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diff --git a/media/ffvpx/libavcodec/vlc.h b/media/ffvpx/libavcodec/vlc.h
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+/*
+ * 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
+ */
+
+#ifndef AVCODEC_VLC_H
+#define AVCODEC_VLC_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include "libavutil/macros.h"
+
+#define VLC_MULTI_MAX_SYMBOLS 6
+
+// When changing this, be sure to also update tableprint_vlc.h accordingly.
+typedef int16_t VLCBaseType;
+
+typedef struct VLCElem {
+ VLCBaseType sym, len;
+} VLCElem;
+
+typedef struct VLC {
+ int bits;
+ VLCElem *table;
+ int table_size, table_allocated;
+} VLC;
+
+typedef struct VLC_MULTI_ELEM {
+ uint8_t val[VLC_MULTI_MAX_SYMBOLS];
+ int8_t len; // -31,32
+ uint8_t num;
+} VLC_MULTI_ELEM;
+
+typedef struct VLC_MULTI {
+ VLC_MULTI_ELEM *table;
+ int table_size, table_allocated;
+} VLC_MULTI;
+
+typedef struct RL_VLC_ELEM {
+ int16_t level;
+ int8_t len;
+ uint8_t run;
+} RL_VLC_ELEM;
+
+#define vlc_init(vlc, nb_bits, nb_codes, \
+ bits, bits_wrap, bits_size, \
+ codes, codes_wrap, codes_size, \
+ flags) \
+ ff_vlc_init_sparse(vlc, nb_bits, nb_codes, \
+ bits, bits_wrap, bits_size, \
+ codes, codes_wrap, codes_size, \
+ NULL, 0, 0, flags)
+
+/**
+ * Build VLC decoding tables suitable for use with get_vlc2().
+ *
+ * @param[in,out] vlc The VLC to be initialized; table and table_allocated
+ * must have been set when initializing a static VLC,
+ * otherwise this will be treated as uninitialized.
+ * @param[in] nb_bits The number of bits to use for the VLC table;
+ * higher values take up more memory and cache, but
+ * allow to read codes with fewer reads.
+ * Corresponds to the `bits` parameter of get_vlc2().
+ * @param[in] nb_codes The number of provided bits, codes and (if supplied)
+ * symbol entries.
+ * @param[in] bits The lengths (in bits) of the codes. Entries > 0
+ * correspond to valid codes; entries == 0 will be skipped.
+ * @param[in] bits_wrap Stride (in bytes) of the bits table.
+ * @param[in] codes_size Size of the bits. 1, 2 and 4 are supported.
+ * @param[in] codes Table which gives the bit pattern of of each vlc code.
+ * @param[in] codes_wrap Stride (in bytes) of the codes table.
+ * @param[in] codes_size Size of the codes. 1, 2 and 4 are supported.
+ * @param[in] symbols The symbols, i.e. what is returned from get_vlc2()
+ * when the corresponding code is encountered.
+ * May be NULL, then 0, 1, 2, 3, 4,... will be used.
+ * @param[in] symbols_wrap Stride (in bytes) of the symbols table.
+ * @param[in] symbols_size Size of the symbols. 1 and 2 are supported.
+ * @param[in] flags A combination of the VLC_INIT_* flags.
+ *
+ * 'wrap' and 'size' make it possible to use any memory configuration and types
+ * (byte/word/int) to store the 'bits', 'codes', and 'symbols' tables.
+ */
+int ff_vlc_init_sparse(VLC *vlc, int nb_bits, int nb_codes,
+ const void *bits, int bits_wrap, int bits_size,
+ const void *codes, int codes_wrap, int codes_size,
+ const void *symbols, int symbols_wrap, int symbols_size,
+ int flags);
+
+/**
+ * Build VLC decoding tables suitable for use with get_vlc2()
+ *
+ * This function takes lengths and symbols and calculates the codes from them.
+ * For this the input lengths and symbols have to be sorted according to "left
+ * nodes in the corresponding tree first".
+ *
+ * @param[in,out] vlc The VLC to be initialized; table and table_allocated
+ * must have been set when initializing a static VLC,
+ * otherwise this will be treated as uninitialized.
+ * @param[in] nb_bits The number of bits to use for the VLC table;
+ * higher values take up more memory and cache, but
+ * allow to read codes with fewer reads.
+ * @param[in] nb_codes The number of provided length and (if supplied) symbol
+ * entries.
+ * @param[in] lens The lengths of the codes. Entries > 0 correspond to
+ * valid codes; entries == 0 will be skipped and entries
+ * with len < 0 indicate that the tree is incomplete and
+ * has an open end of length -len at this position.
+ * @param[in] lens_wrap Stride (in bytes) of the lengths.
+ * @param[in] symbols The symbols, i.e. what is returned from get_vlc2()
+ * when the corresponding code is encountered.
+ * May be NULL, then 0, 1, 2, 3, 4,... will be used.
+ * @param[in] symbols_wrap Stride (in bytes) of the symbols.
+ * @param[in] symbols_size Size of the symbols. 1 and 2 are supported.
+ * @param[in] offset An offset to apply to all the valid symbols.
