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PSI: parse multiple sections correctly #27
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@@ -241,7 +243,7 @@ func parsePSISectionHeader(i *astikit.BytesIterator) (h *PSISectionHeader, offse | |||
h.PrivateBit = bs[0]&0x40 > 0 | |||
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// Section length | |||
h.SectionLength = uint16(bs[0]&0xf)<<8 | uint16(bs[1]) | |||
h.SectionLength = uint16(bs[0]&3)<<8 | uint16(bs[1]) |
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FYI: I always use this copy of spec: http://www.itu.int/rec/T-REC-H.222.0-201410-S/en
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On page 50 it says the section_length is only 10 bits:
section_length – This is a 12-bit field, the first two bits of which shall be '00'. The remaining 10 bits specify the number of bytes of the section, starting immediately following the section_length field, and including the CRC. The value in this field shall not exceed 1021 (0x3FD).
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Fair enough, I missed that one. Can you please fix this one in muxer as well?
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To be honest I don't quite get why removing || tableID.isUnknown()
would fix your issue here 🤔 Can you explain it a little bit?
data_psi.go
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@@ -120,6 +120,9 @@ func parsePSIData(i *astikit.BytesIterator) (d *PSIData, err error) { | |||
err = fmt.Errorf("astits: parsing PSI table failed: %w", err) | |||
return | |||
} | |||
if stop { |
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Can you just replace this by an else if
?
The issue was that when an unknown table was seen previously, parsing stopped altogether. This means that a known table later in the same packet (such as the program_map) was ignored altogether. |
OK, got it. In that case, I feel like doing the following would better fix the problem and clean everything behind:
What do you think? |
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cc #25