diff --git a/fpdfsdk/fpdf_edit_embeddertest.cpp b/fpdfsdk/fpdf_edit_embeddertest.cpp
index 800fc70..e47f3db 100644
--- a/fpdfsdk/fpdf_edit_embeddertest.cpp
+++ b/fpdfsdk/fpdf_edit_embeddertest.cpp
@@ -2175,11 +2175,17 @@
   // Add parameters:
   // - int "IntKey" : 42
   // - string "StringKey": "StringValue"
+  // - blob "BlobKey": "\x01\x02\x03\0BlobValue1\0\0\0BlobValue2\0"
+  constexpr const size_t kBlobLen = 28;
+  char kBlobValue[kBlobLen];
+  memcpy(kBlobValue, "\x01\x02\x03\0BlobValue1\0\0\0BlobValue2\0", kBlobLen);
   EXPECT_EQ(0, FPDFPageObjMark_CountParams(mark));
   EXPECT_TRUE(FPDFPageObjMark_SetIntParam(document(), mark, "IntKey", 42));
   EXPECT_TRUE(FPDFPageObjMark_SetStringParam(document(), mark, "StringKey",
                                              "StringValue"));
-  EXPECT_EQ(2, FPDFPageObjMark_CountParams(mark));
+  EXPECT_TRUE(FPDFPageObjMark_SetBlobParam(document(), mark, "BlobKey",
+                                           kBlobValue, kBlobLen));
+  EXPECT_EQ(3, FPDFPageObjMark_CountParams(mark));
 
   // Check the two parameters can be retrieved.
   EXPECT_EQ(FPDF_OBJECT_NUMBER,
@@ -2197,6 +2203,14 @@
   name = GetPlatformWString(reinterpret_cast<unsigned short*>(buffer));
   EXPECT_EQ(L"StringValue", name);
 
+  EXPECT_EQ(FPDF_OBJECT_STRING,
+            FPDFPageObjMark_GetParamValueType(mark, "BlobKey"));
+  out_buffer_len = 0;
+  EXPECT_TRUE(FPDFPageObjMark_GetParamBlobValue(mark, "BlobKey", buffer, 256,
+                                                &out_buffer_len));
+  EXPECT_EQ(kBlobLen, out_buffer_len);
+  EXPECT_EQ(0, memcmp(kBlobValue, buffer, kBlobLen));
+
 // Render and check the bitmap is the expected one.
 #if _FX_PLATFORM_ == _FX_PLATFORM_APPLE_
   const char md5[] = "17d2b6cd574cf66170b09c8927529a94";
diff --git a/fpdfsdk/fpdf_editpage.cpp b/fpdfsdk/fpdf_editpage.cpp
index 4df5505..02c07d1 100644
--- a/fpdfsdk/fpdf_editpage.cpp
+++ b/fpdfsdk/fpdf_editpage.cpp
@@ -402,6 +402,9 @@
                                     void* buffer,
                                     unsigned long buflen,
                                     unsigned long* out_buflen) {
+  if (!out_buflen)
+    return false;
+
   const CPDF_Dictionary* pParams = GetMarkParamDict(mark);
   if (!pParams)
     return false;
@@ -416,6 +419,33 @@
 }
 
 FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
+FPDFPageObjMark_GetParamBlobValue(FPDF_PAGEOBJECTMARK mark,
+                                  FPDF_BYTESTRING key,
+                                  void* buffer,
+                                  unsigned long buflen,
+                                  unsigned long* out_buflen) {
+  if (!out_buflen)
+    return false;
+
+  const CPDF_Dictionary* pParams = GetMarkParamDict(mark);
+  if (!pParams)
+    return false;
+
+  const CPDF_Object* pObj = pParams->GetObjectFor(key);
+  if (!pObj || !pObj->IsString())
+    return false;
+
+  ByteString result = pObj->GetString();
+  unsigned long len = result.GetLength();
+
+  if (buffer && len <= buflen)
+    memcpy(buffer, result.c_str(), len);
+
+  *out_buflen = len;
+  return true;
+}
+
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
 FPDFPageObj_HasTransparency(FPDF_PAGEOBJECT pageObject) {
   if (!pageObject)
     return false;
@@ -475,6 +505,24 @@
   return true;
 }
 
