feat: add parser for SCTE

[Wkkkkk]

To break from an error ASAP, we removed the error chain. In case of faulty ts files, we might see errors like follows.

{"pid":134,"codec":"SCTE35","type":"cue"}
{"pid":256,"codec":"AVC","type":"video"}
{"pid":257,"codec":"AAC","type":"audio"}
{"SDT":[{"serviceId":1,"descriptors":[{"serviceName":"Service01","providerName":"FFmpeg"}]}]}
2024/01/24 13:49:31 cannot get payload for packet on PID 134 Error=packet does not contain payload
exit status 1

[Wkkkkk]

Hi @tobbee, I tried to avoid a different parser for scte35 but found no solution yet. Instead, I removed the buffering by checking the options in mp2ts-info.

func parse(ctx context.Context, w io.Writer, f io.Reader, o internal.Options) error {
    // Parse either general information, or scte35 (by default)
    if o.ShowService {
        err := internal.ParseInfo(ctx, w, f, o)
        if err != nil {
            return err
        }
    } else if o.ShowSCTE35 {
        err := internal.ParseSCTE35(ctx, w, f, o)
        if err != nil {
            return err
        }
    }

    return nil
}

Together with other changes, we might have outputs like the following:

go run . -indent=false ~/Downloads/ts_with_scte35.ts

{"pid":289,"codec":"AVC","type":"video"}
{"pid":545,"codec":"AAC","type":"audio"}
{"pid":546,"codec":"AAC","type":"audio"}
{"pid":53,"codec":"SCTE35","type":"cue"}
{"pid":53,"spliceCommand":{"type":"SpliceInsert","eventId":8,"pts":0}}
{"pid":53,"spliceCommand":{"type":"SpliceInsert","eventId":1,"pts":0,"duration":2700000,"outOfNetwork":true}}
{"pid":53,"spliceCommand":{"type":"SpliceInsert","eventId":1,"pts":0}}
{"pid":53,"spliceCommand":{"type":"SpliceInsert","eventId":2,"pts":0,"duration":4500000,"outOfNetwork":true}}

go run . -indent=false -service ~/Downloads/ts_with_scte35.ts

{"pid":289,"codec":"AVC","type":"video"}
{"pid":545,"codec":"AAC","type":"audio"}
{"pid":546,"codec":"AAC","type":"audio"}
{"pid":53,"codec":"SCTE35","type":"cue"}
{"SDT":[{"serviceId":1,"descriptors":[{"serviceName":"A1Now","providerName":"Sportradar"}]}]}

[Wkkkkk]

One possibility is to implement the service table parsing with gots ourselves so that we will have one parsing logic for both SCTE-markers and service tables (or any other PSI tables).

[Wkkkkk]

While testing, it was noticed that the PTS in SpliceInsertCommand is missing. This has been fixed in the last commit.

go run . -indent=false ~/Downloads/80s_with_ad.ts

{"pid":256,"codec":"AVC","type":"video"}
{"pid":257,"codec":"AAC","type":"audio"}
{"pid":1001,"codec":"SCTE35","type":"cue"}
{"pid":1001,"spliceCommand":{"type":"SpliceInsert","eventId":255,"pts":1032000,"duration":1800000,"outOfNetwork":true}}