H265 帧类型判断

请狗日的360doc不要转载。

参见ffmpeg中hevcdec.c hevc_probe函数(我的ffmpeg版本2.8.2)

和264的&0x1f不同。265是

int type = (code & 0x7E)>>1;

switch (type) {
case NAL_VPS:        vps++;  break;
case NAL_SPS:        sps++;  break;
case NAL_PPS:        pps++;  break;
case NAL_BLA_N_LP:
case NAL_BLA_W_LP:
case NAL_BLA_W_RADL:
case NAL_CRA_NUT:
case NAL_IDR_N_LP:
case NAL_IDR_W_RADL: irap++; break;
}
这里应该是统计帧个数的。可以看出NAL_BLA_N_LP到NAL_IDR_W_RADL都算I帧。

对此ffmpeg 中 hevc.h 如下定义

NAL_TRAIL_N = 0,

NAL_TRAIL_R = 1,

NAL_TSA_N = 2,

NAL_TSA_R = 3,

NAL_STSA_N = 4,

NAL_STSA_R = 5,

NAL_RADL_N = 6,

NAL_RADL_R = 7,

NAL_RASL_N = 8,

NAL_RASL_R = 9,

NAL_BLA_W_LP = 16,

NAL_BLA_W_RADL = 17,

NAL_BLA_N_LP = 18,

NAL_IDR_W_RADL = 19,

NAL_IDR_N_LP = 20,

NAL_CRA_NUT = 21,

NAL_VPS = 32,

NAL_SPS = 33,

NAL_PPS = 34,

NAL_AUD = 35,

NAL_EOS_NUT = 36,

NAL_EOB_NUT = 37,

NAL_FD_NUT = 38,

NAL_SEI_PREFIX = 39,

NAL_SEI_SUFFIX = 40,

我的猜测是从1到9都是P帧

16-21是I帧

其余SPS PPS VPS SUFFIX_SEI_NUT