[FFmpeg-devel] [PATCH 2/2] Provided support for MPEG-5 EVC (Essential Video Coding) codec
Dawid Kozinski
d.kozinski at samsung.com
Thu Aug 11 15:36:47 EEST 2022
- Added muxer for EVC format (MP4, raw)
- Added demuxer for EVC format (MP4)
- Added evc extension to the list of extensions for ff_mov_demuxer
- Added information to moov atom
Signed-off-by: Dawid Kozinski <d.kozinski at samsung.com>
---
libavformat/evc.c | 461 +++++++++++++++++++++++++++++++++++++++++++
libavformat/evc.h | 147 ++++++++++++++
libavformat/evcdec.c | 142 +++++++++++++
3 files changed, 750 insertions(+)
create mode 100644 libavformat/evc.c
create mode 100644 libavformat/evc.h
create mode 100644 libavformat/evcdec.c
diff --git a/libavformat/evc.c b/libavformat/evc.c
new file mode 100644
index 0000000000..9297fa5d5c
--- /dev/null
+++ b/libavformat/evc.c
@@ -0,0 +1,461 @@
+/*
+ * EVC helper functions for muxers
+ * Copyright (c) 2022 Dawid Kozinski <d.kozinski at 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
+ */
+
+#include "libavutil/intreadwrite.h"
+#include "libavcodec/get_bits.h"
+#include "libavcodec/golomb.h"
+#include "avformat.h"
+#include "avio.h"
+#include "evc.h"
+#include "avio_internal.h"
+
+// The length field that indicates the length in bytes of the following NAL unit is configured to be of 4 bytes
+#define EVC_NAL_UNIT_LENGTH_BYTE (4) /* byte */
+#define EVC_NAL_HEADER_SIZE (2) /* byte */
+
+// rpl structure
+typedef struct RefPicListStruct {
+ int poc;
+ int tid;
+ int ref_pic_num;
+ int ref_pic_active_num;
+ int ref_pics[EVC_MAX_NUM_REF_PICS];
+ char pic_type;
+
+} RefPicListStruct;
+
+// The sturcture reflects SPS RBSP(raw byte sequence payload) layout
+// @see ISO_IEC_23094-1 section 7.3.2.1
+//
+// The following descriptors specify the parsing process of each element
+// u(n) - unsigned integer using n bits
+// ue(v) - unsigned integer 0-th order Exp_Golomb-coded syntax element with the left bit first
+typedef struct EVCSPS {
+ int sps_seq_parameter_set_id; // ue(v)
+ int profile_idc; // u(8)
+ int level_idc; // u(8)
+ int toolset_idc_h; // u(32)
+ int toolset_idc_l; // u(32)
+ int chroma_format_idc; // ue(v)
+ int pic_width_in_luma_samples; // ue(v)
+ int pic_height_in_luma_samples; // ue(v)
+ int bit_depth_luma_minus8; // ue(v)
+ int bit_depth_chroma_minus8; // ue(v)
+
+ // @note
+ // Currently the structure does not reflect the entire SPS RBSP layout.
+ // It contains only the fields that are necessary to read from the NAL unit all the values
+ // necessary for the correct initialization of EVCDecoderConfigurationRecord
+
+ // @note
+ // If necessary, add the missing fields to the structure to reflect
+ // the contents of the entire NAL unit of the SPS type
+
+} EVCSPS;
+
+typedef struct EVCNALUnitArray {
+ uint8_t array_completeness;
+ uint8_t NAL_unit_type;
+ uint16_t numNalus;
+ uint16_t *nalUnitLength;
+ uint8_t **nalUnit;
+} EVCNALUnitArray;
+
+/**
+ * @brief Specifies the decoder configuration information for ISO/IEC 23094-1 video content.
