[FFmpeg-user] ffplay at half size by means of a math function

[Jim Shupert]

On 6/30/2015 3:25 PM, Dave P wrote:
> On Jun 30, 2015 11:32 AM, "Jim Shupert, Jr." <jshupert at theppsgroup.com>
> wrote:
>>
>>
>> Friends,
>>
>> I wish to be able to play a file with ffplay but have it play at 1/2 the
>> real size
>>
>> with -x NUM  -y NUM
>> I can control play size with
>> ffplay -x 640 -y 360 -i dog.avi
>> this works as hoped
>>
>> but what I would really like to do is do some math on the file and scale
>> it down
>>
>>
>> with something like
>> ffplay -vf=scale=iw/2:ih/2 -i /media/data/zzz-s/NASA_logo.mov
> You need a blank space after -vf
>
> -vf scale=
oh my - that is humbling . Thank you dave P

here is what i settled on. it works

ffplay -vf "scale=iw/2:ih/2" -i /media/data/zzz-s/NASA_logo.mov