www.makemkv.com

I've noticed that ripping 4k discs seems to be pretty sensitive. I'll have a disc that plays fine on my Oppo 4k blu ray player, but will get a good way through ripping only to have "corrupt or invalid at offset". When I inspect the disc for scratches it will look almost pristine. Usually if I look hard enough I can find some tiny hairline little scratch or something. Often trying someone else's disc will result in a full errorless rip. So definitely not a hashed key issue or anything.

So I understand that the problem lies either in the drive (an LG BD-RE WH16NS60) or in MakeMKV's error handling. But is there any tips people have to try and get the problem discs to rip all the way through? I've tried wiping with a microfiber cloth and even using lens cleaner on the disc with the cloth, but no real results with that.

Playing in a UHD BD player, any errors are skipped over. Losing a sector or five to a scratch will usually be ignored.

Yes, the smaller holes used for UHD amplify the effects of scratches. How a disk looks to our naked eyes means nothing when you're trying to focus a laser on a string of holes that small. Especially when there are stacked layers of them.

My advice for dealing with them - rip them as soon as they arrive, before they have a chance to get damaged in any way. It is still sometimes necessary to clean them "fresh from the package", but getting them ripped quickly, and put into storage safely, is #1 priority.

After that, they're processed and put onto a pair of storage servers, accessible to all the TVs in the house, and the physical disks are not touched again unless something bad happens to the storage servers, OR some better way of encoding them comes along that is workable.

When I first got this set up, I tried to rip four disks, two of them failed. I got them both to work by cleaning with a microfiber cloth and trying a couple times.

Then, for a separate reason I downgraded my drive from 1.02 to 1.00 firmware, specifically the WH16NS60 1.00d firmware. Since then I've ripped a dozen more disks without a single error. Could be coincidence, but that's been my experience.

Get a 2nd drive. My LG WH16NS40 was having problems with a few UHD's and I thought it was failing so I bought an ASUS BW-16D1HT and it read them 1st try. The LG still works fine too. I use them both. If one won't read the disc the other will. I haven't come across a disc yet that neither will read.

Woodstock wrote: ↑

Thu Aug 08, 2019 1:10 am

Playing in a UHD BD player, any errors are skipped over. Losing a sector or five to a scratch will usually be ignored.

The amount of data in a tiny scratch is probably pretty large though. Why wouldn't we see macroblocking or the picture freeze in such cases?

On one of my discs that I can't rip that has a visible scratch, it indeed macroblocks, freezes, and skips an entire section of the movie. It all depends on the player and how bad the defect is on the disc.

Hi,

I had similar problems with my last 20 movies, I then thought my drive was failing even though the rips were between 100-150.

I then realized in the logs errors were sneaking in, bought two brand new drives (backups) and same thing.

Then I remembered the same old thread of about how crap the disc are and did 50% alcohol and 50% water and wiped good like a year ago.

Sure enough it went away and just finished re re-ripping brand new 20 disc and making sure each movie played well. It is exhausting. When I went back each BRAND NEW disc had human finger prints, specs, film grease from the black cases.

These disc and who makes them, its just terrible

I am now dealing with Finding Nemo which will not rip even after cleaning in all three drives. Its brand new and STILL exchanged it for another copy and sure enough that copy had more finger prints. cleaned it down and now still fighting hash errors.

I was just about to make a post to warn people but posting here is good enough. I have an excel sheet I printed to keep track of all the re-rips.

good luck