// Copyright 2011 Google Inc.
//
// This code is licensed under the same terms as WebM:
// Software License Agreement: http://www.webmproject.org/license/software/
// Additional IP Rights Grant: http://www.webmproject.org/license/additional/
// -----------------------------------------------------------------------------
//
// Bit writing and boolean coder
//
// Author: Skal (pascal.massimino@gmail.com)
#ifndef WEBP_ENC_BIT_WRITER_H_
#define WEBP_ENC_BIT_WRITER_H_
#include "vp8enci.h"
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif
//-----------------------------------------------------------------------------
// Bit-writing
typedef struct VP8BitWriter VP8BitWriter;
struct VP8BitWriter {
int32_t range_; // range-1
int32_t value_;
int run_; // number of outstanding bits
int nb_bits_; // number of pending bits
uint8_t* buf_;
size_t pos_;
size_t max_pos_;
int error_; // true in case of error
};
int VP8BitWriterInit(VP8BitWriter* const bw, size_t expected_size);
uint8_t* VP8BitWriterFinish(VP8BitWriter* const bw);
int VP8PutBit(VP8BitWriter* const bw, int bit, int prob);
int VP8PutBitUniform(VP8BitWriter* const bw, int bit);
void VP8PutValue(VP8BitWriter* const bw, int value, int nb_bits);
void VP8PutSignedValue(VP8BitWriter* const bw, int value, int nb_bits);
int VP8BitWriterAppend(VP8BitWriter* const bw,
const uint8_t* data, size_t size);
// return approximate write position (in bits)
static inline uint64_t VP8BitWriterPos(const VP8BitWriter* const bw) {
return (uint64_t)(bw->pos_ + bw->run_) * 8 + 8 + bw->nb_bits_;
}
static inline uint8_t* VP8BitWriterBuf(const VP8BitWriter* const bw) {
return bw->buf_;
}
static inline size_t VP8BitWriterSize(const VP8BitWriter* const bw) {
return bw->pos_;
}
//-----------------------------------------------------------------------------
#if defined(__cplusplus) || defined(c_plusplus)
} // extern "C"
#endif
#endif // WEBP_ENC_BIT_WRITER_H_