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authorJens Arnold <amiconn@rockbox.org>2008-11-16 12:58:15 +0000
committerJens Arnold <amiconn@rockbox.org>2008-11-16 12:58:15 +0000
commitb5c0afc4423727cd790a970781cc4ece76211391 (patch)
tree0d0bf3d0c1df6bb96de15befa28e3bf7dccd958e /apps/codecs/demac/libdemac/rangecoding.h
parenta0584aec74379f43ee6f0a26c6a70be18ff32803 (diff)
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Move the contents of rangecoding.h into entropy.c, and remove the former. It was only used there, and defined some variables in the .h
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19116 a1c6a512-1295-4272-9138-f99709370657
Diffstat (limited to 'apps/codecs/demac/libdemac/rangecoding.h')
-rw-r--r--apps/codecs/demac/libdemac/rangecoding.h178
1 files changed, 0 insertions, 178 deletions
diff --git a/apps/codecs/demac/libdemac/rangecoding.h b/apps/codecs/demac/libdemac/rangecoding.h
deleted file mode 100644
index 645fd1a..0000000
--- a/apps/codecs/demac/libdemac/rangecoding.h
+++ /dev/null
@@ -1,178 +0,0 @@
-/*
-
-libdemac - A Monkey's Audio decoder
-
-$Id$
-
-Copyright (C) Dave Chapman 2007
-
-This program is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program; if not, write to the Free Software
-Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110, USA
-
-*/
-
-/*
-
-Range decoder adapted from rangecod.c included in:
-
- http://www.compressconsult.com/rangecoder/rngcod13.zip
-
- rangecod.c range encoding
-
- (c) Michael Schindler
- 1997, 1998, 1999, 2000
- http://www.compressconsult.com/
- michael@compressconsult.com
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
-
-The encoding functions were removed, and functions turned into "static
-inline" functions and moved to a .h file. Some minor cosmetic changes
-were made (e.g. turning pre-processor symbols into upper-case,
-removing the rc parameter from each function (and the RNGC macro)).
-
-
-*/
-
-#ifdef ROCKBOX
-#include "../lib/codeclib.h"
-/* for UDIV32() */
-#endif
-
-#ifndef UDIV32
-#define UDIV32(a, b) (a / b)
-#endif
-
-/* BITSTREAM READING FUNCTIONS */
-
-/* We deal with the input data one byte at a time - to ensure
- functionality on CPUs of any endianness regardless of any requirements
- for aligned reads.
-*/
-
-static unsigned char* bytebuffer IBSS_ATTR;
-static int bytebufferoffset IBSS_ATTR;
-
-static inline void skip_byte(void)
-{
- bytebufferoffset--;
- bytebuffer += bytebufferoffset & 4;
- bytebufferoffset &= 3;
-}
-
-static inline int read_byte(void)
-{
- int ch = bytebuffer[bytebufferoffset];
-
- skip_byte();
-
- return ch;
-}
-
-/* RANGE DECODING FUNCTIONS */
-
-/* SIZE OF RANGE ENCODING CODE VALUES. */
-
-#define CODE_BITS 32
-#define TOP_VALUE ((unsigned int)1 << (CODE_BITS-1))
-#define SHIFT_BITS (CODE_BITS - 9)
-#define EXTRA_BITS ((CODE_BITS-2) % 8 + 1)
-#define BOTTOM_VALUE (TOP_VALUE >> 8)
-
-struct rangecoder_t
-{
- uint32_t low; /* low end of interval */
- uint32_t range; /* length of interval */
- uint32_t help; /* bytes_to_follow resp. intermediate value */
- unsigned int buffer; /* buffer for input/output */
-};
-
-static struct rangecoder_t rc IBSS_ATTR;
-
-/* Start the decoder */
-static inline void range_start_decoding(void)
-{
- rc.buffer = read_byte();
- rc.low = rc.buffer >> (8 - EXTRA_BITS);
- rc.range = (uint32_t) 1 << EXTRA_BITS;
-}
-
-static inline void range_dec_normalize(void)
-{
- while (rc.range <= BOTTOM_VALUE)
- {
- rc.buffer = (rc.buffer << 8) | read_byte();
- rc.low = (rc.low << 8) | ((rc.buffer >> 1) & 0xff);
- rc.range <<= 8;
- }
-}
-
-/* Calculate culmulative frequency for next symbol. Does NO update!*/
-/* tot_f is the total frequency */
-/* or: totf is (code_value)1<<shift */
-/* returns the culmulative frequency */
-static inline int range_decode_culfreq(int tot_f)
-{
- range_dec_normalize();
- rc.help = UDIV32(rc.range, tot_f);
- return UDIV32(rc.low, rc.help);
-}
-
-static inline int range_decode_culshift(int shift)
-{
- range_dec_normalize();
- rc.help = rc.range >> shift;
- return UDIV32(rc.low, rc.help);
-}
-
-
-/* Update decoding state */
-/* sy_f is the interval length (frequency of the symbol) */
-/* lt_f is the lower end (frequency sum of < symbols) */
-static inline void range_decode_update(int sy_f, int lt_f)
-{
- rc.low -= rc.help * lt_f;
- rc.range = rc.help * sy_f;
-}
-
-
-/* Decode a byte/short without modelling */
-static inline unsigned char decode_byte(void)
-{ int tmp = range_decode_culshift(8);
- range_decode_update( 1,tmp);
- return tmp;
-}
-
-static inline int short range_decode_short(void)
-{ int tmp = range_decode_culshift(16);
- range_decode_update( 1,tmp);
- return tmp;
-}
-
-/* Decode n bits (n <= 16) without modelling - based on range_decode_short */
-static inline int range_decode_bits(int n)
-{ int tmp = range_decode_culshift(n);
- range_decode_update( 1,tmp);
- return tmp;
-}
-
-
-/* Finish decoding */
-static inline void range_done_decoding(void)
-{ range_dec_normalize(); /* normalize to use up all bytes */
-}