K4 Screensaver Hack

[thomass]

Originally Posted by LLM

Feel like a complete newbie leaching off you guys, but here goes again:

So, I got it all done, the folder (screensaver) was created, but when I put photos in it (pngs, b&w, 600*800) only the first one shows. (Don't know if the Kindle screen actually burns in, but that would be a screen burner, rather than a screen saver.) Any ideas why this might be?

Other random details which may or may not be relevant:

A "RUNME.done" and a "RUNME.out" file also appeared in the root directory of the Kindle. There is no " /opt/amazon/screen_saver/600x800_" folder with the original photos.

Thanks!

Could you upload the RUNME.out?
You can erase the RUNME.sh, RUNME.done and RUNME.out.
BTW: to able to see /opt/amazon/screen_saver/600x800_ , you should use usbnetworking.

[knc1]

Originally Posted by LLM

Feel like a complete newbie leaching off you guys, but here goes again:

So, I got it all done, the folder (screensaver) was created, but when I put photos in it (pngs, b&w, 600*800) only the first one shows.

No idea, will leave that one for someone who knows.

Originally Posted by LLM

(Don't know if the Kindle screen actually burns in, but that would be a screen burner, rather than a screen saver.) Any ideas why this might be?

It does not "burn in".
The relective pixels are actually "flipped over" to change from black to white.
The "pixel state" is static, no power required, pull the battery and a month later the screen still is displaying whatever it was displaying.

Originally Posted by LLM

Other random details which may or may not be relevant:

A "RUNME.done" and a "RUNME.out" file also appeared in the root directory of the Kindle. There is no " /opt/amazon/screen_saver/600x800_" folder with the original photos.

Thanks!

There may be a bit of misunderstanding at work here with the phrase "root directory" of the Kindle.

What you see from another machine connected via USB as the Kindle storage area is actually a sub-directory of the Kindle's "root directory" (/mnt/us).
I.E: only part of the file system tree is visible to the "normal" user unless some other type of access is in use (terminal over ssh, full file system export over OTG, etc.).

[geekmaster]

Originally Posted by LLM

(Don't know if the Kindle screen actually burns in, but that would be a screen burner, rather than a screen saver.)

There is no "burn in". It may appear so after the kindle has been stored for some time, or stored in a cool location, but this is "fixed" by doing mulitple "full flash clears". On the K5(touch), you can do two or three "eips -f -c" commands. On older kindles it is just "eips -c".

WHY eink burn-in cannot occur:

Spoiler:

Every pixel of the eink screen is made of many tiny beads. These beads are filled with oil. Inside this oil are many tiny particles that hold a permanent electric charge. Half of the particles hold a positive charge, and the other half hold a negative charge (depending on whether they are black or white particles). The eink screen has a grid of fine wires that control the electric field. When an electric field is applied to a pair of row and column wires, the electric field is much stronger at (and to a lesser degree, near) the intersection of the wires, and it causes the black and white charged particles to move to the front and back surfaces of the beads.

Because some particles near the intersection also move, there is a complex interaction that can cause ghosting artifacts. The eink uses a complex alternating current waverform to "shake" the particles in a way that gets them where they need to be. There are different waveforms for different temperatures, and different waverforms for different production runs of the eink screens (adapted to the statistical median characteristics of that batch of eink screens). Screens that are a "statistical outlier" (far from the mean waveform prototype for that batch, but within quality control limits), may have less contrast and more ghosting artifacts than screens closer to the statistical mean for that batch.

When the oil in the beads is at a temperature lower than the waveform can tolerate, the oil viscosity is increased, slowing down the colored charged particle movements. This can leave some particles behind, stuck to the bead surfaces, causing ghosting. If you wait for the oil to warm up (ideally to 25C/78F), then do multiple full flash clears, it will electrically "rip" the stuck particles from the bead surface, giving a cleaner looking display.

If you display an image on the eink, then remove the display from the kindle (and from the rigid protective backing plate behind it), you will see a silvery negative image on the back of the eink display. That is because wherever the black or white particles were pulled to the front, the oppositely colored (and oppositely charged) particles were pulled to the back.

So, the SHORT answer to your question is "NO, the display cannot burn-in", but to those who do not understand the technology, it can APPEAR that burn-in does occur.

[knc1]

Reads a lot like how core memory works, only with oil beads instead of ferrite cores.

[geekmaster]

Originally Posted by knc1

Reads a lot like how core memory works, only with oil beads instead of ferrite cores.

Also electric instead of magnetic fields, but the same idea. I still have some core-planes around here. One of them is mounted in a picture frame.

[knc1]

Originally Posted by geekmaster

Also electric instead of magnetic fields, but the same idea. I still have some core-planes around here. One of them is mounted in a picture frame.

Keep them.
There is an effort ongoing to bring back "core memory" only using nano-tube nickel (or other materials).
Nano-tube nickel just happens to look like 30w motor oil to the naked eye.
Once they figure out how to string the wires through the microscopic holes...

[geekmaster]

There seems to be a DIY core memory "hobby" now:
http://ocfnash.wordpress.com/2011/05...memory-reborn/

Here are the DIY core memory "shield" plans for your Arduino: http://www.corememoryshield.com/

To learn more about core memory, be sure to read the short PDF file at the second link above.

[reposed]

is there anyway to shuffle the screensavers on the K4?

[thomass]

Originally Posted by reposed

is there anyway to shuffle the screensavers on the K4?

not but you can create a renamer script and run it via kite

[reposed]

Originally Posted by thomass

not but you can create a renamer script and run it via kite

Please explain how.

[thomass]

Originally Posted by reposed

Please explain how.

• use google to learn how to batch rename files on linux
• first understand and then use the kite

it could be wrong but I assumed that it sorts the pictures according to their names. if this is the case then this method should work (at least after a restart) but it may be possible to make this work w/o a restart by using the already exist names(for example, some fix names like numbers etc)

[reposed]

Originally Posted by thomass

• use google to learn how to batch rename files on linux
• first understand and then use the kite

it could be wrong but I assumed that it sorts the pictures according to their names. if this is the case then this method should work (at least after a restart) but it may be possible to make this work w/o a restart by using the already exist names(for example, some fix names like numbers etc)

Okay, I can't figure this out. I've been reading blogs about how to rename files and can't understand it. Is there anyway you could make me one? I would be forever grateful...

[pretober]

Originally Posted by thomass

(NOT FOR KSO)

[LIST][*]there is no need for jailbreak. If you have a RUNME.done file on your kindle, you need to delete it.
...

Hi Thomass,
My kindle is with special offers. Now the screensaver is still special offers after I copy images (png format, b&w, 600x800) into that folder (All success). But don't know why, could you give me some tips or suggestion?
Thanks in advance,
Pretober

[thomass]

Originally Posted by pretober

Hi Thomass,
My kindle is with special offers. Now the screensaver is still special offers after I copy images (png format, b&w, 600x800) into that folder (All success). But don't know why, could you give me some tips or suggestion?
Thanks in advance,
Pretober

the very first line says that this process is not for KSO( Kindle with Special Offers) . Then this output is quite expected.

if you want to use this process, firstly you need to remove the ads .

[pretober]

Originally Posted by thomass

the very first line says that this process is not for KSO( Kindle with Special Offers) . Then this output is quite expected.

if you want to use this process, firstly you need to remove the ads .

Thanks for your quick reply. Sorry for inconvenience cause I don't know what does "KSO" means at first.

Then could you give a link how to remove the ads? So many threads here...

Great thanks, again.