Date: Wed, 01 Jun 2011 14:25:05 +0400 From: Boris Samorodov <bsam@ipt.ru> To: Hans Petter Selasky <hselasky@c2i.net> Cc: freebsd-multimedia@freebsd.org Subject: Re: Pre-release of webcamd [v0.2.4] Message-ID: <23778750@bb.ipt.ru> In-Reply-To: <201106011150.13316.hselasky@c2i.net> (Hans Petter Selasky's message of "Wed, 1 Jun 2011 11:50:13 %2B0200") References: <201105240020.49377.hselasky@c2i.net> <201105311932.38205.hselasky@c2i.net> <45215846@bb.ipt.ru> <201106011150.13316.hselasky@c2i.net>
next in thread | previous in thread | raw e-mail | index | archive | help
Hi, On Wed, 1 Jun 2011 11:50:13 +0200 Hans Petter Selasky wrote: > On Wednesday 01 June 2011 11:41:13 Boris Samorodov wrote: > > Running: > > ----- > > % pwcview > > Webcam set to: 320x240 (sif) at 5 fps # OK (shaky, but it's 5 fps) > > % pwcview -f 30 > > Webcam set to: 320x240 (sif) at 30 fps # shaky video, (5 fps?) > > % pwcview -s vga > > Webcam set to: 640x480 (vga) at 5 fps # seems to use 30 fps > > % pwcview -s vga -f 5 > > Webcam set to: 640x480 (vga) at 5 fps # seems to use 30 fps > > ----- > > > > Thanks! > Hi, > The shakyness I'm not sure if my english is good here. When I say "shaky" it means that video is stable (fixed) for some moments, than changes and stable again. But it's OK for the first command since 5 fps is the default according to PWCVIEW(1) and video changes about 5 times per second. The problem is with the second video which should change 30 times per second. It does not. And I'm not sure that a buffer change may help here since I get good vga (-s vga) video with 30 fpc (i.e. existing buffers allows it). The next problem is that just with the option "-s vga" the resulting fps should be 5 (the default). But I get a good 30 fps video. And the last problem is that adding "-f 5" to "-s vga" option does not result in 5 fps video -- I get good 30 fps video! > I think can be fixed by increasing the buffer size used by UVC > video driver, it is currently very small, only 2*7ms: > Index: patches/uvcvideo.h.diff > =================================================================== > --- patches/uvcvideo.h.diff (revision 1788) > +++ patches/uvcvideo.h.diff (working copy) > @@ -8,7 +8,7 @@ > +#define UVC_URBS 2 > /* Maximum number of packets per URB. */ > -#define UVC_MAX_PACKETS 32 > -+#define UVC_MAX_PACKETS 56 > ++#define UVC_MAX_PACKETS (8*16) /* ms/8 for HighSpeed */ > /* Maximum number of video buffers. */ > #define UVC_MAX_VIDEO_BUFFERS 32 > /* Maximum status buffer size in bytes of interrupt URB. */ However I tested the patch with webcamd 0.1.26 (just editted by hand the existing patch, rebuild/reinstall webcamd, replug my cam). Nothing has changed. > This value should be dynamic depending on various factors like device speed > and endpoint configuration. I have found any time yet to make the change. -- WBR, Boris Samorodov (bsam) Research Engineer, http://www.ipt.ru Telephone & Internet SP FreeBSD Committer, http://www.FreeBSD.org The Power To Serve
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?23778750>