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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 09:22:09 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 09:22:09 +0000 |
commit | 43a97878ce14b72f0981164f87f2e35e14151312 (patch) | |
tree | 620249daf56c0258faa40cbdcf9cfba06de2a846 /third_party/aom/aom_dsp/binary_codes_reader.c | |
parent | Initial commit. (diff) | |
download | firefox-43a97878ce14b72f0981164f87f2e35e14151312.tar.xz firefox-43a97878ce14b72f0981164f87f2e35e14151312.zip |
Adding upstream version 110.0.1.upstream/110.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/aom/aom_dsp/binary_codes_reader.c')
-rw-r--r-- | third_party/aom/aom_dsp/binary_codes_reader.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/third_party/aom/aom_dsp/binary_codes_reader.c b/third_party/aom/aom_dsp/binary_codes_reader.c new file mode 100644 index 0000000000..01088010a1 --- /dev/null +++ b/third_party/aom/aom_dsp/binary_codes_reader.c @@ -0,0 +1,123 @@ +/* + * Copyright (c) 2017, Alliance for Open Media. All rights reserved + * + * This source code is subject to the terms of the BSD 2 Clause License and + * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License + * was not distributed with this source code in the LICENSE file, you can + * obtain it at www.aomedia.org/license/software. If the Alliance for Open + * Media Patent License 1.0 was not distributed with this source code in the + * PATENTS file, you can obtain it at www.aomedia.org/license/patent. + */ + +#include "aom_dsp/binary_codes_reader.h" + +#include "av1/common/common.h" + +// Inverse recenters a non-negative literal v around a reference r +static uint16_t inv_recenter_nonneg(uint16_t r, uint16_t v) { + if (v > (r << 1)) + return v; + else if ((v & 1) == 0) + return (v >> 1) + r; + else + return r - ((v + 1) >> 1); +} + +// Inverse recenters a non-negative literal v in [0, n-1] around a +// reference r also in [0, n-1] +static uint16_t inv_recenter_finite_nonneg(uint16_t n, uint16_t r, uint16_t v) { + if ((r << 1) <= n) { + return inv_recenter_nonneg(r, v); + } else { + return n - 1 - inv_recenter_nonneg(n - 1 - r, v); + } +} + +uint16_t aom_read_primitive_quniform_(aom_reader *r, + uint16_t n ACCT_STR_PARAM) { + if (n <= 1) return 0; + const int l = get_msb(n) + 1; + const int m = (1 << l) - n; + const int v = aom_read_literal(r, l - 1, ACCT_STR_NAME); + 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; + 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); +} + +// Decode finite subexponential code that for a symbol v in [0, n-1] with +// parameter k +uint16_t aom_read_primitive_subexpfin_(aom_reader *r, uint16_t n, + uint16_t k ACCT_STR_PARAM) { + int i = 0; + int mk = 0; + + while (1) { + int b = (i ? k + i - 1 : k); + int a = (1 << b); + + if (n <= mk + 3 * a) { + return aom_read_primitive_quniform(r, n - mk, ACCT_STR_NAME) + mk; + } + + if (!aom_read_bit(r, ACCT_STR_NAME)) { + return aom_read_literal(r, b, ACCT_STR_NAME) + mk; + } + + i = i + 1; + mk += a; + } + + assert(0); + return 0; +} + +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; + + while (1) { + int b = (i ? k + i - 1 : k); + int a = (1 << b); + + if (n <= mk + 3 * a) { + return aom_rb_read_primitive_quniform(rb, n - mk) + mk; + } + + if (!aom_rb_read_bit(rb)) { + return aom_rb_read_literal(rb, b) + mk; + } + + i = i + 1; + mk += a; + } + + assert(0); + return 0; +} + +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)); +} + +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; +} |