1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libvpx/vp9/encoder/vp9_write_bit_buffer.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,48 @@
1.4 +/*
1.5 + * Copyright (c) 2013 The WebM project authors. All Rights Reserved.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license
1.8 + * that can be found in the LICENSE file in the root of the source
1.9 + * tree. An additional intellectual property rights grant can be found
1.10 + * in the file PATENTS. All contributing project authors may
1.11 + * be found in the AUTHORS file in the root of the source tree.
1.12 + */
1.13 +
1.14 +#ifndef VP9_BIT_WRITE_BUFFER_H_
1.15 +#define VP9_BIT_WRITE_BUFFER_H_
1.16 +
1.17 +#include <limits.h>
1.18 +
1.19 +#include "vpx/vpx_integer.h"
1.20 +
1.21 +struct vp9_write_bit_buffer {
1.22 + uint8_t *bit_buffer;
1.23 + size_t bit_offset;
1.24 +};
1.25 +
1.26 +static size_t vp9_rb_bytes_written(struct vp9_write_bit_buffer *wb) {
1.27 + return wb->bit_offset / CHAR_BIT + (wb->bit_offset % CHAR_BIT > 0);
1.28 +}
1.29 +
1.30 +static void vp9_wb_write_bit(struct vp9_write_bit_buffer *wb, int bit) {
1.31 + const int off = wb->bit_offset;
1.32 + const int p = off / CHAR_BIT;
1.33 + const int q = CHAR_BIT - 1 - off % CHAR_BIT;
1.34 + if (q == CHAR_BIT -1) {
1.35 + wb->bit_buffer[p] = bit << q;
1.36 + } else {
1.37 + wb->bit_buffer[p] &= ~(1 << q);
1.38 + wb->bit_buffer[p] |= bit << q;
1.39 + }
1.40 + wb->bit_offset = off + 1;
1.41 +}
1.42 +
1.43 +static void vp9_wb_write_literal(struct vp9_write_bit_buffer *wb,
1.44 + int data, int bits) {
1.45 + int bit;
1.46 + for (bit = bits - 1; bit >= 0; bit--)
1.47 + vp9_wb_write_bit(wb, (data >> bit) & 1);
1.48 +}
1.49 +
1.50 +
1.51 +#endif // VP9_BIT_WRITE_BUFFER_H_
