# Streamed HLS has wrong primary\_pic\_type of AUD.

**URL:** <https://community.wowza.com/t/streamed-hls-has-wrong-primary-pic-type-of-aud/52707>\
**Category:** Wowza Streaming Engine\
**Created:** [January 23, 2019, 5:49pm UTC](https://community.wowza.com/t/streamed-hls-has-wrong-primary-pic-type-of-aud/52707 "2019-01-23T17:49:15Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Tsuyoshi\_Hatta1](https://avatars.discourse-cdn.com/v4/letter/t/71c47a/32.png) [@Tsuyoshi\_Hatta1](https://community.wowza.com/u/Tsuyoshi_Hatta1)\
**Post date:** [January 23, 2019, 5:49pm UTC](https://community.wowza.com/t/streamed-hls-has-wrong-primary-pic-type-of-aud/52707/1 "2019-01-23T17:49:15Z")

</div>

Hello,

We stream HLS from mp4 file which has h.264 movie and AAC audio by using Wowza Streaming Engine 4.7.6.  
It seems that streamed mpeg-ts has wrong primary\_pic\_type of AUD.  
(source mp4 file does not have AUD)

According to H.264 specification, upper 3 bits of 6th bytes is primary\_pic\_type.

Here are captured AUD.  
●Captured AUD from Wowza  
・I-slice  
0x00 0x00 0x00 0x01 0x09 0x10 primary\_pic\_type is 0  
・P-slice  
0x00 0x00 0x00 0x01 0x09 0x30 primary\_pic\_type is 1  
・B-slice  
0x00 0x00 0x00 0x01 0x09 0x30 primary\_pic\_type is 1

●Captured AUD from Another one  
・I-slice  
0x00 0x00 0x00 0x01 0x09 0x10 primary\_pic\_type is 0  
・P-slice  
0x00 0x00 0x00 0x01 0x09 0x30 primary\_pic\_type is 1  
・B-slice  
0x00 0x00 0x00 0x01 0x09 0x50 primary\_pic\_type is 2

●Captured AUD from FFmpeg  
・I-slice  
0x00 0x00 0x00 0x01 0x09 0xf0 primary\_pic\_type is 7  
・P-slice  
0x00 0x00 0x00 0x01 0x09 0xf0 primary\_pic\_type is 7  
・B-slice  
0x00 0x00 0x00 0x01 0x09 0xf0 primary\_pic\_type is 7

primary\_pic\_type means here.  
0: I  
1: I, P  
2: I, P, B  
3: SI  
4: SI, SP  
5: I, SI  
6: I, SI, P, SP  
7: I, SI, P, SP, B

It seems that B-slice of AUD should be primary\_pic\_type = 2. What do you think?

Because some of Japanese TV occur block noise. When I had modify all AUD as primary\_pic\_type = 7, it does not occur…  
Could you please have a check and fix this? Thanks.

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<div class="post-metadata">

**Author:** ![Tsuyoshi\_Hatta1](https://avatars.discourse-cdn.com/v4/letter/t/71c47a/32.png) [@Tsuyoshi\_Hatta1](https://community.wowza.com/u/Tsuyoshi_Hatta1)\
**Post date:** [January 30, 2019, 1:04am UTC](https://community.wowza.com/t/streamed-hls-has-wrong-primary-pic-type-of-aud/52707/2 "2019-01-30T01:04:10Z")

</div>

Hello,

Does anyone have any comment?