/* * EVC helper functions for muxers * Copyright (c) 2022 Dawid Kozinski * * 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 #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