av_gcd is now always defined regardless of input. This documents this
change in the "documented API". Two benefits (closely related):
1. The function is robust, and there is no need to worry about INT64_MIN, etc.

2. Clients of av_gcd, like av_reduce, can now be made fully correct. Currently,
av_reduce can trigger undefined behavior if e.g num is INT64_MIN due to
integer overflow in the FFABS. Furthermore, this undefined behavior is
completely undocumented, and could be a fuzzer's paradise. The FFABS was needed in the past as
av_gcd was undefined for negative inputs. In order to make av_reduce
robust, it is essential to guarantee that av_gcd works for all int64_t.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

Fix a segfault when no encoder is found for a default codec
with a complex filter graph.

Signed-off-by: Steven Robertson <steven@strobe.cc>
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Fixes regression with iJi.ogv
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

QT ignores the value written in the frame header.
Issue reported by forum user Koracas.

This ensures that no undefined behavior is invoked, while retaining
identical return values in all cases and at no loss of performance
(identical asm on clang and gcc).
Essentially, this patch exchanges undefined behavior with implementation
defined behavior, a strict improvement.

Rationale:
1. The ideal solution is to have the return type a uint64_t. This
unfortunately requires an API change.
2. The only pathological behavior happens if both arguments are
INT64_MIN, to the best of my knowledge. In such a case, the
implementation defined behavior is invoked in the sense that UINT64_MAX
is interpreted as INT64_MIN, which any reasonable implementation will
do. In any case, any usage where both arguments are INT64_MIN is a
fuzzer anyway.
3. Alternatives of checking, etc require branching and lose performance
for no concrete gain - no client cares about av_gcd's actual value when
both args are INT64_MIN. Even if it did, on sane platforms (e.g all the
ones FFmpeg cares about), it produces a correct gcd, namely INT64_MIN.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

This is likely more precise and conveys the intent better.
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

This is more concise and conveys the intent better.
Furthermore, it is likely more precise as well due to lack of floating
point division.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

This is likely more precise and conveys the intent better.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

This is likely more precise and conveys the intent better.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

This is likely more precise and conveys the intent better.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

It is an internal swscale function and thus should not be exported.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>

It is an internal swscale symbol and thus should not be exported.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>

They are not in public headers and not used outside of libavformat.
Reviewed-by: Hendrik Leppkes <h.leppkes@gmail.com>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>

This is likely more precise and conveys the intent better.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

This is likely more precise and conveys the intent better.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

This is likely more precise and conveys the intent better.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

This is likely more precise and conveys the intent better.
The expression has also been accordingly simplified.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Signed-off-by: Paul B Mahol <onemda@gmail.com>

Signed-off-by: Kyle Swanson <k@ylo.ph>
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Kyle Swanson <k@ylo.ph>
Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

* commit '8edaf625':
  libopenh264enc: Count and warn about the number of skipped frames
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

* commit '9e14a992':
  libopenh264enc: Add an option for controlling the frame skipping
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

* commit 'b8deb7c3':
  opus: Do not call vector_fmul_scalar on zero samples
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

* commit '6dcd8229':
  opus: Buffer the samples from the correct offset
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

* commit 'f3aff31e':
  avpicture: Deprecate the single fields
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

* commit 'cd0e0881':
  avconv: support infinite loop for the loop option
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

* commit 'a9a60106':
  avpacket: Provide an alloc and a free function for the struct
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

* commit '9b56d5c1':
  avpacket: Deprecate av_dup_packet
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

* commit 'd584533c':
  avformat: Rework add_to_pktbuf
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

For the 10-show-existing-frame, the source file indeed has a timestamp
of 3 (or 100/33) for the second visible frame, so the fix appears to
work correctly. For the other, only the timebase is fixed, but again
appears to be correct now.

Signed-off-by: James Almer <jamrial@gmail.com>