From b1d72f768402bc1ea79903fcadbed22fb6263152 Mon Sep 17 00:00:00 2001
From: Mikael Finstad <finstaden@gmail.com>
Date: Sat, 29 Aug 2020 19:35:21 +0200
Subject: [PATCH] only add avoid_negative_ts when cutting start

---
 src/ffmpeg.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/ffmpeg.js b/src/ffmpeg.js
index 545e4fb2..69054ee6 100644
--- a/src/ffmpeg.js
+++ b/src/ffmpeg.js
@@ -223,12 +223,15 @@ async function cut({
 
   const copyFileStreamsFiltered = copyFileStreams.filter(({ streamIds }) => streamIds.length > 0);
 
+  // remove -avoid_negative_ts make_zero when not cutting start (no -ss), or else some videos get blank first frame in QuickLook
+  const avoidNegativeTsArgs = cuttingStart ? ['-avoid_negative_ts', 'make_zero'] : [];
+
   const inputArgs = flatMap(copyFileStreamsFiltered, ({ path }) => ['-i', path]);
   const inputCutArgs = ssBeforeInput ? [
     ...cutFromArgs,
     ...inputArgs,
     ...cutToArgs,
-    '-avoid_negative_ts', 'make_zero',
+    ...avoidNegativeTsArgs,
   ] : [
     ...inputArgs,
     ...cutFromArgs,