summaryrefslogtreecommitdiffstats
path: root/third_party/aom/aom_dsp/binary_codes_reader.c
diff options
context:
space:
mode:
Diffstat (limited to 'third_party/aom/aom_dsp/binary_codes_reader.c')
-rw-r--r--third_party/aom/aom_dsp/binary_codes_reader.c49
1 files changed, 46 insertions, 3 deletions
diff --git a/third_party/aom/aom_dsp/binary_codes_reader.c b/third_party/aom/aom_dsp/binary_codes_reader.c
index bf304dada..4f38afbc5 100644
--- a/third_party/aom/aom_dsp/binary_codes_reader.c
+++ b/third_party/aom/aom_dsp/binary_codes_reader.c
@@ -53,6 +53,15 @@ uint16_t aom_read_primitive_quniform_(aom_reader *r,
return v < m ? v : (v << 1) - m + aom_read_bit(r, ACCT_STR_NAME);
}
+static uint16_t aom_rb_read_primitive_quniform(struct aom_read_bit_buffer *rb,
+ uint16_t n) {
+ if (n <= 1) return 0;
+ const int l = get_msb(n - 1) + 1;
+ const int m = (1 << l) - n;
+ const int v = aom_rb_read_literal(rb, l - 1);
+ return v < m ? v : (v << 1) - m + aom_rb_read_bit(rb);
+}
+
uint16_t aom_read_primitive_refbilevel_(aom_reader *r, uint16_t n, uint16_t p,
uint16_t ref ACCT_STR_PARAM) {
if (n <= 1) return 0;
@@ -101,15 +110,42 @@ uint16_t aom_read_primitive_subexpfin_(aom_reader *r, uint16_t n,
return v;
}
-// Decode finite subexponential code that for a symbol v in [0, n-1] with
-// parameter k
-// based on a reference ref also in [0, n-1].
+static uint16_t aom_rb_read_primitive_subexpfin(struct aom_read_bit_buffer *rb,
+ uint16_t n, uint16_t k) {
+ int i = 0;
+ int mk = 0;
+ uint16_t v;
+ while (1) {
+ int b = (i ? k + i - 1 : k);
+ int a = (1 << b);
+ if (n <= mk + 3 * a) {
+ v = aom_rb_read_primitive_quniform(rb, n - mk) + mk;
+ break;
+ } else {
+ if (aom_rb_read_bit(rb)) {
+ i = i + 1;
+ mk += a;
+ } else {
+ v = aom_rb_read_literal(rb, b) + mk;
+ break;
+ }
+ }
+ }
+ return v;
+}
+
uint16_t aom_read_primitive_refsubexpfin_(aom_reader *r, uint16_t n, uint16_t k,
uint16_t ref ACCT_STR_PARAM) {
return inv_recenter_finite_nonneg(
n, ref, aom_read_primitive_subexpfin(r, n, k, ACCT_STR_NAME));
}
+static uint16_t aom_rb_read_primitive_refsubexpfin(
+ struct aom_read_bit_buffer *rb, uint16_t n, uint16_t k, uint16_t ref) {
+ return inv_recenter_finite_nonneg(n, ref,
+ aom_rb_read_primitive_subexpfin(rb, n, k));
+}
+
// Decode finite subexponential code that for a symbol v in [-(n-1), n-1] with
// parameter k based on a reference ref also in [-(n-1), n-1].
int16_t aom_read_signed_primitive_refsubexpfin_(aom_reader *r, uint16_t n,
@@ -120,3 +156,10 @@ int16_t aom_read_signed_primitive_refsubexpfin_(aom_reader *r, uint16_t n,
return aom_read_primitive_refsubexpfin(r, scaled_n, k, ref, ACCT_STR_NAME) -
n + 1;
}
+
+int16_t aom_rb_read_signed_primitive_refsubexpfin(
+ struct aom_read_bit_buffer *rb, uint16_t n, uint16_t k, int16_t ref) {
+ ref += n - 1;
+ const uint16_t scaled_n = (n << 1) - 1;
+ return aom_rb_read_primitive_refsubexpfin(rb, scaled_n, k, ref) - n + 1;
+}