ROI bug or expected behaviour

[gagle]

Code: Select all

/opt/vc/bin/raspivid -o vid.h264 -w 640 -h 480 -t 2000 --roi 0.5,0.0,1.0,1.0

1.jpg (29.68 KiB) Viewed 1132 times

There's a white line in the right edge.

PD: I don't understand how the parameter it's supposed to work. 0.5,0.0,1.0,1.0 from my understanding should be the same as 0.5,0.0,0.5,0.5 if we want to maintain the aspect ratio, that is, the upper right corner.

[jamesh]

It's a normalised coordinate system. Assume 1.0 is full frame width, so 0.25 would be half a frame width.

So 0.5,0.5,1.0,1.0 is actually a full frame starting at the middle of the frame, which will actually be clipped to the frame edge, so is the same as 0.5,0.5,0.5,0.5

Done like this so when you change frame size the ROI parameters don't need to be adjust to get the same result.

[gagle]

And the white edge? It is something about the rounding up to the nearest multiple of 32? 640*0.5 = 320, multiple of 32, so...

[jamesh]

And the white edge? It is something about the rounding up to the nearest multiple of 32? 640*0.5 = 320, multiple of 32, so...

No idea. Maybe.