Lines in my Image

[Nicks Pics]

I just noticed this image on my external hard drive having these thin lines in it. (near the bottom of the image ) Here is a cropped sample of it. These lines were not there in the original image, but I have edited it and probably saved it in a couple different formats, this was a TIFF image. I just wanted to ask if anyone knows what made the lines? It wasn't the SD card on which it was first recorded, so it could have either been Lightroom when I saved it to TIFF, or something that happened to it while it was sitting on my external hard drive. It could have possibly been saved by GIMP, but probably it was Lightroom. I'd like to know if there is a problem in my system or if this is just a casual malfunction. Thanks to anyone who has an idea!

[Manfred M]

Looks like some form of data corruption to me. Somehow the data had an error in it when it was read into your software.

It could be one of those random one-time events or something more serious, indicating an issue with a failing hard drive. I'm not sure that this is a software issue per se, but it could be and if it is, I would be more suspicious of GIMP than Lightroom in this case.

I would say that I wouldn't be too concerned if it is a one-off event, but if you see it again, you might want to investigate some more.

[Bobobird]

Please supply a much much larger crop so that the "lines" and the data within shows more clearly.

At first glance it does look like some corruption while saving. If you see random colours in the lines that would be almost certainly corruption. The other could be the graphics driver or the hardware itself - overheated could lead to random corruption as well.

Save the ok version to another drive and see if the problem remains.

[IzzieK]

I had experienced that before but it was a long time ago so I forgot how I had solved it or did it go away on its own...I am afraid I am no help at all here...

[tao2]

Hi Nick,

been searching my bookmarks (without success ...so far). Sure ah read about this a long time ago . IIRC there were a couple of causes one was something tae do with layering/transparency coupled with using the PDF format tae transfer or store images. Something about Adobe (in particular) flattening the image, causing the lines. Ah know next to nothing about layering etc. so can't help there. Ah'll keep looking.

[DanK]

Why don't you follow the trail from the initial raw image, read into LR, to this one? If you saved all the images, it should be apparent at which stage the line was introduced.

[Nicks Pics]

Thank you all for sharing your insight on this, commenting, or other nice intentions about it. This is the largest res I have of this particular version of the image, at this point, but it does look like there are random colors in the lines to me. You can click to expand the image, (of course). I have re-saved this image from both lightroom and GIMP, and the new versions look free of imperfections. I generally try to keep my important files backed up other than on this one hard drive, just in case it fails. Given this, do you think it was most likely one of my editors, the ext. hard drive, or the computer overheating? As these are the main suggested potential scenarios.

[DanK]

I generally try to keep my important files backed up other than on this one hard drive, just in case it fails.

yes, this is important--also to protect against user error, which in my case, is far more common than equipment failures.

Given this, do you think it was most likely one of my editors, the ext. hard drive, or the computer overheating?

I am certainly not an engineer, but if the computer overheated (which has never happened to me or anyone I know), wouldn't it generate something more random than absolutely straight lines?

[Nicks Pics]

yes, this is important--also to protect against user error, which in my case, is far more common than equipment failures.

Right

I am certainly not an engineer, but if the computer overheated (which has never happened to me or anyone I know), wouldn't it generate something more random than absolutely straight lines?

I really don't know computers that well, it's just something someone suggested.

Thanks for the reply

[Manfred M]

Thank you all for sharing your insight on this, commenting, or other nice intentions about it. This is the largest res I have of this particular version of the image, at this point, but it does look like there are random colors in the lines to me. You can click to expand the image, (of course). I have re-saved this image from both lightroom and GIMP, and the new versions look free of imperfections. I generally try to keep my important files backed up other than on this one hard drive, just in case it fails. Given this, do you think it was most likely one of my editors, the ext. hard drive, or the computer overheating? As these are the main suggested potential scenarios.

Nick - I suspect that the most likely suspect would be the hard drive; it is the one part of your computer that will definitely fail over time. Bad blocks have been with us since the earliest hard drives. Error correction / detection mechanisms are designed to prevent this from happening, but nothing is perfect. Portable hard drives tend to be subjected to more knocks and are more likely to have damage done to them.

I suspect that it is likely not one of your editors; a bug like this would likely have been caught and corrected a long time ago. Pre-release testing is quite rigorous in commercial software, so chances of it slipping through a slight. Even non-commercial software like GIMP is unlikely to have a bug like this, although I suspect that the testing is less rigorous, the user user community would have reported this long ago.

Computer overheating; possible, but chances are that you would have seen other signs, random shut downs and reboots are pretty typical issues when the machine runs too hot.

[Dave Humphries]

Let me first say that I don't work with TIF files.

However, in my limited experience, if a file, such as a jpg, becomes corrupt on a Hard Drive, it usually becomes unopenable in any normal application.

