git.squeep.com Git - akkoma/blob - lib/pleroma/helpers/media_helper.ex

   1 # Pleroma: A lightweight social networking server
   2 # Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
   3 # SPDX-License-Identifier: AGPL-3.0-only
   4
   5 defmodule Pleroma.Helpers.MediaHelper do
   6   @moduledoc """
   7   Handles common media-related operations.
   8   """
   9
  10   def ffmpeg_resize(uri_or_path, %{max_width: max_width, max_height: max_height} = options) do
  11     quality = options[:quality] || 1
  12
  13     cmd = ~s"""
  14     ffmpeg -i #{uri_or_path} -f lavfi -i color=c=white \
  15       -filter_complex "[0:v] scale='min(#{max_width},iw)':'min(#{max_height},ih)': \
  16         force_original_aspect_ratio=decrease [scaled]; \
  17         [1][scaled] scale2ref [bg][img]; [bg] setsar=1 [bg]; [bg][img] overlay=shortest=1" \
  18       -loglevel quiet -f image2 -vcodec mjpeg -frames:v 1 -q:v #{quality} pipe:1
  19     """
  20
  21     pid = Port.open({:spawn, cmd}, [:use_stdio, :in, :stream, :exit_status, :binary])
  22     loop_recv(pid)
  23   end
  24
  25   defp loop_recv(pid) do
  26     loop_recv(pid, <<>>)
  27   end
  28
  29   defp loop_recv(pid, acc) do
  30     receive do
  31       {^pid, {:data, data}} ->
  32         loop_recv(pid, acc <> data)
  33
  34       {^pid, {:exit_status, 0}} ->
  35         {:ok, acc}
  36
  37       {^pid, {:exit_status, status}} ->
  38         {:error, status}
  39     end
  40   end
  41 end