New AAC encoder and video speed set by frame rate

The AAC encoder in Shotcut seems to be very inefficient and sounds really bad at bitrates like 192kbit/s which is no issue for the Vegas AAC codec. Open Source encoders like NeroAAC are probably a good choice. And since I am muxing 23,976fps videos with PAL from a 25fps source, it would be very nice to have a option to change the FPS of a video which then affects the speed of the playback. I know this can take some time, but these are features I love in Vegas which I would love to see in Shotcut since Vegas has color problems which limit my workflow there (colors are just wrong no matter what I do) :woozy_face:

We use the AAC encoder built into FFmpeg and will not be integrating anything else unless FFmpeg does. The FDK implementation is not acceptable due to licensing restrictions.

Aw :confused:
And what about the speed changing using framerates?

That is very esoteric, and I am not going to work on it before the long list of more basic and important things. Maybe someone else will.

This is a late reply and question but is it possible to use the FDK AAC codec? I guess it is included in the Ffmpeg library already. https://trac.ffmpeg.org/wiki/Encode/AAC#fdk_aac
It can be built in to ffmpeg manually as far as I know, would it be likely to see a high quality option in the future?

According to that ffmpeg webpage:

The license of libfdk_aac is not compatible with GPL, so the GPL does not permit distribution of binaries containing incompatible code when GPL-licensed code is also included. Therefore this encoder have been designated as “non-free”, and you cannot download a pre-built ffmpeg that supports it. This can be resolved by compiling ffmpeg yourself.

Hence I believe that Shotcut (also licencsed under GPL) is not allowed to be distributed with this.

Also, the ffmpeg website states:

As of 2017 libfdk_aac may not always be better than aac for AAC-LC. The built in aac encoder is quite good.

I’m not sure if there is a regression in FFmpeg or not, but I and a few others here have noticed the built-in AAC encoder not being all we hoped for anymore as well. Although I haven’t had any serious problems at 192 and above, I have noticed it not keeping par with other encoders at lower bitrates. So for those purposes, I’ve switched to AC-3 and had excellent results. Might work for you too.

Just to clarify… are you encoding 192 stereo or surround sound? With FFmpeg, the bitrate represents the total stream, so 192kbps / 5.1surround = 32kbps per channel, which would indeed sound very bad.