FFAStrans forum

I tested with several files...
Movies of about 100 minutes...
strarting from a quicktime, it give me back a WAV file with a right "weight" in terms of MB
but when i play o reimport it gives me back a 75 minuts file MAX!

what i am doing wrong?


L

Hello Backlight,

Ok, I will try tomorrow with a big file. I will give feedback. Your file was quicktime but which codec?
Are you on FFastrans 0.9.4.1 ?

Cheers.

Benjamin

hey, a normal riff wave is by default limited to 4gb afaik, depending in the bits, channels, samplerate, this limits the max duration. e.g. 16ch 48000hz, 16 bit would have a max of 10minutes. It is not the file size but the duration that underlies that limit.
Only the bwav extension solves this problem but i dont know if or how you can use it.. possibly it is ok for you to go with one wav per mono channel or use some other container than .wav. actually most containers would suffice and is able to carry PCM content only, e.g. mov, mp4, mpeg, avi etc...


see "limitations" here:
https://en.wikipedia.org/wiki/WAV

Yeha… i know it… but i hope in something in ffmpeg in order to write a BWAV file instead of the normal one!

Luiciano,

come on, searching for ffmpeg related stuff on google is really not hard. The wiki page i sent you specifies that the extension of interest is called "rf64". Using that and ffmpeg in google turns up to some promising solution, e.g. this creates a 4,3GB file that works:
This is just not the right place to ask ffmpeg related questions, it seems we really don't have experts for that here. A better place is the ffmpeg user mailing list or stackoverflow. Be aware that on stackoverflow, you need to specify "a proof of research", so you show people that you already researched the topic but you were not able to find an answer for it. That is a good style to ask questions in general.

Cheers,
emcodem

I'm sorry emcodem if I don't seems to be soooo expert on FFMPEG.
I tried to use the audio extraction node... if you read better I never asked for a custom ffmpeg code... but why is not possible to write bwav file using the ffastrans node.

This post is referred only to the audio extract node inside ffastrans.

The other "strange" things is that the resulting file has the right weight (in terms of Mb) but not the wright length.

Hey,
ok, it is new to me that you are referring to the audio extractor node. In this case your options are:
-) use another wrapper than wav, e.g. AIFF
-) extract each channel into mono wav (in case you dont need to support more than about 13 hours)
-) choose the PCM "wrapper" and use a custom ffmpeg node to wrap your pcm into RF64 wav after the extraction step (i don't recommend to do this - use custom ffmpeg node instead)
-) ask steinar to support the RF64 or BWAV option


Still, i recommend whenever you encounter minor issues with the predefined processor nodes, just use the custom ffmpeg/avisynth or commandline node. This way you are able to fulfull virtually any requirement right away.
Sure it might look like an interesting option to open a feature request for certain problems, but please have in mind that steinar is currently restructuring the whole program instead of implementing new features. Also have in mind that there might be about multiple thousand small features like this one missing. That is whats the custom ffmpeg node and the commandline executor are made for.

The reason for the file being bigger than the duration that certain players will play is that this is the default behaviour of ffmpeg. The file contains all data, but the wav header is only able to carry a duration value for maximum 4GB. So the data is there but the header states that the duration is shorter than it is because it is technically not possible to specify a longer duration. When you load the file into the player, it ignores the file size and instead shows you the duration that is stated in the header.

cheers!
emcodem

Thank you so myuch emcodem...

Hi all,

Thank you emcodem for taking the time to help out splendidly on the forum!

For the next version I will look at supporting wave files > 4GB. Thanks for reporting!

-steinar

Great news steinar