diff --git a/DEPS b/DEPS
index 1bf9a63..ad72b2f 100644
--- a/DEPS
+++ b/DEPS
@@ -111,7 +111,7 @@
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling pdfium_tests
   # and whatever else without interference from each other.
-  'pdfium_tests_revision': '422552c1cf9795131684aa34973a3873e94c4937',
+  'pdfium_tests_revision': 'b67d79fef155c0c44be240a4fde07f15adac5a4f',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling skia
   # and whatever else without interference from each other.
diff --git a/core/fxcodec/jbig2/jbig2_embeddertest.cpp b/core/fxcodec/jbig2/jbig2_embeddertest.cpp
index c897a28..8e52dbf 100644
--- a/core/fxcodec/jbig2/jbig2_embeddertest.cpp
+++ b/core/fxcodec/jbig2/jbig2_embeddertest.cpp
@@ -21,6 +21,6 @@
   FPDF_PAGE page = LoadPage(0);
   ASSERT_TRUE(page);
   ScopedFPDFBitmap bitmap = RenderLoadedPage(page);
-  CompareBitmap(bitmap.get(), 691, 432, "24d75af646f8772c5ee7ced260452ae4");
+  CompareBitmap(bitmap.get(), 691, 432, "726c2b8c89df0ab40627322d1dddd521");
   UnloadPage(page);
 }
diff --git a/core/fxge/dib/cstretchengine.cpp b/core/fxge/dib/cstretchengine.cpp
index a0674cc..15ab57a 100644
--- a/core/fxge/dib/cstretchengine.cpp
+++ b/core/fxge/dib/cstretchengine.cpp
@@ -75,9 +75,7 @@
 
   m_DestMin = dest_min;
 
-  // TODO(tsepez): test results are sensitive to `scale` being a double
-  // rather than a float with an initial value no more precise than float.
-  const double scale = static_cast<float>(src_len) / dest_len;
+  const double scale = static_cast<double>(src_len) / dest_len;
   const double base = dest_len < 0 ? src_len : 0;
   const size_t weight_count = static_cast<size_t>(ceil(fabs(scale))) + 1;
   m_ItemSizeBytes = PixelWeight::TotalBytesForWeightCount(weight_count);
@@ -89,15 +87,13 @@
 
   m_WeightTablesSizeBytes = dest_range * m_ItemSizeBytes;
   m_WeightTables.resize(m_WeightTablesSizeBytes);
-  if (options.bNoSmoothing || fabs(static_cast<float>(scale)) < 1.0f) {
+  if (options.bNoSmoothing || fabs(scale) < 1.0f) {
     for (int dest_pixel = dest_min; dest_pixel < dest_max; ++dest_pixel) {
       PixelWeight& pixel_weights = *GetPixelWeight(dest_pixel);
       double src_pos = dest_pixel * scale + scale / 2 + base;
       if (bilinear) {
-        int src_start =
-            static_cast<int>(floor(static_cast<float>(src_pos) - 1.0f / 2));
-        int src_end =
-            static_cast<int>(floor(static_cast<float>(src_pos) + 1.0f / 2));
+        int src_start = static_cast<int>(floor(src_pos - 0.5));
+        int src_end = static_cast<int>(floor(src_pos + 0.5));
         src_start = std::max(src_start, src_min);
         src_end = std::min(src_end, src_max - 1);
         pixel_weights.SetStartEnd(src_start, src_end, weight_count);
@@ -105,13 +101,13 @@
           // Always room for one weight per size calculation.
           pixel_weights.m_Weights[0] = kFixedPointOne;
         } else {
-          pixel_weights.m_Weights[1] = FixedFromFloat(
-              static_cast<float>(src_pos - pixel_weights.m_SrcStart - 0.5f));
+          pixel_weights.m_Weights[1] =
+              FixedFromDouble(src_pos - pixel_weights.m_SrcStart - 0.5f);
           pixel_weights.m_Weights[0] =
               kFixedPointOne - pixel_weights.m_Weights[1];
         }
       } else {
-        int pixel_pos = static_cast<int>(floor(static_cast<float>(src_pos)));
+        int pixel_pos = static_cast<int>(floor(src_pos));
         int src_start = std::max(pixel_pos, src_min);
         int src_end = std::min(pixel_pos, src_max - 1);
         pixel_weights.SetStartEnd(src_start, src_end, weight_count);
@@ -130,7 +126,9 @@
     start_i = std::max(start_i, src_min);
     end_i = std::min(end_i, src_max - 1);
     pixel_weights.SetStartEnd(start_i, end_i, weight_count);
-    for (int j = start_i; j <= end_i; ++j) {
+    uint32_t remaining = kFixedPointOne;
+    double rounding_error = 0.0;
+    for (int j = start_i; j < end_i; ++j) {
       double dest_start = (j - base) / scale;
       double dest_end = (j + 1 - base) / scale;
       if (dest_start > dest_end)
@@ -138,11 +136,18 @@
       double area_start = std::max(dest_start, static_cast<double>(dest_pixel));
       double area_end = std::min(dest_end, static_cast<double>(dest_pixel + 1));
       double weight = std::max(0.0, area_end - area_start);
-      if (weight == 0 && j == end_i) {
-        pixel_weights.RemoveLastWeight();
-        break;
-      }
-      pixel_weights.SetWeightForPosition(j, FixedFromFloat(weight));
+      uint32_t fixed_weight = FixedFromDouble(weight + rounding_error);
+      pixel_weights.SetWeightForPosition(j, fixed_weight);
+      remaining -= fixed_weight;
+      rounding_error =
+          weight - static_cast<double>(fixed_weight) / kFixedPointOne;
+    }
+    // Note: underflow is defined behaviour for unsigned types and will
+    // result in an out-of-range value.
+    if (remaining && remaining <= kFixedPointOne) {
+      pixel_weights.SetWeightForPosition(end_i, remaining);
+    } else {
+      pixel_weights.RemoveLastWeightAndAdjust(remaining);
     }
   }
   return true;
diff --git a/core/fxge/dib/cstretchengine.h b/core/fxge/dib/cstretchengine.h
index eef7fd0..da5792e 100644
--- a/core/fxge/dib/cstretchengine.h
+++ b/core/fxge/dib/cstretchengine.h
@@ -26,6 +26,10 @@
   static constexpr uint32_t kFixedPointBits = 16;
   static constexpr uint32_t kFixedPointOne = 1 << kFixedPointBits;
 
