1 files changed, 94 insertions, 0 deletions
diff --git a/third_party/jpeg-xl/lib/jxl/cms/transfer_functions_test.cc b/third_party/jpeg-xl/lib/jxl/cms/transfer_functions_test.cc
new file mode 100644
index 0000000000..26de409a4e
--- /dev/null
+++ b/third_party/jpeg-xl/lib/jxl/cms/transfer_functions_test.cc
@@ -0,0 +1,94 @@
+// 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.
+
+#undef HWY_TARGET_INCLUDE
+#define HWY_TARGET_INCLUDE "lib/jxl/cms/transfer_functions_test.cc"
+#include "lib/jxl/cms/transfer_functions.h"
+
+#include <cstdio>
+#include <hwy/foreach_target.h>
+
+#include "lib/jxl/base/random.h"
+#include "lib/jxl/cms/transfer_functions-inl.h"
+#include "lib/jxl/testing.h"
+
+// Test utils
+#include <hwy/highway.h>
+#include <hwy/tests/hwy_gtest.h>
+HWY_BEFORE_NAMESPACE();
+namespace jxl {
+namespace HWY_NAMESPACE {
+namespace {
+
+HWY_NOINLINE void TestPqEncodedFromDisplay() {
+  constexpr size_t kNumTrials = 1 << 23;
+  Rng rng(1);
+  float max_abs_err = 0;
+  HWY_FULL(float) d;
+  for (size_t i = 0; i < kNumTrials; i++) {
+    double intensity = 11000.0 + rng.UniformF(-150.0f, 150.0f);
+    TF_PQ tf_pq(intensity);
+    const float f = rng.UniformF(0.0f, 1.0f);
+    const float actual = GetLane(tf_pq.EncodedFromDisplay(d, Set(d, f)));
+    const float expected = TF_PQ_Base::EncodedFromDisplay(intensity, f);
+    const float abs_err = std::abs(expected - actual);
+    EXPECT_LT(abs_err, 5e-7) << "f = " << f;
+    max_abs_err = std::max(max_abs_err, abs_err);
+  }
+  printf("max abs err %e\n", static_cast<double>(max_abs_err));
+}
+
+HWY_NOINLINE void TestHlgEncodedFromDisplay() {
+  constexpr size_t kNumTrials = 1 << 23;
+  Rng rng(1);
+  float max_abs_err = 0;
+  HWY_FULL(float) d;
+  for (size_t i = 0; i < kNumTrials; i++) {
+    const float f = rng.UniformF(0.0f, 1.0f);
+    const float actual = GetLane(TF_HLG().EncodedFromDisplay(d, Set(d, f)));
+    const float expected = TF_HLG_Base::EncodedFromDisplay(f);
+    const float abs_err = std::abs(expected - actual);
+    EXPECT_LT(abs_err, 4e-7) << "f = " << f;
+    max_abs_err = std::max(max_abs_err, abs_err);
+  }
+  printf("max abs err %e\n", static_cast<double>(max_abs_err));
+}
+
+HWY_NOINLINE void TestPqDisplayFromEncoded() {
+  constexpr size_t kNumTrials = 1 << 23;
+  Rng rng(1);
+  float max_abs_err = 0;
+  HWY_FULL(float) d;
+  for (size_t i = 0; i < kNumTrials; i++) {
+    double intensity = 11000.0 + rng.UniformF(-150.0f, 150.0f);
+    TF_PQ tf_pq(intensity);
+    const float f = rng.UniformF(0.0f, 1.0f);
+    const float actual = GetLane(tf_pq.DisplayFromEncoded(d, Set(d, f)));
+    const float expected = TF_PQ_Base::DisplayFromEncoded(intensity, f);
+    const float abs_err = std::abs(expected - actual);
+    EXPECT_LT(abs_err, 3E-6) << "f = " << f;
+    max_abs_err = std::max(max_abs_err, abs_err);
+  }
+  printf("max abs err %e\n", static_cast<double>(max_abs_err));
+}
+
+}  // namespace
+// NOLINTNEXTLINE(google-readability-namespace-comments)
+}  // namespace HWY_NAMESPACE
+}  // namespace jxl
+HWY_AFTER_NAMESPACE();
+
+#if HWY_ONCE
+namespace jxl {
+
+class TransferFunctionsTargetTest : public hwy::TestWithParamTarget {};
+HWY_TARGET_INSTANTIATE_TEST_SUITE_P(TransferFunctionsTargetTest);
+
+HWY_EXPORT_AND_TEST_P(TransferFunctionsTargetTest, TestPqEncodedFromDisplay);
+HWY_EXPORT_AND_TEST_P(TransferFunctionsTargetTest, TestHlgEncodedFromDisplay);
+HWY_EXPORT_AND_TEST_P(TransferFunctionsTargetTest, TestPqDisplayFromEncoded);
+
+}  // namespace jxl
+#endif  // HWY_ONCE