What are the actual supported framerate/resolution pairs for the PBP webcam?

[gleachkr]

Here's something I'd like to know. What are the actual supported framerates/resolution pairs for the pinebook pro's webcam?

v4l2-ctl --list-formats-ext gives

Code:

ioctl: VIDIOC_ENUM_FMT
    Type: Video Capture

    [0]: 'YUYV' (YUYV 4:2:2)
        Size: Discrete 1280x720
            Interval: Discrete 0.100s (10.000 fps)
            Interval: Discrete 0.200s (5.000 fps)
        Size: Discrete 1600x1200
            Interval: Discrete 0.050s (20.000 fps)
            Interval: Discrete 0.067s (15.000 fps)
        Size: Discrete 640x480
            Interval: Discrete 0.050s (20.000 fps)
            Interval: Discrete 0.067s (15.000 fps)
            Interval: Discrete 0.100s (10.000 fps)
            Interval: Discrete 0.200s (5.000 fps)
        Size: Discrete 320x240
            Interval: Discrete 0.050s (20.000 fps)
            Interval: Discrete 0.067s (15.000 fps)
            Interval: Discrete 0.100s (10.000 fps)
            Interval: Discrete 0.200s (5.000 fps)
        Size: Discrete 800x600
            Interval: Discrete 0.100s (10.000 fps)
            Interval: Discrete 0.200s (5.000 fps)

which suggests that the camera is capable of a pretty good framerate at 1600x1200. But I haven't figured out how to actually achieve this frame rate at this resolution. The higher resolution seems to default to quite long exposures, which might have something to do with it, although setting absolute exposure manually affects brightness but doesn't seem to effect the "blur" effect that the long exposures create.

Testing with external webcams tentatively suggests that the bottleneck isn't the power of the pbp---you can get smooth 30fps playback of the video feed there, in the same output format (YU12-YU12, according to guvcview, although maybe there's some subtle thing here that I'm missing) that the pbp's camera produces.

Anyway I'm just very curious about 1. what the actual capacities of this camera are, and 2. whether we might hope to see better fps at high resolution in the future, with better driver support, or with the right software configuration.

[Arwen]

Whence you figure it out, please update the Wiki page;

https://wiki.pine64.org/index.php?title=...Pro#Webcam

Or let me know, and I will update the Wiki page.

One limitation is the USB 2 bus. If I remember correctly, the SoC's USB 2 port has a USB hub attached, with both the internal keyboard, (with trackpad), and the Web Camera on it. Not saying we can't get 20 fps, just saying the port is shared, so it's possible that heavy trackpad use would disrupt the Web Camera.

[xmixahlx]

i found 640x480 to be the only barely acceptable choice. i have an external webcam and didnt play with it much, however.