vpx/vp9/encoder/vp9_write_bit_buffer.h
Dmitry Kovalev 18c83b3714 Compressed/uncompressed frame header changes.
Adding API to read/write uncompressed frame header bits (it is not final
yet). Separate functions to read/write uncompressed header. Moving
clr_type, error_resilient_mode, refresh_frame_context,
frame_parallel_decoding_mode, frame_context_idx from compressed partition
to uncompressed frame header.

Change-Id: Id3ed8a387980c652ae147549412f4ec24a0a5bd0
2013-05-28 18:07:54 -07:00

43 lines
1.2 KiB
C

/*
* Copyright (c) 2013 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef VP9_BIT_WRITE_BUFFER_H_
#define VP9_BIT_WRITE_BUFFER_H_
#include "vpx/vpx_integer.h"
struct vp9_write_bit_buffer {
uint8_t *bit_buffer;
size_t bit_offset;
};
static size_t vp9_rb_bytes_written(struct vp9_write_bit_buffer *wb) {
return wb->bit_offset / CHAR_BIT + (wb->bit_offset % CHAR_BIT > 0);
}
static void vp9_wb_write_bit(struct vp9_write_bit_buffer *wb, int bit) {
const int off = wb->bit_offset;
const int p = off / CHAR_BIT;
const int q = CHAR_BIT - 1 - off % CHAR_BIT;
wb->bit_buffer[p] &= ~(1 << q);
wb->bit_buffer[p] |= bit << q;
wb->bit_offset = off + 1;
}
static void vp9_wb_write_literal(struct vp9_write_bit_buffer *wb,
int data, int bits) {
int bit;
for (bit = bits - 1; bit >= 0; bit--)
vp9_wb_write_bit(wb, (data >> bit) & 1);
}
#endif // VP9_BIT_WRITE_BUFFER_H_