In this case switching to .formats.samples even allows to avoid
the runtime check for which filter is currently used.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
If one looks at the many query_formats callbacks in existence,
one will immediately recognize that there is one type of default
callback for video and a slightly different default callback for
audio: It is "return ff_set_common_formats_from_list(ctx, pix_fmts);"
for video with a filter-specific pix_fmts list. For audio, it is
the same with a filter-specific sample_fmts list together with
ff_set_common_all_samplerates() and ff_set_common_all_channel_counts().
This commit allows to remove the boilerplate query_formats callbacks
by replacing said callback with a union consisting the old callback
and pointers for pixel and sample format arrays. For the not uncommon
case in which these lists only contain a single entry (besides the
sentinel) enum AVPixelFormat and enum AVSampleFormat fields are also
added to the union to store them directly in the AVFilter,
thereby avoiding a relocation.
The state of said union will be contained in a new, dedicated AVFilter
field (the nb_inputs and nb_outputs fields have been shrunk to uint8_t
in order to create a hole for this new field; this is no problem, as
the maximum of all the nb_inputs is four; for nb_outputs it is only
two).
The state's default value coincides with the earlier default of
query_formats being unset, namely that the filter accepts all formats
(and also sample rates and channel counts/layouts for audio)
provided that these properties agree coincide for all inputs and
outputs.
By using different union members for audio and video filters
the type-unsafety of using the same functions for audio and video
lists will furthermore be more confined to formats.c than before.
When the new fields are used, they will also avoid allocations:
Currently something nearly equivalent to ff_default_query_formats()
is called after every successful call to a query_formats callback;
yet in the common case that the newly allocated AVFilterFormats
are not used at all (namely if there are no free links) these newly
allocated AVFilterFormats are freed again without ever being used.
Filters no longer using the callback will not exhibit this any more.
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Most instances ff_add_formats() actually only ever add one format;
this function can be used to simplify those callers.
Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
A filter's formats.query callback is only called after all
the inputs and outputs have already been created.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The current code used a pointer to an array (of arrays) that
is offset relative to the start of the actually allocated buffer.
Yet offsetting the pointer is only done on success, whereas the
freeing code believes it to have happened even on error.
So if any of the subarrays (or the subarrays' subarrays) can't
be successfully allocated, one gets a bad free in free_lut().
Furthermore, said offsetting is only permissible in case the
offsetted pointer points in the allocated buffer (here: in case
the LUT's min_r is <= 0), as pointer arithmetic is undefined
in case it exceeds the allocated object.
Moreover, in case one of the subarrays couldn't be allocated,
the code nevertheless tried to free the subarray's subarrays;
and in case one of the subarray's subarrays could not be allocated
successfully, there will be an invalid free, too, because the
pointers for the subarrays' subarrays are also offset compared
to the base pointer.
This commit fixes all of this, by using the actually allocated
pointer for freeing and by adding appropriate checks before
freeing the subarrays. The former also allows to distinguish
the cases in which the lut is currently only half-allocated due to
an error in an earlier allocation attempt from the success case.
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Andreas Rheinhardt
Paul B Mahol