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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 17:32:43 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 17:32:43 +0000 |
commit | 6bf0a5cb5034a7e684dcc3500e841785237ce2dd (patch) | |
tree | a68f146d7fa01f0134297619fbe7e33db084e0aa /media/ffvpx/libavcodec/put_bits.h | |
parent | Initial commit. (diff) | |
download | thunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.tar.xz thunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.zip |
Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | media/ffvpx/libavcodec/put_bits.h | 428 |
1 files changed, 428 insertions, 0 deletions
diff --git a/media/ffvpx/libavcodec/put_bits.h b/media/ffvpx/libavcodec/put_bits.h new file mode 100644 index 0000000000..4561dc131a --- /dev/null +++ b/media/ffvpx/libavcodec/put_bits.h @@ -0,0 +1,428 @@ +/* + * copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at> + * + * 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 + * bitstream writer API + */ + +#ifndef AVCODEC_PUT_BITS_H +#define AVCODEC_PUT_BITS_H + +#include <stdint.h> +#include <stddef.h> + +#include "config.h" +#include "libavutil/intreadwrite.h" +#include "libavutil/avassert.h" +#include "libavutil/common.h" + +#if ARCH_X86_64 +// TODO: Benchmark and optionally enable on other 64-bit architectures. +typedef uint64_t BitBuf; +#define AV_WBBUF AV_WB64 +#define AV_WLBUF AV_WL64 +#else +typedef uint32_t BitBuf; +#define AV_WBBUF AV_WB32 +#define AV_WLBUF AV_WL32 +#endif + +static const int BUF_BITS = 8 * sizeof(BitBuf); + +typedef struct PutBitContext { + BitBuf bit_buf; + int bit_left; + uint8_t *buf, *buf_ptr, *buf_end; +} PutBitContext; + +/** + * Initialize the PutBitContext s. + * + * @param buffer the buffer where to put bits + * @param buffer_size the size in bytes of buffer + */ +static inline void init_put_bits(PutBitContext *s, uint8_t *buffer, + int buffer_size) +{ + if (buffer_size < 0) { + buffer_size = 0; + buffer = NULL; + } + + s->buf = buffer; + s->buf_end = s->buf + buffer_size; + s->buf_ptr = s->buf; + s->bit_left = BUF_BITS; + s->bit_buf = 0; +} + +/** + * @return the total number of bits written to the bitstream. + */ +static inline int put_bits_count(PutBitContext *s) +{ + return (s->buf_ptr - s->buf) * 8 + BUF_BITS - s->bit_left; +} + +/** + * @return the number of bytes output so far; may only be called + * when the PutBitContext is freshly initialized or flushed. + */ +static inline int put_bytes_output(const PutBitContext *s) +{ + av_assert2(s->bit_left == BUF_BITS); + return s->buf_ptr - s->buf; +} + +/** + * @param round_up When set, the number of bits written so far will be + * rounded up to the next byte. + * @return the number of bytes output so far. + */ +static inline int put_bytes_count(const PutBitContext *s, int round_up) +{ + return s->buf_ptr - s->buf + ((BUF_BITS - s->bit_left + (round_up ? 7 : 0)) >> 3); +} + +/** + * Rebase the bit writer onto a reallocated buffer. + * + * @param buffer the buffer where to put bits + * @param buffer_size the size in bytes of buffer, + * must be large enough to hold everything written so far + */ +static inline void rebase_put_bits(PutBitContext *s, uint8_t *buffer, + int buffer_size) +{ + av_assert0(8*buffer_size >= put_bits_count(s)); + + s->buf_end = buffer + buffer_size; + s->buf_ptr = buffer + (s->buf_ptr - s->buf); + s->buf = buffer; +} + +/** + * @return the number of bits available in the bitstream. + */ +static inline int put_bits_left(PutBitContext* s) +{ + return (s->buf_end - s->buf_ptr) * 8 - BUF_BITS + s->bit_left; +} + +/** + * @param round_up When set, the number of bits written will be + * rounded up to the next byte. + * @return the number of bytes left. + */ +static inline int put_bytes_left(const PutBitContext *s, int round_up) +{ + return s->buf_end - s->buf_ptr - ((BUF_BITS - s->bit_left + (round_up ? 