+  static inline uint32_t FixedFromDouble(double d) {
+    return static_cast<uint32_t>(FXSYS_round(d * kFixedPointOne));
+  }
+
   static inline uint32_t FixedFromFloat(float f) {
     return static_cast<uint32_t>(FXSYS_roundf(f * kFixedPointOne));
   }
@@ -55,9 +59,12 @@
       m_Weights[position - m_SrcStart] = weight;
     }
 
-    void RemoveLastWeight() {
+    // NOTE: relies on defined behaviour for unsigned overflow to
+    // decrement the previous position, as needed.
+    void RemoveLastWeightAndAdjust(uint32_t weight_change) {
       CHECK_GT(m_SrcEnd, m_SrcStart);
       --m_SrcEnd;
+      m_Weights[m_SrcEnd - m_SrcStart] += weight_change;
     }
 
     int m_SrcStart;
diff --git a/core/fxge/dib/cstretchengine_unittest.cpp b/core/fxge/dib/cstretchengine_unittest.cpp
index 888a3d9..379d844 100644
--- a/core/fxge/dib/cstretchengine_unittest.cpp
+++ b/core/fxge/dib/cstretchengine_unittest.cpp
@@ -86,8 +86,7 @@
   EXPECT_FALSE(engine.GetResampleOptionsForTest().bLossy);
 }
 
-// See https://crbug.com/pdfium/1688
-TEST(CStretchEngine, DISABLED_WeightRounding) {
+TEST(CStretchEngine, WeightRounding) {
   FXDIB_ResampleOptions options;
   ExecuteStretchTests(options);
 }
@@ -98,8 +97,7 @@
   ExecuteStretchTests(options);
 }
 
-// See https://crbug.com/pdfium/1688
-TEST(CStretchEngine, DISABLED_WeightRoundingBilinear) {
+TEST(CStretchEngine, WeightRoundingBilinear) {
   FXDIB_ResampleOptions options;
   options.bInterpolateBilinear = true;
   ExecuteStretchTests(options);
diff --git a/fpdfsdk/fpdf_edit_embeddertest.cpp b/fpdfsdk/fpdf_edit_embeddertest.cpp
index 6077395..7ac8ed6 100644
--- a/fpdfsdk/fpdf_edit_embeddertest.cpp
+++ b/fpdfsdk/fpdf_edit_embeddertest.cpp
@@ -3671,7 +3671,7 @@
     ScopedFPDFBitmap bitmap(
         FPDFImageObj_GetRenderedBitmap(document(), page, obj));
     EXPECT_EQ(FPDFBitmap_BGRA, FPDFBitmap_GetFormat(bitmap.get()));
-    CompareBitmap(bitmap.get(), 53, 43, "90fa16c2fb2bf8ad3654c2258417664c");
+    CompareBitmap(bitmap.get(), 53, 43, "582ca300e003f512d7b552c7b5b45d2e");
   }
 
   // Check the matrix for |obj|.
@@ -3708,7 +3708,7 @@
     ScopedFPDFBitmap bitmap(
         FPDFImageObj_GetRenderedBitmap(document(), page, obj));
     EXPECT_EQ(FPDFBitmap_BGRA, FPDFBitmap_GetFormat(bitmap.get()));
-    CompareBitmap(bitmap.get(), 120, 43, "57ed8e15daa535490ff0c8b7640a36b4");
+    CompareBitmap(bitmap.get(), 120, 43, "0824c16dcf2dfcef44b45d88db1fddce");
   }
 
   UnloadPage(page);
diff --git a/testing/resources/pixel/bug_591137_expected.pdf.0.png b/testing/resources/pixel/bug_591137_expected.pdf.0.png
index 265e682..74c5c64 100644
--- a/testing/resources/pixel/bug_591137_expected.pdf.0.png
+++ b/testing/resources/pixel/bug_591137_expected.pdf.0.png
Binary files differ
diff --git a/testing/resources/pixel/type3_expected.pdf.0.png b/testing/resources/pixel/type3_expected.pdf.0.png
index 6837bb8..63d9e57 100644
--- a/testing/resources/pixel/type3_expected.pdf.0.png
+++ b/testing/resources/pixel/type3_expected.pdf.0.png
Binary files differ
diff --git a/testing/resources/pixel/xfa_specific/resolve_nodes_0_expected.pdf.0.png b/testing/resources/pixel/xfa_specific/resolve_nodes_0_expected.pdf.0.png
index 72c2e2a..adfabbc 100644
--- a/testing/resources/pixel/xfa_specific/resolve_nodes_0_expected.pdf.0.png
+++ b/testing/resources/pixel/xfa_specific/resolve_nodes_0_expected.pdf.0.png
Binary files differ