commit 3812533636fe4d5327b99fb51198444912ab0e9f
author Nick Deakin <deakin@google.com> Mon Dec 12 15:48:24 2022 -0500
committer Nick Deakin <deakin@google.com> Mon Dec 12 16:03:42 2022 -0500
tree 468af67ff4a0009f9196aff07a7457d1c7846385
parent d1d227421b46588ec52c91c89e71a8e945b6ec21

A couple recoverymap fixes.

Fix decoding of P010 narrow range code points. Also fix scaling for
input to OETF during application of the map.

NOTE: tests pass, although there is still an expected failure for
encoding against just P010 input (API-0), sine toneMap() isn't
implemented yet.

Bug: 252835416, 261479255
Test: libjpegrecoverymap_test passes
Change-Id: Ibfd036c6c0cd55de7c5886e32fff69f461cf45d9

libs/jpegrecoverymap/recoverymap.cpp

diff --git a/libs/jpegrecoverymap/recoverymap.cpp b/libs/jpegrecoverymap/recoverymap.cpp
index c9ac921..74bb512 100644
--- a/libs/jpegrecoverymap/recoverymap.cpp
+++ b/libs/jpegrecoverymap/recoverymap.cpp
@@ -562,7 +562,7 @@
       float recovery = sampleMap(uncompressed_recovery_map, kMapDimensionScaleFactor, x, y);
       Color rgb_hdr = applyRecovery(rgb_sdr, recovery, metadata->rangeScalingFactor);
 
-      Color rgb_gamma_hdr = hdrOetf(rgb_hdr);
+      Color rgb_gamma_hdr = hdrOetf(rgb_hdr / metadata->rangeScalingFactor);
       uint32_t rgba1010102 = colorToRgba1010102(rgb_gamma_hdr);
 
       size_t pixel_idx =  x + y * width;

libs/jpegrecoverymap/recoverymapmath.cpp

diff --git a/libs/jpegrecoverymap/recoverymapmath.cpp b/libs/jpegrecoverymap/recoverymapmath.cpp
index e838f43..9ed2949 100644
--- a/libs/jpegrecoverymap/recoverymapmath.cpp
+++ b/libs/jpegrecoverymap/recoverymapmath.cpp
@@ -336,9 +336,9 @@
                   >> 6;
 
   // Conversions include taking narrow-range into account.
-  return {{{ static_cast<float>(y_uint) / 940.0f,
-             (static_cast<float>(u_uint) - 64.0f) / 940.0f - 0.5f,
-             (static_cast<float>(v_uint) - 64.0f) / 940.0f - 0.5f }}};
+  return {{{ (static_cast<float>(y_uint) - 64.0f) / 876.0f,
+             (static_cast<float>(u_uint) - 64.0f) / 896.0f - 0.5f,
+             (static_cast<float>(v_uint) - 64.0f) / 896.0f - 0.5f }}};
 }
 
 typedef Color (*getPixelFn)(jr_uncompressed_ptr, size_t, size_t);

libs/jpegrecoverymap/tests/recoverymapmath_test.cpp

diff --git a/libs/jpegrecoverymap/tests/recoverymapmath_test.cpp b/libs/jpegrecoverymap/tests/recoverymapmath_test.cpp
index 169201c..f8dd490 100644
--- a/libs/jpegrecoverymap/tests/recoverymapmath_test.cpp
+++ b/libs/jpegrecoverymap/tests/recoverymapmath_test.cpp
@@ -36,9 +36,9 @@
   }
 
   Color P010(uint16_t y, uint16_t u, uint16_t v) {
-      return {{{ static_cast<float>(y) / 940.0f,
-                 (static_cast<float>(u) - 64.0f) / 940.0f - 0.5f,
-                 (static_cast<float>(v) - 64.0f) / 940.0f - 0.5f }}};
+      return {{{ (static_cast<float>(y) - 64.0f) / 876.0f,
+                 (static_cast<float>(u) - 64.0f) / 896.0f - 0.5f,
+                 (static_cast<float>(v) - 64.0f) / 896.0f - 0.5f }}};
   }
 
   float Map(uint8_t e) {
@@ -821,7 +821,6 @@
               bt2100Luminance(RgbBlue()) * kPqMaxNits, LuminanceEpsilon());
 }
 
-//Color Recover(Color yuv_gamma, float recovery, float range_scaling_factor) {
 TEST_F(RecoveryMapMathTest, ApplyMap) {
   EXPECT_RGB_EQ(Recover(YuvWhite(), 1.0f, 8.0f),
                 RgbWhite() * 8.0f);