7 : 0)) >> 3); +} + +/** + * Pad the end of the output stream with zeros. + */ +static inline void flush_put_bits(PutBitContext *s) +{ +#ifndef BITSTREAM_WRITER_LE + if (s->bit_left < BUF_BITS) + s->bit_buf <<= s->bit_left; +#endif + while (s->bit_left < BUF_BITS) { + av_assert0(s->buf_ptr < s->buf_end); +#ifdef BITSTREAM_WRITER_LE + *s->buf_ptr++ = s->bit_buf; + s->bit_buf >>= 8; +#else + *s->buf_ptr++ = s->bit_buf >> (BUF_BITS - 8); + s->bit_buf <<= 8; +#endif + s->bit_left += 8; + } + s->bit_left = BUF_BITS; + s->bit_buf = 0; +} + +static inline void flush_put_bits_le(PutBitContext *s) +{ + while (s->bit_left < BUF_BITS) { + av_assert0(s->buf_ptr < s->buf_end); + *s->buf_ptr++ = s->bit_buf; + s->bit_buf >>= 8; + s->bit_left += 8; + } + s->bit_left = BUF_BITS; + s->bit_buf = 0; +} + +#ifdef BITSTREAM_WRITER_LE +#define ff_put_string ff_put_string_unsupported_here +#define ff_copy_bits ff_copy_bits_unsupported_here +#else + +/** + * Put the string string in the bitstream. + * + * @param terminate_string 0-terminates the written string if value is 1 + */ +void ff_put_string(PutBitContext *pb, const char *string, + int terminate_string); + +/** + * Copy the content of src to the bitstream. + * + * @param length the number of bits of src to copy + */ +void ff_copy_bits(PutBitContext *pb, const uint8_t *src, int length); +#endif + +static inline void put_bits_no_assert(PutBitContext *s, int n, BitBuf value) +{ + BitBuf bit_buf; + int bit_left; + + bit_buf = s->bit_buf; + bit_left = s->bit_left; + + /* XXX: optimize */ +#ifdef BITSTREAM_WRITER_LE + bit_buf |= value << (BUF_BITS - bit_left); + if (n >= bit_left) { + if (s->buf_end - s->buf_ptr >= sizeof(BitBuf)) { + AV_WLBUF(s->buf_ptr, bit_buf); + s->buf_ptr += sizeof(BitBuf); + } else { + av_log(NULL, AV_LOG_ERROR, "Internal error, put_bits buffer too small\n"); + av_assert2(0); + } + bit_buf = value >> bit_left; + bit_left += BUF_BITS; + } + bit_left -= n; +#else + if (n < bit_left) { + bit_buf = (bit_buf << n) | value; + bit_left -= n; + } else { + bit_buf <<= bit_left; + bit_buf |= value >> (n - bit_left); + if (s->buf_end - s->buf_ptr >= sizeof(BitBuf)) { + AV_WBBUF(s->buf_ptr, bit_buf); + s->buf_ptr += sizeof(BitBuf); + } else { + av_log(NULL, AV_LOG_ERROR, "Internal error, put_bits buffer too small\n"); + av_assert2(0); + } + bit_left += BUF_BITS - n; + bit_buf = value; + } +#endif + + s->bit_buf = bit_buf; + s->bit_left = bit_left; +} + +/** + * Write up to 31 bits into a bitstream. + * Use put_bits32 to write 32 bits. + */ +static inline void put_bits(PutBitContext *s, int n, BitBuf value) +{ + av_assert2(n <= 31 && value < (1UL << n)); + put_bits_no_assert(s, n, value); +} + +static inline void put_bits_le(PutBitContext *s, int n, BitBuf value) +{ + BitBuf bit_buf; + int bit_left; + + av_assert2(n <= 31 && value < (1UL << n)); + + bit_buf = s->bit_buf; + bit_left = s->bit_left; + + bit_buf |= value << (BUF_BITS - bit_left); + if (n >= bit_left) { + if (s->buf_end - s->buf_ptr >= sizeof(BitBuf)) { + AV_WLBUF(s->buf_ptr, bit_buf); + s->buf_ptr += sizeof(BitBuf); + } else { + av_log(NULL, AV_LOG_ERROR, "Internal error, put_bits buffer too small\n"); + av_assert2(0); + } + bit_buf = value >> bit_left; + bit_left += BUF_BITS; + } + bit_left -= n; + + s->bit_buf = bit_buf; + s->bit_left = bit_left; +} + +static inline void put_sbits(PutBitContext *pb, int n, int32_t value) +{ + av_assert2(n >= 0 && n <= 31); + + put_bits(pb, n, av_mod_uintp2(value, n)); +} + +/** + * Write exactly 32 bits into a bitstream. + */ +static void av_unused put_bits32(PutBitContext *s, uint32_t value) +{ + BitBuf bit_buf; + int bit_left; + + if (BUF_BITS > 32) { + put_bits_no_assert(s, 32, value); + return; + } + + bit_buf = s->bit_buf; + bit_left = s->bit_left; + +#ifdef BITSTREAM_WRITER_LE + bit_buf |= (BitBuf)value << (BUF_BITS - bit_left); + if (s->buf_end - s->buf_ptr >= sizeof(BitBuf)) { + AV_WLBUF(s->buf_ptr, bit_buf); + s->buf_ptr += sizeof(BitBuf); + } else { + av_log(NULL, AV_LOG_ERROR, "Internal error, put_bits buffer too small\n"); + av_assert2(0); + } + bit_buf = (uint64_t)value >> bit_left; +#else + bit_buf = (uint64_t)bit_buf << bit_left; + bit_buf |= (BitBuf)value >> (BUF_BITS - bit_left); + if (s->buf_end - s->buf_ptr >= sizeof(BitBuf)) { + AV_WBBUF(s->buf_ptr, bit_buf); + s->buf_ptr += sizeof(BitBuf); + } else { + av_log(NULL, AV_LOG_ERROR, "Internal error, put_bits buffer too small\n"); + av_assert2(0); + } + bit_buf = value; +#endif + + s->bit_buf = bit_buf; + s->bit_left = bit_left; +} + +/** + * Write up to 64 bits into a bitstream. + */ +static inline void put_bits64(PutBitContext *s, int n, uint64_t value) +{ + av_assert2((n == 64) || (n < 64 && value < (UINT64_C(1) << n))); + + if (n < 32) + put_bits(s, n, value); + else if (n == 32) + put_bits32(s, value); + else if (n < 64) { + uint32_t lo = value & 0xffffffff; + uint32_t hi = value >> 32; +#ifdef BITSTREAM_WRITER_LE + put_bits32(s, lo); + put_bits(s, n - 32, hi); +#else + put_bits(s, n - 32, hi); + put_bits32(s, lo); +#endif + } else { + uint32_t lo = value & 0xffffffff; + uint32_t hi = value >> 32; +#ifdef BITSTREAM_WRITER_LE + put_bits32(s, lo); + put_bits32(s, hi); +#else + put_bits32(s, hi); + put_bits32(s, lo); +#endif + + } +} + +static inline void put_sbits63(PutBitContext *pb, int n, int64_t value) +{ + av_assert2(n >= 0 && n < 64); + + put_bits64(pb, n, (uint64_t)(value) & (~(UINT64_MAX << n))); +} + +/** + * Return the pointer to the byte where the bitstream writer will put + * the next bit. + */ +static inline uint8_t *put_bits_ptr(PutBitContext *s) +{ + return s->buf_ptr; +} + +/** + * Skip the given number of bytes. + * PutBitContext must be flushed & aligned to a byte boundary before calling this. + */ +static inline void skip_put_bytes(PutBitContext *s, int n) +{ + av_assert2((put_bits_count(s) & 7) == 0); + av_assert2(s->bit_left == BUF_BITS); + av_assert0(n <= s->buf_end - s->buf_ptr); + s->buf_ptr += n; +} + +/** + * Skip the given number of bits. + * Must only be used if the actual values in the bitstream do not matter. + * If n is < 0 the behavior is undefined. + */ +static inline void skip_put_bits(PutBitContext *s, int n) +{ + unsigned bits = BUF_BITS - s->bit_left + n; + s->buf_ptr += sizeof(BitBuf) * (bits / BUF_BITS); + s->bit_left = BUF_BITS - (bits & (BUF_BITS - 1)); +} + +/** + * Change the end of the buffer. + * + * @param size the new size in bytes of the buffer where to put bits + */ +static inline void set_put_bits_buffer_size(PutBitContext *s, int size) +{ + av_assert0(size <= INT_MAX/8 - BUF_BITS); + s->buf_end = s->buf + size; +} + +/** + * Pad the bitstream with zeros up to the next byte boundary. + */ +static inline void align_put_bits(PutBitContext *s) +{ + put_bits(s, s->bit_left & 7, 0); +} + +#undef AV_WBBUF +#undef AV_WLBUF + +#endif /* AVCODEC_PUT_BITS_H */ |