| /* |
| * Copyright (c) 2001-2016, 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_AOM_DSP_ENTENC_H_ |
| #define AOM_AOM_DSP_ENTENC_H_ |
| #include <stddef.h> |
| #include "aom_dsp/entcode.h" |
| #include "aom_util/endian_inl.h" |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| typedef uint64_t od_ec_enc_window; |
| |
| typedef struct od_ec_enc od_ec_enc; |
| |
| #define OD_MEASURE_EC_OVERHEAD (0) |
| |
| /*The entropy encoder context.*/ |
| struct od_ec_enc { |
| /*Buffered output. |
| This contains only the raw bits until the final call to od_ec_enc_done(), |
| where all the arithmetic-coded data gets prepended to it.*/ |
| unsigned char *buf; |
| /*The size of the buffer.*/ |
| uint32_t storage; |
| /*The offset at which the next entropy-coded byte will be written.*/ |
| uint32_t offs; |
| /*The low end of the current range.*/ |
| od_ec_enc_window low; |
| /*The number of values in the current range.*/ |
| uint16_t rng; |
| /*The number of bits of data in the current value.*/ |
| int16_t cnt; |
| /*Nonzero if an error occurred.*/ |
| int error; |
| #if OD_MEASURE_EC_OVERHEAD |
| double entropy; |
| int nb_symbols; |
| #endif |
| }; |
| |
| /*See entenc.c for further documentation.*/ |
| |
| void od_ec_enc_init(od_ec_enc *enc, uint32_t size) OD_ARG_NONNULL(1); |
| void od_ec_enc_reset(od_ec_enc *enc) OD_ARG_NONNULL(1); |
| void od_ec_enc_clear(od_ec_enc *enc) OD_ARG_NONNULL(1); |
| |
| void od_ec_encode_bool_q15(od_ec_enc *enc, int val, unsigned f_q15) |
| OD_ARG_NONNULL(1); |
| void od_ec_encode_cdf_q15(od_ec_enc *enc, int s, const uint16_t *cdf, int nsyms) |
| OD_ARG_NONNULL(1) OD_ARG_NONNULL(3); |
| |
| void od_ec_enc_bits(od_ec_enc *enc, uint32_t fl, unsigned ftb) |
| OD_ARG_NONNULL(1); |
| |
| void od_ec_enc_patch_initial_bits(od_ec_enc *enc, unsigned val, int nbits) |
| OD_ARG_NONNULL(1); |
| OD_WARN_UNUSED_RESULT unsigned char *od_ec_enc_done(od_ec_enc *enc, |
| uint32_t *nbytes) |
| OD_ARG_NONNULL(1) OD_ARG_NONNULL(2); |
| |
| OD_WARN_UNUSED_RESULT int od_ec_enc_tell(const od_ec_enc *enc) |
| OD_ARG_NONNULL(1); |
| OD_WARN_UNUSED_RESULT uint32_t od_ec_enc_tell_frac(const od_ec_enc *enc) |
| OD_ARG_NONNULL(1); |
| |
| // buf is the frame bitbuffer, offs is where carry to be added |
| static inline void propagate_carry_bwd(unsigned char *buf, uint32_t offs) { |
| uint16_t sum, carry = 1; |
| do { |
| sum = (uint16_t)buf[offs] + 1; |
| buf[offs--] = (unsigned char)sum; |
| carry = sum >> 8; |
| } while (carry); |
| } |
| |
| // Convert to big-endian byte order and write data to buffer adding the |
| // carry-bit |
| static inline void write_enc_data_to_out_buf(unsigned char *out, uint32_t offs, |
| uint64_t output, uint64_t carry, |
| uint32_t *enc_offs, |
| uint8_t num_bytes_ready) { |
| const uint64_t reg = HToBE64(output << ((8 - num_bytes_ready) << 3)); |
| memcpy(&out[offs], ®, 8); |
| // Propagate carry backwards if exists |
| if (carry) { |
| assert(offs > 0); |
| propagate_carry_bwd(out, offs - 1); |
| } |
| *enc_offs = offs + num_bytes_ready; |
| } |
| |
| #ifdef __cplusplus |
| } // extern "C" |
| #endif |
| |
| #endif // AOM_AOM_DSP_ENTENC_H_ |