message: Fix a potential multiplication bug
diff: @@ -534,7 +534,7 @@ where
  Rows {
  chunks: self
  .data
  - .chunks((<P as Pixel>::channel_count() as u32 * self.width) as usize),
  + .chunks(<P as Pixel>::channel_count() as usize * self.width as usize),
  }
  }
  @@ -665,7 +665,7 @@ where
  RowsMut {
  chunks: self
  .data
  - .chunks_mut((<P as Pixel>::channel_count() as u32 * self.width) as usize),
  + .chunks_mut(<P as Pixel>::channel_count() as usize * self.width as usize),
  }
  }
  