diff --git a/modules/imgcodecs/src/grfmt_bmp.cpp b/modules/imgcodecs/src/grfmt_bmp.cpp
index 4540d3cd93..77201b3af1 100644
--- a/modules/imgcodecs/src/grfmt_bmp.cpp
+++ b/modules/imgcodecs/src/grfmt_bmp.cpp
@@ -337,7 +337,7 @@ bool  BmpDecoder::readData( Mat& img )
                     }
                     else
                     {
-                        int x_shift3 = (int)(line_end - data);
+                        ptrdiff_t x_shift3 = line_end - data;
 
                         if( code == 2 )
                         {
@@ -430,7 +430,7 @@ decode_rle4_bad: ;
                     }
                     else
                     {
-                        int x_shift3 = (int)(line_end - data);
+                        ptrdiff_t x_shift3 = line_end - data;
                         int y_shift = m_height - y;
 
                         if( code || !line_end_flag || x_shift3 < width3 )
@@ -441,7 +441,7 @@ decode_rle4_bad: ;
                                 y_shift = m_strm.getByte();
                             }
 
-                            x_shift3 += (y_shift * width3) & ((code == 0) - 1);
+                            x_shift3 += ((ptrdiff_t)y_shift * width3) & ((code == 0) - 1);
 
                             if( y >= m_height )
                                 break;
diff --git a/modules/imgcodecs/src/utils.cpp b/modules/imgcodecs/src/utils.cpp
index 41fd9f5041..3b597fe61c 100644
--- a/modules/imgcodecs/src/utils.cpp
+++ b/modules/imgcodecs/src/utils.cpp
@@ -435,7 +435,7 @@ bool  IsColorPalette( PaletteEntry* palette, int bpp )
 uchar* FillUniColor( uchar* data, uchar*& line_end,
                      int step, int width3,
                      int& y, int height,
-                     int count3, PaletteEntry clr )
+                     ptrdiff_t count3, PaletteEntry clr )
 {
     do
     {
@@ -444,7 +444,7 @@ uchar* FillUniColor( uchar* data, uchar*& line_end,
         if( end > line_end )
             end = line_end;
 
-        count3 -= (int)(end - data);
+        count3 -= end - data;
 
         for( ; data < end; data += 3 )
         {
@@ -467,7 +467,7 @@ uchar* FillUniColor( uchar* data, uchar*& line_end,
 uchar* FillUniGray( uchar* data, uchar*& line_end,
                     int step, int width,
                     int& y, int height,
-                    int count, uchar clr )
+                    ptrdiff_t count, uchar clr )
 {
     do
     {
@@ -476,7 +476,7 @@ uchar* FillUniGray( uchar* data, uchar*& line_end,
         if( end > line_end )
             end = line_end;
 
-        count -= (int)(end - data);
+        count -= end - data;
 
         for( ; data < end; data++ )
         {
diff --git a/modules/imgcodecs/src/utils.hpp b/modules/imgcodecs/src/utils.hpp
index 95deebde31..8b0ad1a9e9 100644
--- a/modules/imgcodecs/src/utils.hpp
+++ b/modules/imgcodecs/src/utils.hpp
@@ -124,9 +124,9 @@ void  FillGrayPalette( PaletteEntry* palette, int bpp, bool negative = false );
 bool  IsColorPalette( PaletteEntry* palette, int bpp );
 void  CvtPaletteToGray( const PaletteEntry* palette, uchar* grayPalette, int entries );
 uchar* FillUniColor( uchar* data, uchar*& line_end, int step, int width3,
-                     int& y, int height, int count3, PaletteEntry clr );
+                     int& y, int height, ptrdiff_t count3, PaletteEntry clr );
 uchar* FillUniGray( uchar* data, uchar*& line_end, int step, int width3,
-                     int& y, int height, int count3, uchar clr );
+                     int& y, int height, ptrdiff_t count3, uchar clr );
 
 uchar* FillColorRow8( uchar* data, uchar* indices, int len, PaletteEntry* palette );
 uchar* FillGrayRow8( uchar* data, uchar* indices, int len, uchar* palette );