defmodule Membrane.Realtimer do
@moduledoc """
Sends buffers to the output in real time, according to buffers' timestamps.
If buffers come in slower than realtime, they're sent as they come in.
"""
use Membrane.Filter
alias Membrane.Buffer
def_input_pad :input, caps: :any, demand_unit: :buffers
def_output_pad :output, caps: :any, mode: :push
@impl true
def handle_init(_opts) do
{:ok, %{previous_timestamp: 0, tick_actions: []}}
end
@impl true
def handle_prepared_to_playing(_ctx, state) do
{{:ok, start_timer: {:timer, :no_interval}, demand: {:input, 1}}, state}
end
@impl true
def handle_process(:input, buffer, _ctx, state) do
use Ratio
interval = Buffer.get_dts_or_pts(buffer) - state.previous_timestamp
state = %{
state
| previous_timestamp: Buffer.get_dts_or_pts(buffer),
tick_actions: [buffer: {:output, buffer}] ++ state.tick_actions
}
{{:ok, timer_interval: {:timer, interval}}, state}
end
@impl true
def handle_event(pad, event, _ctx, %{tick_actions: tick_actions} = state)
when pad == :output or tick_actions == [] do
{{:ok, forward: event}, state}
end
@impl true
def handle_event(:input, event, _ctx, state) do
{:ok, %{state | tick_actions: [event: {:output, event}] ++ state.tick_actions}}
end
@impl true
def handle_caps(:input, caps, _ctx, %{tick_actions: []} = state) do
{{:ok, forward: caps}, state}
end
@impl true
def handle_caps(:input, caps, _ctx, state) do
{:ok, %{state | tick_actions: [caps: {:output, caps}] ++ state.tick_actions}}
end
@impl true
def handle_end_of_stream(:input, _ctx, %{tick_actions: []} = state) do
{{:ok, end_of_stream: :output}, state}
end
@impl true
def handle_end_of_stream(:input, _ctx, state) do
{:ok, %{state | tick_actions: [end_of_stream: :output] ++ state.tick_actions}}
end
@impl true
def handle_tick(:timer, _ctx, state) do
actions =
[timer_interval: {:timer, :no_interval}] ++
Enum.reverse(state.tick_actions) ++ [demand: {:input, 1}]
{{:ok, actions}, %{state | tick_actions: []}}
end
@impl true
def handle_playing_to_prepared(_ctx, state) do
{{:ok, stop_timer: :timer}, %{state | previous_timestamp: 0}}
end
end