1 /* 2 * Copyright (c) 2013 The WebM project authors. All Rights Reserved. 3 * 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. 9 */ 10 11 #include <limits.h> 12 #include "vp9/encoder/vp9_write_bit_buffer.h" 13 vp9_wb_bytes_written(const struct vp9_write_bit_buffer * wb)14size_t vp9_wb_bytes_written(const struct vp9_write_bit_buffer *wb) { 15 return wb->bit_offset / CHAR_BIT + (wb->bit_offset % CHAR_BIT > 0); 16 } 17 vp9_wb_write_bit(struct vp9_write_bit_buffer * wb,int bit)18void vp9_wb_write_bit(struct vp9_write_bit_buffer *wb, int bit) { 19 const int off = (int)wb->bit_offset; 20 const int p = off / CHAR_BIT; 21 const int q = CHAR_BIT - 1 - off % CHAR_BIT; 22 if (q == CHAR_BIT -1) { 23 wb->bit_buffer[p] = bit << q; 24 } else { 25 wb->bit_buffer[p] &= ~(1 << q); 26 wb->bit_buffer[p] |= bit << q; 27 } 28 wb->bit_offset = off + 1; 29 } 30 vp9_wb_write_literal(struct vp9_write_bit_buffer * wb,int data,int bits)31void vp9_wb_write_literal(struct vp9_write_bit_buffer *wb, int data, int bits) { 32 int bit; 33 for (bit = bits - 1; bit >= 0; bit--) 34 vp9_wb_write_bit(wb, (data >> bit) & 1); 35 } 36