add filter

Author: mat-hek

.formatter.exs

@@ -1,4 +1,5 @@
 # Used by "mix format"
 [
-  inputs: ["{mix,.formatter,bundlex}.exs", "{config,lib,test}/**/*.{ex,exs}"]
+  inputs: ["{mix,.formatter,bundlex}.exs", "{config,lib,test}/**/*.{ex,exs}"],
+  import_deps: [:membrane_core]
 ]

lib/turbojpeg/filter.ex

@@ -0,0 +1,38 @@
+defmodule Turbojpeg.Filter do
+  use Membrane.Filter
+  alias Membrane.Buffer
+
+  def_input_pad :input, demand_unit: :buffers, caps: Membrane.Caps.Video.Raw
+  def_output_pad :output, caps: Membrane.Caps.Video.Raw
+
+  def_options quality: [
+                type: :integer,
+                spec: Turbojpeg.quality(),
+                default: 80,
+                description: "Jpeg encoding quality"
+              ]
+
+  @impl true
+  def handle_demand(:output, size, :buffers, _ctx, state) do
+    {{:ok, demand: {:input, size}}, state}
+  end
+
+  @impl true
+  def handle_process(:input, buffer, ctx, state) do
+    %{caps: caps} = ctx.pads.input
+
+    with {:ok, payload} <-
+           Turbojpeg.yuv_to_jpeg(
+             buffer.payload,
+             caps.width,
+             caps.height,
+             state.quality,
+             caps.format
+           ) do
+      buffer = %Buffer{buffer | payload: payload}
+      {{:ok, buffer: {:output, buffer}}, state}
+    else
+      {:error, _} = error -> {error, state}
+    end
+  end
+end

lib/turbojpeg/sink.ex

@@ -3,12 +3,10 @@ defmodule Turbojpeg.Sink do
   alias Membrane.{Buffer, Time}
   alias Membrane.Caps.Video.Raw
 
-  def_input_pad(:input, caps: Raw, demand_unit: :buffers)
+  def_input_pad :input, caps: Raw, demand_unit: :buffers
 
-  def_options(
-    filename: [type: :binary, description: "File to write the jpeg file"],
-    quality: [type: :integer, description: "Jpeg encoding quality"]
-  )
+  def_options filename: [type: :binary, description: "File to write the jpeg file"],
+              quality: [type: :integer, description: "Jpeg encoding quality"]
 
   @impl true
   def handle_init(options) do