1 files changed, 37 insertions, 0 deletions
diff --git a/third_party/jpeg-xl/lib/jxl/gamma_correct_test.cc b/third_party/jpeg-xl/lib/jxl/gamma_correct_test.cc
new file mode 100644
index 0000000000..131ec4fa83
--- /dev/null
+++ b/third_party/jpeg-xl/lib/jxl/gamma_correct_test.cc
@@ -0,0 +1,37 @@
+// Copyright (c) the JPEG XL Project Authors. All rights reserved.
+//
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include <stdlib.h>
+
+#include <algorithm>
+
+#include "lib/jxl/enc_gamma_correct.h"
+#include "lib/jxl/testing.h"
+
+namespace jxl {
+namespace {
+
+TEST(GammaCorrectTest, TestLinearToSrgbEdgeCases) {
+  EXPECT_EQ(0, LinearToSrgb8Direct(0.0));
+  EXPECT_NEAR(0, LinearToSrgb8Direct(1E-6f), 2E-5);
+  EXPECT_EQ(0, LinearToSrgb8Direct(-1E-6f));
+  EXPECT_EQ(0, LinearToSrgb8Direct(-1E6));
+  EXPECT_NEAR(1, LinearToSrgb8Direct(1 - 1E-6f), 1E-5);
+  EXPECT_EQ(1, LinearToSrgb8Direct(1 + 1E-6f));
+  EXPECT_EQ(1, LinearToSrgb8Direct(1E6));
+}
+
+TEST(GammaCorrectTest, TestRoundTrip) {
+  // NOLINTNEXTLINE(clang-analyzer-security.FloatLoopCounter)
+  for (double linear = 0.0; linear <= 1.0; linear += 1E-7) {
+    const double srgb = LinearToSrgb8Direct(linear);
+    const double linear2 = Srgb8ToLinearDirect(srgb);
+    ASSERT_LT(std::abs(linear - linear2), 2E-13)
+        << "linear = " << linear << ", linear2 = " << linear2;
+  }
+}
+
+}  // namespace
+}  // namespace jxl