2 * Copyright (c) 2013 The WebM project authors. All Rights Reserved.
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
11 #ifndef VP9_ENCODER_VP9_WRITE_BIT_BUFFER_H_
12 #define VP9_ENCODER_VP9_WRITE_BIT_BUFFER_H_
16 #include "vpx/vpx_integer.h"
22 struct vp9_write_bit_buffer {
27 static size_t vp9_rb_bytes_written(struct vp9_write_bit_buffer *wb) {
28 return wb->bit_offset / CHAR_BIT + (wb->bit_offset % CHAR_BIT > 0);
31 static void vp9_wb_write_bit(struct vp9_write_bit_buffer *wb, int bit) {
32 const int off = wb->bit_offset;
33 const int p = off / CHAR_BIT;
34 const int q = CHAR_BIT - 1 - off % CHAR_BIT;
35 if (q == CHAR_BIT -1) {
36 wb->bit_buffer[p] = bit << q;
38 wb->bit_buffer[p] &= ~(1 << q);
39 wb->bit_buffer[p] |= bit << q;
41 wb->bit_offset = off + 1;
44 static void vp9_wb_write_literal(struct vp9_write_bit_buffer *wb,
47 for (bit = bits - 1; bit >= 0; bit--)
48 vp9_wb_write_bit(wb, (data >> bit) & 1);
56 #endif // VP9_ENCODER_VP9_WRITE_BIT_BUFFER_H_