+ * @see ISO/IEC 14496-15:2021 Coding of audio-visual objects — Part 15:
+ * Carriage of network abstraction layer (NAL) unit structured video in the ISO base media file format
+ */
+typedef struct EVCDecoderConfigurationRecord {
+ uint8_t configurationVersion; // 8 bits
+ uint8_t profile_idc; // 8 bits
+ uint8_t level_idc; // 8 bits
+ uint32_t toolset_idc_h; // 32 bits
+ uint32_t toolset_idc_l; // 32 bits
+ uint8_t chroma_format_idc; // 2 bits
+ uint8_t bit_depth_luma_minus8; // 3 bits
+ uint8_t bit_depth_chroma_minus8; // 3 bits
+ uint16_t pic_width_in_luma_samples; // 16 bits
+ uint16_t pic_height_in_luma_samples; // 16 bits
+ uint8_t reserved; // 6 bits '000000'b
+ uint8_t lengthSizeMinusOne; // 2 bits
+ uint8_t num_of_arrays; // 8 bits
+ EVCNALUnitArray *array;
+} EVCDecoderConfigurationRecord;
+
+typedef struct NALU {
+ int offset;
+ uint32_t size;
+} NALU;
+
+typedef struct NALUList {
+ NALU *nalus;
+ unsigned nalus_array_size;
+ unsigned nb_nalus; ///< valid entries in nalus
+} NALUList;
+
+static int get_nalu_type(const uint8_t *bits, int bits_size)
+{
+ int unit_type_plus1 = 0;
+
+ if (bits_size >= EVC_NAL_HEADER_SIZE) {
+ unsigned char *p = (unsigned char *)bits;
+ // forbidden_zero_bit
+ if ((p[0] & 0x80) != 0)
+ return -1;
+
+ // nal_unit_type
+ unit_type_plus1 = (p[0] >> 1) & 0x3F;
+ }
+
+ return unit_type_plus1 - 1;
+}
+
+static uint32_t read_nal_unit_length(const uint8_t *bits, int bits_size)
+{
+ uint32_t nalu_len = 0;
+
+ if (bits_size >= EVC_NAL_UNIT_LENGTH_BYTE) {
+
+ int t = 0;
+ unsigned char *p = (unsigned char *)bits;
+
+ for (int i = 0; i < EVC_NAL_UNIT_LENGTH_BYTE; i++)
+ t = (t << 8) | p[i];
+
+ nalu_len = t;
+ if (nalu_len == 0)
+ return 0;
+ }
+
+ return nalu_len;
+}
+
+// @see ISO_IEC_23094-1 (7.3.2.1 SPS RBSP syntax)
+static int evcc_parse_sps(const uint8_t *bs, int bs_size, EVCDecoderConfigurationRecord *evcc)
+{
+ GetBitContext gb;
+ int sps_seq_parameter_set_id;
+ EVCSPS sps;
+
+ if (init_get_bits8(&gb, bs, bs_size) < 0)
+ return 0;
+
+ sps.sps_seq_parameter_set_id = get_ue_golomb(&gb);
+
+ if (sps_seq_parameter_set_id >= EVC_MAX_SPS_COUNT)
+ return 0;
+
+ // the Baseline profile is indicated by profile_idc eqal to 0
+ // the Main profile is indicated by profile_idc eqal to 1
+ sps.profile_idc = get_bits(&gb, 8);
+
+ sps.level_idc = get_bits(&gb, 8);
+
+ sps.toolset_idc_h = get_bits(&gb, 32);
+ sps.toolset_idc_l = get_bits(&gb, 32);
+
+ // 0 - monochrome
+ // 1 - 4:2:0
+ // 2 - 4:2:2
+ // 3 - 4:4:4
+ sps.chroma_format_idc = get_ue_golomb(&gb);
