AVCDecoderConfiguration语法格式分析

AVCDecoderConfiguration语法

aligned(8) class AVCDecoderConfigurationRecord {
    unsigned int(8) configurationVersion = 1;
    unsigned int(8) AVCProfileIndication;
    unsigned int(8) profile_compatibility;
    unsigned int(8) AVCLevelIndication;
    bit(6) reserved = ‘111111’b;
    unsigned int(2) lengthSizeMinusOne;
    bit(3) reserved = ‘111’b;

    unsigned int(5) numOfSequenceParameterSets;
    for (i=0; i< numOfSequenceParameterSets; i++) {
        unsigned int(16) sequenceParameterSetLength ;
        bit(8*sequenceParameterSetLength) sequenceParameterSetNALUnit;
    }

    unsigned int(8) numOfPictureParameterSets;
    for (i=0; i< numOfPictureParameterSets; i++) {
        unsigned int(16) pictureParameterSetLength;
        bit(8*pictureParameterSetLength) pictureParameterSetNALUnit;
    }
}

AVCDecoderConfiguration句意

sequenceParameterSetNALUnit：包含了SPS NAL Unit，第一个字节为0x67，然后即是seq_parameter_set_rbsp()，其语法如表1所示。

pictureParameterSetNALUnit：包含了PPS NAL Unit，第一个字节为0x68，然后即是pic_parameter_set_rbsp()，其语法如表2所示。

表1 序列参数集（SPS）RBSP语法

表2 图像参数集（PPS）RBSP语法