Fixes a reported (but false) race condition in tsan for fate-apng:

WARNING: ThreadSanitizer: data race (pid=6274)
  Read of size 4 at 0x7d680001ec78 by main thread (mutexes: write M1338):
    #0 update_thread_context src/libavcodec/pngdec.c:1456 (ffmpeg+0x000000dacf0c)
[..]
  Previous write of size 4 at 0x7d680001ec78 by thread T1 (mutexes: write M1335):
    #0 decode_idat_chunk src/libavcodec/pngdec.c:737 (ffmpeg+0x000000dae951)

Values from subsequent values are guaranteed to be identical (since
poc and nal_unit_type are checked to be the same between slices), so
this doesn't affect output in any way, but does resolve the remaining
reported race conditions (by tsan) in fate-hevc.

In practice, this fixes tsan warnings like this:

WARNING: ThreadSanitizer: data race (pid=25334)
  Read of size 4 at 0x7d9c0001adcc by main thread (mutexes: write M1386):
    #0 hevc_update_thread_context src/libavcodec/hevcdec.c:3310 (ffmpeg+0x000000b41c7c)
[..]
  Previous write of size 4 at 0x7d9c0001adcc by thread T1 (mutexes: write M1383):
    #0 hls_slice_header src/libavcodec/hevcdec.c:596 (ffmpeg+0x000000b43a22)

Otherwise the thread may still be in the middle of decoding a previous
frame, which would effectively trigger a race condition on any field
concurrently read and written.

In practice, this fixes tsan warnings like the following:

WARNING: ThreadSanitizer: data race (pid=17380)
  Write of size 4 at 0x7d64000160fc by main thread:
    #0 update_context_from_user src/libavcodec/pthread_frame.c:335 (ffmpeg+0x000000dca515)
[..]
  Previous read of size 4 at 0x7d64000160fc by thread T2 (mutexes: write M1821):
    #0 ff_thread_report_progress src/libavcodec/pthread_frame.c:565 (ffmpeg+0x000000dcb08a)

Should fix tsan warnings in fate-fifo-muxer-h264/wav:

WARNING: ThreadSanitizer: data race (pid=26552)
  Write of size 4 at 0x000001e0d7c0 by main thread:
    #0 transcode_init src/ffmpeg.c:3761 (ffmpeg+0x00000050ca1c)
[..]
  Previous read of size 4 at 0x000001e0d7c0 by thread T1:
    #0 decode_interrupt_cb src/ffmpeg.c:460 (ffmpeg+0x0000004fde19)

Fixes tsan warnings in several audio codecs (flac, alac, wavpack, tta
and tak) that look like this:

WARNING: ThreadSanitizer: data race (pid=14340)
  Read of size 4 at 0x7d64000169d8 by main thread (mutexes: write M1335):
    #0 update_context_from_thread src/libavcodec/pthread_frame.c:284 (ffmpeg+0x000000dc795f)
[..]
  Previous write of size 4 at 0x7d64000169d8 by thread T1 (mutexes: write M1333):
    #0 wavpack_decode_block src/libavcodec/wavpack.c:1012 (ffmpeg+0x00000112b175)

This is how the ref list manager links bitstream IDs to H264Picture/Ref
objects, and is local to the producer thread. There is no need for the
consumer thread to know the bitstream IDs of its references in their
respective producer threads.

In practice, this fixes tsan warnings when running fate-h264:

WARNING: ThreadSanitizer: data race (pid=19295)
  Read of size 4 at 0x7dbc0000e614 by main thread (mutexes: write M1914):
    #0 ff_h264_ref_picture src/libavcodec/h264_picture.c:112 (ffmpeg+0x0000013b3709)
[..]
  Previous write of size 4 at 0x7dbc0000e614 by thread T2 (mutexes: write M1917):
    #0 build_def_list src/libavcodec/h264_refs.c:91 (ffmpeg+0x0000013b46cf)

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

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

now gop_size <= (max_b_frames + 1) * p_per_i + 1 (IDR frame),
so celing p_per_i = (gop_size - 1 + max_b_frames) / (max_b_frames + 1)
Signed-off-by: Jun Zhao <jun.zhao@intel.com>
Signed-off-by: Leilei <leilei.shang@intel.com>
Signed-off-by: Mark Thompson <sw@jkqxz.net>

This was merged in the wrong place.

Cherry-picked from libav commit cfee5e1aSigned-off-by: James Almer <jamrial@gmail.com>

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

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

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

Fixes: undefined behavior
Fixes: 702974
Found-by: Thomas Guilbert <tguilbert@google.com>
Reviewed-by: Rostislav Pehlivanov <atomnuker@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

This avoids an integer overflow
the solution matches oggparsevorbis.c and 45581ed1

Fixes: 700242
Found-by: Thomas Guilbert <tguilbert@google.com>
Reviewed-by: Rostislav Pehlivanov <atomnuker@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Makes the test output consistent across all targets.

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

* commit 'e18ba2df':
  hwcontext_dxva2: make sure the sw frame format is the right one during transfer
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

* commit '5a1d605c':
  hwcontext_dxva2: split transfer_data() into upload/download functions
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

* commit '9d702657':
  hwcontext_dxva2: fix handling of the mapping flags
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

* commit '0d3176e3':
  hwcontext_dxva2: do not assume the destination format during mapping is always the right one
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>

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

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

* commit 'adb0e941':
  avpacket: Mark src pointer as constant

See 5bb3f882Merged-by: Clément Bœsch <u@pkh.me>

* commit '0a4b9d0c':
  hlsenc: Add encryption support

This commit is a noop, see 907ac20a

Note that this commit differs from our encryption support in various
ways so it may need some adjustments in the future.
Merged-by: Clément Bœsch <u@pkh.me>

Commits ade370a4 and e3fb74f7 were reordered while merging, so this
change got lost.

* commit 'd860a3cc':
  crypto: Add encryption support

See 00d4013dMerged-by: Clément Bœsch <u@pkh.me>

* commit '76167140':
  qsvdec: Drop stray extra braces around initializer
Merged-by: Clément Bœsch <u@pkh.me>

* commit '715b8243':
  qsv: Drop some unused variables
Merged-by: Clément Bœsch <u@pkh.me>

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

* commit 'bb265b76':
  examples/transcode_aac: Drop pointless return value const qualifier

This commit is a noop, the function doesn't exist in FFmpeg anymore
since e181e290.
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'bfe92dfe':
  Ignore all generated example binaries

This commit is a noop, the .gitignore was updated during the merges of
these examples.
Merged-by: Clément Bœsch <u@pkh.me>

* commit 'bf864627':
  doc: Add note about recent regression in AviSynth+
Merged-by: Clément Bœsch <u@pkh.me>

* commit '3cc3463f':
  avisynth: Support pix_fmts added to AviSynth+

This commit is mostly a noop, see
92916e85.

Cosmetics and a small fix are merged.
Merged-by: Clément Bœsch <u@pkh.me>