ref: a2012d8dc5af8e0db693eb42992f510d61288447
dir: /libcelt/rate.h/
/* (C) 2007-2008 Jean-Marc Valin, CSIRO
*/
/*
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef RATE_H
#define RATE_H
#define MAX_PULSES 128
#define LOG_MAX_PULSES 7
#define BITRES 4
#define BITROUND 8
#define BITOVERFLOW 30000
static inline int bits2pulses(const CELTMode *m, const celt_int16_t *cache, int bits)
{
int i;
int lo, hi;
lo = 0;
hi = MAX_PULSES-1;
/* Instead of using the "bisection condition" we use a fixed number of
iterations because it should be faster */
/*while (hi-lo != 1)*/
for (i=0;i<LOG_MAX_PULSES;i++)
{
int mid = (lo+hi)>>1;
/* OPT: Make sure this is implemented with a conditional move */
if (cache[mid] >= bits)
hi = mid;
else
lo = mid;
}
if (bits-cache[lo] <= cache[hi]-bits)
return lo;
else
return hi;
}
/** Computes a cache of the pulses->bits mapping in each band */
celt_int16_t **compute_alloc_cache(CELTMode *m, int C);
/** Compute the pulse allocation, i.e. how many pulses will go in each
* band.
@param m mode
@param offsets Requested increase or decrease in the number of bits for
each band
@param total Number of bands
@param pulses Number of pulses per band (returned)
@return Total number of bits allocated
*/
void compute_allocation(const CELTMode *m, int *offsets, const int *stereo_mode, int total, int *pulses, int *ebits);
#endif