If building a static library, marking symbols as dllexport causes them
to be exported from the final executable. For example, run
objdump -x opus_demo.exe on a --disabled-shared build and look for the
export table; there should not be one in a normal Win32 .exe file, but
when linking static libopus, the exe exports all of the opus_* public
functions.

Use the libtool-defined DLL_EXPORT flag to determine whether we are
building a DLL and only specify __declspec(dllexport) in that case.

Ralph Giles authored 9 years ago and Ralph Giles committed 9 years ago

This is a reasonable choice for the (non-linear) dynamic
range of mu-law. A-law is technically 13 bit, maybe 12;
experimentation is needed.

Per irc discussion with Jean-Marc, Ron, and Mark Harris.

Mark Harris authored 9 years ago and Jean-Marc Valin committed 9 years ago

Signed-off-by: Jean-Marc Valin <jmvalin@jmvalin.ca>

We use at most 16 when using fixed-point (for the API or the
 internal implementation), but we didn't tell anyone this.

This way we won't break this by accident.

Limit now at 2*streams-1 and anything below that returns OPUS_BUFFER_TOO_SMALL
rather than OPUS_BAD_ARG

Bruno Randolf authored 11 years ago and Jean-Marc Valin committed 11 years ago

Signed-off-by: Jean-Marc Valin <jmvalin@jmvalin.ca>

Works by turning off pitch and energy prediction in CELT, while
setting first_frame_after_reset in SILK to disable pitch and LSF interpolation
and reduce LPC gain.

Newer versions of MSVC are unhappy with the strategy of the build
 environment redefining "inline" (even though they don't support the
 actual keyword). Instead we define OPUS_INLINE to the right thing
 in opus_defines.h.

This is the same approach we use for restrict.

Also makes the CTL bad argument handling more consistent to avoid mistakes
 like that in the future.  Also updates the variable duration docs.

Jacek Caban authored 11 years ago and Gregory Maxwell committed 11 years ago

Signed-off-by: Gregory Maxwell <greg@xiph.org>

The idea is that the rate of each stream is adjusted based on its
contribution to the total energy of a stereo downmix.

Variable duration option renamed to OPUS_SET_EXPERT_FRAME_DURATION,
with new API.
Also moves up the analysis to avoid having to do int->float conversion
on large buffers.

The search is based on minimizing the bitrate increase due to transients
by considering we can reduce the "transient boost" by reducing the frame
size, at the cost of increasing the normal overhead.

OPUS_EXPORT was conditionalized on OPUS_BUILD, so that symbols
are export based on public header declarations when building
opus as a library, but not when those headers are included in
other programmes. This doesn't address the case when the opus
source and its caller are both included in the same monolithic
build.

In that case we want to define OPUS_BUILD, to indicate that we
are compiling the codec source, but not export the symbols. To
support this, only define OPUS_EXPORT if it is not already defined.
This allows build scripts to -DOPUS_EXPORT and override the
platform-specific attribute decortation in opus_defines.h.

Based on a patch by Sergey Ulanov.
http://git.chromium.org/gitweb/?p=chromium/deps/opus.git;a=commitdiff;h=6304b9628cb7244e3cc78f740aeb6659562f1857

Timothy B. Terriberry authored 12 years ago and Jean-Marc Valin committed 12 years ago

This avoids allocating any buffers on the stack that depend on the
 total channel count.
Such buffers could easily exceed the size of the
 NONTHREADSAFE_PSEUDOSTACK.
It also checks the frame_size argument in both the encoder and
 decoder to avoid allocating large stack buffers for opus_encode()
 calls that would fail anyway or opus_decode() calls that would
 never use all that space anyway.

In particular we no longer document the default complexity because
we're not guaranteeing to keep the default value constant.  In the
future the default may be lowered in order to keep the default
speed constant.

In addition to general reformatting and cleanup, this fixes a
 couple of important mistakes:
- The arguments to OPUS_SET_FORCE_CHANNELS are now 1 and 2, not 0
   and 1 (as they were when this was called OPUS_SET_FORCE_MONO).
- The default encoder mode is now constrained VBR, not unconstrained
   VBR.
It also documents defaults for all the other parameters.

Jean-Marc Valin authored 12 years ago and Gregory Maxwell committed 12 years ago

This implements an API used in future encoders to avoid dynalloc doing silly things
on periodic LSB patterns and to reduce the bitrate on near-silence.

We had previously advised people to -Drestrict on
non-C99 compilers, but this creates problems for
some of the MSVC headers. Instead this just
uses a macro and defines it sanely.

This is used to avoid dynalloc doing silly things on periodic LSB
patterns and to reduce the bitrate on near-silence.

This is the less-surprising behavior and will hopefully
result in fewer corner case bugs (e.g. losing gain
after seeking). This commit also updates the documentation.

This CTL was requested by Nicolas George for FFmpeg.

Gregory Maxwell authored 12 years ago and Jean-Marc Valin committed 12 years ago

In places where an ignored return or a null-arg is a sure indication
of a bug add the GCC warning attributes. The null arg annotation
is not enable for Opus itself because it will cause the compiler
to optimize out some null checks. I don't trust our callers
quite that much.

This was a problem for static builds

This reverts commit 9f407afa.

Also added 3rd clause to "master" COPYING file

See http://www.ietf.org/mail-archive/web/codec/current/msg02833.html
Still more changes to come

Doxygen is smart enough to insert a period if the paragraph
before the @see directive, which starts a new section, doesn't
have one. Unfortunately it's not smart enough to convert a
comma to a period. So while the "description, @see foo" idiom
used for the CTL documentation scans well in the header file,
the Doxygen output end up with "description,.\n".

Minimal change to remove the offending commas.

Ralph Giles authored 13 years ago and Jean-Marc Valin committed 13 years ago

We use macros to encapsulate the appropriate type and size
information for the different CTL requests, but the macros
still need to be used with the _ctl() function call and an
encoder or decoder instance structure. As such, just listing
the macro defines is confusing. Adding some examples outside
the OpusEncoder overview page should help with this.

Also document that OPUS_SET_APPLICATION can take
OPUS_APPLICATION_RESTRICTED_LOWDELAY.

Let's put it back in if/when we have a clearer view of voice/music detection