Audio sync is not applied to exported video

Bug
1

What is your operating system?
Windows 10

What is your Shotcut version (see Help > About Shotcut)?
23.07.29

Can you repeat the problem? If so, what are the steps?
(Please be specific and use the names as seen in Shotcut, preferably English. Include a screenshot or screen recording if you can. Also, you can attach logs from either View > Application Log or right-click a job and choose View Log.)

Open any video; Append to track; Goto Properties/Audio; Change Sync; Export video

Audio sync is not applied to exported video. (But it works in the player/preview)

The sync value is saved in the mlt file - e.g.

<property name="video_delay">-0.1</property>

(-100ms delay)

This feature worked in older versions. (Unfortunately I don’t know when it stopped working.)

Best regards
Thomas

2

It is working for me. Here is my test procedure:

  1. Open Shotcut
  2. Set the video mode to HD 1080p 30 fps
  3. Choose Open->Other->Blip Flash
  4. In the source player, trim the blip flash clip to 30 seconds
  5. Export the blip flash clip using default export settings. Use the name “blipflash.mp4”
  6. Close the project
  7. Open blipflash.mp4
  8. Open the properties panel, click the audio tab, set the “Sync” parameter to “-100ms”
  9. Export the delayed blip flash clip using default export settings. Use the name “blipflash-100.mp4”
  10. Open a command prompt and run the following command:

path-to-shotcut/melt.exe -silent path-to-export/blipflash.mp4 -consumer blipflash

Note, use the appropriate paths for your own system/installation. “melt.exe” is provided with the Shotcut package and is in the same directory as “shotcut.exe”.

  1. Notice that the printed status shows 0ms delay for the original blipflash clip
frame sync
0 0.00
30 0.00
60 0.00
90 0.00
120 0.00
150 0.00
180 0.00
210 0.00
240 0.00
270 0.00
300 0.00
330 0.00
360 0.00
390 0.00
  1. Run the same melt command for the delayed clip:

path-to-shotcut/melt.exe -silent path-to-export/blipflash-100.mp4 -consumer blipflash

  1. Notice that the printed status shows -100ms delay for the delayed blipflash clip
frame sync
0 ??
30 -100.00
60 -100.00
90 -100.00
120 -100.00
150 -100.00
180 -100.00
210 -100.00
240 -100.00
270 -100.00
300 -100.00
330 -100.00
360 -100.00

Can you provide more information about how you measure the delay in your exported file?