[FFmpeg-user] Does v360 filter support dewarping circular fisheye images?

[Michael Koch]

Am 24.12.2020 um 13:51 schrieb Paul B Mahol:
> On Thu, Dec 24, 2020 at 12:25 PM Michael Koch <astroelectronic at t-online.de>
> wrote:
>
>> Am 24.12.2020 um 10:42 schrieb thongtm2:
>>> I have a fisheye camera (360 degrees in horizontal & 180 degrees in
>>> vertical). Is it possible to use v360 filter to dewarp circular fisheye
>>> images to single perspective images (flatten fisheye images)? I've tried
>>> many options but the results were not as I expected. Below command is
>> one of
>>> them:
>>>    ffplay fisheye_video.mp4 -vf
>>> v360=fisheye:ih_fov=360:iv_fov=180:flat:yaw=120:pitch=0:roll=0
>> There are several problems in your command line.
>> 1. As Paul has already pointed out, ih_fov and iv_fov must have the same
>> value for fisheye input. In your case both must be 180.
>> 2. It also makes sense to specify the output field of view h_fov and
>> v_fov and the output size w and h, because the default values aren't
>> known (unless you look in the source code).
>> 3. The command line is better readable if you don't omit the names of
>> the options. I mean "output=flat". The names can be omitted if the
>> options are specified exactly in the correct order. Your command line
>> may work as it is, but it would be better if "flat" or "output=flat" is
>> the second option.
>>
>> This should work:
>>
>> v360=input=fisheye:output=flat:ih_fov=180:iv_fov=180:h_fov=90:v_fov=60:w=900:h=600:pitch=-60
>>
>>
> I may be mistaken, but OP input looks to be 360 fisheye, I havent actually
> tried.

May be. As I understood it, he has a normal fisheye lens which is 
pointing up to the sky. Then he has 360° around the horizon (which is 
the edge of the image circle) and the image diameter is 180°.

Michael