diff --git a/src/format/chapter/chapter.rs b/src/format/chapter/chapter.rs
index 1b56b37..05fb23c 100644
--- a/src/format/chapter/chapter.rs
+++ b/src/format/chapter/chapter.rs
@@ -16,9 +16,7 @@ impl<'a> Chapter<'a> {
     }
 
     pub unsafe fn as_ptr(&self) -> *const AVChapter {
-        *(*self.context.as_ptr())
-            .chapters
-            .offset(self.index as isize)
+        *(*self.context.as_ptr()).chapters.add(self.index)
     }
 }
 
diff --git a/src/format/chapter/chapter_mut.rs b/src/format/chapter/chapter_mut.rs
index 5f9d7f5..6cc111a 100644
--- a/src/format/chapter/chapter_mut.rs
+++ b/src/format/chapter/chapter_mut.rs
@@ -26,9 +26,7 @@ impl<'a> ChapterMut<'a> {
     }
 
     pub unsafe fn as_mut_ptr(&mut self) -> *mut AVChapter {
-        *(*self.context.as_mut_ptr())
-            .chapters
-            .offset(self.index as isize)
+        *(*self.context.as_mut_ptr()).chapters.add(self.index)
     }
 }
 
diff --git a/src/format/stream/stream.rs b/src/format/stream/stream.rs
index 0ddac24..f7c2e0e 100644
--- a/src/format/stream/stream.rs
+++ b/src/format/stream/stream.rs
@@ -16,7 +16,7 @@ impl<'a> Stream<'a> {
     }
 
     pub unsafe fn as_ptr(&self) -> *const AVStream {
-        *(*self.context.as_ptr()).streams.offset(self.index as isize)
+        *(*self.context.as_ptr()).streams.add(self.index)
     }
 }
 
diff --git a/src/format/stream/stream_mut.rs b/src/format/stream/stream_mut.rs
index 5e69376..1520a80 100644
--- a/src/format/stream/stream_mut.rs
+++ b/src/format/stream/stream_mut.rs
@@ -24,9 +24,7 @@ impl<'a> StreamMut<'a> {
     }
 
     pub unsafe fn as_mut_ptr(&mut self) -> *mut AVStream {
-        *(*self.context.as_mut_ptr())
-            .streams
-            .offset(self.index as isize)
+        *(*self.context.as_mut_ptr()).streams.add(self.index)
     }
 }
 
diff --git a/src/util/format/sample.rs b/src/util/format/sample.rs
index 901b8c4..fda106c 100644
--- a/src/util/format/sample.rs
+++ b/src/util/format/sample.rs
@@ -185,7 +185,7 @@ impl Index<usize> for Buffer {
             panic!("out of bounds");
         }
 
-        unsafe { slice::from_raw_parts(*self.buffer.offset(index as isize), self.size as usize) }
+        unsafe { slice::from_raw_parts(*self.buffer.add(index), self.size as usize) }
     }
 }