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Diffstat (limited to 'third_party/aom/aom_dsp/ans.h')
-rw-r--r-- | third_party/aom/aom_dsp/ans.h | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/third_party/aom/aom_dsp/ans.h b/third_party/aom/aom_dsp/ans.h new file mode 100644 index 000000000..a7a2f0eab --- /dev/null +++ b/third_party/aom/aom_dsp/ans.h @@ -0,0 +1,44 @@ +/* + * Copyright (c) 2016, Alliance for Open Media. All rights reserved + * + * This source code is subject to the terms of the BSD 2 Clause License and + * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License + * was not distributed with this source code in the LICENSE file, you can + * obtain it at www.aomedia.org/license/software. If the Alliance for Open + * Media Patent License 1.0 was not distributed with this source code in the + * PATENTS file, you can obtain it at www.aomedia.org/license/patent. + */ + +#ifndef AOM_DSP_ANS_H_ +#define AOM_DSP_ANS_H_ +// Constants, types and utilities for Asymmetric Numeral Systems +// http://arxiv.org/abs/1311.2540v2 + +#include <assert.h> +#include "./aom_config.h" +#include "aom/aom_integer.h" +#include "aom_dsp/prob.h" + +#ifdef __cplusplus +extern "C" { +#endif // __cplusplus + +// Use windowed ANS, size is passed in at initialization +#define ANS_MAX_SYMBOLS 1 +#define ANS_REVERSE 1 + +typedef uint8_t AnsP8; +#define ANS_P8_PRECISION 256u +#define ANS_P8_SHIFT 8 +#define RANS_PROB_BITS 15 +#define RANS_PRECISION (1u << RANS_PROB_BITS) + +// L_BASE is the ANS base state. L_BASE % PRECISION must be 0. +#define L_BASE (1u << 17) +#define IO_BASE 256 +// Range I = { L_BASE, L_BASE + 1, ..., L_BASE * IO_BASE - 1 } + +#ifdef __cplusplus +} // extern "C" +#endif // __cplusplus +#endif // AOM_DSP_ANS_H_ |