How to extract audio from long movies

[jparnold]

I have an MP4 movie which is quite long and I would like to extract the audio to a file.
I have loaded the movie into the timeline but when I extract the audio (CREATE SOUND FILE) it only extracts the first 18 minutes 20 seconds. I have tried using VS6 and VS10 with the samje result.
Is there a setting which is limiting the length of the output? If not can anyone suggest a freeware audio extractor?

Thanks

[remmyhi]

You can extract the audio from the video, remove the video track and share the project as audio only.

[jparnold]

Thanks
I am assuming that you mean that I should drag the video clip onto the audio track?

[remmyhi]

No, drag it on Video track, then right click on it --> Audio --> Split Audio, then remove the video track. Just let audio stay. Then go to share and share with Audio only.

[jparnold]

Thanks
It's been a while since I last edited movies and have in the past often split the audio from a video clip so that I could replace it with something else.

HOWEVER I ended up with the same problem BUT then noticed that the output WAV file was 4.18GB in length and although I have a 64bit system I remembered that was a filesize limit so will have to 'extract' to a different format. Problem is though that Audacity won't accept WMA or M4A (audio) files due to patent restrictions (to convert to MP3). Any ideas?

[canuck]

How long in time is your source file? There is no 4GB file size limit unless you are "rendering" to a non-NTSC( ie, FAT) device. I just extracted the audio from a over 2 hour movie the wav file that was generated is only 1.5GB in size.
Exactly what process/steps are you following? There is no need to first split the audio from the video as remmyhi suggested. You simply click Share and the click Audio and then select the output format to create the audio file.

[RobertOZ]

What canuck has suggested is by far the simplest way of achieving an audio only file

[jparnold]

Answers to questions -

I did originally not split the audio but simply placed the MP4 file onto a video track and then attempted to output to a sound file. I only split on recommendation from another (it made no difference).

Video file (MP4) is 752mb in size and is over 7 hours long (yes extremely long as it is a book being read with no moving video just an image of the book's cover which I wanted as an MP3 file which I could add to my mobile/cell phone to listen to at leisure).

My devices are all formatted to NTFS which I thought does not have a 4gb filesize limit - is this what VS is doing (limiting output files to 4gb)?

I have repeatedly done the same exercise (output to a WAV sound file with the same problem of just 18 minutes of sound being created because of filesize limit).

I have been successful outputting to a WMA sound file which is 62mb and just found that my mobile phone will play WMA sound files - I should have checked that first.

I would though be still interested in knowing why VS limits an output filesize to 4GB when the output device is NTFS. All my storage devices are NTFS. I find this interesting and disturbing.

[canuck]

I don't know where you are going wrong but I just created a 5.8GB wav file by extracting the audio from a over 9 hour video. (I added the same 2:22hour movie 4 times to the timeline). So it is not a VS 4GB limit.
I have to add that I am using VS2020 so perhaps something has changed over the versions

[asik1]

No need for VS , any converter will do so, like handbrake or XMediaRecode

[canuck]

No need for any 3rd part converters as VS does it just fine

[jparnold]

Thanks again for your interest and suggestions.
There is no need to take this further now that I have found that my mobile/cell phone can play WMA audio files. I thought that I needed MP3 and as VS can't do MP3 I decided on WAV and then convert that with Audacity.
I still have no idea why I was getting only 18 minutes of (WAV) audio audio file and all I could think of was that it had something to do with a filesize limit and I know that FAT32 has that filesize limit (4Gb) yet ALL of my devices (I have 2 HDD and 1 SDD drive) are formatted as NTFS. Could it be that VS6 and VS10 are 32 bit applications (not 64 bit) I wonder? I thought that VS10 was a 64bit application but in any case I cannot think that would have any effect.

Anyway outputting to a WMA file which it seems are smaller than an equivalent MP3 even though they are both 'lossy' and as it is only the (freq) range of a human voice it is good enough.

[Davidk]

X10 is a 64bit app. Whether you have it - can be checked. Help About will tell you.

As to phones playing wma vs mp3; my android 8 phone cannot play wma file because the phone OS won't display that filetype, even if (connected to a PC) the file is in the memory. It displays only mp3, and thus will only play that music filetype.

[jorgensen]

Taken from Wiki:
The WAV format is limited to files that are less than 4 GiB, because of its use of a 32-bit unsigned integer to record the file size header. Although this is equivalent to about 6.8 hours of CD-quality audio (44.1 kHz, 16-bit stereo), it is sometimes necessary to exceed this limit, especially when greater sampling rates, bit resolutions or channel count are required. The W64 format was therefore created for use in Sound Forge. Its 64-bit header allows for much longer recording times.

You could consider AAC which is more or less standard for today video editing as well as iPhone standard.

[jparnold]

Aha! I knew there must have been a reason (WAV files limited to 4Gb). I wonder though how canuk managed a 5.8Gb WAV file. Thanks heaps for that information.

I have now found on Wkipedia -

The WAV format is limited to files that are less than 4 GiB, because of its use of a 32-bit unsigned integer to record the file size header.

How did you manage a 5.8Gb WAv file, Canuk?


David I have a 3 year old Samsung J2 mobile phone which runs Android Nougat (version 7) and have no problems playing WMA sound files.

Unless my phone can't play WMA files AAC isn't an option as neither VS6 or VS10 can create them but thanks for the suggestion.