+
+ sps.pic_width_in_luma_samples = get_ue_golomb(&gb);
+ sps.pic_height_in_luma_samples = get_ue_golomb(&gb);
+
+ sps.bit_depth_luma_minus8 = get_ue_golomb(&gb);
+ sps.bit_depth_chroma_minus8 = get_ue_golomb(&gb);
+
+ evcc->profile_idc = sps.profile_idc;
+ evcc->level_idc = sps.level_idc;
+ evcc->toolset_idc_h = sps.toolset_idc_h;
+ evcc->toolset_idc_l = sps.toolset_idc_l;
+ evcc->chroma_format_idc = sps.chroma_format_idc;
+ evcc->bit_depth_luma_minus8 = sps.bit_depth_luma_minus8;
+ evcc->bit_depth_chroma_minus8 = sps.bit_depth_chroma_minus8;
+ evcc->pic_width_in_luma_samples = sps.pic_width_in_luma_samples;
+ evcc->pic_height_in_luma_samples = sps.pic_height_in_luma_samples;
+
+ return 0;
+}
+
+static int evcc_array_add_nal_unit(uint8_t *nal_buf, uint32_t nal_size,
+ uint8_t nal_type, int ps_array_completeness,
+ EVCDecoderConfigurationRecord *evcc)
+{
+ int ret;
+ uint8_t index;
+ uint16_t numNalus;
+ EVCNALUnitArray *array;
+
+ for (index = 0; index < evcc->num_of_arrays; index++)
+ if (evcc->array[index].NAL_unit_type == nal_type)
+ break;
+
+ if (index >= evcc->num_of_arrays) {
+ uint8_t i;
+
+ ret = av_reallocp_array(&evcc->array, index + 1, sizeof(EVCNALUnitArray));
+ if (ret < 0)
+ return ret;
+
+ for (i = evcc->num_of_arrays; i <= index; i++)
+ memset(&evcc->array[i], 0, sizeof(EVCNALUnitArray));
+ evcc->num_of_arrays = index + 1;
+ }
+
+ array = &evcc->array[index];
+ numNalus = array->numNalus;
+
+ ret = av_reallocp_array(&array->nalUnit, numNalus + 1, sizeof(uint8_t *));
+ if (ret < 0)
+ return ret;
+
+ ret = av_reallocp_array(&array->nalUnitLength, numNalus + 1, sizeof(uint16_t));
+ if (ret < 0)
+ return ret;
+
+ array->nalUnit [numNalus] = nal_buf;
+ array->nalUnitLength[numNalus] = nal_size;
+ array->NAL_unit_type = nal_type;
+ array->numNalus++;
+
+ /*
+ * When the sample entry name is 'evc1', the default and mandatory value of
+ * array_completeness is 1 for arrays of all types of parameter sets, and 0
+ * for all other arrays.
+ */
+ if (nal_type == EVC_SPS_NUT || nal_type == EVC_PPS_NUT)
+ array->array_completeness = ps_array_completeness;
+
+ return 0;
+}
+
+static void evcc_init(EVCDecoderConfigurationRecord *evcc)
+{
+ memset(evcc, 0, sizeof(EVCDecoderConfigurationRecord));
+ evcc->configurationVersion = 1;
+ evcc->lengthSizeMinusOne = 3; // 4 bytes
+}
+
+static void evcc_close(EVCDecoderConfigurationRecord *evcc)
+{
+ uint8_t i;
+
+ for (i = 0; i < evcc->num_of_arrays; i++) {
+ evcc->array[i].numNalus = 0;
