Remove the EC_SMALLMUL experimental flag.
This experiment has been fully adopted and is now an integral part
of the draft AV1 bitstream definition.
objdump -d libaom.a gives identical output before and after this
patch.
Change-Id: I6f936f4b10de23a9471e0ccadf9cf178fb62be69
diff --git a/aom_dsp/entenc.c b/aom_dsp/entenc.c
index a350f27..b8c4dc0 100644
--- a/aom_dsp/entenc.c
+++ b/aom_dsp/entenc.c
@@ -143,11 +143,10 @@
}
/*Encodes a symbol given its frequency in Q15.
- fl: The cumulative frequency of all symbols that come before the one to be
- encoded.
- fh: The cumulative frequency of all symbols up to and including the one to
- be encoded.
- {EC_SMALLMUL} Both values are 32768 minus that.*/
+ fl: 32768 minus the cumulative frequency of all symbols that come before the
+ one to be encoded.
+ fh: 32768 minus the cumulative frequency of all symbols up to and including
+ the one to be encoded.*/
static void od_ec_encode_q15(od_ec_enc *enc, unsigned fl, unsigned fh) {
od_ec_window l;
unsigned r;
@@ -156,7 +155,6 @@
l = enc->low;
r = enc->rng;
OD_ASSERT(32768U <= r);
-#if CONFIG_EC_SMALLMUL
OD_ASSERT(fh < fl);
OD_ASSERT(fl <= 32768U);
if (fl < 32768U) {
@@ -167,14 +165,6 @@
} else {
r -= (r >> 8) * (uint32_t)fh >> 7;
}
-#else
- OD_ASSERT(fl < fh);
- OD_ASSERT(fh <= 32768U);
- u = fl * (uint32_t)r >> 15;
- v = fh * (uint32_t)r >> 15;
- r = v - u;
- l += u;
-#endif
od_ec_enc_normalize(enc, l, r);
#if OD_MEASURE_EC_OVERHEAD
enc->entropy -= OD_LOG2((double)(OD_ICDF(fh) - OD_ICDF(fl)) / 32768.);
@@ -184,8 +174,7 @@
/*Encode a single binary value.
val: The value to encode (0 or 1).
- {EC_SMALLMUL} f: The probability that the val is one, scaled by 32768.
- {else} f: The probability that val is zero, scaled by 32768.*/
+ f: The probability that the val is one, scaled by 32768.*/
void od_ec_encode_bool_q15(od_ec_enc *enc, int val, unsigned f) {
od_ec_window l;
unsigned r;
@@ -195,15 +184,9 @@
l = enc->low;
r = enc->rng;
OD_ASSERT(32768U <= r);
-#if CONFIG_EC_SMALLMUL
v = (r >> 8) * (uint32_t)f >> 7;
if (val) l += r - v;
r = val ? v : r - v;
-#else
- v = f * (uint32_t)r >> 15;
- if (val) l += v;
- r = val ? r - v : v;
-#endif
od_ec_enc_normalize(enc, l, r);
#if OD_MEASURE_EC_OVERHEAD
enc->entropy -=
@@ -214,19 +197,19 @@
/*Encodes a symbol given a cumulative distribution function (CDF) table in Q15.
s: The index of the symbol to encode.
- cdf: The CDF, such that symbol s falls in the range
- [s > 0 ? cdf[s - 1] : 0, cdf[s]).
- The values must be monotonically non-decreasing, and the last value
- must be exactly 32768.
+ icdf: 32768 minus the CDF, such that symbol s falls in the range
+ [s > 0 ? (32768 - icdf[s - 1]) : 0, 32768 - icdf[s]).
+ The values must be monotonically decreasing, and icdf[nsyms - 1] must
+ be 0.
nsyms: The number of symbols in the alphabet.
This should be at most 16.*/
-void od_ec_encode_cdf_q15(od_ec_enc *enc, int s, const uint16_t *cdf,
+void od_ec_encode_cdf_q15(od_ec_enc *enc, int s, const uint16_t *icdf,
int nsyms) {
(void)nsyms;
OD_ASSERT(s >= 0);
OD_ASSERT(s < nsyms);
- OD_ASSERT(cdf[nsyms - 1] == OD_ICDF(32768U));
- od_ec_encode_q15(enc, s > 0 ? cdf[s - 1] : OD_ICDF(0), cdf[s]);
+ OD_ASSERT(icdf[nsyms - 1] == OD_ICDF(32768U));
+ od_ec_encode_q15(enc, s > 0 ? icdf[s - 1] : OD_ICDF(0), icdf[s]);
}
#if CONFIG_RAWBITS
