Allow extensibility.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Implement av_buffersink_read() and av_buffersink_read_samples()
for ffmpeg's version of buffersink.

With this change, avconv linked against ffmpeg's libraries passes
the same number of tests whether it uses ffbuffersink or
buffersink_old.

They are part of the public API. Their libav compatibility
counterpart are already enabled unconditionally.

Parse expression only when a new value is explicitly specified.

In particular, avoid double free in case an old expression value is
cached, it is set in the context, it is freed as the old value, and
finally the pointer stored in the context is freed again when the filter
is released.

Fix programmatic selection of accepted pixel formats.

Signed-off-by: Stefano Sabatini <stefasab@gmail.com>

Fixes ticket1752

Commit message by commiter
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Possibly safer.

Previously when saturation was reinited, the old value was freed when
setting options, and freed again in PARSE_EXPRESSION().

Fixes regression since 98f753ec51

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Compute duration in microseconds, rather than in timebase units. Decrease
approximation errors.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This avoid a crash when the filter fails before config_input(),
typically with a syntax error in the next filter:
    select=gt(scene\,.4),select=fail

The warning is:
libavfilter/avfiltergraph.c: In function ‘avfilter_graph_config’:
libavfilter/avfiltergraph.c:528:9: warning: ‘best_idx’ may be used uninitialized in this function [-Wuninitialized]
libavfilter/avfiltergraph.c:479:13: note: ‘best_idx’ was declared here

Initialize it to an invalid value and add an assert that it's properly
set later.

Signed-off-by: Mans Rullgard <mans@mansr.com>

Some implementations of sscanf do not handle a space before a trailing %n
properly.

As an example, MSVC's does this for the second insatnce in this patch, for
an input of "0x3:c0=c1:c1=c0":
    1) Match the final "c0" or "c1".
    2) Realize it's at the end of the string.
    3) Check for %n.
    4) There is no %n, but a space instead.
    5) Leave 'len' unitilialized.

So, move it out of the sscanf format strings, and call skip_spaces instead.

This bug does not affect skip_spaces since %n is the first and only formatting
string.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

Signed-off-by: Stefano Sabatini <stefasab@gmail.com>

The aresample filter changes the format, layout and/or sample rate,
it can not copy them blindly from its input.

Related to trac ticket #1671.

This fixes two problems:
 - the invalid pad.name stack pointer after init() ends
 - the duplicated name for all inputs

Should be more robust/consistent.

Useful for dealing with constant frame-rate video.

Fix warning when compiling boxblur.

While this is technically a major API break, practically there will be no
one using that function since the filtering API is mostly private, so
that function alone is not usable.

There is no MMX code anyway.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

It already uses av_strcasecmp.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This avoid recalculating it and in case w/h changed avoids crashes.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Fixes an infinite loop on flush when avresample_get_delay() still
reports some samples but avresample_convert() doesn't return any data.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Any volunteers to port the pp and spp filters from libmpcodec?

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

The native filter transpose is perfectly equivalent.

Increase performance (slightly).

If not set to NULL, the reference is freed by ff_end_frame(), and later
accessed in end_frame() by the filter code, causing a crash.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>