+ av_freep(&evcc->array[i].nalUnit);
+ av_freep(&evcc->array[i].nalUnitLength);
+ }
+
+ evcc->num_of_arrays = 0;
+ av_freep(&evcc->array);
+}
+
+static int evcc_write(AVIOContext *pb, EVCDecoderConfigurationRecord *evcc)
+{
+ uint8_t i;
+ uint16_t j, aps_count = 0, sps_count = 0, pps_count = 0;
+
+ av_log(NULL, AV_LOG_TRACE, "configurationVersion: %"PRIu8"\n",
+ evcc->configurationVersion);
+ av_log(NULL, AV_LOG_TRACE, "profile_idc: %"PRIu8"\n",
+ evcc->profile_idc);
+ av_log(NULL, AV_LOG_TRACE, "level_idc: %"PRIu8"\n",
+ evcc->level_idc);
+ av_log(NULL, AV_LOG_TRACE, "toolset_idc_h: %"PRIu32"\n",
+ evcc->toolset_idc_h);
+ av_log(NULL, AV_LOG_TRACE, "toolset_idc_l: %"PRIu32"\n",
+ evcc->toolset_idc_l);
+ av_log(NULL, AV_LOG_TRACE, "chroma_format_idc: %"PRIu8"\n",
+ evcc->chroma_format_idc);
+ av_log(NULL, AV_LOG_TRACE, "bit_depth_luma_minus8: %"PRIu8"\n",
+ evcc->bit_depth_luma_minus8);
+ av_log(NULL, AV_LOG_TRACE, "bit_depth_chroma_minus8: %"PRIu8"\n",
+ evcc->bit_depth_chroma_minus8);
+ av_log(NULL, AV_LOG_TRACE, "pic_width_in_luma_samples: %"PRIu16"\n",
+ evcc->pic_width_in_luma_samples);
+ av_log(NULL, AV_LOG_TRACE, "pic_height_in_luma_samples: %"PRIu16"\n",
+ evcc->pic_height_in_luma_samples);
+ av_log(NULL, AV_LOG_TRACE, "lengthSizeMinusOne: %"PRIu8"\n",
+ evcc->lengthSizeMinusOne);
+ av_log(NULL, AV_LOG_TRACE, "num_of_arrays: %"PRIu8"\n",
+ evcc->num_of_arrays);
+ for (i = 0; i < evcc->num_of_arrays; i++) {
+ av_log(NULL, AV_LOG_TRACE, "array_completeness[%"PRIu8"]: %"PRIu8"\n",
+ i, evcc->array[i].array_completeness);
+ av_log(NULL, AV_LOG_TRACE, "NAL_unit_type[%"PRIu8"]: %"PRIu8"\n",
+ i, evcc->array[i].NAL_unit_type);
+ av_log(NULL, AV_LOG_TRACE, "numNalus[%"PRIu8"]: %"PRIu16"\n",
+ i, evcc->array[i].numNalus);
+ for (j = 0; j < evcc->array[i].numNalus; j++)
+ av_log(NULL, AV_LOG_TRACE,
+ "nalUnitLength[%"PRIu8"][%"PRIu16"]: %"PRIu16"\n",
+ i, j, evcc->array[i].nalUnitLength[j]);
+ }
+
+ /*
+ * We need at least one SPS.
+ */
+ for (i = 0; i < evcc->num_of_arrays; i++)
+ switch (evcc->array[i].NAL_unit_type) {
+ case EVC_APS_NUT:
+ aps_count += evcc->array[i].numNalus;
+ break;
+ case EVC_SPS_NUT:
+ sps_count += evcc->array[i].numNalus;
+ break;
+ case EVC_PPS_NUT:
+ pps_count += evcc->array[i].numNalus;
+ break;
+ default:
+ break;
+ }
+ if (!sps_count || sps_count > EVC_MAX_SPS_COUNT)
+ return AVERROR_INVALIDDATA;
+
+ /* unsigned int(8) configurationVersion = 1; */
+ avio_w8(pb, evcc->configurationVersion);
+
+ /* unsigned int(8) profile_idc */
