This reverts commit 9f407afa.

Also added 3rd clause to "master" COPYING file

Thanks to Vincent Penquerc'h

Gregory Maxwell authored 13 years ago and Jean-Marc Valin committed 13 years ago

Also change the packet length in the API from int to opus_int32
because repacketized frames are able to go beyond 32767 bytes
in size.

Also using the same int->float conversion functions for SILK as for CELT
and changed encoder implementation default to constrained VBR just to
be safe when VBR gets more aggressive.

- When it cannot produce the rate it's being asked, the encoder now
  returns a "PLC packet"
- Makes it possible to use the CELT PLC for more than 20 ms

Koen Vos authored 13 years ago and Jean-Marc Valin committed 13 years ago

decoder:
- fixed incorrect scaling of filter states for the smallest quantization
  step sizes
- NLSF2A now limits the prediction gain of LPC filters

encoder:
- increased damping of LTP coefficients in LTP analysis
- increased white noise fraction in noise shaping LPC analysis
- introduced maximum total prediction gain.  Used by Burg's method to
  exit early if prediction gain is exceeded.  This improves packet
  loss robustness and numerical robustness in Burg's method
- Prefiltered signal is now in int32 Q10 domain, from int16 Q0
- Increased max number of iterations in CBR gain control loop from 5 to 6
- Removed useless code from LTP scaling control
- Optimization: smarter LPC loop unrolling
- Switched default win32 compile mode to be floating-point

resampler:
- made resampler have constant delay of 0.75 ms; removed delay
  compensation from silk code.
- removed obsolete table entries (~850 Bytes)
- increased downsampling filter order from 16 to 18/24/36 (depending on
  frequency ratio)
- reoptimized filter coefficients

These fix corner cases discovered during the latest fuzzing tests.

The CELT encoder could end up using a non-max bit-rate and not use
all the bytes it's supposed to use.

This avoids potential alignment issues with allocating a char
array on the stack.

Koen Vos authored 13 years ago and Jean-Marc Valin committed 13 years ago

Also some comment/warning fixes

Only encoder changes were necessary because this uses the same
"redundant frames" mechanism as SILK<->CELT switching.
This also fixes a regression introduced in 78291b27 that was
causing the encoder to go back and forth between bandwidths when
SILK wasn't ready to change.

This is achieved by running the encoding process in a loop and
padding when we don't reach the exact rate. It also implements
VBR-with-cap, which means we no longer need to artificially decrease
the SILK bandwidth when it's close to the cap.

Only one of the two required checks in the encoder were updated. Thanks to
Tim for tracking down the actual cause of the mismatch.

These were caused by not prefilling the hybrid CELT state

Koen Vos authored 13 years ago and Jean-Marc Valin committed 13 years ago

- fixes the test_opus "skip" for stereo
- fixes 6 visual studio compile warnings
- adds several header files to visual studio's include folder

Making sure not to abruptly "de-collapse" the stereo for such transitions

When SILK decided not to use the desired bandwidth, the redundancy
could be encoded at the desired bandwidth rather than at the actual
bandwidth used.