anc_payloads.h

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// -------------------------------------------------------------------------------------------
// Copyright Amazon.com Inc. or its affiliates. All Rights Reserved.
// This file is part of the AWS CDI-SDK, licensed under the BSD 2-Clause "Simplified" License.
// License details at: https://github.com/aws/aws-cdi-sdk/blob/mainline/LICENSE
// -------------------------------------------------------------------------------------------
 
#ifndef ANC_PAYLOADS_H__
#define ANC_PAYLOADS_H__
 
#include "cdi_avm_payloads_api.h"
 
#include <stdint.h>
#include <stdbool.h>
 
//*********************************************************************************************************************
//***************************************** START OF DEFINITIONS AND TYPES ********************************************
//*********************************************************************************************************************
 
struct AncillaryDataPacket
{
    bool is_color_difference_channel;
    unsigned line_number:11;
    unsigned horizontal_offset:12;
    bool is_valid_source_stream_number;
    unsigned source_stream_number:7;
    uint8_t did;
    uint8_t sdid;
    uint8_t data_count;
    uint16_t user_data[255 + 4];
};
 
struct AncillaryDataPayloadErrors
{
    uint32_t checksum;
    int checksum_errors;
    int parity_errors;
};
 
struct AncillaryDataPayloadHeader
{
    uint16_t ancillary_data_packet_count;
    CdiFieldKind field_kind;
};
 
//*********************************************************************************************************************
//******************************************* START OF PUBLIC FUNCTIONS ***********************************************
//*********************************************************************************************************************
 
inline static bool Parity8(uint8_t value)
{
    // From https://graphics.stanford.edu/~seander/bithacks.html#ParityParallel
    unsigned v = value;
    v ^= v >> 4;
    v &= 0xf;
    return (0x6996 >> v) & 1;
}
 
inline static uint16_t WithParityBits(uint8_t value)
{
    uint16_t parity = Parity8(value);
    return (!parity << 9) + (parity << 8) + value;
}
 
inline static uint8_t CheckParityBits(uint16_t raw_word, int* parity_errors_ptr)
{
    uint16_t parity = Parity8(raw_word);
    if ((raw_word & 0x100) >> 8 != parity || (raw_word & 0x200) >> 9 == parity) {
        (*parity_errors_ptr)++;
    }
    return 0xff & raw_word;
}
 
void ParseAncillaryDataPayloadHeader(const uint32_t* payload_net_data_ptr, uint16_t* packet_count_ptr,
    CdiFieldKind* field_kind_ptr);
 
void ParseAncillaryDataPacketHeader(const uint32_t* packet_net_data_ptr, struct AncillaryDataPacket* packet_ptr,
    struct AncillaryDataPayloadErrors* payload_errors);
 
int ParseAncillaryDataPacket(const uint32_t* packet_net_data_ptr, struct AncillaryDataPacket* packet_ptr,
    struct AncillaryDataPayloadErrors* payload_errors_ptr);
 
int GetAncillaryDataPacketSize(int data_count);
 
void WriteAncillaryDataPayloadHeader(uint32_t* payload_net_data_ptr, uint16_t packet_count, CdiFieldKind field_kind);
 
void WriteAncillaryDataPacketHeader(uint32_t* packet_net_data_ptr, const struct AncillaryDataPacket* packet_ptr,
    uint32_t* checksum_ptr);
 
int WriteAncillaryDataPacket(uint32_t* packet_net_data_ptr, const struct AncillaryDataPacket* packet_ptr);
 
#endif // ANC_PAYLOADS_H__