[FFmpeg-user] multiple drawtext parameters

[Stefano Sabatini]

On date Friday 2011-05-27 06:14:20 -0700, mromey encoded:
> Want to use ffmpeg to publish quickTimes and thumbnails for our asset
> management system.  Evaluating how viable ffmpeg would be as a replacement
> to our current system.  In the past I have done it lots of different ways. 
> I have used After Effects, Nuke, RVIO, python and pil.  Thus far I am
> impressed with ffmpeg but having some difficulty with some parameters.  
> Exploring the drawtext filter.  I have the following example.
> 
> ffmpeg.exe -i C:/temp/input.mov -vf drawtext="arial.ttf=':text='TEST'"
> C:/temp/output.mov
> 
> Have a few questions:
> 
> 1.  Is it possible to process multiple drawtext in the same IO stream.  I
> would rather load the movie or image sequence once into memory once then
> apply each drawtext overlay rather than process the addition of each
> drawtext and load the file each time.  If this is possible can somebody help
> by showing me the syntax.

You can put different drawtext filter in sequence:
-vf drawtext=text="text1",drawtext=text="text2",...

> 2.  One of the drawtext burn ins needs to be a frame counter.  Is it
> possible to send some type of internal variable/flag to the value of text
> that would use the frame number in lieu of static text?

It is possible but we have yet to find a syntax for doing it in an
extensible way.

> 3.  Was hoping to get some direction as to how I would take a single frame
> slate file and append it to a quicktime via ffmpeg.

That would be a concatenation filter, yet to be
implemented/integrated, patches are welcome, in alternative file a
feature requests (and sponsorships are welcome as well).
 
> Thanks for the help in advanced.