clang now (in the upcoming 5.0 version) is capable of building our
arm assembly without relying on gas-preprocessor, although clang/LLVM
doesn't support .dn register aliases.

The VC1 MC assembly was only built and used if the chosen assembler
supported the .dn directives though. This was supported as long as
gas-preprocessor was used.

This means that VC1 decoding got a speed regression on clang 5.0,
unless the user manually chose using gas-preprocessor again.

By avoiding using the .dn register aliases, we can build the VC1 MC
assembly with the latest clang version.

Support for the .dn/.qn directives in clang/LLVM isn't actively planned,
see https://bugs.llvm.org/show_bug.cgi?id=18199.

This partially reverts 896a5bff.
Signed-off-by: Martin Storsjö <martin@martin.st>

This is more correct.
Signed-off-by: Martin Storsjö <martin@martin.st>

Bug-Id: 1036
CC: libav-stable@libav.org

It doesn't depend on hevcdec anymore.
Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

Based on the H264 SEI implementation.

This will be mainly useful once support for SEI messages that can be
used by the hevc parser are implemented, like Picture Timing.
Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

When targeting windows, the .arch directive isn't available.

So far, when building for windows, we've always used gas-preprocessor,
both when using msvc's armasm and when using clang. Lately, clang/llvm
has implemented the last missing piece (altmacro support) for building
our assembly without gas-preprocessor. This means that we now build
for arm/windows with clang without any extra compatibility layer.
Signed-off-by: Martin Storsjö <martin@martin.st>

Signed-off-by: Martin Storsjö <martin@martin.st>

This doesn't change the actual behaviour of the code but improves
readability.
Signed-off-by: Martin Storsjö <martin@martin.st>

Aliased compressed AAC bytes are almost certainly not meaningful SBR
data. In the wild this causes harsh artifacts switching HE-AAC streams
that don't have SBR headers aligned with segment boundaries.

Turning off SBR falls back to a default set of upsampling parameters
that can function as a sort of error concealment. This is consistent
with how the decoder handles other sorts of errors.

Bug-Id: 1047
CC: libav-stable@libav.org
Signed-off-by: Sean McGovern <gseanmcg@gmail.com>

This makes the currently semi-public avpriv_aac_parse_header() function
private to libavcodec and adds a proper public API function to return
the parts of the ADTS header required in libavformat.

This makes the bitstream.h header leaner.
Signed-off-by: Diego Biurrun <diego@biurrun.de>

Do not rely on indirectly including it from bitstream.h.
Signed-off-by: Diego Biurrun <diego@biurrun.de>

Signed-off-by: Martin Storsjö <martin@martin.st>

This is something of a hack.  It allocates a new hwframe context for
the target format, then maps it back to the source link and overwrites
the input link hw_frames_ctx so that the previous filter will receive
the frames we want from ff_get_video_buffer().  It may fail if
the previous filter imposes any additional constraints on the frames
it wants to use as output.

Also refactor a little and improve error messages to make failure
cases easier to understand.

Use the flags argument of av_hwframe_ctx_create_derived() to pass the
mapping flags which will be used on allocation.  Also, set the format
and hardware context on the allocated frame automatically - the user
should not be required to do this themselves.

Factorises out existing surface initialisation code to reuse.

Some frames contexts are not usable without additional format-specific
state in hwctx.  This change adds new functions frames_derive_from and
frames_derive_to to initialise this state appropriately when deriving
a frames context which will require it to be set.

This only supports one device globally, but more can be used by
passing them with input streams in hw_frames_ctx or by deriving new
devices inside a filter graph with hwmap.

If -hwaccel foo is supplied without any other device options, and the
foo hwaccel is meant to have a device, try to make such a device with
default parameters for the hwaccel to use.

This was left over from an earlier version which created the new
packet inside the current frame structure.  Now it just leaks an
unused packet, so remove the allocation entirely.

The function currently accepts a PutBitContext and a GetBitContext,
which hardcodes their sizes into the lavc ABI. Since the function is
quite small and only called in a few places, the simplest solution is
making it inline, thus avoiding a runtime dependency completely.
Signed-off-by: Diego Biurrun <diego@biurrun.de>

Before:              Cortex     A7      A8      A9     A53
hevc_add_res_8x8_8_neon:     116.0    58.7    80.2    90.7
hevc_add_res_32x32_8_neon:  1230.0   737.5  1187.5   974.4
After:
hevc_add_res_8x8_8_neon:      97.7    57.0    73.7    80.0
hevc_add_res_32x32_8_neon:  1216.0   698.7  1127.5   827.1
Signed-off-by: Martin Storsjö <martin@martin.st>

Optimized by Alexandra Hájková.
Signed-off-by: Martin Storsjö <martin@martin.st>

request_channel_layout is a decoder option and it makes no sense
to have it in a parser.

This feature was needed in the past when the decoder was allowed
to reuse the avctx from the demuxer. Nowadays the decoder receives
only the parameters from it, already containing the real channel
layout (and the correct request_channel_layout option).

After initialization the decoder overwrites the channel layout
with the downmixed one that is actually output, so there is no need
to preserve this functionality in the parser.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

request_channel_layout is a decoder option and it makes no sense
to have it in a parser.

This feature was needed in the past when the decoder was allowed
to reuse the avctx from the demuxer. Nowadays the decoder receives
only the parameters from it, already containing the real channel
layout (and the correct request_channel_layout option).

After initialization the decoder overwrites the channel layout
with the downmixed one that is actually output, so there is no need
to preserve this functionality in the parser.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

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

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

Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

Uses the just-added ALLOW_PROFILE_MISMATCH flag.

The non-H.26[45] codecs already use this form.  Since we don't
currently generate I frames for codecs which support them separately
to IDR, the p_per_i variable is set to infinity by default so that it
doesn't interfere with any other calculation.  (All the code for I
frames still exists, and it works for H.264 if set manually.)

Purely cosmetic change, will make code more readable once the new
channel layout takes over.

The same warning is issued when actual unknown spherical metadata is
found further down in the function.
Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>

Inlining public functions hardcodes their implementation into the ABI,
so it should be avoided unless there is a very good reason for it. No
such reason exists in this case.