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
+FPDFPageObjMark_SetBlobParam(FPDF_DOCUMENT document,
+                             FPDF_PAGEOBJECTMARK mark,
+                             FPDF_BYTESTRING key,
+                             void* value,
+                             unsigned long value_len) {
+  CPDF_Dictionary* pParams = GetOrCreateMarkParamsDict(document, mark);
+  if (!pParams)
+    return false;
+
+  if (!value && value_len > 0)
+    return false;
+
+  pParams->SetNewFor<CPDF_String>(
+      key, ByteString(static_cast<const char*>(value), value_len), true);
+  return true;
+}
+
 FPDF_EXPORT int FPDF_CALLCONV FPDFPageObj_GetType(FPDF_PAGEOBJECT pageObject) {
   if (!pageObject)
     return FPDF_PAGEOBJ_UNKNOWN;
diff --git a/fpdfsdk/fpdf_view_c_api_test.c b/fpdfsdk/fpdf_view_c_api_test.c
index 70db94f..a89bc2e 100644
--- a/fpdfsdk/fpdf_view_c_api_test.c
+++ b/fpdfsdk/fpdf_view_c_api_test.c
@@ -139,10 +139,12 @@
     CHK(FPDFImageObj_SetMatrix);
     CHK(FPDFPageObjMark_CountParams);
     CHK(FPDFPageObjMark_GetName);
+    CHK(FPDFPageObjMark_GetParamBlobValue);
     CHK(FPDFPageObjMark_GetParamIntValue);
     CHK(FPDFPageObjMark_GetParamKey);
     CHK(FPDFPageObjMark_GetParamStringValue);
     CHK(FPDFPageObjMark_GetParamValueType);
+    CHK(FPDFPageObjMark_SetBlobParam);
     CHK(FPDFPageObjMark_SetIntParam);
     CHK(FPDFPageObjMark_SetStringParam);
     CHK(FPDFPageObj_AddMark);
diff --git a/public/fpdf_edit.h b/public/fpdf_edit.h
index e7f6cc4..677bce8 100644
--- a/public/fpdf_edit.h
+++ b/public/fpdf_edit.h
@@ -407,7 +407,7 @@
 //   out_buflen - pointer to variable that will receive the length of the value.
 //                Not filled if false is returned.
 //
-// Returns TRUE if the key maps to a string value, FALSE otherwise.
+// Returns TRUE if the key maps to a string/blob value, FALSE otherwise.
 FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
 FPDFPageObjMark_GetParamStringValue(FPDF_PAGEOBJECTMARK mark,
                                     FPDF_BYTESTRING key,
@@ -416,6 +416,26 @@
                                     unsigned long* out_buflen);
 
 // Experimental API.
+// Get the value of a blob property in a content mark by key.
+// |buffer| is only modified if |buflen| is longer than or equal to the length
+// of the value.
+//
+//   mark       - handle to a content mark.
+//   key        - string key of the property.
+//   buffer     - buffer for holding the returned value.
+//   buflen     - length of the buffer.
+//   out_buflen - pointer to variable that will receive the length of the value.
+//                Not filled if false is returned.
+//
+// Returns TRUE if the key maps to a string/blob value, FALSE otherwise.
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
+FPDFPageObjMark_GetParamBlobValue(FPDF_PAGEOBJECTMARK mark,
+                                  FPDF_BYTESTRING key,
+                                  void* buffer,
+                                  unsigned long buflen,
+                                  unsigned long* out_buflen);
+
+// Experimental API.
 // Set the value of an int property in a content mark by key. If a parameter
 // with key |key| exists, its value is set to |value|. Otherwise, it is added as
 // a new parameter.
@@ -449,6 +469,25 @@
                                FPDF_BYTESTRING key,
                                FPDF_BYTESTRING value);
 
+// Experimental API.
+// Set the value of a blob property in a content mark by key. If a parameter
+// with key |key| exists, its value is set to |value|. Otherwise, it is added as
+// a new parameter.
+//
+//   document  - handle to the document.
+//   mark      - handle to a content mark.
+//   key       - string key of the property.
+//   value     - pointer to blob value to set.
+//   value_len - size in bytes of |value|.
+//
+// Returns TRUE if the operation succeeded, FALSE otherwise.
+FPDF_EXPORT FPDF_BOOL FPDF_CALLCONV
+FPDFPageObjMark_SetBlobParam(FPDF_DOCUMENT document,
+                             FPDF_PAGEOBJECTMARK mark,
+                             FPDF_BYTESTRING key,
+                             void* value,
+                             unsigned long value_len);
+
 // Load an image from a JPEG image file and then set it into |image_object|.
 //
 //   pages        - pointer to the start of all loaded pages, may be NULL.