Some v4l2 drivers don't have the capacity to change framerate. There is
chance to make decoder capture fps to be 0/0 if numerator and denominator
returned by G_PARM ioctl are both 0. It causes critical warning
"passed '0' as denominator for `GstFraction'".
In order to fix this, add protection when set decoder capture fps according
to output fps.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/1048>
skip_try_fmt_probes is set to TRUE for v4l2src to skip interlace-mode and
colorimetry when probe caps. gst_v4l2_object_set_format_full() will add
colorimetry back to caps when iterating over the negotiated caps. There is
one case that v4l2src is first in preview state then starts recording.
v4l2src caps will change with an additional interlace-mode structure after
renegotiation, then v4l2src needs to reset. But this camera driver can't
orphan buffer pool, it causes require buffer failed as streaming is still
in active state.
To fix this, also need to add interlace-mode back to caps for camera to
avoid reset.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/961>
Some streams have unknown colorimetry in caps, but v4l2object sets
default values for each primaries. It will cause check colorimetry
fail when do gst_v4l2_video_colorimetry_matches().
To fix this, need to keep the unknown colorimetry in caps same as
the default value set by v4l2object.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/923>
video-info sets gst colorimetry to default value when colorimetry in caps
is unparsable or invalid. Then v4l2object uses this gst colorimetry to do
mapping with v4l2 colorimetry. This may cause colorimetry mismatch when
check mapped gst colorimetry with that read from caps directly.
To fix this, need to correct gst colorimetry as that parsed from video-info
when check gst_v4l2_video_colorimetry_matches().
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/917>
For legacy drivers that don't implement ENUM_FRAMESIZE, use active
resolution to probe colorspace. This can improve the accuracy of the
result when the colorspace depends on the resolution. This fixes a
wrong colorspace issue on board with vendor bsp at resolution 2560x1440.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/830>
gst_v4l2_open() is called by gst_v4l2_device_provider_probe_device(),
where the GstV4l2Object is created without an associated GstElement.
If gst_v4l2_open() fails, it raises a bus message, but without an
element, a precondition check fails on
gst_element_message_full_with_details() generating a crash if running
with fatal-warnings debug mode.
GstV4l2Error is a helper to raise error bus messages when it is
appropiated. This patch changes the direct bus messages to this
helper, and the elements will actually send the error message.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/694>
When using this mode each frame is split in two fields, each one being
transferred using its own buffer.
This is implemented with the V4L2_FIELD_ALTERNATE field format in v4l2.
This mode is enabled using a caps filter such as
"v4l2src ! video/x-raw\(format:Interlaced\)"
Here are the main changes related to this feature:
- use the INTERLACED caps feature with this mode.
- in this mode both fields of a given frame have the same sequence/offset
so adjust the algorithm checking for lost field/frame accordingly.
- double pool's min number of buffers as each frame requires 2 buffers.
Fix#504
Co-authored-by: Zeeshan Ali <zeenix@collabora.co.uk>
Use GST_VIDEO_INFO_FIELD_HEIGHT() instead of GST_VIDEO_INFO_HEIGHT()
when we actually want the field height rather than the frame height.
So far both are equals but that won't longer be the case when
implementing alternate interlace mode.
gst_v4l2_object_set_format_full() was returning FALSE without setting
an error. Caller code (gst_v4l2src_fixate()) was then derefing a
NULL pointer when trying to handle the error.
libv4l2 reset the colorpace to 0 and does not do any request to the
driver. This yields an invalid colorspace which currently cause a
negotiation failure. This workaround by ignoring bad values during the
TRY_FMT step.
We were already supporting horizontal padding by setting bytesperline to
the buffer stride but not vertical one.
We are now updating the format height with the padded height and crop to
the actual video resolution if needed.
The function gst_v4l2_object_add_interlace_mode() has repeating code so
it's best use a loop instead. That will make it easy and simple to add
additional interlace modes in a following patch.
If there was no interlace-mode field in the caps. Read back the value
selected by the driver. This way, if the driver does not support
progressive, then it will automatically negotiate the returned mode
unless this mode is not supported by GStreamer.
This method was already used for colorimetry. Just like colorimetry, the
interlace mode is not longer probed by v4l2src dues to performance
issues.
Fixes#511
This method will check if a buffer, base on it's video meta,
can be imported. It will also try and adapt the request stride
in case this is the only that miss-match.
https://bugzilla.gnome.org/show_bug.cgi?id=583890
The desired colorimetry is logged with all parameters (colorpsace,
range, matrix, and transfer function), but of the values actually
set by the driver, only colorspace is logged. Complete the debug
log message to display all colorimetry parameters:
Desired colorspace is 8:1:1:1
Got format of 640x480, format YU12, nb planes 1, colorspace 8
->
Desired colorspace is 8:1:1:1
Got format of 640x480, format YU12, nb planes 1, colorspace 8:0:0:0
https://bugzilla.gnome.org/show_bug.cgi?id=796940
