Interworking issue with Firefox nightly (H.264)

[Seunghan Choi]

Hi, Team.

I want to interwork telepresence(doubango) with Firefox nightly (H.264) in H.264.

I found that the H.264 NAL type(packetizing type) of Firefox is STAP-A.

But, you know, doubango(telepresence) is not implemented about the processing of STAP-A NAL type.

So, I am implementing the processing of STAP-A NAL type in tinydav (in doubango telepresence code)

the following code,

 int tdav_codec_h264_get_pay(const void* in_data, tsk_size_t in_size, const void** out_data, tsk_size_t *out_size, tsk_bool_t* append_scp)

{

const uint8_t* pdata = (const uint8_t*)in_data;

uint8_t nal_type;

if(!in_data || !in_size || !out_data || !out_size){

TSK_DEBUG_ERROR("Invalid parameter");

return -1;

}

 

*out_data = tsk_null;

*out_size = 0;

 

/* 5.3. NAL Unit Octet Usage

  +---------------+

      |0|1|2|3|4|5|6|7|

      +-+-+-+-+-+-+-+-+

      |F|NRI|  Type   |

      +---------------+

*/

switch((nal_type = (pdata[0] & 0x1F))){

case undefined_0:

case undefined_30:

case undefined_31:

//modified by shchoi 파이어폭스 NAL TYPE은 STAP-A(24)

//case stap_a:

case stap_b:

case mtap16:

case mtap24:

case fu_b:

break;

//inserted by shchoi

case stap_a:

*append_scp = tsk_true;//(nal_type != 7 && nal_type != 8); // SPS or PPS

return tdav_codec_h264_get_stapa_pay(pdata, in_size, out_data, out_size, append_scp);

case fu_a:

return tdav_codec_h264_get_fua_pay(pdata, in_size, out_data, out_size, append_scp);

default: /* NAL unit (1-23) */

*append_scp = tsk_true;//(nal_type != 7 && nal_type != 8); // SPS or PPS

return tdav_codec_h264_get_nalunit_pay(pdata, in_size, out_data, out_size);

}

 

TSK_DEBUG_WARN("%d not supported as valid NAL Unit type", (*pdata & 0x1F));

return -1;

}

 

//inserted by shchoi

int tdav_codec_h264_get_stapa_pay(const uint8_t* in_data, tsk_size_t in_size, const void** out_data, tsk_size_t *out_size, tsk_bool_t* append_scp)

{

/*

if (in_size <= H264_FUA_HEADER_SIZE){

TSK_DEBUG_ERROR("Too short");

return -1;

}

*/

/* RFC 3984 - 5.7.1 Single-Time Aggregation Packet (STAP-A)

 

0                   1                   2                   3

0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

|                          RTP Header                           |

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

|STAP-A NAL HDR |         NALU 1 Size           | NALU 1 HDR    |

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

|                         NALU 1 Data                           |

:                                                               :

+               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

|               | NALU 2 Size                   | NALU 2 HDR    |

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

|                         NALU 2 Data                           |

:                                                               :

|                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

|                               :...OPTIONAL RTP padding        |

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

*/

int nal_size = 0;

uint8_t nal_type;

 

nal_size = (in_data[1] << 8) | in_data[2];

 

nal_type = (in_data[3] & 0x1F);

 

*out_data = (in_data + 1 + 2);

*out_size = nal_size - 2;

      return 0;

}

When telepresence is connected with firefox nightly(version 42.0a1) , the following error happned.

............................

[h264 @ 0x8c9b620] non-existing PPS 12 referenced

[h264 @ 0x8c9b620] decode_slice_header error

[h264 @ 0x8c9b620] no frame!

[h264 @ 0x8c9b620] non-existing PPS 12 referenced

[h264 @ 0x8c9b620] decode_slice_header error

[h264 @ 0x8c9b620] no frame!

.............................

the H.264 codec of the doubango telepresence is ffmpeg.

Please, someone helps me.

Thanks.

From seunghan.