I am using an 8 megapixel camera and when I set the resolution to 3264x2448 i get the following:
libv4l2: error converting / decoding frame data: v4l-convert: error destination buffer too small (16777216 < 23970816) VIDIOC_DQBUF: Bad address
Hi, Yes I´m doing this. I´m using a 8MP USB3 Cam with Ubuntu 12.04.
You have to Edit the source of lib v4l. The problem ist the call of v4l2_read_and_convert(,..,..., int maxsize). There is a defined max size (16777216), if you change this to > 23970816 it will work.
I´m sorry that i actually couldn´t give you the File where to edit the value.
Actually, this should be reported as a bugfix. If you get the time, please visit the http://code.opencv.org/projects/opencv/wiki/How_to_contribute">how to contribute page. This should be noted down and maybe by adding an extra parameter, this can be solved. I think it was originally to make sure the size wasn't larger than possible to store in memory.
I have found the code for libv4l2 recompiled and found the issue. I have actually entered this as bug on opencv with notes of the fix on the libv4l2 tip.
had made a change to http://git.linuxtv.org/v4l-utils.git/tree tip in file v4l-utils-HEAD-4dea4af/lib/libv4l2/libv4l2-priv.h The change was define V4L2_FRAME_BUF_SIZE (4096 * 4096)
to
When the package is recompiled and then the shared object files updated the package now works with the 8 megapixel camera in the raw mode.
What action do you want me to take or maybe you have more insight into the how this is to work?
I am in contact with libv4l2 person now [email protected] and have passed my fix plus the problem description. We can see what response we get.
Asked: 2013-12-10 13:08:19 -0600
Seen: 930 times
Last updated: Dec 11 '13