+ avio_w8(pb, evcc->profile_idc);
+
+ /* unsigned int(8) profile_idc */
+ avio_w8(pb, evcc->level_idc);
+
+ /* unsigned int(32) toolset_idc_h */
+ avio_wb32(pb, evcc->toolset_idc_h);
+
+ /* unsigned int(32) toolset_idc_l */
+ avio_wb32(pb, evcc->toolset_idc_l);
+
+ /*
+ * unsigned int(2) chroma_format_idc;
+ * unsigned int(3) bit_depth_luma_minus8;
+ * unsigned int(3) bit_depth_chroma_minus8;
+ */
+ avio_w8(pb, evcc->chroma_format_idc << 6 |
+ evcc->bit_depth_luma_minus8 << 3 |
+ evcc->bit_depth_chroma_minus8);
+
+ /* unsigned int(16) pic_width_in_luma_samples; */
+ avio_wb16(pb, evcc->pic_width_in_luma_samples);
+
+ /* unsigned int(16) pic_width_in_luma_samples; */
+ avio_wb16(pb, evcc->pic_height_in_luma_samples);
+
+ /*
+ * bit(6) reserved = '111111'b;
+ * unsigned int(2) chromaFormat;
+ */
+ avio_w8(pb, evcc->lengthSizeMinusOne | 0xfc);
+
+ /* unsigned int(8) numOfArrays; */
+ avio_w8(pb, evcc->num_of_arrays);
+
+ for (i = 0; i < evcc->num_of_arrays; i++) {
+ /*
+ * bit(1) array_completeness;
+ * unsigned int(1) reserved = 0;
+ * unsigned int(6) NAL_unit_type;
+ */
+ avio_w8(pb, evcc->array[i].array_completeness << 7 |
+ evcc->array[i].NAL_unit_type & 0x3f);
+
+ /* unsigned int(16) numNalus; */
+ avio_wb16(pb, evcc->array[i].numNalus);
+
+ for (j = 0; j < evcc->array[i].numNalus; j++) {
+ /* unsigned int(16) nalUnitLength; */
+ avio_wb16(pb, evcc->array[i].nalUnitLength[j]);
+
+ /* bit(8*nalUnitLength) nalUnit; */
+ avio_write(pb, evcc->array[i].nalUnit[j],
+ evcc->array[i].nalUnitLength[j]);
+ }
+ }
+
+ return 0;
+}
+
+int ff_isom_write_evcc(AVIOContext *pb, const uint8_t *data,
+ int size, int ps_array_completeness)
+{
+ EVCDecoderConfigurationRecord evcc;
+ int ret = 0;
+
+ if (size < 8) {
+ /* We can't write a valid evcC from the provided data */
+ return AVERROR_INVALIDDATA;
+ } else if (*data == 1) {
+ /* Data is already evcC-formatted */
+ avio_write(pb, data, size);
+ return 0;
+ }
+
+ evcc_init(&evcc);
+
+ int nalu_type;
+ size_t nalu_size;
+ unsigned char *bits = (unsigned char *)data;
+ int bytes_to_read = size;
+
+ while (bytes_to_read > EVC_NAL_UNIT_LENGTH_BYTE) {
+
+ nalu_size = read_nal_unit_length(bits, EVC_NAL_UNIT_LENGTH_BYTE);
+ if (nalu_size == 0) break;
+
+ bits += EVC_NAL_UNIT_LENGTH_BYTE;
+ bytes_to_read -= EVC_NAL_UNIT_LENGTH_BYTE;
+
+ if (bytes_to_read < nalu_size) break;
+
+ nalu_type = get_nalu_type(bits, bytes_to_read);
+ uint8_t *nalu_buf = bits;
+
+ switch (nalu_type) {
+ case EVC_APS_NUT:
+ case EVC_SPS_NUT:
+ case EVC_PPS_NUT:
