Timothy B. Terriberry authored 14 years ago and Jean-Marc Valin committed 14 years ago

These were used because the entropy coder originally came from
 outside libcelt, and thus did not have a common type system.
It's now undergone enough modification that it's not ever likely to
 be used as-is in another codec without some porting effort, so
 there's no real reason to maintain the typedefs separately.
Hopefully we'll replace these all again somedate with a common set
 of Opus typedefs, but for now this will do.

This fixes an issue caused by commit 6c8acbf1, which moved the
 ec_ilog() prototype from entcode.h to ecintrin.h, where the
 ec_uint32 typedef was not yet available.
Thanks to John Ridges for the report.

Got authorization from all copyright holders

Timothy B. Terriberry authored 14 years ago and Jean-Marc Valin committed 14 years ago

This fixes a number of issues for platforms with a 16-bit int, but
 by no means all of them.
The type change for ec_window (for platforms where sizeof(size_t)==2)
 will break ABI (but not API) compatibility with libsilk and libopus,
 and reduce speed on x86-64, but allows the code to work in real-mode
 DOS without using the huge memory model, which is useful for testing
 16-bit int compliance.

Timothy B. Terriberry authored 14 years ago and Jean-Marc Valin committed 14 years ago

This unifies the byte buffer, encoder, and decoder into a single
 struct.
The common encoder and decoder functions (such as ec_tell()) can
 operate on either one, simplifying code which uses both.
The precision argument to ec_tell() has been removed.
It now comes in two precisions:
  ec_tell() gives 1 bit precision in two operations, and
  ec_tell_frac() gives 1/8th bit precision in... somewhat more.
ec_{enc|dec}_bit_prob() were removed (they are no longer needed).
Some of the byte buffer access functions were made static and
 removed from the cross-module API.
All of the code in rangeenc.c and rangedec.c was merged into
 entenc.c and entdec.c, respectively, as we are no longer
 considering alternative backends.
rangeenc.c and rangede.c have been removed entirely.

This passes make check, after disabling the modes that we removed
 support for in cf5d3a8c.

ec_byte_read() ec_byte_read_from_end() had different return types.
ec_dec_bits() was storing its return value as int instead of
 ec_uint32, which will break if int is only 16 bits.

This simplifies a good bit of the error handling, and should make it
 impossible to overrun the buffer in the encoder or decoder, while
 still allowing tell() to operate correctly after a bust.
The encoder now tries to keep the range coder data intact after a
 bust instead of corrupting it with extra bits data, though this is
 not a guarantee (too many extra bits may have already been flushed).
It also now correctly reports errors when the bust occurs merging the
 last byte of range coder and extra bits.

A number of abstraction barrier violations were cleaned up, as well.
This patch also includes a number of minor performance improvements:
 ec_{enc|dec}_bits() in particular should be much faster.

Finally, tf_select was changed to be coded with the range coder
 rather than extra bits, so that it is at the front of the packet
 (for unequal error protection robustness).

Timothy B. Terriberry authored 14 years ago and Jean-Marc Valin committed 14 years ago

Provide direct implementations ec_{enc|dec}_bit_prob() that do not require a division instead of using the normal entropy coder path. This should be exactly equivalent to the existing code.

original ec_encode_bin()/ec_decode_bin() to optimize performance when ft is
a power of two.

Making it so all the information encoded directly with ec_enc_bits() gets
stored at the end of the stream, without going through the range coder. This
should be both faster and reduce the effects of bit errors.

Conflicts:

	tests/ectest.c

Signed-off-by: Timothy B. Terriberry <tterribe@xiph.org>

Timothy B. Terriberry authored 16 years ago and Jean-Marc Valin committed 16 years ago

When I removed the special case for EC_ILOG(0) in commit
 06390d08, it broke ec_dec_uint() with _ft=1
 (which should encode the value 0 using 0 bits).
This feature was tested by ectest.c, but not actually used by libcelt.
An assert has been added to ec_dec_uint() to ensure that we don't try to use
 this feature by accident.
ec_enc_uint() was actually correct, but support for this feature has been
 removed and the assert put in its place.

of range.

required) and using it in ec_{en|de}c_bits()

(and fix for celt_div with 16-bit numerator on a 16-bit CPU)

especially now that we have a custom version of that code anyway. Moved
the test code to tests/

tterribe authored 17 years ago and Jean-Marc Valin committed 17 years ago

Update ec_dec_bits64() to correspond to the new ec_enc_bits64(). Not sure why this wasn't committed before.

git-svn-id: http://svn.xiph.org/trunk/ghost@14409 0101bb08-14d6-0310-b084-bc0e0c8e3800

Updated broken paper URLs.
Cleaned up non-multiply-free range coder documentation (e.g., stop claiming
it's multiply-free).