sccparse holds last timecode in order to ignore invalid timecode
and fallback to the previous timecode. That should happen
when sccparse is handling seek event too. Otherwise single invalid
timecode before the target seek position will cause flow error.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1485>
GTK 4.14 comes with a new GL renderer that does not support GL shader
nodes anymore, so the conversion from non-premultiplied alpha to
premultiplied alpha has to happen differently.
For GTK 4.14 or newer we use the correct format directly when building the
texture, but only if a GLES3+ context is used. In that case the NGL renderer is
used by GTK, which supports non-premultiplied formats correctly and fast.
For GTK 4.10-4.12, or 4.14 and newer if a GLES2 context is used, we use a
self-mask to pre-multiply the alpha.
For GTK before 4.10, we use a GL shader and hope that it works.
Fixes https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/issues/488
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1452>
GTK expects GL textures to have premultiplied alpha. The ones we get
from GStreamer don't, leading to incorrect rendering of semitransparent
frames.
GTK 4.12 gained an API to set a different GL texture format, but it
won't help for older GTK versions. Plus, at the time of writing, it
causes a very slow download/upload path in GTK.
So, use a GTK GL shader node to premultiply the alpha without leaving
the GPU.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1312>
Allows any samplerate and make it negotiable. Fixing a scenario
where transcriberbin is configured with passthrough enabled,
(and negotiated samplerate is not supported by transcriber)
and then setting passthrough=false later during playback.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1287>
In certain cases, roundedcorners would negotiate to I420 even when user
supplied a non-zero border radius.
For example, the below pipeline leads to I420 being negotiated even
though a non-zero border radius was given. Ideally, this pipeline
should have failed at the negotiation stage.
```bash
gst-launch-1.0 -v \
videotestsrc num-buffers=1000 pattern=white ! \
video/x-raw,width=320,height=180 ! \
roundedcorners border-radius-px=10 ! videobox border-alpha=0 top=-10 left=-10 right=-10 bottom=-10 fill=yellow ! \
compositor name=comp sink_0::xpos=960 sink_0::ypos=0 sink_0::width=320 sink_0::height=180 sink_0::alpha=1.0 sink_1::xpos=960 sink_1::ypos=180 sink_1::width=320 sink_1::height=180 sink_1::alpha=1.0 \
sink_2::xpos=960 sink_2::ypos=360 sink_2::width=320 sink_2::height=180 sink_2::alpha=1.0 sink_3::xpos=0 sink_3::ypos=0 sink_3::width=960 sink_3::height=720 sink_3::alpha=1.0 ! \
video/x-raw,width=1280,height=720! x264enc ! mp4mux ! filesink location=test.mp4 \
videotestsrc num-buffers=1000 pattern=red ! \
video/x-raw,width=320,height=180 ! roundedcorners border-radius-px=10 ! comp. \
videotestsrc num-buffers=1000 pattern=blue ! \
video/x-raw,width=320,height=180 ! roundedcorners border-radius-px=10 ! comp. \
videotestsrc num-buffers=1000 pattern=green ! \
video/x-raw,width=960,height=720 ! roundedcorners border-radius-px=10 ! comp.
```
If border radius is non-zero, we should not really allow negotiation
to select I420. Fix this by returning only A420 for border-radius > 0
in `transform_caps` instead of returning both like earlier.
Another example of a simpler pipeline like below which would earlier work
```bash
gst-launch-1.0 videotestsrc pattern=red ! videoconvert ! video/x-raw,width=1923,height=1087,format=I420 ! roundedcorners border-radius-px=40 ! video/x-raw,format=I420 ! videoconvert ! gtksink
```
now fails with
```bash
WARNING: erroneous pipeline: could not link roundedcorners0 to videoconvert1, roundedcorners0 can't handle caps video/x-raw, format=(string)I420
```
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1211>