+ ret = evcc_array_add_nal_unit(nalu_buf, nalu_size, nalu_type, ps_array_completeness, &evcc);
+ if (ret < 0)
+ goto end;
+ else if (nalu_type == EVC_SPS_NUT)
+ ret = evcc_parse_sps(nalu_buf, nalu_size, &evcc);
+ if (ret < 0)
+ goto end;
+ break;
+ default:
+ break;
+ }
+
+ bits += nalu_size;
+ bytes_to_read -= nalu_size;
+ }
+
+ ret = evcc_write(pb, &evcc);
+
+end:
+ evcc_close(&evcc);
+ return ret;
+}
+
diff --git a/libavformat/evc.h b/libavformat/evc.h
new file mode 100644
index 0000000000..d7b93d521d
--- /dev/null
+++ b/libavformat/evc.h
@@ -0,0 +1,147 @@
+/*
+ * EVC helper functions for muxers
+ * Copyright (c) 2022 Dawid Kozinski <d.kozinski at 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 "avio.h"
+
+/**
+ * @see ISO_IEC_23094-1_2020, 7.4.2.2 NAL unit header semantic
+ * Table 4 – NAL unit type codes and NAL unit type classes
+ */
+enum EVCNALUnitType {
+ EVC_NOIDR_NUT = 0,
+ EVC_IDR_NUT = 1,
+ EVC_RSV_VCL_NUT02 = 2,
+ EVC_RSV_VCL_NUT03 = 3,
+ EVC_RSV_VCL_NUT04 = 4,
+ EVC_RSV_VCL_NUT05 = 5,
+ EVC_RSV_VCL_NUT06 = 6,
+ EVC_RSV_VCL_NUT07 = 7,
+ EVC_RSV_VCL_NUT08 = 8,
+ EVC_RSV_VCL_NUT09 = 9,
+ EVC_RSV_VCL_NUT10 = 10,
+ EVC_RSV_VCL_NUT11 = 11,
+ EVC_RSV_VCL_NUT12 = 12,
+ EVC_RSV_VCL_NUT13 = 13,
+ EVC_RSV_VCL_NUT14 = 14,
+ EVC_RSV_VCL_NUT15 = 15,
+ EVC_RSV_VCL_NUT16 = 16,
+ EVC_RSV_VCL_NUT17 = 17,
+ EVC_RSV_VCL_NUT18 = 18,
+ EVC_RSV_VCL_NUT19 = 19,
+ EVC_RSV_VCL_NUT20 = 20,
+ EVC_RSV_VCL_NUT21 = 21,
+ EVC_RSV_VCL_NUT22 = 22,
+ EVC_RSV_VCL_NUT23 = 23,
+ EVC_SPS_NUT = 24,
+ EVC_PPS_NUT = 25,
+ EVC_APS_NUT = 26,
+ EVC_FD_NUT = 27,
+ EVC_SEI_NUT = 28,
+ EVC_RSV_NONVCL29 = 29,
+ EVC_RSV_NONVCL30 = 30,
+ EVC_RSV_NONVCL31 = 31,
+ EVC_RSV_NONVCL32 = 32,
+ EVC_RSV_NONVCL33 = 33,
+ EVC_RSV_NONVCL34 = 34,
+ EVC_RSV_NONVCL35 = 35,
+ EVC_RSV_NONVCL36 = 36,
+ EVC_RSV_NONVCL37 = 37,
+ EVC_RSV_NONVCL38 = 38,
+ EVC_RSV_NONVCL39 = 39,
+ EVC_RSV_NONVCL40 = 40,
+ EVC_RSV_NONVCL41 = 41,
+ EVC_RSV_NONVCL42 = 42,
+ EVC_RSV_NONVCL43 = 43,
+ EVC_RSV_NONVCL44 = 44,
+ EVC_RSV_NONVCL45 = 45,
+ EVC_RSV_NONVCL46 = 46,
+ EVC_RSV_NONVCL47 = 47,
+ EVC_RSV_NONVCL48 = 48,
+ EVC_RSV_NONVCL49 = 49,
+ EVC_RSV_NONVCL50 = 50,
+ EVC_RSV_NONVCL51 = 51,
+ EVC_RSV_NONVCL52 = 52,
+ EVC_RSV_NONVCL53 = 53,
+ EVC_RSV_NONVCL54 = 54,
+ EVC_RSV_NONVCL55 = 55,
+ EVC_UNSPEC_NUT56 = 56,
+ EVC_UNSPEC_NUT57 = 57,
+ EVC_UNSPEC_NUT58 = 58,
+ EVC_UNSPEC_NUT59 = 59,
+ EVC_UNSPEC_NUT60 = 60,
+ EVC_UNSPEC_NUT61 = 61,
+ EVC_UNSPEC_NUT62 = 62
+};
+
+enum {
+ // 7.4.3.2: aps_video_parameter_set_id is u(4).
