pdfpc fails to play video

[veprbl]

Describe the bug
pdfpc can't play example video, it freezes instead.

To Reproduce

wget https://github.com/pdfpc/pdfpc/releases/download/v4.3.0/pdfpc-video-example.zip
nix run nixpkgs.unzip -c unzip pdfpc-video-example.zip
cd pdfpc-video-example
nix-shell -p pdfpc -p gst_all_1.gst-plugins-base -p 'gst_all_1.gst-plugins-good.override {gtkSupport=true;}' -p gst_all_1.gst-plugins-bad -p gst_all_1.gst-plugins-ugly -I nixpkgs=channel:nixpkgs-unstable --run "pdfpc -wS video-example.pdf"

2. Go to slide 5
3. Click on the video

Expected behavior
A clear and concise description of what you expected to happen.

Additional context
I'm able to play the video using the gstreamer:

nix-shell -p pdfpc -p gst_all_1.gst-plugins-base -p 'gst_all_1.gst-plugins-good.override {gtkSupport=true;}' -p gst_all_1.gst-plugins-bad -p gst_all_1.gst-plugins-ugly -I nixpkgs=channel:nixpkgs-unstable --run "gst-launch-1.0 filesrc location=apollo17.avi ! decodebin ! videoconvert ! gtksink"

Metadata

• system: "x86_64-linux"
• host os: Linux 4.14.90, NixOS, 18.09.1810.c840631fe20 (Jellyfish)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.1.3
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos

Maintainer information:

# a list of nixpkgs attributes affected by the problem
attribute:
 - pdfpc
# a list of nixos modules affected by the problem
module:

Possibly related to #43551
cc @pSub

[KnairdA]

I just encountered the same problem. I was able to fix it locally by changing the build inputs of the derivation to:

  buildInputs = with pkgs; [
    gtk3 libgee poppler librsvg pcre
  ] ++ (with pkgs.gst_all_1; [
    gstreamer
    gst-plugins-base
    (gst-plugins-good.override { gtkSupport = true; }) 
    gst-libav
  ]);

Just enabling the GTK support was not sufficient, I also had to add the gst-libav package.

[veprbl]

@KnairdA This is great! Would you mind submitting a PR?

[KnairdA]

Sure!