+
+ def get_content_type(file) do
+ match = File.open(file, [:read], fn(f) ->
+ case IO.binread(f, 8) do
+ <<0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a>> ->
+ "image/png"
+ <<0x47, 0x49, 0x46, 0x38, _, 0x61, _, _>> ->
+ "image/gif"
+ <<0xff, 0xd8, 0xff, _, _, _, _, _>> ->
+ "image/jpeg"
+ <<0x1a, 0x45, 0xdf, 0xa3, _, _, _, _>> ->
+ "video/webm"
+ <<0x00, 0x00, 0x00, _, 0x66, 0x74, 0x79, 0x70>> ->
+ "video/mp4"
+ <<0x49, 0x44, 0x33, _, _, _, _, _>> ->
+ "audio/mpeg"
+ <<0x4f, 0x67, 0x67, 0x53, 0x00, 0x02, 0x00, 0x00>> ->
+ "audio/ogg"
+ <<0x52, 0x49, 0x46, 0x46, _, _, _, _>> ->
+ "audio/wav"
+ _ ->
+ "application/octet-stream"
+ end
+ end)
+
+ case match do
+ {:ok, type} -> type
+ _e -> "application/octet-stream"
+ end
+ end