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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
* iso11172-1.h
*
* Wed Aug 31 13:48:30 CEST 2005
* Copyright 2005 Bent Bisballe Nyeng
* deva@aasimon.org
****************************************************************************/
/*
* This file is part of MIaV.
*
* MIaV is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* MIaV 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with MIaV; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/
/*
* This file contains symbols used to create an ISO11172-1 compatible multiplexed
* MPEG stream.
*/
#ifndef __MIAV_ISO11172_1_H__
#define __MIAV_ISO11172_1_H__
#include <stdint.h>
#define CLOCK_90KHZ 90000
namespace ISO11172_1 {
////////////////////////////////////////////////////
// Types
////////////////////////////////////////////////////
// 64 bits (8 bytes)
typedef union {
struct {
uint64_t marker_bit3:1;
uint64_t system_clock_reference3:15;
uint64_t marker_bit2:1;
uint64_t system_clock_reference2:15;
uint64_t marker_bit1:1;
uint64_t system_clock_reference1:3;
uint64_t padding:4;
uint64_t stuffing_byte:8;
uint64_t packet_length:16;
} bits;
uint64_t ulli;
} packet_header;
#define MASK3 0x7
#define MASK15 0x7FFF
#define TIMECODE32_30(x) ((x >> 30) & MASK3 )
#define TIMECODE29_15(x) ((x >> 15) & MASK15)
#define TIMECODE14_0(x) ((x >> 0) & MASK15)
typedef union { // <============ you are here...
struct {
uint64_t marker_bit5:1;
uint64_t mux_rate:22;
uint64_t marker_bit4:1;
uint64_t marker_bit3:1;
uint64_t system_clock_reference3:15;
uint64_t marker_bit2:1;
uint64_t system_clock_reference2:15;
uint64_t marker_bit1:1;
uint64_t system_clock_reference1:3;
uint64_t padding:4;
} bits;
uint64_t ulli;
} pack_header;
typedef union {
struct {
uint32_t reserved_byte:8;
uint32_t video_bound:5;
uint32_t marker_bit:1;
uint32_t system_video_clock_flag:1;
uint32_t system_audio_clock_flag:1;
uint32_t CSPS_flag:1;
uint32_t fixed_flag:1;
uint32_t audio_bound:6;
} bits;
uint32_t ulli;
} system_header;
typedef union {
struct {
uint32_t STD_buffer_size_bound:13;
uint32_t STD_buffer_bound_scale:1;
uint32_t market_bits:2;
uint32_t stream_id:8;
} bits;
uint32_t uli;
} stream_description;
////////////////////////////////////////////////////
// Constants
////////////////////////////////////////////////////
const char pack_start_code[] = "\x00\x00\x01\xBA";
const char system_header_start_code[] = "\x00\x00\x01\xBB";
const char packet_start_code_prefix[] = "\x00\x00\x01";
const char stream_id_video1[] = "\xE3";
const char stream_id_video2[] = "\xE4";
const char stream_id_video3[] = "\xE5";
const char stream_id_video4[] = "\xE6";
const char stream_id_video5[] = "\xE7";
const char stream_id_video6[] = "\xE8";
const char stream_id_video7[] = "\xE9";
const char stream_id_video8[] = "\xEA";
const char stream_id_audio1[] = "\xC0";
const char stream_id_audio2[] = "\xC1";
const char stream_id_audio3[] = "\xC2";
const char stream_id_audio4[] = "\xC3";
const char stream_id_audio5[] = "\xC4";
const char stream_id_audio6[] = "\xC5";
const char stream_id_audio7[] = "\xC6";
const char stream_id_audio8[] = "\xC7";
const char stream_id_padding[] = "\xBE";
const char end_code[] = "\x00\x00\x01\xB9";
////////////////////////////////////////////////////
// Methods
////////////////////////////////////////////////////
/**
* SCR stands for System Clock Reference
*/
inline uint32_t SCR(uint32_t previous_SCR,
uint32_t pack_header_size,
uint32_t packets_per_pack,
uint32_t packet_data_size,
uint32_t Rmux)
{
// To prevent a crash when doing division.
if(Rmux == 0) Rmux = 1;
return previous_SCR + (uint32_t)((double)(pack_header_size +
(packets_per_pack * packet_data_size)) *
(double)CLOCK_90KHZ / (double)Rmux);
}
/**
* Calculates Rmux according to subclause A.6.4
* mux stands for multiplexing and R for Rate,
* so Rmux is the rate of the multiplexing.
* IMPORTANT: The formula is wrong...
* See
* https://www.iso.org/obp/ui/#iso:std:iso-iec:11172:-1:ed-1:v1:cor:2:v1:en
* for the correct formula:
* Rmux = (video_data_rate + audio_data_rate) *
* packet_header_size + pack_header_size / packets_per_pack
* ( 1 + ---------------------------------------------------------- )
* packet_data_size
*/
inline uint32_t Rmux(uint32_t video_data_rate,
uint32_t audio_data_rate,
uint32_t packet_header_size,
uint32_t pack_header_size,
uint32_t packets_per_pack,
uint32_t packet_data_size)
{
// To prevent a crash when doing division.
if(packets_per_pack == 0) packets_per_pack = 1;
if(packet_data_size == 0) packet_data_size = 1;
return (uint32_t)(
((double)video_data_rate + (double)audio_data_rate) *
(1.0 + ((double)packet_header_size + (double)pack_header_size / (double)packets_per_pack)
/ (double)packet_data_size)
);
}
};
#endif/*__MIAV_ISO11172_1_H__*/
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