[FFmpeg-user] Codec options mapping documentation (was Re: Where can I find ALL options for FFMPEG's FLAC)

Jeff darkmoon at verizon.net
Wed Jun 18 21:30:26 CEST 2014

On Wed, 18 Jun 2014 13:16:01 +0000 (UTC),
Carl Eugen Hoyos <cehoyos at ag.or.at> wrote:

>bart.gopnik <at> gmail.com writes:

>>Where can I find ALL options for FFMPEG's FLAC encoder?

>$ ffmpeg -h full|less
>search for flac

>>I know only "compression_level" option and "-h encoder=flac"
>>command to show FLAC encoder specific options


both 'ffmpeg -h full' and 'ffmpeg -h encoder=xxxxx', so far as I can 
tell, list only the PRIVATE options for the various codecs. What the OP 
is requesting (and what I would sincerely appreciate as well) is 
documentation that describes how the global codec options described in 
section 11 of 'ffmpeg-all.html' map to specific codecs.

In the overview for "11. Codec Options":

  "Sometimes, a global option may only affect a specific kind of codec, 
  and may be unsensical or ignored by another, so you need to be aware 
  of the meaning of the specified options."

This sort of thing may also be found in the descriptions for specific 
codecs, such as "18.4 libx264, libx264rgb":

  "Many libx264 encoder options are mapped to FFmpeg global codec 
  options, while unique encoder options are provided through private 

In order for those of us who are not FFMPEG developers to "...be aware 
of the meaning of the specified options" for each codec, we need 
documentation. For example:

On Wed, 18 Jun 2014 15:03:33 +0200, James Darnley wrote:

>On 2014-06-18 13:52, bart.gopnik <at> gmail.com wrote:

>>1. How to know minimum and maximum values of "compression_level" 

>Unfortunately only by reading the source code. Though I can tell you 
>that it supports 0-12.

So, the only way to know the values for "compression_level" that the 
flac encoder supports is to read the source code, or hope it may be 
found in the mailing list archives?

FFMPEG is a terrific tool, and it gets better all the time. However, 
it is also a complex tool because it can do so much. Is there nowhere 
we can find the details we need to make it work short of asking on the 
mailing list and searching the list archives?



More information about the ffmpeg-user mailing list