Both gst_value_intersect and gst_value_subtract will call
gst_value_compare if one of their arguments isn't a list.
gst_value_compare will then re-do a check to see if one of
the arguments is a list (for the special case of comparing a unitary
value with a list of length 1).
The problem is that the various G_VALUE_HOLDS represent an expensive
amount of calling gst_value_compare (almost half of it) to see if
the provided arguments are list. These checks can be done without
when we know that the arguments aren't lists.
* Create a new "nolist" gst_value_compare which avoids that special
case comparision
Benchmarks:
valgrind/callgrind: average speedup in instruction calls for
gst_value_intersect and gst_value_subtract is around 56% (Makes 63%
of the calls it used to take previously)
tests/benchmarks/capsnego: With default settings (depth 4, children 3
607 elements), time taken for transition from READY to PAUSED:
Before : 00.391519153
After : 00.220397492
56% of the time previously used, +77% speedup
https://bugzilla.gnome.org/show_bug.cgi?id=731756
Currently the scan uses Boyer-moore method and its performance is good.
but, it can be optimized from an implementation of view.
The original scan code is implemented by byte array and index-based access.
In _scan_for_start_code(), the index is increasing from start to end and the
base address of the byte array is referred to as return value.
In the case, index-based access can be replaced by pointer access, which
improve the performance by removing index-related operations.
Its performace is enhanced by approximately 8% on arm-based embedded devices.
Although it seems trivial, it can affect the overall performance because the
_scan_for_start_code() function is very often called when H.264/H.265 video is
played.
In addition, the technique can apply for all architectures and it is good in
view of readability and maintainability.
https://bugzilla.gnome.org/show_bug.cgi?id=731442
The start and stop should represent the currently downloading region.
The estimated-total should represent the remaining time to download
the currently downloading region. This makes it a lot more useful
for applications because they can then use those values to update
the fill region and use the estimated time to delay playback.
Update the docs with this clarification.
First handle all miniobjects before we attempt to dereference the first
field pointer and look at the GType. With the recent glib change to
speed up G_IS_OBJECT, this causes crashes on miniobjects otherwise.
When a pad is added the need-parent flag is set to true, so when
they are removed the flag should be set back to false
This was preventing GstPads to be reused in elements (removed and
later re-added). A unit tests was added to verify that this is
working now.
The use case is tsdemux that has a program-number property and
allows the user to switch programs. In order to do that tsdemux
will remove the pads of the current program and add from the new
ones. The removed pads are kept in the demuxer for later if the
user selects the old program again.
