Change-Id: Ib016fc8f0066980e3e5122b3f286680adc228ff9
Signed-off-by: Jean-Marc Valin <jeanmarcv@google.com>

The exp2 function was approximated using lolremez, achieving an
accuracy of less than 2*10^-7 within the range of 0 to 1.

Signed-off-by: Jean-Marc Valin <jeanmarcv@google.com>

Change-Id: Ibd0d16918272cb568923d384475e139dc312c61b
Signed-off-by: Jean-Marc Valin <jeanmarcv@google.com>

The log2 function was approximated using lolremez, achieving an
accuracy of less than 1.4*10^-8 within the range of 1 to 2.

Signed-off-by: Jean-Marc Valin <jeanmarcv@google.com>

Convert to 16 bits only at the very end

Compensates for the spectral leakage and the fact that we don't have
an explicit masking curve.

Detecting tones can help us prevent the encoder from getting confused
by them.

Git will now remember it for us forever.

Signed-off-by: Jean-Marc Valin <jeanmarcv@google.com>

Even if it is followed by repeated short extensions with payloads.
We track the total size of the short extension payloads that need
 to be repeated, and remove that from the available space for the
 last long extension.
This means we can no longer use L=0 on a repeat to skip coding a
 frame separator when the extensions to be repeated contain a long
 extension followed by one or more short extensions with payloads
 (and there are no more non-repeated extensions in the current
 frame, but there are extensions in the next frame), but this case
 seems uncommon, and hard to explain.
The savings from always being able to skip coding a length when the
 final extensions are repeated extensions with at least one long
 extension is likely higher.
We can still skip a frame separator if we repeat only short
 extensions.

Also update existing tests and add a test for the case where we do
 not have enough space for the repeated short extensions after the
 last long extension.

Signed-off-by: Jean-Marc Valin <jeanmarcv@google.com>

This avoids the need to code a frame separator in the case that the
 last repeated extension is a short extension, and the next
 non-repeated extension is in the following frame instead of the
 current one (saving one additional byte).
Also add tests for both encoding and decoding this.

Signed-off-by: Jean-Marc Valin <jeanmarcv@google.com>

This gives more confidence that the generation code always produces
 output that the parsing code can parse.

Signed-off-by: Jean-Marc Valin <jeanmarcv@google.com>

Also adds tests which exercise generating repeated extensions as
 well as the count_ext() and parse_ext() API for parsing extensions
 in frame order.

Signed-off-by: Jean-Marc Valin <jeanmarcv@google.com>

Right now, opus_packet_extensions_parse() returns the extensions in
 the order they appear in the packet, which is no longer necessarily
 in frame order.
This adds a new (still private) API that returns parsed extensions
 in frame order, even when repeated extensions are used.
Nothing has been converted to use this new API yet.

Signed-off-by: Jean-Marc Valin <jeanmarcv@google.com>