1 (edited by Tyr Antilles 2015-11-01 10:07:31)

Topic: Adjust Audio/Video desynchronization with Hybrid w direct stream copy

I have encountered several video files where on the output, audio stream is not synchronized with video stream (audio plays too early or audio plays too late). Assuming the delay is constant on the entire file, Hybrid offers the option to move the audio stream with a chosen amount of milliseconds, up or down on the timeline, very fast, without the need to reencode the entire file (direct stream copy for both, video and audio streams).

Step 1:  Determine how big the delay is. This is approximative. You need to watch the transcoded source file and estimate if audio plays too early or too late and by how much (1sec = 1000ms, 0.5sec = 500ms, etc.)

Step 2:  Open Hybrid and on Main set Video handling = passthrough and Audio handling = custom. Load the file you want to modify.

Step 3: Go to Audio tab and be sure "Reencode" is not checked, then set A/V delay (ms). Use positive value if audio plays too early and negative values if audio plays too late.
For example, if in your source file the audio stream plays about half a second too early, you need to set A/V delay a positive value of 500 ms.

Step 4: Add current audio stream on queue using + button

Step 5: Go to main, add the file on queue and start transcoding. It should just copy audio and video streams adjusting the delay, without reencoding anything.

Step 6: Examine the new resulting file to see if Audio/Video streams now match. If they don't, just repeat everything from Step 3, entering a different delay. I usually get it right in two - three tries.

I hope this helps. If someone find something wrong with what I said above, please correct me.