From 4ef10b082b6b01c40b2ab5d41d88b3a4b90aaa52 Mon Sep 17 00:00:00 2001
From: valadaptive <valadaptive@protonmail.com>
Date: Sun, 20 Oct 2024 21:50:46 -0400
Subject: [PATCH] Fix variable-framerate videos in standalone app

---
 crates/gui/src/app/main.rs                 |  4 +++-
 crates/gui/src/gst_utils/pipeline_utils.rs | 15 +++++++++++++--
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/crates/gui/src/app/main.rs b/crates/gui/src/app/main.rs
index 9331c7d..487a931 100644
--- a/crates/gui/src/app/main.rs
+++ b/crates/gui/src/app/main.rs
@@ -1381,7 +1381,9 @@ impl NtscApp {
                 .structure(0)?
                 .get::<gstreamer::Fraction>("framerate")
                 .ok()?;
-            Some(framerate)
+
+            // If the framerate is 0, treat it like it's absent
+            (framerate.numer() != 0).then_some(framerate)
         })();
 
         egui::TopBottomPanel::top("video_info")
diff --git a/crates/gui/src/gst_utils/pipeline_utils.rs b/crates/gui/src/gst_utils/pipeline_utils.rs
index 101050c..de37c8a 100644
--- a/crates/gui/src/gst_utils/pipeline_utils.rs
+++ b/crates/gui/src/gst_utils/pipeline_utils.rs
@@ -1,5 +1,5 @@
 use super::{gstreamer_error::GstreamerError, scale_from_caps};
-use gstreamer::{element_error, element_warning, glib, prelude::*};
+use gstreamer::{element_error, element_warning, glib, prelude::*, query::Duration};
 use gstreamer_video::VideoInterlaceMode;
 use log::debug;
 use std::{
@@ -220,11 +220,22 @@ pub fn create_pipeline<
                             ))
                         });
 
-                        let is_still_image = match framerate {
+                        let mut q = Duration::new(gstreamer::Format::Time);
+                        let _ = src_pad.query(q.query_mut());
+                        let src_duration = q.result();
+                        let has_duration = src_duration.is_some();
+
+                        let has_zero_framerate = match framerate {
                             Some(framerate) => framerate.numer() == 0,
                             None => false,
                         };
 
+                        // TODO: Videos with a variable framerate have a framerate of 0, so we also check if the input
+                        // has a defined duration (see https://github.com/valadaptive/ntsc-rs/issues/8). Since we do so,
+                        // is it still necessary to have *both* checks? Are there some videos that are not still images
+                        // but still have no duration?
+                        let is_still_image = has_zero_framerate && !has_duration;
+
                         let video_sink = video_sink(
                             &pipeline,
                             VideoElemMetadata {