I therefore suspect that the corruption occurred while the file was in the image editor's RAM (memory) and it was saved with the lines there.

Manfred has mentioned other reasons why the corrupt file is unlikely to be the cause.

[Nicks Pics]

Thanks for your help folks. I shall not worry too much more for now, other than to keep backing up my files, and keep a look out for the problem. I got my hard drive about 10 months ago, and still have room on it, but I don't know if it'll get filled up, or break first. How long do you expect your hard drives to last?

[Manfred M]

How long do you expect your hard drives to last?

Usually they either die quite quickly when they are new or else they can last for years (baring physical damage from being jarred or dropped). Nicely said, there is no way of predicting how long they will last.

[tao2]

Hi Nick, ah think ye can (almost) certainly rule out either a failing hard drive or bad sectors. PCs don't overheat tae the point of combustion, they shut down when they pass optimum temps and confusingly they can show the same symptoms as a failing hard drive. If it's only heat causing these problems that can be eliminated by a good clean and checking all fans and vents. Often thermal paste deteriorating at the CPU/motherboard junction, causes the PC tae operate hotter than normal. Many of these problems are simply solved by cleaning fans, cleaning the case interior, ensuring vents are not blocked against walls etc. and that they are clear of dust

A failing hard drive will exhibit many more problems than one line in one photo - inexplicable shutdowns, a general slowing down of PC operations, frequent app and screen freezing, BSOD (blue screen of death).

Files corrupted by bad sectors will...
a) Fail tae open
b) If able tae be opened will look like this (example 1), an extreme example but even small parts of a file like this will show that it's a corrupt file either from a bad sector or a fault when closing or saving the file (often user error)...

PS ah use 2 7/8 yo HDs as backups, never had problems...but then ah look after them...



If yer not seeing screens like these regularly...







Then it's highly unlikely that it's the HD, which leaves a software fault...

PPS tae set yer mind at rest run CHKDSK,( click "Start" - "My/This Computer" - right click on "C" drive - scroll down tae "Properties" - "Tools" - "Error Checking", It won't run right away, needs a restart, then it's automatic. It'll take anything from 30 mins tae a couple of hours, depending on the size and amount of stuff on yer HD.

[Bobobird]

I think it is necessary to chip in here - computer overheating can/will lead to very obvious issues - you WILL know that there is something wrong.

On the other hand, faulty components can and do overheat and will cause intermittent issues that are not obvious.

If the computer is operating fine generally and this is the only time this has happened then let the thing go. There is really no point fretting about it.

[Nicks Pics]

Thanks Manfred,

Thanks tao2,
Thanks for the advice on computers. If it is a hard drive issue, it would be my external hard drive. I'm not getting computer error notices- so that's good.

Thanks Bobobird

I'll keep a look out for more issues, but otherwise will let it go for now

[Manfred M]

A failing hard drive will exhibit many more problems than one line in one photo

Robert - a bad block is not necessarily a sign of a failing hard drive.

Hard drives (as with any mechanical device) are not perfect. During testing, the manufacturer will mark any bad blocks in a lookup table on the hard drive. The drive firmware will not use those bad blocks.

Some blocks are "marginal" and might just sneak under being identified as being "good" during the manufacturing test process. If they "go bad", these can be the cause of data errors. Software can identify them and add them to the lookup table so that they are no longer used.

A significant increase in the number of bad blocks can be indicative of a failing drive, but small numbers going bad over time is quite normal. I have seen data errors from this source in the past.

[tao2]

Robert - a bad block is not necessarily a sign of a failing hard drive.

Hard drives (as with any mechanical device) are not perfect. During testing, the manufacturer will mark any bad blocks in a lookup table on the hard drive. The drive firmware will not use those bad blocks.

Some blocks are "marginal" and might just sneak under being identified as being "good" during the manufacturing test process. If they "go bad", these can be the cause of data errors. Software can identify them and add them to the lookup table so that they are no longer used.

A significant increase in the number of bad blocks can be indicative of a failing drive, but small numbers going bad over time is quite normal. I have seen data errors from this source in the past.

Hi Manfred, if ye read my post again, ah didn't say, anywhere, that bad blocks (sectors) were a sign of failing HDs - ah said...

A failing hard drive will exhibit many more problems than one line in one photo - inexplicable shutdowns, a general slowing down of PC operations, frequent app and screen freezing, BSOD (blue screen of death).

In reference tae bad sectors - ah said (referring tae corrupted files)...

Files corrupted by bad sectors will...
a) Fail tae open
b) If able tae be opened will look like this (example 1), an extreme example but even small parts of a file like this will show that it's a corrupt file either from a bad sector or a fault when closing or saving the file (often user error)...

The reason ah suggested CHKDSK is that it'll try tae move data tae a good sector and that bad sector will be marked as "user found" and never used again. If yer lucky, most files can be recovered but often - not...