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Fix wrong profile. Fix issue #102

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Alexey Safronov
2020-08-07 00:59:26 +03:00
parent 21eb9a6a1b
commit 59b218e410
1 changed files with 1 additions and 1 deletions
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@@ -681,7 +681,7 @@ If we skip the first synchronization marker we can decode the **first byte** to
For instance the first byte after the synchronization marker is `01100111`, where the first bit (`0`) is to the field **forbidden_zero_bit**, the next 2 bits (`11`) tell us the field **nal_ref_idc** which indicates whether this NAL is a reference field or not and the rest 5 bits (`00111`) inform us the field **nal_unit_type**, in this case, it's a **SPS** (7) NAL unit.
The second byte (`binary=01100100, hex=0x64, dec=100`) of an SPS NAL is the field **profile_idc** which shows the profile that the encoder has used, in this case, we used the **[constrained high-profile](https://en.wikipedia.org/wiki/H.264/MPEG-4_AVC#Profiles)**, it's a high profile without the support of B (bi-predictive) slices.
The second byte (`binary=01100100, hex=0x64, dec=100`) of an SPS NAL is the field **profile_idc** which shows the profile that the encoder has used, in this case, we used the **[high profile](https://en.wikipedia.org/wiki/H.264/MPEG-4_AVC#Profiles)**. Also the third byte contains several flags which determine the exact profile (like constrained or progressive). But in our case the third byte is 0x00 and therefore the encoder has used just high profile.
![SPS binary view](/i/minimal_yuv420_bin.png "SPS binary view")