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4cd9255f0a
Make sure we always call munmap() with the same size we called mmap() with before. Current v4l2src uses the same structure for VIDIOC_QUERYBUF, VIDIOC_QBUF and v4l2_munmap calls. The problem is that the video buffer size (length) may vary for compressed or emulated bufs. VIDIOC_QBUF will change it if we pass the pointer of a v4l2_buffer. This is why we should avoid using same variable for mmap and video buffers. https://bugzilla.gnome.org/show_bug.cgi?id=671126 |
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| .. | ||
| .gitignore | ||
| gstv4l2.c | ||
| gstv4l2bufferpool.c | ||
| gstv4l2bufferpool.h | ||
| gstv4l2colorbalance.c | ||
| gstv4l2colorbalance.h | ||
| gstv4l2object.c | ||
| gstv4l2object.h | ||
| gstv4l2radio.c | ||
| gstv4l2radio.h | ||
| gstv4l2sink.c | ||
| gstv4l2sink.h | ||
| gstv4l2src.c | ||
| gstv4l2src.h | ||
| gstv4l2tuner.c | ||
| gstv4l2tuner.h | ||
| gstv4l2vidorient.c | ||
| gstv4l2vidorient.h | ||
| gstv4l2xoverlay.c | ||
| gstv4l2xoverlay.h | ||
| Makefile.am | ||
| README | ||
| v4l2_calls.c | ||
| v4l2_calls.h | ||
| v4l2src_calls.c | ||
| v4l2src_calls.h | ||
v4l2 plugins
============
The idea is a bit the same as the idea for the v4l1 plugins. We want
one generic v4l2element, and a few child objects (probably only two:
v4l2src and v4l2sink):
/-------- v4l2src
v4l2element ---=
\-------- v4l2sink
Both v4l2src and v4l2sink have a uncompressed and a compressed
recording-/playback-mode. Since this is all part of v4l2, the 'client'
of these elements, i.e. an application using v4l2src/v4l2sink, will
hardly notice this. All capsnego stuff is done inside, and the plugin
knows which formats are compressed and which are not.
Please note that the v4l1 and the v4l2 plugins are *not* compatible
concerning properties. Naming has been kept the same where possible,
but in some cases, properties had to be removed or added to make
full use of v4l2.
V4L2 API: http://linux.bytesex.org/v4l2/.
http://v4l2spec.bytesex.org/
/usr/include/linux/videodev2.h or
Kernel patches available from
http://dl.bytesex.org/patches/.
Articles:
http://lwn.net/Articles/203924/