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-rw-r--r--libavcodec/bitstream.h344
1 files changed, 0 insertions, 344 deletions
diff --git a/libavcodec/bitstream.h b/libavcodec/bitstream.h
deleted file mode 100644
index 1b23cb2fa7..0000000000
--- a/libavcodec/bitstream.h
+++ /dev/null
@@ -1,344 +0,0 @@
-/*
- * Copyright (c) 2016 Alexandra Hájková
- *
- * This file is part of Libav.
- *
- * Libav 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.
- *
- * Libav 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 Libav; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-/**
- * @file
- * functions for reading bits from a buffer
- */
-
-#ifndef AVCODEC_BITSTREAM_H
-#define AVCODEC_BITSTREAM_H
-
-#include <stdint.h>
-
-#include "libavutil/common.h"
-#include "libavutil/intreadwrite.h"
-#include "libavutil/log.h"
-
-#include "mathops.h"
-
-typedef struct BitstreamContext {
- uint64_t bits; // stores bits read from the buffer
- const uint8_t *buffer, *buffer_end;
- const uint8_t *ptr; // position inside a buffer
- unsigned bits_left; // number of bits left in bits field
- unsigned size_in_bits;
-} BitstreamContext;
-
-static inline void refill_64(BitstreamContext *bc)
-{
- if (bc->ptr >= bc->buffer_end)
- return;
-
-#ifdef BITSTREAM_READER_LE
- bc->bits = AV_RL64(bc->ptr);
-#else
- bc->bits = AV_RB64(bc->ptr);
-#endif
- bc->ptr += 8;
- bc->bits_left = 64;
-}
-
-static inline void refill_32(BitstreamContext *bc)
-{
- if (bc->ptr >= bc->buffer_end)
- return;
-
-#ifdef BITSTREAM_READER_LE
- bc->bits = (uint64_t)AV_RL32(bc->ptr) << bc->bits_left | bc->bits;
-#else
- bc->bits = bc->bits | (uint64_t)AV_RB32(bc->ptr) << (32 - bc->bits_left);
-#endif
- bc->ptr += 4;
- bc->bits_left += 32;
-}
-
-/* Initialize BitstreamContext. Input buffer must have an additional zero
- * padding of AV_INPUT_BUFFER_PADDING_SIZE bytes at the end. */
-static inline int bitstream_init(BitstreamContext *bc, const uint8_t *buffer,
- unsigned bit_size)
-{
- unsigned buffer_size;
-
- if (bit_size > INT_MAX - 7 || !buffer) {
- buffer =
- bc->buffer =
- bc->ptr = NULL;
- bc->bits_left = 0;
- return AVERROR_INVALIDDATA;
- }
-
- buffer_size = (bit_size + 7) >> 3;
-
- bc->buffer = buffer;
- bc->buffer_end = buffer + buffer_size;
- bc->ptr = bc->buffer;
- bc->size_in_bits = bit_size;
- bc->bits_left = 0;
- bc->bits = 0;
-
- refill_64(bc);
-
- return 0;
-}
-
-/* Initialize BitstreamContext with buffer size in bytes instead of bits. */
-static inline int bitstream_init8(BitstreamContext *bc, const uint8_t *buffer,
- unsigned byte_size)
-{
- if (byte_size > INT_MAX / 8)
- return AVERROR_INVALIDDATA;
- return bitstream_init(bc, buffer, byte_size * 8);
-}
-
-/* Return number of bits already read. */
-static inline int bitstream_tell(const BitstreamContext *bc)
-{
- return (bc->ptr - bc->buffer) * 8 - bc->bits_left;
-}
-
-/* Return buffer size in bits. */
-static inline int bitstream_tell_size(const BitstreamContext *bc)
-{
- return bc->size_in_bits;
-}
-
-/* Return the number of the bits left in a buffer. */
-static inline int bitstream_bits_left(const BitstreamContext *bc)
-{
- return (bc->buffer - bc->ptr) * 8 + bc->size_in_bits + bc->bits_left;
-}
-
-static inline uint64_t get_val(BitstreamContext *bc, unsigned n)
-{
-#ifdef BITSTREAM_READER_LE
- uint64_t ret = bc->bits & ((UINT64_C(1) << n) - 1);
- bc->bits >>= n;
-#else
- uint64_t ret = bc->bits >> (64 - n);
- bc->bits <<= n;
-#endif
- bc->bits_left -= n;
-
- return ret;
-}
-
-/* Return one bit from the buffer. */
-static inline unsigned bitstream_read_bit(BitstreamContext *bc)
-{
- if (!bc->bits_left)
- refill_64(bc);
-
- return get_val(bc, 1);
-}
-
-/* Return n bits from the buffer. n has to be in the 0-63 range. */
-static inline uint64_t bitstream_read_63(BitstreamContext *bc, unsigned n)
-{
- uint64_t ret = 0;
-#ifdef BITSTREAM_READER_LE
- uint64_t left = 0;
-#endif
-
- if (!n)
- return 0;
-
- if (n > bc->bits_left) {
- n -= bc->bits_left;
-#ifdef BITSTREAM_READER_LE
- left = bc->bits_left;
-#endif
- ret = get_val(bc, bc->bits_left);
- refill_64(bc);
- }
-
-#ifdef BITSTREAM_READER_LE
- ret = get_val(bc, n) << left | ret;
-#else
- ret = get_val(bc, n) | ret << n;
-#endif
-
- return ret;
-}
-
-/* Return n bits from the buffer. n has to be in the 0-32 range. */
-static inline uint32_t bitstream_read(BitstreamContext *bc, unsigned n)
-{
- if (!n)
- return 0;
-
- if (n > bc->bits_left) {
- refill_32(bc);
- if (bc->bits_left < 32)
- bc->bits_left = n;
- }
-
- return get_val(bc, n);
-}
-
-/* Return n bits from the buffer as a signed integer.