+ EVC_MAX_APS_COUNT = 32,
+
+ // 7.4.3.1: sps_seq_parameter_set_id is in [0, 15].
+ EVC_MAX_SPS_COUNT = 16,
+
+ // 7.4.3.2: pps_pic_parameter_set_id is in [0, 63].
+ EVC_MAX_PPS_COUNT = 64,
+
+ // 7.4.5: slice header slice_pic_parameter_set_id in [0, 63]
+ EVC_MAX_SH_COUNT = 64,
+
+ // E.3.2: cpb_cnt_minus1[i] is in [0, 31].
+ EVC_MAX_CPB_CNT = 32,
+
+ // A.4.1: in table A.1 the highest level allows a MaxLumaPs of 35 651 584.
+ EVC_MAX_LUMA_PS = 35651584,
+
+ EVC_MAX_NUM_REF_PICS = 21,
+
+ // A.4.1: pic_width_in_luma_samples and pic_height_in_luma_samples are
+ // constrained to be not greater than sqrt(MaxLumaPs * 8). Hence height/
+ // width are bounded above by sqrt(8 * 35651584) = 16888.2 samples.
+ EVC_MAX_WIDTH = 16888,
+ EVC_MAX_HEIGHT = 16888,
+
+ // A.4.1: table A.1 allows at most 22 tile rows for any level.
+ EVC_MAX_TILE_ROWS = 22,
+ // A.4.1: table A.1 allows at most 20 tile columns for any level.
+ EVC_MAX_TILE_COLUMNS = 20,
+
+ // A.4.1: table A.1 allows at most 600 slice segments for any level.
+ EVC_MAX_SLICE_SEGMENTS = 600,
+
+ // 7.4.7.1: in the worst case (tiles_enabled_flag and
+ // entropy_coding_sync_enabled_flag are both set), entry points can be
+ // placed at the beginning of every Ctb row in every tile, giving an
+ // upper bound of (num_tile_columns_minus1 + 1) * PicHeightInCtbsY - 1.
+ // Only a stream with very high resolution and perverse parameters could
+ // get near that, though, so set a lower limit here with the maximum
+ // possible value for 4K video (at most 135 16x16 Ctb rows).
+ HEVC_MAX_ENTRY_POINT_OFFSETS = EVC_MAX_TILE_COLUMNS * 135,
+};
+
+int ff_isom_write_evcc(AVIOContext *pb, const uint8_t *data,
+ int size, int ps_array_completeness);
+
+#endif // AVFORMAT_EVC_H
\ No newline at end of file
diff --git a/libavformat/evcdec.c b/libavformat/evcdec.c
new file mode 100644
index 0000000000..58dc671d24
--- /dev/null
+++ b/libavformat/evcdec.c
@@ -0,0 +1,142 @@
+/*
+ * RAW EVC video demuxer
+ *
+ * Copyright (c) 2021 Dawid Kozinski <d.kozinski at 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
+ */
+
+#include "libavcodec/get_bits.h"
+#include "libavcodec/golomb.h"
+#include "libavcodec/internal.h"
+
+#include "rawdec.h"
+#include "avformat.h"
+
+// The length field that indicates the length in bytes of the following NAL unit is configured to be of 4 bytes
+#define EVC_NAL_UNIT_LENGTH_BYTE (4) /* byte */
+
+#define EVC_NAL_HEADER_SIZE (2) /* byte */
+#define MAX_SPS_CNT (16) /* defined value in EVC standard */
+
+// NALU types
+// @see ISO_IEC_23094-1_2020 7.4.2.2 NAL unit header semantics
+//
