2009-07-15 22:22:57     how to debug v4l device cmos camera

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2009-07-15 22:22:57     how to debug v4l device cmos camera


Message: 77413   




Earlier, I was atleast able to get mis-colored images in a vlc player on my client side using the method described here -   docs.blackfin.uclinux.org/doku.php?id=uclinux-dist:ffmpeg (the miscolor is due to my hardware issue of broken track in data line of the cmos camera.)


But now (after a month of break and running svn update yesterday)  i get the following error on my custom board -




"> ffmpeg -f video4linux -s 320x240 -i /dev/video0 -f mpegts udp:192.168.1.


FFmpeg version SVN-r8498, Copyright (c) 2000-2007 Fabrice Bellard, et al.     

  configuration: --prefix=/usr --source-path=/home/vivek/bfin/uclinux-dist/lib/-

  libavutil version: 49.5.0                                                   

  libavcodec version: 51.48.0                                                 

  libavformat version: 52.1.0                                                 

  built on Jul 14 2009 22:38:41, gcc: 4.1.2 (ADI svn)                         

[video4linux @ 0x34081c]VIDIOCGCAP: Invalid argument                          

/dev/video0: I/O error occured                                                

Usually that means that input file is truncated and/or corrupted.




It is possible that I might have messed up in hardware, but I am wondering if something else in the V4L driver changed because till yesterday i was stuck with a problem due to such a change- which is now fixed by svn-   blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=5241


I was wondering if there is a change in v4l related to/around VIDIOCGCAP or should i look into my hardware ?


Otherwise how can i try to capture a frame from /dev/video0 without using ffmpeg.


/dev/video0 exists but I dont know how i check its validity further.


Thank you,







2009-07-15 22:38:15     Re: how to debug v4l device cmos camera

Mike Frysinger (UNITED STATES)

Message: 77414   


you're probably better off trying to get 2009R1 working rather than trunk




2009-08-05 00:02:29     Re: how to debug v4l device cmos camera


Message: 78379   


Thanks Mike,  2009R1 works.


So now either i made a wrong/different selection in menuconfig, that svn shows this issue to me, or there is some code difference in svn.


will try to look for difference in selection on my side, and update this thread.