editing out ads but AR changed

[VanZan]

I have a Rpi with TVHeadend making DVB-T recordings. My laptop runs Manjaro Linux. I want to edit out the ads from my mkv recordings. Avidemux seems to be the best video editor for Linux that doesn't require the file to be re-encoded after editing.

I use AviDemux and everything seemingly goes fine. However when I play the edited file the AR is different with the video squeezed more into the middle.

I tried Avidemux under Windows as well and the same thing happens. Is there any solution to this please? At the moment I have to reboot into Windows and use VideoRedo and then reboot to Manjaro which is a pain.

I tried the MKV muxer options of Force Display Width or Force Aspect Ratio (DAR) and couldn't solve the problem.

Thanks for any help!

[butterw]

- What is the source resolution and DAR ? You have to re-apply the same DAR when you save.

- Also, not all players support mkv container DAR, what are you playing the file with ?

[VanZan]

Hi thanks for the reply. Suprisingly I think I solved it. The source file was reporting itself to be 1440x1080. By setting "Force Display Width" to 1920 it looks right now.

I say "suprisingly" because I would have thought I would have tried that before. Bit embarrassing.

Also I'm now getting the warning regarding non-IDR. So I got to figure out if there is a TVHeadend option to solve that now.

[eumagga0x2a]

Also I'm now getting the warning regarding non-IDR. So I got to figure out if there is a TVHeadend option to solve that now.

This is the property of the H.264 or HEVC stream as created by broadcaster or the cable company. There are almost no IDR frames in digital TV broadcasts. This is beneficial for quality but detrimental to editability.

Strictly speaking, open-GOP type of H.264 or HEVC streams cannot be edited by cutting away an inner portion of the stream without making the structure of the stream invalid. However, all popular decoders can cope with such cuts as long as the internal counter which determines the display order of pictures (POC) increases across a cut.

Many decoders handle also abruptly diminishing POC well (they reset the internal counter and live on). Unfortunately, the super-popular libavcodec at heart of VLC, mpv and a lot of other applications including Avidemux doesn't belong to those decoders. This is the reason this warning was implemented in Avidemux. If you are sure that the result doesn't need to be playable in VLC & Co., you can ignore it. Most smartphones as well the default video player app on Windows 10 will play it just fine.