+ * @param[in] flags A combination of the VLC_INIT_* flags; notice that
+ * VLC_INIT_INPUT_LE is pointless and ignored.
+ */
+int ff_vlc_init_from_lengths(VLC *vlc, int nb_bits, int nb_codes,
+ const int8_t *lens, int lens_wrap,
+ const void *symbols, int symbols_wrap, int symbols_size,
+ int offset, int flags, void *logctx);
+
+/**
+ * Build VLC decoding tables suitable for use with get_vlc_multi()
+ *
+ * This function takes lengths and symbols and calculates the codes from them.
+ * For this the input lengths and symbols have to be sorted according to "left
+ * nodes in the corresponding tree first".
+ *
+ * @param[in,out] vlc The VLC to be initialized; table and table_allocated
+ * must have been set when initializing a static VLC,
+ * otherwise this will be treated as uninitialized.
+ * @param[in,out] multi The VLC_MULTI to be initialized; table and table_allocated
+ * must have been set when initializing a static VLC,
+ * otherwise this will be treated as uninitialized.
+ * @param[in] nb_bits The number of bits to use for the VLC table;
+ * higher values take up more memory and cache, but
+ * allow to read codes with fewer reads.
+ * @param[in] nb_elems The max possible number of elements.
+ * @param[in] nb_codes The number of provided length and (if supplied) symbol
+ * entries.
+ * @param[in] lens The lengths of the codes. Entries > 0 correspond to
+ * valid codes; entries == 0 will be skipped and entries
+ * with len < 0 indicate that the tree is incomplete and
+ * has an open end of length -len at this position.
+ * @param[in] lens_wrap Stride (in bytes) of the lengths.
+ * @param[in] symbols The symbols, i.e. what is returned from get_vlc2()
+ * when the corresponding code is encountered.
+ * May be NULL, then 0, 1, 2, 3, 4,... will be used.
+ * @param[in] symbols_wrap Stride (in bytes) of the symbols.
+ * @param[in] symbols_size Size of the symbols. 1 and 2 are supported.
+ * @param[in] offset An offset to apply to all the valid symbols.
+ * @param[in] flags A combination of the VLC_INIT_* flags; notice that
+ * VLC_INIT_INPUT_LE is pointless and ignored.
+ */
+int ff_vlc_init_multi_from_lengths(VLC *vlc, VLC_MULTI *multi, int nb_bits, int nb_elems,
+ int nb_codes, const int8_t *lens, int lens_wrap,
+ const void *symbols, int symbols_wrap, int symbols_size,
+ int offset, int flags, void *logctx);
+
+
+void ff_vlc_free_multi(VLC_MULTI *vlc);
+void ff_vlc_free(VLC *vlc);
+
+#define VLC_INIT_USE_STATIC 1
+#define VLC_INIT_STATIC_OVERLONG (2 | VLC_INIT_USE_STATIC)
+/* If VLC_INIT_INPUT_LE is set, the LSB bit of the codes used to
+ * initialize the VLC table is the first bit to be read. */
+#define VLC_INIT_INPUT_LE 4
+/* If set the VLC is intended for a little endian bitstream reader. */
+#define VLC_INIT_OUTPUT_LE 8
+#define VLC_INIT_LE (VLC_INIT_INPUT_LE | VLC_INIT_OUTPUT_LE)
+
+#define VLC_INIT_CUSTOM_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, \
+ h, i, j, flags, static_size) \
+ do { \
+ static VLCElem table[static_size]; \
+ (vlc)->table = table; \
+ (vlc)->table_allocated = static_size; \
+ ff_vlc_init_sparse(vlc, bits, a, b, c, d, e, f, g, h, i, j, \
+ flags | VLC_INIT_USE_STATIC); \
+ } while (0)
+
+#define VLC_INIT_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, h, i, j, static_size) \
+ VLC_INIT_CUSTOM_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, \
+ h, i, j, 0, static_size)
+
+#define VLC_INIT_LE_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, h, i, j, static_size) \
+ VLC_INIT_CUSTOM_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, \
+ h, i, j, VLC_INIT_LE, static_size)
+
+#define VLC_INIT_CUSTOM_STATIC(vlc, bits, a, b, c, d, e, f, g, flags, static_size) \
+ VLC_INIT_CUSTOM_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, \
+ NULL, 0, 0, flags, static_size)
+
+#define VLC_INIT_STATIC(vlc, bits, a, b, c, d, e, f, g, static_size) \
+ VLC_INIT_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, NULL, 0, 0, static_size)
+
+#define VLC_INIT_LE_STATIC(vlc, bits, a, b, c, d, e, f, g, static_size) \
+ VLC_INIT_LE_SPARSE_STATIC(vlc, bits, a, b, c, d, e, f, g, NULL, 0, 0, static_size)
+
+#define VLC_INIT_STATIC_FROM_LENGTHS(vlc, bits, nb_codes, lens, len_wrap, \
+ symbols, symbols_wrap, symbols_size, \
+ offset, flags, static_size) \
+ do { \
+ static VLCElem table[static_size]; \
+ (vlc)->table = table; \
+ (vlc)->table_allocated = static_size; \
+ ff_vlc_init_from_lengths(vlc, bits, nb_codes, lens, len_wrap, \
+ symbols, symbols_wrap, symbols_size, \
+ offset, flags | VLC_INIT_USE_STATIC, \
+ NULL); \
+ } while (0)
+
+/**
+ * For static VLCs, the number of bits can often be hardcoded
+ * at each get_vlc2() callsite. Then using a full VLC would be uneconomical,
+ * because only VLC.table would ever be accessed after initialization.
