Ability to get unknown resolutaion, if there is no other.

[ArtemProkopenko]

Hello and thank for this super tool.

I have some problem. Show by example:

youtube-dl http://ru.xhamster.com/movies/961153/ass.html -o '/tmp/test.%(ext)s'  -F
[XHamster] 961153: Downloading webpage
[XHamster] 961153: Downloading HD webpage
[info] Available formats for 961153:
format code  extension  resolution note
sd           mp4        unknown  
youtube-dl http://ru.xhamster.com/movies/961153/ass.html -o '/tmp/test.%(ext)s' -f 'best[width<=640]'
[XHamster] 961153: Downloading webpage
[XHamster] 961153: Downloading HD webpage
ERROR: requested format not available

Such cases are very rare, but if it happened, I would prefer to receive video with unknown resolutaion. Is it possible (in automatic mode course - in only one command)?

[phihag]

Pass in -f 'best[width<=?640]'.

[ArtemProkopenko]

Thank!