The VideoLAN Forums

hi,

I am trying to use VLC to convert wmv to mp4. My wmv file was created from MS Powerpoint - I exported some powerpoint slides to wmv, together with embedded audio files, which are in wav format.

I did the conversion with the following settings:

Profile: Video for MPEG4 720p TV/device
Encapsulation: MP4/MOV
Video: codec is H-264; bitrate is 1024 kb/s
Audio: codec is MPEG4 Audio (AAC); bitrate is 192 kb/s

When I ran that, I got an error "VLC could not open the mp4a audio encoder." So, after the mp4 file was created, there was no audio, although the video was fine.

I also tried to play around with other audio codecs - although other options did not give me an error message, there was still no audio in the mp4.

Could someone pls help?

Thanks.

Just to add: I need the final mp4 to be 720p, which is why I am using that profile.

I had the same issue: no audio converting to a .mp4 file and getting the same error about the mp4a encoder. I found the "answer" buried in another posting here:

https://forum.videolan.org/viewtopic.ph ... er#p413027

I set the ffmpeg option: "Strict standard compliance to -2 " and then it converted correctly. The 2013 june 25th post by Mahal explains how to set this.
Good luck

hi there, thanks a bunch. i will give it a try!

Hello! So I am running into the same situation as mahal did in his original post but now that it is September of 2016, his solution no longer works. I am using VLC 2.2.4 Weathermax 32-bit. and whatever option/settings layout you all had in 2.1.4 is not the same as it is now. As a result, I cannot find anything to do with ffmpeg in the settings. Either under 'Audio' or 'Input/Codec' settings. If someone knows where these settings could be found I would greatly appreciate you pointing me in the right direction. Please help.

THE FIX: This is a common problem that can be solved by ensuring that the conversion audio bitrates matches.

Open file you wish to convert. While file is playing, under Tools, select Codec information. For notice the audio bit rate.

When you make the conversion, under settings, make sure the audio bit rate you're converting to matches.

For whatever reasons, VLC doesn't automatically downgrade audio bit rate. So if your original audio bit rate is 48000 and your audio setting is set at 44100, VLC would generate a converted file without audio!

Good luck!

For whatever reasons, VLC doesn't automatically downgrade audio bit rate. So if your original audio bit rate is 48000 and your audio setting is set at 44100, VLC would generate a converted file without audio!

Good luck!

I don't see such issue in 3.0.
I've just converted flac 44100 to AAC 48000 in mp4 without problem