skip persumed AUs that don't have any VCL NALus (#62)

* skip persumed AUs that don't have any VCL NALus

* add typespec

* forward_au? -> should_forward_au

* bump version

README.md

@@ -22,7 +22,7 @@ The package can be installed by adding `membrane_h26x_plugin` to your list of de
 ```elixir
 def deps do
  [
- {:membrane_h26x_plugin, "~> 0.10.1"}
+ {:membrane_h26x_plugin, "~> 0.10.2"}
  ]
 end
 ```

lib/membrane_h264_plugin/h26x_parser.ex

@@ -354,18 +354,15 @@ defmodule Membrane.H26x.Parser do
 
  @spec prepare_actions_for_au(AUSplitter.access_unit(), boolean(), state()) :: callback_return()
  def prepare_actions_for_au(au, keyframe?, state) do
- {{pts, dts}, state} = prepare_timestamps(au, state)
- {should_skip_au, state} = skip_au?(au, keyframe?, state)
+ {should_forward_au, state} = should_forward_au(au, keyframe?, state)
 
- buffers_actions =
- if should_skip_au do
- []
- else
- buffers = wrap_into_buffer(au, pts, dts, keyframe?, state)
- [buffer: {:output, buffers}]
- end
-
- {buffers_actions, state}
+ if should_forward_au do
+ {{pts, dts}, state} = prepare_timestamps(au, state)
+ buffers = wrap_into_buffer(au, pts, dts, keyframe?, state)
+ {[buffer: {:output, buffers}], state}
+ else
+ {[], state}
+ end
  end
 
  @spec flatten_parameter_sets(parameter_sets()) :: list()
@@ -407,28 +404,33 @@ defmodule Membrane.H26x.Parser do
 
  {timestamps, %{state | au_timestamp_generator: timestamp_generator}}
  else
- case state.nalu_parser_mod do
- Membrane.H264.NALuParser ->
- require Membrane.H264.NALuTypes, as: NALuTypes
- {Enum.find(au, &NALuTypes.is_vcl_nalu_type(&1.type)).timestamps, state}
-
- Membrane.H265.NALuParser ->
- require Membrane.H265.NALuTypes, as: NALuTypes
- {Enum.find(au, &NALuTypes.is_vcl_nalu_type(&1.type)).timestamps, state}
- end
+ {first_vcl_nalu(au, state).timestamps, state}
  end
  end
 
- @spec skip_au?(AUSplitter.access_unit(), boolean(), state()) :: {boolean(), state()}
- defp skip_au?(au, keyframe?, state) do
- has_seen_keyframe? = keyframe? and Enum.all?(au, &(&1.status == :valid))
+ @spec should_forward_au(AUSplitter.access_unit(), boolean(), state()) :: {boolean(), state()}
+ defp should_forward_au(au, keyframe?, state) do
+ with true <- Enum.all?(au, &(&1.status == :valid)),
+ true <- first_vcl_nalu(au, state) != nil do
+ skip_until_keyframe? = state.skip_until_keyframe and not keyframe?
+ state = %{state | skip_until_keyframe: skip_until_keyframe?}
+ {not skip_until_keyframe?, state}
+ else
+ false -> {false, state}
+ end
+ end
 
- state = %{
- state
- | skip_until_keyframe: state.skip_until_keyframe and not has_seen_keyframe?
- }
+ @spec first_vcl_nalu(AUSplitter.access_unit(), state()) :: Membrane.H26x.NALu.t()
+ defp first_vcl_nalu(au, state) do
+ case state.nalu_parser_mod do
+ Membrane.H264.NALuParser ->
+ require Membrane.H264.NALuTypes, as: NALuTypes
+ Enum.find(au, &NALuTypes.is_vcl_nalu_type(&1.type))
 
- {Enum.any?(au, &(&1.status == :error)) or state.skip_until_keyframe, state}
+ Membrane.H265.NALuParser ->
+ require Membrane.H265.NALuTypes, as: NALuTypes
+ Enum.find(au, &NALuTypes.is_vcl_nalu_type(&1.type))
+ end
  end
 
  @spec wrap_into_buffer(

mix.exs

@@ -1,7 +1,7 @@
 defmodule Membrane.H26x.Plugin.Mixfile do
  use Mix.Project
 
- @version "0.10.1"
+ @version "0.10.2"
  @github_url "https://github.com/membraneframework/membrane_h26x_plugin"
 
  def project do