[#2497] Image preview proxy: image resize & background color fix with ffmpeg -filter_complex.

This commit is contained in:
Ivan Tashkinov 2020-05-21 17:35:42 +03:00
parent 6fd4f58ead
commit 610343edb3
2 changed files with 9 additions and 45 deletions

View file

@ -9,12 +9,14 @@ defmodule Pleroma.Helpers.MediaHelper do
@ffmpeg_opts [{:sync, true}, {:stdout, true}]
def ffmpeg_resize_remote(uri, max_width, max_height) do
def ffmpeg_resize_remote(uri, %{max_width: max_width, max_height: max_height}) do
cmd = ~s"""
curl -L "#{uri}" |
ffmpeg -i pipe:0 -vf \
"scale='min(#{max_width},iw)':min'(#{max_height},ih)':force_original_aspect_ratio=decrease" \
-f image2 pipe:1 | \
ffmpeg -i pipe:0 -f lavfi -i color=c=white \
-filter_complex "[0:v] scale='min(#{max_width},iw)':'min(#{max_height},ih)': \
force_original_aspect_ratio=decrease [scaled]; \
[1][scaled] scale2ref [bg][img]; [bg] setsar=1 [bg]; [bg][img] overlay=shortest=1" \
-f image2 -vcodec mjpeg -frames:v 1 pipe:1 | \
cat
"""
@ -22,41 +24,4 @@ def ffmpeg_resize_remote(uri, max_width, max_height) do
{:ok, Enum.join(stdout_list)}
end
end
@doc "Returns a temporary path for an URI"
def temporary_path_for(uri) do
name = Path.basename(uri)
random = rand_uniform(999_999)
Path.join(System.tmp_dir(), "#{random}-#{name}")
end
@doc "Stores binary content fetched from specified URL as a temporary file."
@spec store_as_temporary_file(String.t(), binary()) :: {:ok, String.t()} | {:error, atom()}
def store_as_temporary_file(url, body) do
path = temporary_path_for(url)
with :ok <- File.write(path, body), do: {:ok, path}
end
@doc "Modifies image file at specified path by resizing to specified limit dimensions."
@spec mogrify_resize_to_limit(String.t(), String.t()) :: :ok | any()
def mogrify_resize_to_limit(path, resize_dimensions) do
with %Mogrify.Image{} <-
path
|> Mogrify.open()
|> Mogrify.resize_to_limit(resize_dimensions)
|> Mogrify.save(in_place: true) do
:ok
end
end
defp rand_uniform(high) do
Code.ensure_loaded(:rand)
if function_exported?(:rand, :uniform, 1) do
:rand.uniform(high)
else
# Erlang/OTP < 19
apply(:crypto, :rand_uniform, [1, high])
end
end
end

View file

@ -82,17 +82,16 @@ defp thumbnail_max_dimensions(params) do
{thumbnail_max_width, thumbnail_max_height}
end
defp handle_preview("image/" <> _ = content_type, %{params: params} = conn, url) do
defp handle_preview("image/" <> _ = _content_type, %{params: params} = conn, url) do
with {thumbnail_max_width, thumbnail_max_height} <- thumbnail_max_dimensions(params),
media_proxy_url <- MediaProxy.url(url),
{:ok, thumbnail_binary} <-
MediaHelper.ffmpeg_resize_remote(
media_proxy_url,
thumbnail_max_width,
thumbnail_max_height
%{max_width: thumbnail_max_width, max_height: thumbnail_max_height}
) do
conn
|> put_resp_header("content-type", content_type)
|> put_resp_header("content-type", "image/jpeg")
|> send_resp(200, thumbnail_binary)
else
_ ->