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https://gitlab.freedesktop.org/gstreamer/gstreamer.git
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116649371e
Most V4L2 ioctls like try_fmt will adjust input fields to match what the hardware can do rather then returning -EINVAL. As is docmented here: http://linuxtv.org/downloads/v4l-dvb-apis/vidioc-g-fmt.html EINVAL is only returned if the buffer type field is invalid or not supported. So upon requesting V4L2_FIELD_NONE devices which can only do interlaced mode will change the field value to e.g. V4L2_FIELD_BOTTOM as only returning half the lines is the closest they can do to progressive modes. In essence this means that we've failed to get a (usable) progessive mode and should fall back to interlaced mode. This commit adds a check for having gotten a usable field value after the first try_fmt, to force fallback to interlaced mode even if the try_fmt succeeded, thereby fixing get_nearest_size failing on these devices. https://bugzilla.gnome.org/show_bug.cgi?id=735660 |
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|---|---|---|
| .. | ||
| ext | ||
| gstv4l2.c | ||
| gstv4l2allocator.c | ||
| gstv4l2allocator.h | ||
| gstv4l2bufferpool.c | ||
| gstv4l2bufferpool.h | ||
| gstv4l2colorbalance.c | ||
| gstv4l2colorbalance.h | ||
| gstv4l2deviceprovider.c | ||
| gstv4l2deviceprovider.h | ||
| gstv4l2object.c | ||
| gstv4l2object.h | ||
| gstv4l2radio.c | ||
| gstv4l2radio.h | ||
| gstv4l2sink.c | ||
| gstv4l2sink.h | ||
| gstv4l2src.c | ||
| gstv4l2src.h | ||
| gstv4l2transform.c | ||
| gstv4l2transform.h | ||
| gstv4l2tuner.c | ||
| gstv4l2tuner.h | ||
| gstv4l2videodec.c | ||
| gstv4l2videodec.h | ||
| gstv4l2vidorient.c | ||
| gstv4l2vidorient.h | ||
| Makefile.am | ||
| README | ||
| tuner.c | ||
| tuner.h | ||
| tunerchannel.c | ||
| tunerchannel.h | ||
| tunernorm.c | ||
| tunernorm.h | ||
| v4l2-utils.c | ||
| v4l2-utils.h | ||
| v4l2_calls.c | ||
| v4l2_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/