+#define EVC_NUT_NONIDR (0) /* Coded slice of a non-IDR picture */
+#define EVC_NUT_IDR (1) /* Coded slice of an IDR picture */
+#define EVC_NUT_SPS (24) /* Sequence parameter set */
+#define EVC_NUT_PPS (25) /* Picture paremeter set */
+#define EVC_NUT_APS (26) /* Adaptation parameter set */
+#define EVC_NUT_FD (27) /* Filler data */
+#define EVC_NUT_SEI (28) /* Supplemental enhancement information */
+
+typedef struct EVCParserContext {
+ int got_sps;
+ int got_pps;
+ int got_idr;
+ int got_nonidr;
+} EVCParserContext;
+
+static int get_nalu_type(const uint8_t *bits, int bits_size)
+{
+ int unit_type_plus1 = 0;
+
+ if(bits_size >= EVC_NAL_HEADER_SIZE) {
+ unsigned char *p = (unsigned char *)bits;
+ // forbidden_zero_bit
+ if ((p[0] & 0x80) != 0) {
+ av_log(NULL, AV_LOG_ERROR, "Cannot get bitstream information. Malformed bitstream.\n");
+ return -1;
+ }
+
+ // nal_unit_type
+ unit_type_plus1 = (p[0] >> 1) & 0x3F;
+ }
+
+ return unit_type_plus1 - 1;
+}
+
+static uint32_t read_nal_unit_length(const uint8_t *bits, int bits_size)
+{
+ uint32_t nalu_len = 0;
+
+ if(bits_size >= EVC_NAL_UNIT_LENGTH_BYTE) {
+
+ int t = 0;
+ unsigned char *p = (unsigned char *)bits;
+
+ for(int i=0; i<EVC_NAL_UNIT_LENGTH_BYTE; i++) {
+ t = (t << 8) | p[i];
+ }
+
+ nalu_len = t;
+ if(nalu_len == 0) {
+ av_log(NULL, AV_LOG_ERROR, "Invalid bitstream size!\n");
+ return 0;
+ }
+ }
+
+ return nalu_len;
+}
+
+static int parse_nal_units(const AVProbeData *p, EVCParserContext *ev)
+{
+ int nalu_type;
+ size_t nalu_size;
+ unsigned char *bits = (unsigned char *)p->buf;
+ int bytes_to_read = p->buf_size;
+
+ while(bytes_to_read > EVC_NAL_UNIT_LENGTH_BYTE) {
+
+ nalu_size = read_nal_unit_length(bits, EVC_NAL_UNIT_LENGTH_BYTE);
+ if(nalu_size == 0) break;
+
+ bits += EVC_NAL_UNIT_LENGTH_BYTE;
+ bytes_to_read -= EVC_NAL_UNIT_LENGTH_BYTE;
+
+ if(bytes_to_read < nalu_size) break;
+
+ nalu_type = get_nalu_type(bits, bytes_to_read);
+
+ bits += nalu_size;
+ bytes_to_read -= nalu_size;
+
+ if (nalu_type == EVC_NUT_SPS)
+ ev->got_sps++;
+ else if (nalu_type == EVC_NUT_PPS)
+ ev->got_pps++;
+ else if (nalu_type == EVC_NUT_IDR )
+ ev->got_idr++;
+ else if (nalu_type == EVC_NUT_NONIDR)
+ ev->got_nonidr++;
+ }
+
+ return 0;
+}
+
+static int evc_probe(const AVProbeData *p)
+{
+ EVCParserContext ev = {0};
+ int ret = parse_nal_units(p, &ev);
+
+ if (ret == 0 && ev.got_sps && ev.got_pps && (ev.got_idr || ev.got_nonidr > 3))
+ return AVPROBE_SCORE_EXTENSION + 1; // 1 more than .mpg
+
+ return 0;
+}
+
+FF_DEF_RAWVIDEO_DEMUXER(evc, "raw EVC video", evc_probe, "evc", AV_CODEC_ID_EVC)
--
2.17.1
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