+ * The following functions provide wrappers around the relevant ff_vlc_init_*
+ * functions suitable for said task.
+ *
+ * The ff_vlc_init_tables_* functions are intended to be used for initializing
+ * a series of VLCs. The user initializes a VLCInitState with the details
+ * about the underlying array of VLCElem; it is automatically updated by
+ * the ff_vlc_init_tables_* functions (i.e. table is incremented and size
+ * decremented by the number of elements of the current table).
+ * The VLC_INIT_STATIC_OVERLONG flag is also automatically added.
+ * These functions return a pointer to the table just initialized,
+ * potentially to be used in arrays of pointer to VLC tables.
+ *
+ * The ff_vlc_init_table_* functions are intended to be used for initializing
+ * a single VLC table, given by table and table_size. The VLC_INIT_USE_STATIC
+ * flag is automatically added.
+ */
+
+typedef struct VLCInitState {
+ VLCElem *table; ///< points to where the next VLC table will be placed
+ unsigned size; ///< remaining number of elements in table
+} VLCInitState;
+
+#define VLC_INIT_STATE(_table) { .table = (_table), .size = FF_ARRAY_ELEMS(_table) }
+
+void ff_vlc_init_table_from_lengths(VLCElem table[], int table_size,
+ int nb_bits, int nb_codes,
+ const int8_t *lens, int lens_wrap,
+ const void *symbols, int symbols_wrap, int symbols_size,
+ int offset, int flags);
+
+const VLCElem *ff_vlc_init_tables_from_lengths(VLCInitState *state,
+ int nb_bits, int nb_codes,
+ const int8_t *lens, int lens_wrap,
+ const void *symbols, int symbols_wrap, int symbols_size,
+ int offset, int flags);
+
+void ff_vlc_init_table_sparse(VLCElem table[], int table_size,
+ int nb_bits, int nb_codes,
+ const void *bits, int bits_wrap, int bits_size,
+ const void *codes, int codes_wrap, int codes_size,
+ const void *symbols, int symbols_wrap, int symbols_size,
+ int flags);
+
+const VLCElem *ff_vlc_init_tables_sparse(VLCInitState *state,
+ int nb_bits, int nb_codes,
+ const void *bits, int bits_wrap, int bits_size,
+ const void *codes, int codes_wrap, int codes_size,
+ const void *symbols, int symbols_wrap, int symbols_size,
+ int flags);
+
+static inline
+const VLCElem *ff_vlc_init_tables(VLCInitState *state,
+ int nb_bits, int nb_codes,
+ const void *bits, int bits_wrap, int bits_size,
+ const void *codes, int codes_wrap, int codes_size,
+ int flags)
+{
+ return ff_vlc_init_tables_sparse(state, nb_bits, nb_codes,
+ bits, bits_wrap, bits_size,
+ codes, codes_wrap, codes_size,
+ NULL, 0, 0, flags);
+}
+
+#define VLC_INIT_STATIC_SPARSE_TABLE(vlc_table, nb_bits, nb_codes, \
+ bits, bits_wrap, bits_size, \
+ codes, codes_wrap, codes_size, \
+ symbols, symbols_wrap, symbols_size, \
+ flags) \
+ ff_vlc_init_table_sparse(vlc_table, FF_ARRAY_ELEMS(vlc_table), \
+ (nb_bits), (nb_codes), \
+ (bits), (bits_wrap), (bits_size), \
+ (codes), (codes_wrap), (codes_size), \
+ (symbols), (symbols_wrap), (symbols_size), \
+ (flags))
+
+#define VLC_INIT_STATIC_TABLE(vlc_table, nb_bits, nb_codes, \
+ bits, bits_wrap, bits_size, \
+ codes, codes_wrap, codes_size, \
+ flags) \
+ ff_vlc_init_table_sparse(vlc_table, FF_ARRAY_ELEMS(vlc_table), \
+ (nb_bits), (nb_codes), \
+ (bits), (bits_wrap), (bits_size), \
+ (codes), (codes_wrap), (codes_size), \
+ NULL, 0, 0, (flags))
+
+#define VLC_INIT_STATIC_TABLE_FROM_LENGTHS(vlc_table, nb_bits, nb_codes, \
+ lens, lens_wrap, \
+ syms, syms_wrap, syms_size, \
+ offset, flags) \
+ ff_vlc_init_table_from_lengths(vlc_table, FF_ARRAY_ELEMS(vlc_table), \
+ (nb_bits), (nb_codes), \
+ (lens), (lens_wrap), \
+ (syms), (syms_wrap), (syms_size), \
+ (offset), (flags))
+
+#endif /* AVCODEC_VLC_H */
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