- * n has to be in the 0-32 range. */
-static inline int32_t bitstream_read_signed(BitstreamContext *bc, unsigned n)
-{
- return sign_extend(bitstream_read(bc, n), n);
-}
-
-static inline unsigned show_val(const BitstreamContext *bc, unsigned n)
-{
-#ifdef BITSTREAM_READER_LE
- return bc->bits & ((UINT64_C(1) << n) - 1);
-#else
- return bc->bits >> (64 - n);
-#endif
-}
-
-/* Return n bits from the buffer, but do not change the buffer state.
- * n has to be in the 0-32 range. */
-static inline unsigned bitstream_peek(BitstreamContext *bc, unsigned n)
-{
- if (n > bc->bits_left)
- refill_32(bc);
-
- return show_val(bc, n);
-}
-
-/* Return n bits from the buffer as a signed integer, but do not change the
- * buffer state. n has to be in the 0-32 range. */
-static inline int bitstream_peek_signed(BitstreamContext *bc, unsigned n)
-{
- return sign_extend(bitstream_peek(bc, n), n);
-}
-
-static inline void skip_remaining(BitstreamContext *bc, unsigned n)
-{
-#ifdef BITSTREAM_READER_LE
- bc->bits >>= n;
-#else
- bc->bits <<= n;
-#endif
- bc->bits_left -= n;
-}
-
-/* Skip n bits in the buffer. */
-static inline void bitstream_skip(BitstreamContext *bc, unsigned n)
-{
- if (n < bc->bits_left)
- skip_remaining(bc, n);
- else {
- n -= bc->bits_left;
- bc->bits = 0;
- bc->bits_left = 0;
-
- if (n >= 64) {
- unsigned skip = n / 8;
-
- n -= skip * 8;
- bc->ptr += skip;
- }
- refill_64(bc);
- if (n)
- skip_remaining(bc, n);
- }
-}
-
-/* Seek to the given bit position. */
-static inline void bitstream_seek(BitstreamContext *bc, unsigned pos)
-{
- bc->ptr = bc->buffer;
- bc->bits = 0;
- bc->bits_left = 0;
-
- bitstream_skip(bc, pos);
-}
-
-/* Skip bits to a byte boundary. */
-static inline const uint8_t *bitstream_align(BitstreamContext *bc)
-{
- unsigned n = -bitstream_tell(bc) & 7;
- if (n)
- bitstream_skip(bc, n);
- return bc->buffer + (bitstream_tell(bc) >> 3);
-}
-
-/* Read MPEG-1 dc-style VLC (sign bit + mantissa with no MSB).
- * If MSB not set it is negative. */
-static inline int bitstream_read_xbits(BitstreamContext *bc, unsigned length)
-{
- int32_t cache = bitstream_peek(bc, 32);
- int sign = ~cache >> 31;
- skip_remaining(bc, length);
-
- return ((((uint32_t)(sign ^ cache)) >> (32 - length)) ^ sign) - sign;
-}
-
-/* Return decoded truncated unary code for the values 0, 1, 2. */
-static inline int bitstream_decode012(BitstreamContext *bc)
-{
- if (!bitstream_read_bit(bc))
- return 0;
- else
- return bitstream_read_bit(bc) + 1;
-}
-
-/* Return decoded truncated unary code for the values 2, 1, 0. */
-static inline int bitstream_decode210(BitstreamContext *bc)
-{
- if (bitstream_read_bit(bc))
- return 0;
- else
- return 2 - bitstream_read_bit(bc);
-}
-
-/* Read sign bit and flip the sign of the provided value accordingly. */
-static inline int bitstream_apply_sign(BitstreamContext *bc, int val)
-{
- int sign = bitstream_read_signed(bc, 1);
- return (val ^ sign) - sign;
-}
-
-/* Unwind the cache so a refill_32 can fill it again. */
-static inline void bitstream_unwind(BitstreamContext *bc)
-{
- int unwind = 4;
- int unwind_bits = unwind * 8;
-
- if (bc->bits_left < unwind_bits)
- return;
-
- bc->bits >>= unwind_bits;
- bc->bits <<= unwind_bits;
- bc->bits_left -= unwind_bits;
- bc->ptr -= unwind;
-}
-
-/* Unget up to 32 bits. */
-static inline void bitstream_unget(BitstreamContext *bc, uint64_t value,
- size_t amount)
-{
- size_t cache_size = sizeof(bc->bits) * 8;
-
- if (bc->bits_left + amount > cache_size)
- bitstream_unwind(bc);
-
- bc->bits = (bc->bits >> amount) | (value << (cache_size - amount));
- bc->bits_left += amount;
-}
-
-#endif /* AVCODEC_BITSTREAM_H */
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