[FFmpeg-user] specifying by "100m"

Michael Bradshaw mbradshaw at sorensonmedia.com
Wed Aug 15 23:59:33 CEST 2012

On Wed, Aug 15, 2012 at 3:50 PM, Michael Bradshaw
<mbradshaw at sorensonmedia.com> wrote:
> [trimming quoting of the ffmpeg mailing list sig]
> On Wed, Aug 15, 2012 at 3:40 PM, Dan M <dan at streemit.net> wrote:
>> On 08/15/2012 04:27 PM, Roger Pack wrote:
>>>> I dunno if this makes a difference, but did you try "1M"? In metric
>>>> prefixes, m = milli (10^-3), but M = mega (10^6). I'm not sure if
>>>> ffmpeg takes this into account or not, but it's worth checking.
>>> That does appear to work, thanks.
>>> I guess I didn't know that in metric little "k" means kilo but big M
>>> means mega. Weird.
>>> -roger-
>> Actually the proper metric suffix for thousands is cap K, but using little k
>> is popular and is doesn't interfere with the divide-by suffix so it's
>> allowed more often than not.
> Actually, it's little k. See http://physics.nist.gov/cuu/Units/prefixes.html

Or if you want a really official source, see NIST Special Publication
330, 2008 Edition at http://physics.nist.gov/Pubs/SP330/sp330.pdf

Or for a non-US version, the prefixes agreed upon in Resolution 12 at
the 11th Conférence Générale des Poids et Mesures at
http://www.bipm.org/en/CGPM/db/11/12/ (full PDF of the official
current SI brochure can be found at
(particularly, see page 121)).

Sorry, I just got interested in this stuff :)


More information about the ffmpeg-user mailing list