Avidemux Forum

Quote from: eumagga0x2a on October 29, 2024, 11:03:55 AMThank you, might be fixed now, but can't tell for sure without a sample. Please try a future nightly build.

I tried to post the video Mega link, but I got: CleanTalk: *** Forbidden. HTTP links blacklisted. Please enable JavaScript. Anti-Spam by CleanTalk. ***

Thank you, might be fixed now, but can't tell for sure without a sample. Please try a future nightly build.

Quote from: eumagga0x2a on October 26, 2024, 05:20:57 AMDoes this happen with the latest available 2.8.2 nightly build?

If it does, please provide a sample.

If the file size is too large for the file to be provided as a sample by the usual tools as WeTransfer, Mega, Dropbox or Google Drive, please at least attach MediaInfo textual analysis for the file in question to your reply (don't try to paste it into the body of the post, CleanTalk is allergic against MediaInfo for whatever reason).

Quote from: johnr283 on October 24, 2024, 01:21:48 AMIf I change the output to AAC, the video won't play correctly.

But it will if you disable the DTS audio track, right?

It still happens with the latest nightly build.

Here is the MediaInfo: https://mega.nz/file/o54kwbhI#YNVIr_hwXofhae2sDVQCcJ6Fnu_sZ93SkgAIDyeMQQU

I confirm the version "2.8.2 / 240906" fixes the problem.
Thank you, I was reluctant to use a beta version, that's why I was using 2.8.1.
Regards,

Quote from: coré on October 26, 2024, 07:04:47 PMI want to convert a 29.970 interlaced video to 23.976 fps (which will therefore be deinterlaced) but when I try to modify the framerate in Avidemux, it also modifies the duration of the video.

The video filter performing this operation without modifying duration is called "Resample".

Quote from: coré on October 26, 2024, 07:04:47 PMin Avisynth, for the videos I want to process, I apply: tdeint mode 2 but this does not seem to exist in Avidemux.

What would be closest to it?

I cannot tell how close the results are to TDeint, but the best cross-platform deinterlacer in Avidemux is Yadif in picture-per-field mode. On Linux, hardware accelerated deinterlacers (VDPAU and VA-API) work pretty great on hardware with necessary capabilities IMHO.

Quote from: question on October 26, 2024, 05:48:52 PMWhy does Avidemux say the optimal is two pass average + target bitrate of 0 then?

Honestly, I am not sure that this configuration works as intended. The idea was to benefit from reasonably chosen keyframes, which requires 2-pass mode, but at the same time to ask the libvpx library to do constant quality encoding. However, rc_max_quantizer (libvpx parameter describing the worst permitted quality) is set to the maximum allowed value rather than to rc_min_quantizer (libvpx parameter describing the best permitted quality) which Avidemux sets to 20. The output has a very high visual quality, else I would have written "best compression" ;-)

Quote from: question on October 26, 2024, 05:48:52 PMI dont understand why converting mp4 to webm results in an increased file size...

Every generation of lossy encoding worsens the quality and/or inflates the size of stream. This is a general rule. If the original stream was encoded using a very efficient codec like HEVC, re-encoding to VP9 will hardly allow to keep the same stream size without a substantial quality loss. If you really need to keep file size same or smaller, write down the average bitrate Avidemux displays in the video properties dialog for the original video and configure the VP9 encoder to use 2-pass mode with a bitrate slightly below (and also lower the value for "Speed").

Hello,

Here, I want to convert a 29.970 interlaced video to 23.976 fps (which will therefore be deinterlaced) but when I try to modify the framerate in Avidemux, it also modifies the duration of the video.

Usually, I go through Avisynth for this kind of manipulation and by doing a Decimate, I can do this without modifying the video timer.

Is such a thing possible in Avidemux and if so, how?

I take this opportunity to ask you another question about deinterlacing: in Avisynth, for the videos I want to process, I apply: tdeint mode 2 but this does not seem to exist in Avidemux.

What would be closest to it? Better yet, is it possible to make Tdeint work in Avidemux and if so, how?

Thanks.

Quote from: eumagga0x2a on October 26, 2024, 02:21:52 PM

Quote from: sark on October 26, 2024, 01:32:49 PMChanging to Constant Bitrate should reduce output size (significantly in some cases).

Please don't, constant bitrate is almost always a poor choice – just the default configuration of the libvpx VP9 encoder plugin is even worse.

Please use the 2-pass average bitrate option with an actually reasonable, non-zero bitrate. If I am not mistaken, two-pass is unfortunately the only way to make libvpx insert keyframes at scene changes rather than stupidly following the specified GOP length.

If keyframes placing is not important for you, use constant quantizer mode. Increasing "Speed" beyond "4" allows for much faster operation at the cost of massively worse compression.

Why does Avidemux say the optimal is two pass average + target bitrate of 0 then? Thats also the default setting. What should i use to keep reasonable quality but have the same or lower file size? I dont understand why converting mp4 to webm results in an increased file size...

Quote from: sark on October 26, 2024, 01:32:49 PMChanging to Constant Bitrate should reduce output size (significantly in some cases).

Please don't, constant bitrate is almost always a poor choice – just the default configuration of the libvpx VP9 encoder plugin is even worse.

Please use the 2-pass average bitrate option with an actually reasonable, non-zero bitrate. If I am not mistaken, two-pass is unfortunately the only way to make libvpx insert keyframes at scene changes rather than stupidly following the specified GOP length.

If keyframes placing is not important for you, use constant quantizer mode. Increasing "Speed" beyond "4" allows for much faster operation at the cost of massively worse compression.

Quote from: question on October 26, 2024, 11:59:52 AMNow my problem is that when i convert a mp4 file to webm using avidemux, for some reason the file size is actually larger?

Many factors determine output size. By default I believe Avidemux uses 2 pass encoding for VP9. Changing to Constant Bitrate should reduce output size (significantly in some cases).