[FFmpeg-devel] Suggested change for encrypted video

[Don Moir]

Carl,

This AVFMT_FLAG_ENCRYPTED requirement started because of a crash I was 
getting on a file that was encrypted. This crash has been reported as being 
fixed.

You can read about the crash on an encrypted file here:

https://avcodec.org/trac/ffmpeg/ticket/495

The above ticket also has a couple links and  attachments for an encrypted 
file.

Still, it's obvious to me, that an application should know if a video is 
encrypted or not, and might fail. The word 'might' may be kind of a loose 
term. I supposed depending on decoder you may not actually know, but maybe 
decoder should be able to provide that info and if it can't decode it then 
just fail the open.

I am not trying to provide a patch. I am trying to suggest at least a flag 
within reason so an app can know if a video is likely to fail decoding. 
Isn't this an obvious thing ?

There could be more details as well that I am not familiar with. So I post 
it here so someone that is more familiar with the internal workings of 
ffmpeg can take a look at this. For example, there may be other likely 
failure states that also need to be flagged.

I opened a ticked on this as an enhancement but really its an omission. That 
ticket is here:

https://ffmpeg.org/trac/ffmpeg/ticket/552

Toward the bottom of that ticket, it is suggested I post it here and thats 
what I did.

We can round and round with it, but I think until at least someone who is 
more familiar with ffmpeg takes a look and does something about it, it will 
remain an omission.

Don Moir

----- Original Message ----- 
From: "Carl Eugen Hoyos" <cehoyos at ag.or.at>
To: <ffmpeg-devel at ffmpeg.org>
Sent: Friday, October 14, 2011 8:20 PM
Subject: Re: [FFmpeg-devel] Suggested change for encrypted video


> Don Moir <donmoir <at> comcast.net> writes:
>
>> Need a new flag in avformat.h
>>
>> #define AVFMT_FLAG_ENCRYPTED 0x80000 ///<Stream is likely encrypted
>
> Please clone current git head as explained on 
> http://ffmpeg.org/download.html
> Then change (and test) the code.
> If you feel unable to use git send-email, use git diff 
>  >patchasfencryption.diff
> and send the patch as an attachment to this list.
>
> Carl Eugen
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel