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-rw-r--r--media/ffvpx/libavcodec/put_bits.h421
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diff --git a/media/ffvpx/libavcodec/put_bits.h b/media/ffvpx/libavcodec/put_bits.h
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+/*
+ * 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
+
+ }
+}
+
+/**
+ * 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 */
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