[AG-TECH] Problem with firewire camera and H261 video producer
c.willing at uq.edu.au
Thu Apr 2 17:43:02 CDT 2009
On 03/04/2009, at 8:29 AM, Christoph Willing wrote:
> On 03/04/2009, at 7:35 AM, Douglas Kosovic wrote:
>> Hi Steve,
>>> I am setting up a small AG node with 3.1 on Ubuntu Hardy. I have
>>> a Unibrain Fire-i firewire camera. I can use vloopback and
>>> dc1394_vloopback to get a nice 320x240 or 640x480 stream with the
>>> H.264 video producer, but the older H.261 does not work, giving me
>>> odd patterns of mostly green diagonal lines.
>>> I read somewhere that VIC expects RGB 16 bits per pixel. This may
>>> be my problem since the firewire setup offers only RGB 24 bit, YUV
>>> 422, YUV422p, and YUV420p. I could modify dc1394_vloopback to
>>> convert the video, but is there an easier way?
>> VIC's V4L2 grabber supports YUV422, YUV422P, YUV420P, MJPEG and
>> JPEG pixel formats.
>> VIC's V4L grabber supports YUV422, YUV422P and YUV420P pixel formats.
>> The preferred format for H.261 and H.264 would be YUV420P as that's
>> what the codecs use.
>> The issue with the H.261 codec is that it only supports the
>> traditional video conferencing resolutions of CIF (352x288) and
>> QCIF (176x144), so will pad with a black border (or gray if older).
>> If you can run vic on the command-line, e.g.:
>> vic 220.127.116.11/15000
>> select the device and transmit, then copy the console output, that
>> would be handy for me to tell what's going wrong.
>> I suspect your version of VIC is using an earlier broken V4L2
>> grabber code.
> If the OP is using latest vic for hardy, then its derived from UCL
> repo 13th Jan 2009. Has there been any significant change to V4L2
> grabber code since then?
One other thing,
The same vic is used for h264 as for h261 so the vic version can't be
Christoph Willing +61 7 3365 8316
QCIF Access Grid Manager
University of Queensland
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