gstreamer/subprojects/gst-plugins-good/sys/v4l2
Philipp Zabel 7ae6c203cb v4l2: bufferpool: Drop writable check on output pool process
Output buffers don't have to be writable. Accepting read-only buffers
from the V4L2 buffer pool allows upstream elements to write directly
into the V4L2 buffers without triggering a CPU copy into a new buffer
from the same V4L2 buffer pool every time.

Tested with the vivid output device:

  GST_DEBUG=GST_PERFORMANCE:7 gst-launch-1.0 videotestsrc ! v4l2sink device=/dev/video5

With this change, gst_v4l2_buffer_pool_dqbuf() must be allowed to not
resize read-only memories of output buffers.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/6648>
2024-04-16 08:15:16 +00:00
..
ext v4l2: Sync headers to current media_stage 2023-06-15 14:32:32 +00:00
gstv4l2.c Replace gst-i18n-*.h with gi18n-lib.h 2022-04-19 18:01:06 +00:00
gstv4l2allocator.c v4l2: allocator: Fix unref log/trace on memory release 2024-04-06 23:41:52 +00:00
gstv4l2allocator.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2bufferpool.c v4l2: bufferpool: Drop writable check on output pool process 2024-04-16 08:15:16 +00:00
gstv4l2bufferpool.h v4l2: pool: Flush events on capture queue 2023-05-01 15:08:10 -04:00
gstv4l2codec.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2codec.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2colorbalance.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2colorbalance.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2deviceprovider.c v4l2: device provider: Fix GMainLoop leak 2023-05-03 10:04:58 +00:00
gstv4l2deviceprovider.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2element.c Replace gst-i18n-*.h with gi18n-lib.h 2022-04-19 18:01:06 +00:00
gstv4l2elements.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2fwhtenc.c Replace gst-i18n-*.h with gi18n-lib.h 2022-04-19 18:01:06 +00:00
gstv4l2fwhtenc.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2h263enc.c Replace gst-i18n-*.h with gi18n-lib.h 2022-04-19 18:01:06 +00:00
gstv4l2h263enc.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2h264codec.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2h264codec.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2h264enc.c Replace gst-i18n-*.h with gi18n-lib.h 2022-04-19 18:01:06 +00:00
gstv4l2h264enc.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2h265codec.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2h265codec.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2h265enc.c Replace gst-i18n-*.h with gi18n-lib.h 2022-04-19 18:01:06 +00:00
gstv4l2h265enc.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2jpegenc.c Replace gst-i18n-*.h with gi18n-lib.h 2022-04-19 18:01:06 +00:00
gstv4l2jpegenc.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2mpeg2codec.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2mpeg2codec.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2mpeg4codec.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2mpeg4codec.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2mpeg4enc.c Replace gst-i18n-*.h with gi18n-lib.h 2022-04-19 18:01:06 +00:00
gstv4l2mpeg4enc.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2object.c v4l2: enforce a pixel aspect ratio of 1/1 if no data are available 2024-04-07 14:17:19 +01:00
gstv4l2object.h v4l2object: scale the encoded sizeimage based on maximum resolution 2023-10-23 14:10:56 +00:00
gstv4l2radio.c Replace gst-i18n-*.h with gi18n-lib.h 2022-04-19 18:01:06 +00:00
gstv4l2radio.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2sink.c v4l2: Fix SIGSEGV on 'change state' during 'format change' 2022-12-01 12:47:54 +00:00
gstv4l2sink.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2src.c v4l2src: need maintain the caps order in caps compare when fixate 2024-03-28 20:05:27 +00:00
gstv4l2src.h v4l2src: Add support for cropping at capture source input 2022-03-11 15:02:08 +00:00
gstv4l2transform.c gst-plugins-good: re-indent with GNU indent 2.2.12 2023-03-17 03:18:54 +00:00
gstv4l2transform.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2tuner.c gstv4l2tuner: return NULL if no norm set 2022-02-20 21:38:40 +00:00
gstv4l2tuner.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2videodec.c v4l2videodec: Correctly free caps to avoid memory leak 2023-09-24 12:50:01 +00:00
gstv4l2videodec.h v4l2: videodec: Don't forcibly drain on resolution changes 2023-05-01 13:44:53 -04:00
gstv4l2videoenc.c v4l2videoenc: unconditionally activate the OUTPUT pool 2023-10-11 19:35:54 +00:00
gstv4l2videoenc.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2vidorient.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2vidorient.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2vp8codec.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2vp8codec.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2vp8enc.c Replace gst-i18n-*.h with gi18n-lib.h 2022-04-19 18:01:06 +00:00
gstv4l2vp8enc.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2vp9codec.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2vp9codec.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
gstv4l2vp9enc.c Replace gst-i18n-*.h with gi18n-lib.h 2022-04-19 18:01:06 +00:00
gstv4l2vp9enc.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
meson.build meson: Add a wrap file for libgudev 2023-04-19 22:47:19 +00:00
README Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
tuner.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
tuner.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
tunerchannel.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
tunerchannel.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
tunernorm.c Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
tunernorm.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
v4l2-utils.c v4l2: drop use of GSlice 2023-01-24 15:25:07 +00:00
v4l2-utils.h Move files from gst-plugins-good into the "subprojects/gst-plugins-good/" subdir 2021-09-24 16:13:50 -03:00
v4l2_calls.c v4l2: Change to query only up to V4L2_CID_PRIVATE_BASE+V4L2_CID_MAX_CTRLS 2023-06-13 13:04:37 +00:00

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/