AV sync issues

[cpaqf1]

Hello,

Just wondering, are these a problem when ripping a bluray ISO ? or does MakeMKV fix them?

tia

AV sync issue in stream 0 at 0:00:00.166 : video frame timecode differs by +66.733ms
AV sync issue in stream 0 at 0:00:00.233 : video frame timecode differs by +100.1ms
AV sync issue in stream 0 at 0:02:46.533 : video stream has 16 frames with invalid timecodes
AV sync issue in stream 0 at 0:00:00.200 : video frame timecode differs by +66.733ms
AV sync issue in stream 0 at 0:07:57.810 : video stream has 17 frames with invalid timecodes

and this from another ISO, but this one is all at "00:00:00"

AV sync issue in stream 1 at 0:00:00 : 0 frame(s) dropped to reduce audio skew to +4.666ms
AV sync issue in stream 2 at 0:00:00 : 0 frame(s) dropped to reduce audio skew to +4.666ms
AV sync issue in stream 3 at 0:00:00 : 0 frame(s) dropped to reduce audio skew to +18ms
AV sync issue in stream 4 at 0:00:00 : 0 frame(s) dropped to reduce audio skew to +26ms
AV sync issue in stream 5 at 0:00:00 : 0 frame(s) dropped to reduce audio skew to +26ms
AV sync issue in stream 1,2 at 0:00:00 with duration of 4.666ms : encountered overlapping frame, audio skew is +4.666ms
AV sync issue in stream 3 at 0:00:00 with duration of 18ms : encountered overlapping frame, audio skew is +18ms
AV sync issue in stream 4,5 at 0:00:00 with duration of 26ms : encountered overlapping frame, audio skew is +26ms

[Woodstock]

Differences in the millisecond range are rarely a problem; they can come about when following the "seamless branching" chain, where multiple m2ts files make up a particular title.

Sometimes, you will see gaps in the multiple seconds range - The worst I've seen posted here was over an hour (3600 seconds). Those are probably problems with the way the disk is authored.

[cpaqf1]

Differences in the millisecond range are rarely a problem; they can come about when following the "seamless branching" chain, where multiple m2ts files make up a particular title.

Sometimes, you will see gaps in the multiple seconds range - The worst I've seen posted here was over an hour (3600 seconds). Those are probably problems with the way the disk is authored.

okay, thank you for the info.

one last question.

I just ripped the martian (2015) I see a lot of dropped frames here, presumably to sync with the audio. Out of curiosity, is audio ever modified, or only video (ie frame drops) ?

AV sync issue in stream 1,2 at 0:18:12.049 with duration of 4.041ms : encountered overlapping frame, audio skew is +4.041ms
AV sync issue in stream 3,4 at 0:18:12.049 with duration of 14.708ms : encountered overlapping frame, audio skew is +14.708ms
AV sync issue in stream 1,2 at 0:20:03.410 with duration of 9.416ms : encountered overlapping frame, audio skew is +13.458ms
AV sync issue in stream 1,2 at 0:20:03.424 with duration of 10.666ms : 1 frame(s) dropped to reduce audio skew to +2.791ms
AV sync issue in stream 3,4 at 0:20:03.410 with duration of 30.75ms : encountered overlapping frame, audio skew is +45.458ms
AV sync issue in stream 3,4 at 0:20:03.456 with duration of 32ms : 1 frame(s) dropped to reduce audio skew to +13.458ms
AV sync issue in stream 1,2 at 0:20:44.326 with duration of 1.458ms : encountered overlapping frame, audio skew is +4.25ms
AV sync issue in stream 3,4 at 0:20:44.326 with duration of 12.125ms : encountered overlapping frame, audio skew is +25.583ms
AV sync issue in stream 1,2 at 0:21:19.945 with duration of 7.75ms : encountered overlapping frame, audio skew is +12ms
AV sync issue in stream 1,2 at 0:21:19.957 with duration of 10.666ms : 1 frame(s) dropped to reduce audio skew to +1.333ms
AV sync issue in stream 3,4 at 0:21:19.945 with duration of 29.083ms : encountered overlapping frame, audio skew is +54.666ms
AV sync issue in stream 3,4 at 0:21:20 with duration of 32ms : 1 frame(s) dropped to reduce audio skew to +22.666ms

and can I safely disable AV sync errors? will it alert me anyways if I come across a serious sync issue like you mentioned (3600 seconds)?

I really appreciate the work you guys put into all this, I plan on buying MakeMKV very soon.

[Woodstock]

If you suppress AV sync errors, it would suppress the "grossly bad" ones, too. It's kind of an "all or nothing" deal.

Personally, I ignore most of what's in the log unless I get a "failed to save" message.

[cpaqf1]

If you suppress AV sync errors, it would suppress the "grossly bad" ones, too. It's kind of an "all or nothing" deal.

Personally, I ignore most of what's in the log unless I get a "failed to save" message.

Alright,

this is truly the last question. Does MakeMKV ever modify audio, or only video (ie frame dropped to try and resync) ?

thanks

[Woodstock]

Unless you ask it to, no it does not.

Using a profile OTHER THAN the default (example is the FLAC profile), you can specify that certain audio codecs be converted to FLAC, a lossless, open-source codec.

I have not made use of that feature, so I cannot say how well it works. I prefer to pass the audio tracks through unchanged, and let handbrake deal with them when I recode the files to smaller sizes.