Opened 16 years ago

Closed 16 years ago

#113 closed patch (invalid)

mpeg (and other) sequence number wrap not handled

Reported by: Mark Spieth <mspieth@…> Owned by: Isaac Richards
Priority: minor Milestone: unknown
Component: mythtv Version:
Severity: medium Keywords:
Cc: Ticket locked: no


the sequence number for mpeg wraps at 33 bits which is not compensated for after timestamp normalization. this can cause audio and video timestamp mismatches and plays badly as a result. transcoding is affected too and is less recoverable.

this patch was part of the generic libavformat seek support patch but didnt get included. I feel it is important.

It offsets the pts for any format at file/stream open time to 0, thus enabling maximum uncorrupted playtime (26.5 hours for mpeg). Done this way it is transparent to transcode and will work for any format.

Equivalent compensation code is already in avformatdecoder.cpp seek which shouldnt be there if this patch is not applied.

Attachments (1)

mythtv_avf_seq.patch (2.0 KB) - added by Mark Spieth <mspieth@…> 16 years ago.

Download all attachments as: .zip

Change History (2)

Changed 16 years ago by Mark Spieth <mspieth@…>

Attachment: mythtv_avf_seq.patch added

comment:1 Changed 16 years ago by Isaac Richards

Resolution: invalid
Status: newclosed

I'd really prefer to fix this properly (ie., have the player handle the timestamp wrapping), instead of just covering it up like this. Do you have a small-ish sample of such content?

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