[FFmpeg-user] FFplay, wrong output size on extended desktop

Michael Koch astroelectronic at t-online.de
Thu May 26 09:12:31 EEST 2022

Am 25.05.2022 um 21:32 schrieb Gyan Doshi:
> On 2022-05-25 08:31 pm, Michael Koch wrote:
>> Hello,
>> we want to use FFplay in a planetarium. It's a Windows computer with 
>> an extended desktop. The left monitor contains the user interface 
>> (1920x1080) and at the right side is a 4Kx4K extended desktop, which 
>> is shown on two 4096x2048 monitors, upper half and lower half. The 
>> extended 4Kx4K desktop is mirrored to the dome with 11 projectors.
>> We are using this 4Kx4K test image:
>> http://www.paulbourke.net/dome/testpattern/4096.png
>> This is the FFplay command line:
>> ffplay -noborder -left 1920 -top 0 4096.png
>> The problem is that the image is shown twice as large as it should 
>> be, so that we see only the top left quadrant.
>> You can see a screenshot in this discord channel (in german language):
>> https://discord.com/channels/968113228230045706/968113812769210398
>> If we set the size to 2048x2048, then the output is 4096x4096:
>> ffplay -noborder -x 2048 -y 2048 -left 1920 -top 0 4096.png
>> But then we don't have the full 4K resolution.
>> Who has an idea what's wrong here?
>> The console output is below.
> What's the size value in Settings -> Display under Scale and Layout?

Problem solved. Scale was set to 200%.


More information about the ffmpeg-user mailing list