[FFmpeg-user] Streaming h264/mpeg4 being written to disk, header is at the end?

ethan at 757.org ethan at 757.org
Wed Aug 1 07:01:25 CEST 2012

Howdy everyone!

I've been toying around with trying to use ffmpeg server and streaming.

I have a unit that writed h264/mpeg4 video to disk, already hardware 
encoded (Blackmagic Designs ATEM Television Studio.)

At first I thought I could write it to network attached storage, and open 
the file from players such as VLC. No go.

It turns out what I would call the header is written at the end of the 
file by the Blackmagic unit's software.

The minute the file is closed players have no issue. Before I understood 
that the information about the streams in the file were at the end, I was 
trying netcat and tail and all sorts of hacks.

Is there a way to tell ffmpeg what kind of video is there (overriding the 
need for the information in the file as I can predict what it will be), 
and use it to read the data being written before the footer is there and 
forward this off to a streaming server?

The unit's hardware encoding capabilities deliver full 1920x1080 
h264/mpeg4, just no ability to stream. Tried using a HDMI capture card but 
it's stupid trying to run a huge computer to re-do what is being done 

Any help is greatly appreciated!

Ethan O'Toole
757 Labs Hackerspace    : www.757labs.org

More information about the ffmpeg-user mailing list