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transposing a video from horizontal to vertical

Wife got ALS challenge and I took a video of her drenching in ice using iphone. The only issue was the somehow I tilted the phone while taking it and it came horizontal. If it was an image then many image editors will transpose it for you.

Now challenge is that I cant ask her to drench in ice again so instead of her getting mad at me to ruin her video (yaa I know the Facebook generation needs everything to be perfect if its posted on Facebook).  So now I need to transpose it, it seems you can do it using ffmpeg in ubuntu.

First try was using

ffmpeg -i ~/Desktop/IMG_0888.MOV -vf "transpose=1" -r 30 -sameq -acodec copy ~/Desktop/test.MOV

but a 90MB file became 350MB which would be impossible to post on FB in 1 hour.

So I gave a second try using

ffmpeg -i ~/Desktop/IMG_0888.MOV -vf "transpose=1" -b 25000000 -sameq -acodec copy ~/Desktop/test1.MOV

where some site said you take 1G and divide it by your no of seconds in video and that would be the bit rate you give in -b



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