Hacks Kindle 4 nt screensavers

[EightWeight]

I have hacked my Kindle no-touch SO firmware 4.0.1 to display custom screensavers. I have found out a couple interesting things.

1) PNG and JPG is the only allowable format for screensavers.

2) Though certain guides for previous Kindles say that only indexed, 16 color, gray scale images can be used, I have been able to use color photos that render very well with at least 256 color palettes. Of course you won't see any color. Your mileage may vary.

3) I have only tried 600x800 images. I don't yet know if larger images will be cropped or scaled by the Kindle. [edit: appears it will center a larger image, cutting off the edges]

The mod procedure to get custom screens is described in other threads so I won't go into it here.

[eGod]

EightWeight,
As per my post in the Jailbreaking Kindle 4 thread I am using jpg greyscale images. The file names are not the same as the original names e.g. bob_600_800.jpg etc and these work fine when stored in the /mnt/base-mmc/opt/amazon/screen_saver/600x800 directory.

As for their names, the screensavers are shown in alphabetical order and I'll bet the marketing guys made them change the order and images multiple times, so instead of renaming all the files they simply renamed the filenames.

I'm pretty sure 08N.png was this:
... but that didn't last long

Cheers

[EightWeight]

There must be some difference between the SO and non-SO versions that makes jpg and random filenames unusable, although I can't think of what.

[eGod]

Perhap the case of the file type causes an issue i.e. jpg vs JPG?
All mine are lower case...

Cheers

[EightWeight]

Tried it both ways...no joy.

UPDATE: I have random filenames working!!! I read a post that suggested using ln -sfn instead of ln -s when creating the link to the screensaver directory in /mnt/us/. For some reason this works. I haven't tried jpgs or gifs yet.

[eGod]

And I have my screensavers working as well. I retried relinking through SSH the original 600x800 directory to the screensavers directory at the /us/mnt level and this time it has taken.

Enough with the jailbreaking ... time to get some content on it.

Cheers,
Paul

[damonlee]

Did anybody back up the original screen savers from the kindle 4?

I recently enabled custom screen savers but misplaced the originals.

Any help would be greatly received

[EightWeight]

Originally Posted by damonlee

Did anybody back up the original screen savers from the kindle 4?

http://dl.dropbox.com/u/41823/OH_NO/old_screensaver.rar

[nurusz]

hi
has somebody tried this tool ?
http://www.kubizo.com/chahttp://www....e-screensaver/
I have K4 NT and I'm afraid trying it

[EightWeight]

The tool works OK, but it's not really necessary. The K4 NT seems capable of resizing graphics all by itself, within limits. Nor does it really care what the color depth is, it will render gray scale just fine in my experience. I'm using both .png and .jpg files that are slightly bigger than 800x600 and in full color. Doesn't make any difference.

[nurusz]

Originally Posted by EightWeight

The tool works OK, but it's not really necessary. The K4 NT seems capable of resizing graphics all by itself, within limits. Nor does it really care what the color depth is, it will render gray scale just fine in my experience. I'm using both .png and .jpg files that are slightly bigger than 800x600 and in full color. Doesn't make any difference.

Thanks
After all I think that the main purpose of the K4 NT is reading books, so why to bother myself with screen savers ?!
For that kind of games I have my Android Tab

[EightWeight]

Originally Posted by nurusz

Thanks
After all I think that the main purpose of the K4 NT is reading books, so why to bother myself with screen savers ?!
For that kind of games I have my Android Tab

Reading books? How novel! Sorry.

I guess we do this stuff because we can. Same reason people customize their cars as a personal statement.

[degaba]

How did you do this hack? I have a kindle 4.01 wifi no touch and I'd like to do what you've done.