diff options
Diffstat (limited to 'ffmpeg1/libavcodec/dirac_arith.h')
| -rw-r--r-- | ffmpeg1/libavcodec/dirac_arith.h | 190 |
1 files changed, 0 insertions, 190 deletions
diff --git a/ffmpeg1/libavcodec/dirac_arith.h b/ffmpeg1/libavcodec/dirac_arith.h deleted file mode 100644 index f9a8bba..0000000 --- a/ffmpeg1/libavcodec/dirac_arith.h +++ /dev/null @@ -1,190 +0,0 @@ -/* - * Copyright (C) 2007 Marco Gerards <marco@gnu.org> - * Copyright (C) 2009 David Conrad - * - * This file is part of FFmpeg. - * - * FFmpeg is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public - * License as published by the Free Software Foundation; either - * version 2.1 of the License, or (at your option) any later version. - * - * FFmpeg is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with FFmpeg; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA - */ - -/** - * @file - * Arithmetic decoder for Dirac - * @author Marco Gerards <marco@gnu.org> - */ - -#ifndef AVCODEC_DIRAC_ARITH_H -#define AVCODEC_DIRAC_ARITH_H - -#include "bytestream.h" -#include "get_bits.h" - -enum dirac_arith_contexts { - CTX_ZPZN_F1, - CTX_ZPNN_F1, - CTX_NPZN_F1, - CTX_NPNN_F1, - CTX_ZP_F2, - CTX_ZP_F3, - CTX_ZP_F4, - CTX_ZP_F5, - CTX_ZP_F6, - CTX_NP_F2, - CTX_NP_F3, - CTX_NP_F4, - CTX_NP_F5, - CTX_NP_F6, - CTX_COEFF_DATA, - CTX_SIGN_NEG, - CTX_SIGN_ZERO, - CTX_SIGN_POS, - CTX_ZERO_BLOCK, - CTX_DELTA_Q_F, - CTX_DELTA_Q_DATA, - CTX_DELTA_Q_SIGN, - - DIRAC_CTX_COUNT -}; - -// Dirac resets the arith decoder between decoding various types of data, -// so many contexts are never used simultaneously. Thus, we can reduce -// the number of contexts needed by reusing them. -#define CTX_SB_F1 CTX_ZP_F5 -#define CTX_SB_DATA 0 -#define CTX_PMODE_REF1 0 -#define CTX_PMODE_REF2 1 -#define CTX_GLOBAL_BLOCK 2 -#define CTX_MV_F1 CTX_ZP_F2 -#define CTX_MV_DATA 0 -#define CTX_DC_F1 CTX_ZP_F5 -#define CTX_DC_DATA 0 - -typedef struct { - unsigned low; - uint16_t range; - int16_t counter; - - const uint8_t *bytestream; - const uint8_t *bytestream_end; - - uint16_t contexts[DIRAC_CTX_COUNT]; -} DiracArith; - -extern const uint8_t ff_dirac_next_ctx[DIRAC_CTX_COUNT]; -extern const uint16_t ff_dirac_prob[256]; -extern int16_t ff_dirac_prob_branchless[256][2]; - -static inline void renorm(DiracArith *c) -{ -#if HAVE_FAST_CLZ - int shift = 14 - av_log2_16bit(c->range-1) + ((c->range-1)>>15); - - c->low <<= shift; - c->range <<= shift; - c->counter += shift; -#else - while (c->range <= 0x4000) { - c->low <<= 1; - c->range <<= 1; - c->counter++; - } -#endif -} - -static inline void refill(DiracArith *c) -{ - int counter = c->counter; - - if (counter >= 0) { - int new = bytestream_get_be16(&c->bytestream); - - // the spec defines overread bits to be 1, and streams rely on this - if (c->bytestream > c->bytestream_end) { - new |= 0xff; - if (c->bytestream > c->bytestream_end+1) - new |= 0xff00; - - c->bytestream = c->bytestream_end; - } - - c->low += new << counter; - counter -= 16; - } - c->counter = counter; -} - -static inline int dirac_get_arith_bit(DiracArith *c, int ctx) -{ - int prob_zero = c->contexts[ctx]; - int range_times_prob, bit; - unsigned low = c->low; - int range = c->range; - - range_times_prob = (c->range * prob_zero) >> 16; - -#if HAVE_FAST_CMOV && HAVE_INLINE_ASM - low -= range_times_prob << 16; - range -= range_times_prob; - bit = 0; - __asm__( - "cmpl %5, %4 \n\t" - "setae %b0 \n\t" - "cmovb %3, %2 \n\t" - "cmovb %5, %1 \n\t" - : "+q"(bit), "+r"(range), "+r"(low) - : "r"(c->low), "r"(c->low>>16), - "r"(range_times_prob) - ); -#else - bit = (low >> 16) >= range_times_prob; - if (bit) { - low -= range_times_prob << 16; - range -= range_times_prob; - } else { - range = range_times_prob; - } -#endif - - c->contexts[ctx] += ff_dirac_prob_branchless[prob_zero>>8][bit]; - c->low = low; - c->range = range; - - renorm(c); - refill(c); - return bit; -} - -static inline int dirac_get_arith_uint(DiracArith *c, int follow_ctx, int data_ctx) -{ - int ret = 1; - while (!dirac_get_arith_bit(c, follow_ctx)) { - ret <<= 1; - ret += dirac_get_arith_bit(c, data_ctx); - follow_ctx = ff_dirac_next_ctx[follow_ctx]; - } - return ret-1; -} - -static inline int dirac_get_arith_int(DiracArith *c, int follow_ctx, int data_ctx) -{ - int ret = dirac_get_arith_uint(c, follow_ctx, data_ctx); - if (ret && dirac_get_arith_bit(c, data_ctx+1)) - ret = -ret; - return ret; -} - -void ff_dirac_init_arith_decoder(DiracArith *c, GetBitContext *gb, int length); - -#endif /* AVCODEC_DIRAC_ARITH_H */ |