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/*
* EVC helper functions for muxers
* Copyright (c) 2022 Dawid Kozinski <d.kozinski@samsung.com>
*
* 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 AVFORMAT_EVC_H
#define AVFORMAT_EVC_H
#include <stdint.h>
#include "libavutil/rational.h"
#include "libavcodec/evc.h"
#include "avio.h"
static inline int evc_get_nalu_type(const uint8_t *bits, int bits_size)
{
int unit_type_plus1 = 0;
if (bits_size >= EVC_NALU_HEADER_SIZE) {
unsigned char *p = (unsigned char *)bits;
// forbidden_zero_bit
if ((p[0] & 0x80) != 0) // Cannot get bitstream information. Malformed bitstream.
return -1;
// nal_unit_type
unit_type_plus1 = (p[0] >> 1) & 0x3F;
}
return unit_type_plus1 - 1;
}
static inline uint32_t evc_read_nal_unit_length(const uint8_t *bits, int bits_size)
{
uint32_t nalu_len = 0;
if (bits_size >= EVC_NALU_LENGTH_PREFIX_SIZE) {
unsigned char *p = (unsigned char *)bits;
for (int i = 0; i < EVC_NALU_LENGTH_PREFIX_SIZE; i++)
nalu_len = (nalu_len << 8) | p[i];
}
return nalu_len;
}
/**
* Writes EVC sample metadata to the provided AVIOContext.
*
* @param pb pointer to the AVIOContext where the evc sample metadata shall be written
* @param buf input data buffer
* @param size size in bytes of the input data buffer
* @param ps_array_completeness @see ISO/IEC 14496-15:2021 Coding of audio-visual objects - Part 15: section 12.3.3.3
*
* @return 0 in case of success, a negative error code in case of failure
*/
int ff_isom_write_evcc(AVIOContext *pb, const uint8_t *data,
int size, int ps_array_completeness);
#endif // AVFORMAT_EVC_H