Em Tuesday 15 January 2008 18:56:35 Laurent Pinchart escreveu:
> Hi Herton,
> 
> On Tuesday 15 January 2008, Herton Ronaldo Krzesinski wrote:
> > Hi Laurent, thanks for the commit and advice. We played with the webcam
> > again (sorry for delay) and we found out that it isn't really reporting the
> > FID bit, but only end of frame marker (EOF). This is strange indeed, as
> > from what I understand from UVC spec FID is required while EOF is optional.
> 
> The bmFramingInfo field in the probe&commit control can be used by the device 
> to report if it supports FID and/or EOF. However, for known frame-based 
> formats, the field must be ignored. Just out of curiosity, could you print 
> the field's value when reading the probe and commit controls ?

It's always 0x00, falls at else in size check inside uvc_get_video_ctrl:
uvc_get_video_ctrl: size != 34, bmFramingInfo = 0x00

> 
> > I reworked the quirk that Claudio made against revision 166 from svn, but
> > now using the EOF to sync the stream (the previous quirk was ok, but on
> > laggy communication, like using to transmit a video stream over internet
> > etc., the frames would overlap etc. resulting in many display issues):
> 
> Your patch could drop the last payload of each frame. Could you please try 
> the 
> attached patch ?

It works, but gives a different behaviour: for example, I simulate lag
in luvcview placing a sleep(1) at the start of uvcGrab function, with
this patch it captures only some frames at start and stops, with the
patch I posted I receive continous snapshots.

> 
> Best regards,
> 
> Laurent Pinchart
> 

-- 
[]'s
Herton
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