diff --git a/modules/imgcodecs/src/bitstrm.cpp b/modules/imgcodecs/src/bitstrm.cpp
index 80bb26c097..a11697264b 100644
--- a/modules/imgcodecs/src/bitstrm.cpp
+++ b/modules/imgcodecs/src/bitstrm.cpp
@@ -42,6 +42,7 @@
 
 #include "precomp.hpp"
 #include "bitstrm.hpp"
+#include "utils.hpp"
 
 namespace cv
 {
@@ -165,7 +166,7 @@ void  RBaseStream::release()
 
 void  RBaseStream::setPos( int pos )
 {
-    assert( isOpened() && pos >= 0 );
+    CV_Assert(isOpened() && pos >= 0);
 
     if( !m_file )
     {
@@ -182,14 +183,19 @@ void  RBaseStream::setPos( int pos )
 
 int  RBaseStream::getPos()
 {
-    assert( isOpened() );
-    return m_block_pos + (int)(m_current - m_start);
+    CV_Assert(isOpened());
+    int pos = validateToInt((m_current - m_start) + m_block_pos);
+    CV_Assert(pos >= m_block_pos); // overflow check
+    CV_Assert(pos >= 0); // overflow check
+    return pos;
 }
 
 void  RBaseStream::skip( int bytes )
 {
-    assert( bytes >= 0 );
+    CV_Assert(bytes >= 0);
+    uchar* old = m_current;
     m_current += bytes;
+    CV_Assert(m_current >= old);  // overflow check
 }
 
 /////////////////////////  RLByteStream ////////////////////////////
@@ -221,7 +227,7 @@ int RLByteStream::getBytes( void* buffer, int count )
 {
     uchar*  data = (uchar*)buffer;
     int readed = 0;
-    assert( count >= 0 );
+    CV_Assert(count >= 0);
 
     while( count > 0 )
     {
@@ -373,7 +379,7 @@ void  WBaseStream::writeBlock()
 {
     int size = (int)(m_current - m_start);
 
-    assert( isOpened() );
+    CV_Assert(isOpened());
     if( size == 0 )
         return;
 
@@ -444,7 +450,7 @@ void  WBaseStream::release()
 
 int  WBaseStream::getPos()
 {
-    assert( isOpened() );
+    CV_Assert(isOpened());
     return m_block_pos + (int)(m_current - m_start);
 }
 
@@ -467,7 +473,7 @@ void WLByteStream::putBytes( const void* buffer, int count )
 {
     uchar* data = (uchar*)buffer;
 
-    assert( data && m_current && count >= 0 );
+    CV_Assert(data && m_current && count >= 0);
 
     while( count )
     {
diff --git a/modules/imgcodecs/src/grfmt_bmp.cpp b/modules/imgcodecs/src/grfmt_bmp.cpp
index ab46219aa0..25a386eaeb 100644
--- a/modules/imgcodecs/src/grfmt_bmp.cpp
+++ b/modules/imgcodecs/src/grfmt_bmp.cpp
@@ -95,6 +95,7 @@ bool  BmpDecoder::readHeader()
         m_offset = m_strm.getDWord();
 
         int  size = m_strm.getDWord();
+        CV_Assert(size > 0); // overflow, 2Gb limit
 
         if( size >= 36 )
         {
diff --git a/modules/imgcodecs/src/grfmt_pam.cpp b/modules/imgcodecs/src/grfmt_pam.cpp
index 3dd4605588..5eeaed1ec6 100644
--- a/modules/imgcodecs/src/grfmt_pam.cpp
+++ b/modules/imgcodecs/src/grfmt_pam.cpp
@@ -53,6 +53,8 @@
 #include "utils.hpp"
 #include "grfmt_pam.hpp"
 
+using namespace cv;
+
 /* the PAM related fields */
 #define MAX_PAM_HEADER_IDENITFIER_LENGTH 8
 #define MAX_PAM_HEADER_VALUE_LENGTH 255
@@ -184,7 +186,7 @@ basic_conversion (void *src, const struct channel_layout *layout, int src_sampe_
                     }
                     break;
                 default:
-                    assert (0);
+                    CV_Error(Error::StsInternal, "");
             }
             break;
         }
@@ -205,12 +207,12 @@ basic_conversion (void *src, const struct channel_layout *layout, int src_sampe_
                     }
                     break;
                 default:
-                    assert (0);
+                    CV_Error(Error::StsInternal, "");
             }
             break;
         }
         default:
-            assert (0);
+            CV_Error(Error::StsInternal, "");
     }
 }
 
@@ -711,7 +713,7 @@ bool PAMEncoder::write( const Mat& img, const std::vector<int>& params )
         } else
             strm.putBytes( data, stride*height );
     } else
-        assert (0);
+        CV_Error(Error::StsInternal, "");
 
     strm.close();
     return true;
diff --git a/modules/imgcodecs/src/grfmt_sunras.cpp b/modules/imgcodecs/src/grfmt_sunras.cpp
index 77efc4b1bf..85a9ab9d34 100644
--- a/modules/imgcodecs/src/grfmt_sunras.cpp
+++ b/modules/imgcodecs/src/grfmt_sunras.cpp
@@ -124,7 +124,7 @@ bool  SunRasterDecoder::readHeader()
                     m_type = IsColorPalette( m_palette, m_bpp ) ? CV_8UC3 : CV_8UC1;
                     m_offset = m_strm.getPos();
 
-                    assert( m_offset == 32 + m_maplength );
+                    CV_Assert(m_offset == 32 + m_maplength);
                     result = true;
                 }
             }
@@ -137,7 +137,7 @@ bool  SunRasterDecoder::readHeader()
 
                 m_offset = m_strm.getPos();
 
-                assert( m_offset == 32 + m_maplength );
+                CV_Assert(m_offset == 32 + m_maplength);
                 result = true;
             }
         }
@@ -230,7 +230,7 @@ bool  SunRasterDecoder::readData( Mat& img )
                         code = m_strm.getByte();
                         if( len > line_end - tsrc )
                         {
-                            assert(0);
+                            CV_Error(Error::StsInternal, "");
                             goto bad_decoding_1bpp;
                         }
 
@@ -371,7 +371,7 @@ bad_decoding_end:
             result = true;
             break;
         default:
-            assert(0);
+            CV_Error(Error::StsInternal, "");
         }
     }
     CV_CATCH_ALL
diff --git a/modules/imgcodecs/src/precomp.hpp b/modules/imgcodecs/src/precomp.hpp
index d5ce248498..c280b08ce2 100644
--- a/modules/imgcodecs/src/precomp.hpp
+++ b/modules/imgcodecs/src/precomp.hpp
@@ -56,7 +56,6 @@
 #include <string.h>
 #include <limits.h>
 #include <ctype.h>
-#include <assert.h>
 
 #if defined _WIN32 || defined WINCE
     #include <windows.h>
diff --git a/modules/imgcodecs/src/utils.cpp b/modules/imgcodecs/src/utils.cpp
index 474dae008c..3273912289 100644
--- a/modules/imgcodecs/src/utils.cpp
+++ b/modules/imgcodecs/src/utils.cpp
@@ -670,7 +670,7 @@ cvConvertImage( const CvArr* srcarr, CvArr* dstarr, int flags )
             icvCvt_BGR2Gray_8u_C3C1R( s, s_step, d, d_step, size, swap_rb );
             break;
         case 33:
-            assert( swap_rb );
+            CV_Assert(swap_rb);
             icvCvt_RGB2BGR_8u_C3R( s, s_step, d, d_step, size );
             break;
         case 41: