[FFmpeg-user] Documentation for input -i options

[Gyan]

On 05-12-2019 09:00 pm, John Dexter wrote:
> On Thu, 5 Dec 2019 at 15:23, Gyan <ffmpeg at gyani.pro> wrote:
>
>>
>> On 05-12-2019 08:44 pm, John Dexter wrote:
>>> Bizarrely am struggling to find a thorough documentation of -i and
>> relying
>>> on examples online. Can anyone point me where in the online documentation
>>> this is documented (not a man page) please? I know it supports
>>> patterns e.g. for timelapse but I cannot find a reference.
>> All -i does is specify the input URL. Which options are applicable for
>> an input is determined by
>> the input format / codecs discovered by ffmpeg after probing the input.
>>
>> What specifically are you trying to do?
>>
> Time-lapse from a whole bunch of images. I've found examples online of
> syntax I can use but no explanation exactly how this is working and how
> flexible this is.
> e.g. -i image%8d
> I'd like to know how I can specify which files are used and in which order.
> Maybe my question is where is the input URL functionality documented?

For a sequence of images, the input URL serves as a pattern which is 
interpreted by the image sequence demuxer (image2).
See ffmpeg -h demuxer=image2 to see its options, or on the web at 
http://ffmpeg.org/ffmpeg-formats.html#image2-1
On linux, you should also have access to globbing support.

Gyan