50 lines
1.4 KiB
Go
50 lines
1.4 KiB
Go
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package astits
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// NITData represents a NIT data
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// Page: 29 | Chapter: 5.2.1 | Link: https://www.dvb.org/resources/public/standards/a38_dvb-si_specification.pdf
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type NITData struct {
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NetworkDescriptors []*Descriptor
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NetworkID uint16
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TransportStreams []*NITDataTransportStream
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}
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// NITDataTransportStream represents a NIT data transport stream
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type NITDataTransportStream struct {
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OriginalNetworkID uint16
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TransportDescriptors []*Descriptor
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TransportStreamID uint16
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}
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// parseNITSection parses a NIT section
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func parseNITSection(i []byte, offset *int, tableIDExtension uint16) (d *NITData) {
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// Init
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d = &NITData{NetworkID: tableIDExtension}
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// Network descriptors
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d.NetworkDescriptors = parseDescriptors(i, offset)
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// Transport stream loop length
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var transportStreamLoopLength = int(uint16(i[*offset]&0xf)<<8 | uint16(i[*offset+1]))
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*offset += 2
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// Transport stream loop
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transportStreamLoopLength += *offset
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for *offset < transportStreamLoopLength {
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// Transport stream ID
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var ts = &NITDataTransportStream{}
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ts.TransportStreamID = uint16(i[*offset])<<8 | uint16(i[*offset+1])
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*offset += 2
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// Original network ID
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ts.OriginalNetworkID = uint16(i[*offset])<<8 | uint16(i[*offset+1])
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*offset += 2
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// Transport descriptors
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ts.TransportDescriptors = parseDescriptors(i, offset)
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// Append transport stream
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d.TransportStreams = append(d.TransportStreams, ts)
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}
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return
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}
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