How to demerge a mixed recovered file?

[Saeed Iranzad]

Hi

I have some files recovered as pdf.

But actually they are not just pdf or not pdf at all.

One of them can be heard by media players!

I extracted an audio file from it and now I want to recover the pdf from the rest of it.

How to understand what type is a file genuinely?

I have some pdf files which are not opened.

[DennisD]

Hi Saeed, and welcome to the forum.

 

You appear to have recovered a mixed up (corrupt) video file.

 

A video file such as avi, mp4, is simply a container containing a separate video and audio file, and in this case unfortunately it appears that the container has been recovered containing a pdf and an audio file. Pretty mixed up probably by being partially overwritten or fragmented on the drive.

 

Recovering the audio file has been possible because demuxing utilities are hard wired to look for and extract either a recognized video or audio file.

 

I don't know if software will exist to extract a pdf from such a "container". They will just not recognize the pdf file as audio or video.

 

That's my take on it Saeed based upon my own experience of separating and merging (demuxing and muxing) audio and video files, and unfortunately I've never came across anything to do what you're asking. It wouldn't be possible I believe to even put a pdf and audio file together for testing.

 

If others have anything more positive, I'm sure they'll contribute.

 

Sorry I couldn't help.