille");
+    a.created = 1758550000;
+    a.noseT = 0.57f;
+    a.eyes = 0.41f;
+    const Embedding faceA = randomUnit(rng);
+    for (int i = 0; i < 5; ++i) {
+        a.samples.append({near(faceA, 0.8f, rng), QStringLiteral("center"), 1758550000 + i});
+    }
+
+    Identity b;
+    b.id = FaceStore::newId();
+    b.name = QStringLiteral("Other");
+    const Embedding faceB = randomUnit(rng);
+    b.samples.append({faceB, QStringLiteral("center"), 1});
+
+    QString error;
+    check(store.save(1000, {a, b}, &error), "save");
+    const QString file = dir.filePath(QStringLiteral("users/1000.json"));
+    check(QFileInfo(file).permissions() == (QFileDevice::ReadOwner | QFileDevice::WriteOwner | QFileDevice::ReadUser | QFileDevice::WriteUser),
+          "the file is readable by its owner only");
+
+    const QList<Identity> loaded = store.load(1000, &error);
+    check(loaded.size() == 2, "both faces come back");
+    check(loaded.value(0).name == a.name && loaded.value(0).samples.size() == 5, "names and samples survive");
+    check(std::abs(loaded.value(0).noseT - 0.57f) < 1e-6f && std::abs(loaded.value(0).eyes - 0.41f) < 1e-6f, "attention baselines survive");
+    check(Vision::similarity(loaded.value(0).samples.value(0).embedding, a.samples.value(0).embedding) > 0.9999f, "embeddings survive exactly");
+    check(store.load(1001).isEmpty(), "another user has no faces");
+
+    const FaceMatch m = FaceStore::bestMatch(loaded, near(faceA, 0.9f, rng));
+    check(m.identity == 0 && m.score > 0.6f, "the right face matches");
+    const FaceMatch stranger = FaceStore::bestMatch(loaded, randomUnit(rng));
+    check(stranger.score < 0.4f, "a stranger does not");
+
+    QList<Identity> disabled = loaded;
+    disabled[0].enabled = false;
+    check(FaceStore::bestMatch(disabled, near(faceA, 0.9f, rng)).identity != 0, "a face that is turned off never matches");
+
+    Identity learning = loaded.value(0);
+    check(!FaceStore::adapt(learning, learning.samples.value(0).embedding, 5), "nothing new: nothing learned");
+    int added = 0;
+    for (int i = 0; i < 40; ++i) {
+        added += FaceStore::adapt(learning, near(faceA, 0.6f, rng), 10 + i);
+    }
+    check(added > FaceStore::MaxAdaptive, "new looks are learned");
+    check(learning.adaptiveCount() == FaceStore::MaxAdaptive, "but only so many of them are kept");
+    int setup = 0;
+    for (const FaceSample &s : learning.samples) {
+        setup += s.pose != u"adaptive";
+    }
+    check(setup == 5, "the samples from the setup are never replaced");
+
+    check(store.save(1000, {}, &error) && !QFileInfo::exists(file), "saving nothing removes the file");
+
+    std::printf("\n%s\n", failures ? "SOME CHECKS FAILED" : "all checks passed");
+    return failures ? 1 : 0;
+}