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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/aom/aom_dsp/bitreader_buffer.c
parentInitial commit. (diff)
downloadfirefox-esr-upstream.tar.xz
firefox-esr-upstream.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/aom/aom_dsp/bitreader_buffer.c')
-rw-r--r--third_party/aom/aom_dsp/bitreader_buffer.c67
1 files changed, 67 insertions, 0 deletions
diff --git a/third_party/aom/aom_dsp/bitreader_buffer.c b/third_party/aom/aom_dsp/bitreader_buffer.c
new file mode 100644
index 0000000000..b532117849
--- /dev/null
+++ b/third_party/aom/aom_dsp/bitreader_buffer.c
@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2016, 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 <assert.h>
+
+#include "config/aom_config.h"
+
+#include "aom_dsp/bitreader_buffer.h"
+
+size_t aom_rb_bytes_read(const struct aom_read_bit_buffer *rb) {
+ return (rb->bit_offset + 7) >> 3;
+}
+
+int aom_rb_read_bit(struct aom_read_bit_buffer *rb) {
+ const uint32_t off = rb->bit_offset;
+ const uint32_t p = off >> 3;
+ const int q = 7 - (int)(off & 0x7);
+ if (rb->bit_buffer + p < rb->bit_buffer_end) {
+ const int bit = (rb->bit_buffer[p] >> q) & 1;
+ rb->bit_offset = off + 1;
+ return bit;
+ } else {
+ if (rb->error_handler) rb->error_handler(rb->error_handler_data);
+ return 0;
+ }
+}
+
+int aom_rb_read_literal(struct aom_read_bit_buffer *rb, int bits) {
+ assert(bits <= 31);
+ int value = 0, bit;
+ for (bit = bits - 1; bit >= 0; bit--) value |= aom_rb_read_bit(rb) << bit;
+ return value;
+}
+
+uint32_t aom_rb_read_unsigned_literal(struct aom_read_bit_buffer *rb,
+ int bits) {
+ assert(bits <= 32);
+ uint32_t value = 0;
+ int bit;
+ for (bit = bits - 1; bit >= 0; bit--)
+ value |= (uint32_t)aom_rb_read_bit(rb) << bit;
+ return value;
+}
+
+int aom_rb_read_inv_signed_literal(struct aom_read_bit_buffer *rb, int bits) {
+ const int nbits = sizeof(unsigned) * 8 - bits - 1;
+ const unsigned value = (unsigned)aom_rb_read_literal(rb, bits + 1) << nbits;
+ return ((int)value) >> nbits;
+}
+
+uint32_t aom_rb_read_uvlc(struct aom_read_bit_buffer *rb) {
+ int leading_zeros = 0;
+ while (!aom_rb_read_bit(rb)) ++leading_zeros;
+ // Maximum 32 bits.
+ if (leading_zeros >= 32) return UINT32_MAX;
+ const uint32_t base = (1u << leading_zeros) - 1;
+ const uint32_t value = aom_rb_read_literal(rb, leading_zeros);
+ return base + value;
+}