1+ #ifndef RTC_VP8_NAL_UNIT_H
2+ #define RTC_VP8_NAL_UNIT_H
3+
4+ #if RTC_ENABLE_MEDIA
5+
6+ #include " common.hpp"
7+ #include " nalunit.hpp"
8+ #include < cassert>
9+ #include < cstdint>
10+ #include < vector>
11+
12+ /*
13+ * Example “VP8NalUnit” derived from your base NalUnit class, mirroring
14+ * how "H265NalUnit" is done. In VP8, there is no true NAL unit concept,
15+ * but we can still parse the "VP8 payload descriptor" (RFC 7741 sec. 4.2)
16+ * from the front of the data, and store or retrieve key bits.
17+ *
18+ * IMPORTANT: We avoid calling NalUnit(std::move(data), Type) since
19+ * NalUnit has no such two-argument constructor. Instead, we do
20+ * NalUnit(std::move(data)) just like your H265 code.
21+ */
22+
23+ namespace rtc {
24+
25+ #pragma pack(push, 1)
26+
27+ // The mandatory first byte of the VP8 payload descriptor.
28+ // (RFC 7741, Section 4.2)
29+ struct VP8PayloadDescriptorFirstByte {
30+ uint8_t raw = 0 ;
31+
32+ bool hasExtension () const { return (raw & 0x80 ) != 0 ; } // X
33+ bool isNonReference () const { return (raw & 0x20 ) != 0 ; } // N
34+ bool isStartOfPartition () const { return (raw & 0x10 ) != 0 ; } // S
35+ uint8_t partitionIndex () const { return (raw & 0x07 ); } // PID
36+
37+ void setHasExtension (bool val) {
38+ if (val) raw |= (1 << 7 );
39+ else raw &= ~(1 << 7 );
40+ }
41+ void setNonReference (bool val) {
42+ if (val) raw |= (1 << 5 );
43+ else raw &= ~(1 << 5 );
44+ }
45+ void setStartOfPartition (bool val) {
46+ if (val) raw |= (1 << 4 );
47+ else raw &= ~(1 << 4 );
48+ }
49+ void setPartitionIndex (uint8_t pid) {
50+ raw = (raw & 0xF8 ) | (pid & 0x07 );
51+ }
52+ };
53+
54+ // Optional extension byte if the X bit = 1.
55+ struct VP8PayloadDescriptorExtensionByte {
56+ uint8_t raw = 0 ;
57+
58+ bool hasPictureID () const { return (raw & 0x80 ) != 0 ; } // I
59+ bool hasTL0PICIDX () const { return (raw & 0x40 ) != 0 ; } // L
60+ bool hasTID () const { return (raw & 0x20 ) != 0 ; } // T
61+ bool hasKEYIDX () const { return (raw & 0x10 ) != 0 ; } // K
62+ };
63+
64+ #pragma pack(pop)
65+
66+ // “VP8NalUnit” extends NalUnit but is really a container for one VP8 frame
67+ // (or partial frame) plus its RTP "payload descriptor" bits.
68+ struct VP8NalUnit : public NalUnit {
69+ public:
70+ // Match your H265NalUnit style:
71+ VP8NalUnit () : NalUnit(NalUnit::Type::VP8) {}
72+ VP8NalUnit (size_t size, bool includingHeader = true )
73+ : NalUnit(size, includingHeader, NalUnit::Type::VP8) {}
74+ VP8NalUnit (binary &&data)
75+ : NalUnit(std::move(data)) {} // call NalUnit(binary && data)
76+ VP8NalUnit (const VP8NalUnit&) = default ;
77+
78+ // Parse the VP8 payload descriptor from the beginning of data().
79+ // Returns how many bytes of descriptor were consumed.
80+ size_t parseDescriptor ();
81+
82+ // The actual VP8 bitstream data after the descriptor.
83+ binary payload () const ;
84+
85+ // If this frame is a keyframe or not (based on the "P" bit in the
86+ // first 3 bytes of the actual VP8 payload when partitionIndex=0).
87+ bool isKeyFrame () const { return mIsKeyFrame ; }
88+
89+ // The “S bit” in the first descriptor byte.
90+ bool isStartOfPartition () const { return mFirstByte .isStartOfPartition (); }
91+
92+ VP8PayloadDescriptorFirstByte mFirstByte {0 };
93+
94+ // PictureID if present in the extension. (RFC 7741 Section 4.2)
95+ uint16_t pictureID () const { return mPictureID ; }
96+
97+ // For demonstration, generating multiple “fragments” from a large frame
98+ // simulating the style of H.265 FU logic, though not standardized for VP8:
99+ static std::vector<binary> GenerateFragments (const std::vector<VP8NalUnit> &units,
100+ size_t maxFragmentSize);
101+ std::vector<VP8NalUnit> generateFragments (size_t maxFragmentSize) const ;
102+
103+ private:
104+ bool mHasExtension = false ;
105+ VP8PayloadDescriptorExtensionByte mExtByte {0 };
106+
107+ bool mHasPictureID = false ;
108+ uint16_t mPictureID = 0 ;
109+ bool mIsKeyFrame = false ; // if “P=0” in the first-byte of actual VP8 data
110+
111+ // Implementation detail: parse out extension fields if X=1, etc.
112+ };
113+
114+ } // namespace rtc
115+
116+ #endif /* RTC_ENABLE_MEDIA */
117+
118+ #endif /* RTC_VP8_NAL_UNIT_H */
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