|
- # Pleroma: A lightweight social networking server
- # Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
- # SPDX-License-Identifier: AGPL-3.0-only
-
- defmodule Pleroma.Helpers.MediaHelper do
- @moduledoc """
- Handles common media-related operations.
- """
-
- alias Pleroma.HTTP
-
- require Logger
-
- def missing_dependencies do
- Enum.reduce([imagemagick: "convert", ffmpeg: "ffmpeg"], [], fn {sym, executable}, acc ->
- if Pleroma.Utils.command_available?(executable) do
- acc
- else
- [sym | acc]
- end
- end)
- end
-
- def image_resize(url, options) do
- with executable when is_binary(executable) <- System.find_executable("convert"),
- {:ok, args} <- prepare_image_resize_args(options),
- {:ok, env} <- HTTP.get(url, [], pool: :media),
- {:ok, fifo_path} <- mkfifo() do
- args = List.flatten([fifo_path, args])
- run_fifo(fifo_path, env, executable, args)
- else
- nil -> {:error, {:convert, :command_not_found}}
- {:error, _} = error -> error
- end
- end
-
- defp prepare_image_resize_args(
- %{max_width: max_width, max_height: max_height, format: "png"} = options
- ) do
- quality = options[:quality] || 85
- resize = Enum.join([max_width, "x", max_height, ">"])
-
- args = [
- "-resize",
- resize,
- "-quality",
- to_string(quality),
- "png:-"
- ]
-
- {:ok, args}
- end
-
- defp prepare_image_resize_args(%{max_width: max_width, max_height: max_height} = options) do
- quality = options[:quality] || 85
- resize = Enum.join([max_width, "x", max_height, ">"])
-
- args = [
- "-interlace",
- "Plane",
- "-resize",
- resize,
- "-quality",
- to_string(quality),
- "jpg:-"
- ]
-
- {:ok, args}
- end
-
- defp prepare_image_resize_args(_), do: {:error, :missing_options}
-
- # Note: video thumbnail is intentionally not resized (always has original dimensions)
- def video_framegrab(url) do
- with executable when is_binary(executable) <- System.find_executable("ffmpeg"),
- {:ok, env} <- HTTP.get(url, [], pool: :media),
- {:ok, fifo_path} <- mkfifo(),
- args = [
- "-y",
- "-i",
- fifo_path,
- "-vframes",
- "1",
- "-f",
- "mjpeg",
- "-loglevel",
- "error",
- "-"
- ] do
- run_fifo(fifo_path, env, executable, args)
- else
- nil -> {:error, {:ffmpeg, :command_not_found}}
- {:error, _} = error -> error
- end
- end
-
- defp run_fifo(fifo_path, env, executable, args) do
- pid =
- Port.open({:spawn_executable, executable}, [
- :use_stdio,
- :stream,
- :exit_status,
- :binary,
- args: args
- ])
-
- fifo = Port.open(to_charlist(fifo_path), [:eof, :binary, :stream, :out])
- fix = Pleroma.Helpers.QtFastStart.fix(env.body)
- true = Port.command(fifo, fix)
- :erlang.port_close(fifo)
- loop_recv(pid)
- after
- File.rm(fifo_path)
- end
-
- defp mkfifo do
- path = Path.join(System.tmp_dir!(), "pleroma-media-preview-pipe-#{Ecto.UUID.generate()}")
-
- case System.cmd("mkfifo", [path]) do
- {_, 0} ->
- spawn(fifo_guard(path))
- {:ok, path}
-
- {_, err} ->
- {:error, {:fifo_failed, err}}
- end
- end
-
- defp fifo_guard(path) do
- pid = self()
-
- fn ->
- ref = Process.monitor(pid)
-
- receive do
- {:DOWN, ^ref, :process, ^pid, _} ->
- File.rm(path)
- end
- end
- end
-
- defp loop_recv(pid) do
- loop_recv(pid, <<>>)
- end
-
- defp loop_recv(pid, acc) do
- receive do
- {^pid, {:data, data}} ->
- loop_recv(pid, acc <> data)
-
- {^pid, {:exit_status, 0}} ->
- {:ok, acc}
-
- {^pid, {:exit_status, status}} ->
- {:error, status}
- after
- 5000 ->
- :erlang.port_close(pid)
- {:error, :timeout}
- end
- end
- end
|