1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
|
# Pleroma: A lightweight social networking server
# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Upload.Filter.AnalyzeMetadata do
@moduledoc """
Extracts metadata about the upload, such as width/height
"""
require Logger
alias Vix.Vips.Image
alias Vix.Vips.Operation
@behaviour Pleroma.Upload.Filter
@spec filter(Pleroma.Upload.t()) ::
{:ok, :filtered, Pleroma.Upload.t()} | {:ok, :noop} | {:error, String.t()}
def filter(%Pleroma.Upload{tempfile: file, content_type: "image" <> _} = upload) do
try do
{:ok, image} = Image.new_from_file(file)
{width, height} = {Image.width(image), Image.height(image)}
upload =
upload
|> Map.put(:width, width)
|> Map.put(:height, height)
|> Map.put(:blurhash, get_blurhash(image))
{:ok, :filtered, upload}
rescue
e in ErlangError ->
Logger.warning("#{__MODULE__}: #{inspect(e)}")
{:ok, :noop}
end
end
def filter(%Pleroma.Upload{tempfile: file, content_type: "video" <> _} = upload) do
try do
result = media_dimensions(file)
upload =
upload
|> Map.put(:width, result.width)
|> Map.put(:height, result.height)
{:ok, :filtered, upload}
rescue
e in ErlangError ->
Logger.warning("#{__MODULE__}: #{inspect(e)}")
{:ok, :noop}
end
end
def filter(_), do: {:ok, :noop}
defp get_blurhash(file) do
with {:ok, blurhash} <- vips_blurhash(file) do
blurhash
else
_ -> nil
end
end
defp media_dimensions(file) do
with executable when is_binary(executable) <- System.find_executable("ffprobe"),
args = [
"-v",
"error",
"-show_entries",
"stream=width,height",
"-of",
"csv=p=0:s=x",
file
],
{result, 0} <- System.cmd(executable, args),
[width, height] <-
String.split(String.trim(result), "x") |> Enum.map(&String.to_integer(&1)) do
%{width: width, height: height}
else
nil -> {:error, {:ffprobe, :command_not_found}}
error -> {:error, error}
end
end
defp vips_blurhash(%Vix.Vips.Image{} = image) do
with {:ok, resized_image} <- Operation.thumbnail_image(image, 100),
{height, width} <- {Image.height(resized_image), Image.width(resized_image)},
max <- max(height, width),
{x, y} <- {max(round(width * 5 / max), 1), max(round(height * 5 / max), 1)} do
{:ok, rgb} =
if Image.has_alpha?(resized_image) do
# remove alpha channel
resized_image
|> Operation.extract_band!(0, n: 3)
|> Image.write_to_binary()
else
Image.write_to_binary(resized_image)
end
Blurhash.encode(rgb, width, height, x, y)
else
_ -> nil
end
end
end
|
