fixed frame timing from debug info

2 files changed, 5 insertions, 3 deletions

diff --git a/README.md b/README.md
index 9089135..957cf5d 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,2 @@
 # yt-frame-timer
-A JavaScript-based program to determine the time between start and end points of a YouTube video down to the frame. Based on [https://docs.google.com/spreadsheets/d/1c3eiw1_00Tx1snAdU_kvncuA8C8xu5-q3tSOPRuqhzI/](https://docs.google.com/spreadsheets/d/1c3eiw1_00Tx1snAdU_kvncuA8C8xu5-q3tSOPRuqhzI/).
\ No newline at end of file
+A JavaScript-based program to determine the time between start and end points of a YouTube video down to the frame. Based on [https://docs.google.com/spreadsheets/d/1c3eiw1_00Tx1snAdU_kvncuA8C8xu5-q3tSOPRuqhzI/](https://docs.google.com/spreadsheets/d/1c3eiw1_00Tx1snAdU_kvncuA8C8xu5-q3tSOPRuqhzI/) by Slush Puppy (big thanks to them for their work).
\ No newline at end of file
diff --git a/main.js b/main.js
index 66e1e10..1deac10 100644
--- a/main.js
+++ b/main.js
@@ -8,8 +8,10 @@ function compute() {
     let seconds = 0;
     let milliseconds = 0;
     let frameRate = parseInt(framerate);
-    let diff = (endObj.lct - startObj.lct) * frameRate;
-    let frames = diff;
+    let frameFromObj = (time, fps) => Math.floor(time * fps) / fps; //round to the nearest frame
+    let startFrame = frameFromObj(startObj.lct, frameRate);
+    let endFrame = frameFromObj(endObj.lct, frameRate);
+    let frames = (endFrame - startFrame) * frameRate;
     if (frames >= frameRate) {
         seconds = Math.floor(frames / frameRate);
         frames = frames % frameRate;