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  1. Hi! I've recorded a bunch of channels with my DVB-T box and it exports in .MTS.

    The editing goes very well in Avidemux but when I export it, in the very beggining of the video, it leaves a 0.5 second non-recorded. The original recording is perfect.
    Is this a problem with Avidemux? Or with the recording?

    Here's an example: Notice that at 00:00 it contains audio before the cut.
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  2. There doesn't seem to be anything particularly odd about your sample to me. I tried a few different players (MPC-HC, VLC, Potplayer) and there was no noticeable delay for video or audio.

    Best as I could tell looking at the MP4, because I know very little about MP4, there's an 80ms video delay. When I remuxed the MP4 as an MKV with MKVToolNix and checked it, and the MKV had the same 80ms delay for the video, but at 25fps, 80ms is only the duration of two frames, so it shouldn't be a problem.

    ffdshow's on screen display agrees (see attached image). For a constant frame rate the first frame is frame zero, and frames are effectively counted even if they don't exist, which is why the first frame I see appears as frame number two beginning at 80ms.

    You could try setting an 80ms delay for the audio. Then the video and audio delays should cancel each other out, but it might mess with the audio sync. I've no idea why Avidemux is setting an 80ms video delay. I don't use it. Maybe your source file has the same video delay and Avidemux isn't changing it, even when you edit.

    As you can see from my screenshot below, MPC-HC isn't displaying your sample with the correct aspect ratio. Neither did MPC-BE. VLC and SMPlayer did. I suspect Avidemux is only writing the aspect ratio to the video stream and MPC-HC seems to look for the container aspect ratio (MP4, or MKV aspect ratio etc). That's probably a MPC-HC issue if anything, but I'd try opening your output file with MyMP4Box (or MKVToolNix) and setting the correct 16:9 display aspect ratio so the video stream and container aspect ratios are the same.
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  3. There are 2 streams. hello_hello is probably listening to English. OP is probably not. The Portugese stream has a delay offset and has a "blip" from the previous scene. You can solo each track and listen to the separately

    Did you cut on keyframes in avidemux ?

    I suspect they were already offset like that to begin with. You can try "fixing" it with an audio shift of the Portugese track, assuming the English track is the one in sync
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  4. Member netmask56's Avatar
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    Sep 2005
    Sydney, Australia
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    Download the trial version of TSDoctor and let it process and demux it for you. Then remux together with the audio of your choice.
    SONY 75" Full array 200Hz LED TV, Yamaha A1070 amp, Zidoo UHD3000, BeyonWiz PVR V2 (Enigma2 clone), Chromecast, Windows 7 Ultimate, QNAP NAS TS851
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