/// <returns>Returns the old pixel data thats has gust been replaced.</returns>
/// <returns>Returns the old pixel data thats has gust been replaced.</returns>
/// <remarks>If <see cref="M:PixelAccessor.PooledMemory"/> is true then caller is responsible for ensuring <see cref="M:PixelDataPool.Return()"/> is called.</remarks>
/// <remarks>If <see cref="M:PixelAccessor.PooledMemory"/> is true then caller is responsible for ensuring <see cref="M:PixelDataPool.Return()"/> is called.</remarks>