(cherry picked from commit 3d197514)

(cherry picked from commit 8848ba0b)

(cherry picked from commit 4936a48b)

In order to work correctly with the i965 driver, this also fixes the
direction of forward/backward references - forward references are
intended to be those from the past to the current frame, not from the
current frame to the future.

(cherry picked from commit 9aa251c9)

(cherry picked from commit 303fadf5)

(cherry picked from commit aa6b2e08)

(cherry picked from commit 62a1ef9f)

Not yet enabled for any hwaccels.

(cherry picked from commit d2e6dd32)
(cherry picked from commit 9203aac2)

Adds functions to convert to/from strings and a function to iterate
over all supported device types.  Also adds a new invalid type
AV_HWDEVICE_TYPE_NONE, which acts as a sentinel value.

(cherry picked from commit b7487f4f)

Creates a new device context from another of a different type which
refers to the same underlying hardware.

(cherry picked from commit b266ad56)

Previously this was leaking, though it actually hit an assert making
sure that the buffer had already been cleared when freeing the picture.

(cherry picked from commit 17aeee58)

The driver is somewhat bitrotten (not updated for years) but is still
usable for decoding with this change.  To support it, this adds a new
driver quirk to indicate no support at all for surface attributes.

Based on a patch by wm4 <nfxjfg@googlemail.com>.

(cherry picked from commit e791b915)

Fixes trac issue 6459.

Fixes CIDs 1403234 and 1403235

Fixes CID 1396267

Fixes CID 1396837

Fixes CIDs 1396414 and 1396415

Fixes CID 1396855

Fixes regression introduced by 5d0b8b1a.

Fixes: runtime error: signed integer overflow: 2147483584 + 128 cannot be represented in type 'int'
Fixes: 2164/clusterfuzz-testcase-minimized-4715936172998656

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

Fixes: runtime error: shift exponent -10 is negative

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

Fixes: 1775/clusterfuzz-testcase-minimized-5330288148217856

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

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

820 cpu cycles -> 660 cpu cycles for 100 put_bits32()
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

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

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

Signed-off-by: Ilia Valiakhmetov <zakne0ne@gmail.com>
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>

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

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

Simplifies writing assembly code that depends on available instructions.

LZCNT implies SSE2
BMI1 implies AVX+LZCNT
AVX2 implies BMI2

Fixes assertion failure
Fixes: 2112/clusterfuzz-testcase-minimized-4526878557732864

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

This avoids scaning beyond what a valid packet can contain
Fixes: Timeout
Fixes: 541/clusterfuzz-testcase-610189291657625

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

Fixes: 2208/clusterfuzz-testcase-minimized-5976593765761024

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

avcodec/wavpack: Fix runtime error: signed integer overflow: 1886191616 + 277872640 cannot be represented in type 'int'

Fixes: 2181/clusterfuzz-testcase-minimized-6314784322486272

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

As defined in "VP Codec ISO Media File Format Binding v1.0"
https://github.com/webmproject/vp9-dash/blob/master/VPCodecISOMediaFileFormatBinding.mdSigned-off-by: James Almer <jamrial@gmail.com>

Fixes: 2197/clusterfuzz-testcase-minimized-6010716676947968

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

Fixes: 2195/clusterfuzz-testcase-minimized-4736721533009920

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpegSigned-off-by: Michael Niedermayer <michael@niedermayer.cc>

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