Several cbs-functions had an unused CodedBitstreamContext parameter.
This commit removes these.
Reviewed-by: Mark Thompson <sw@jkqxz.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
When testing whether a particular unit should be kept or discarded, it
is best to start at the very last unit of a fragment and count down,
because that way a unit that will eventually be deleted won't be
memmoved during earlier deletions; and frag/au->nb_units need only be
evaluated once in this case and the counter is automatically correct
when a unit got deleted.
It also works for double loops, i.e. when looping over all SEI messages
in all SEI units of an access unit.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
This commit changes filter_units to (a) use ff_bsf_get_packet_ref
instead of ff_bsf_get_packet (thereby avoiding one malloc and free per
filtered packet) and (b) to use only one packet structure at all,
thereby avoiding a call to av_packet_copy_props (or, in case of
passthrough, to av_packet_move_ref).
(b) has been made possible by the recent changes to ff_cbs_write_packet.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
According to the BSF API, when a BSF is finished with an input packet,
it should return AVERROR(EAGAIN) to signal that another packet should be
sent to the BSF via av_bsf_send_packet that the actual BSF can receive
via ff_bsf_get_packet[_ref]. filter_units on the other hand simply called
ff_bsf_get_packet again if the first packet received didn't result in
any output. This call of course returned AVERROR(EAGAIN) which was
returned, but it is nevertheless better to not include a fake loop.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
According to the API, the packet structure a bsf receives must not be
touched on failure, yet filter_units nevertheless did it.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Currently, a fragment's unit array is constantly reallocated during
splitting of a packet. This commit changes this: One can keep the units
array by distinguishing between the number of allocated and the number
of valid units in the units array.
The more units a packet is split into, the bigger the benefit.
So MPEG-2 benefits the most; for a video coming from an NTSC-DVD
(usually 32 units per frame) the average cost of cbs_insert_unit (for a
single unit) went down from 6717 decicycles to 450 decicycles (based
upon 10 runs with 4194304 runs each); if each packet consists of only
one unit, it went down from 2425 to 448; for a H.264 video where most
packets contain nine units, it went from 4431 to 450.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@googlemail.com>
This is in preparation for another patch that will stop needless
reallocations of the unit array.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@googlemail.com>
This can remove units with types in or not in a given set from a stream.
For example, it can be used to remove all non-VCL NAL units from an H.264 or
H.265 stream.
