K5 FW 5.x ScreenSavers Hack

[eschwartz]

Glad you have it working.
Cover mode FTW!

[GoSharks]

@anodyne-

To quote NiLuJe "usb cables are evil"
Glad it's sorted!

[yecam]

I have a Kindle PW2 with serial number starting with B0D4. Amazon blessed me with Firmware version 5.6.1 a while back but I was able to recover my screensaver hack with the aid of KUAL. However, even though the "last" mode and customized screensaver mode works I am unable to get the covers mode to work.

When I get things configured I can see a message flashing on the screen "Starting cover watchdog" but when I open a new book for the first time I see flashed on my screen after about 10 seconds the message "SW failed to extract cover" This is consistent on every book that I attempt to open, including older books where the cover mode used to work before the last Amazon firmware upgrade.

Assuming that I have properly formatted ebooks on my Kindle, what would trigger this error? I have tried downloading books directly from my Amazon Kindle account to the device and also after passing books through Calibre so I am pretty confident that I do not have any corrupted books. Would there be some component of the Python library that might be at fault? I have done refreshed installs of the latest Python and screensaver modules via KUAL but am now stumped.

[NiLuJe]

@yecam: Moved your post to the right thread (you originally posted in the K2/3/4 thread) .

If you recovered everything properly (JB hotfix, KUAL update, reinstall everything), I can't think of any reason why that would fail on FW 5.6.x.

Make sure you're using the latest snapshots, on the off-chance I fixed something and forgot about it ^^.

Barring that, having a look at some system logs might shed a modicum of light on the subject (enter ;dm in the Homescreen's searchbar, and PM me the log files that'll dump in documents/).

[NiLuJe]

@yecam: Hmm. ImageMagick is segfaulting. Which exact version of the ScreenSavers package are you using?

EDIT: To be more precise, it's segfaulting when building the personal info banner, which probably explains why nobody had complained so far (slightly obscure feature, that I only really test on a Touch anymore). I'll see if I can reproduce it . But barring that, is your personal info section containing anything funky looking (i.e. other than plain simple basic ASCII)?

That, and same question as before, the exact version/build/date of the ScreenSavers package you're using .

[yecam]

Here are the contents of the info.txt file in the screensaver directory.

$Id: info.txt 11165 2014-11-25 19:02:57Z NiLuJe $

Hello! If you're wondering what all this weird stuff on your Kindle is,
I'm a screen savers hack! There's a good chance that I came from here:
https://www.mobileread.com/forums/sho...d.php?t=195474

I'm at version 0.21.N, so, if you wish to uninstall me, you'll need the
uninstaller from that version, or from a newer one.

-- NiLuJe

The contents of my personal info file is pure ascii, basically just my name, phone number and email address. Just for giggles I cleared out the personal information and rebooted but the problem is still there.

[NiLuJe]

@yecam: I'll see if I can reproduce this tonight; in the mean time, check if it still happens with the latest snapshots .

[yecam]

I have it working with the latest snapshots from Feb 13, 2015. Yesterday I simply deleted my personal information using the regular Kindle menu and did not influence the erroneous cover behaviour. Just a few minutes ago I went into the KUAL/screen savers/Cover mode behaviour menu and disabled the personal info watermark. Now the cover mode is working.

Apparently the log file indicating a problem with personal information is flagging a real problem.

On a further note, I find that making changes to the screensaver behaviour with KUAL and then restarting the framework does not seem to put the changes into effect. I have been powering the Kindle down and then powering it up to get the changes to stick.

So what is the personal information watermark supposed to do? I was hoping that it would overwrite the displayed cover with my personal information if it was not broken.

[NiLuJe]

@yecam: Might need an X restart instead of a framework restart for some stuff to take.

And, yeah, the personal info watermark overlays a semi-transparent banner at the bottom of the cover w/ the personal info content.

That said, I can't reproduce this, either on a Touch, or a PW2 running 5.4.5.1, so, that's fairly strange...

EDIT: Scratch that, I have a fairly good inkling I'm not able to reproduce this because I'm using a custom freetype build. Double-checking. EDIT: Or not. Still can't reproduce with a vanilla FT. EDIT²: Or not². Reproduced with the vanilla FT build of FW 5.6.1. Victory \o/. Will be fixed in the next snapshots.

EDIT²: Also, the fact that the framework restart isn't enough for changes to take is an oversight on my part, that'll be fixed too.

[yecam]

If my observed problem with personal information is dependent on the version of the OS then I am wondering if Amazon enlarged the buffer devoted to the personal information or else inserted some weird end of message character. This might possibly make ImageMagick barf.

I tried varying the length of my personal information from zero bytes up to about 40 with no success. However, there appears to be a lot of space for my desired information, possibly more than what ImageMagick expects.

I am now a happy camper, knowing that I did not accidentally break anything while recovering from the Amazon OS upgrade.

Thanks

[NiLuJe]

@yecam: Nope, cf. my various edits, I figured it out . Amazon's weird FreeType build strikes again...

[NiLuJe]

I've just updated the snapshots, all those issues should now be resolved .

[yecam]

I installed the updated python and linkss packages via KUAL and can confirm that the framework restart in the KUAL menu now appears to work for getting screensaver changes to stick. There is now no need to recycle power to get the screensaver changes to stick.

However, I still see the original problem when I enable the personal information option in the covers behaviour menu. If I enable the feature I see a message about S W unable to extract the cover. When I disable the feature and do a framework restart then the cover mode works again.

Just to verify, the packages that I installed came from
kindle-linkss-0.22.N-r11537.tar and kindle-python-0.12.N-r11537.tar targeting the PW2/K5 flavour of Kindle

[NiLuJe]

@yecam: That's because I'm stupid, my bad .

Rename linkss/lib/libfreetype.so to linkss/lib/libfreetype.so.6 and that should do it .

[yecam]

@NiLuJe

That little fix corrected the brain fart problem Once I appended .6 to the library name and enabled the personal information option I was able to restart the framework and see my information in the banner at the bottom of the cover page when in sleep mode.

Corrected my original comments in the message as I figured out where I was going astray.

After looking at the source code for cover-extract I figured out why my personal information was being displayed in a very strange format. My personal information consisted of a short message starting with "If found, please return ......" The software in the code first looks for a file named pinfo.png in the cover_cache directory containing the personalized information and if it does not find it looks in the linkss base directory for a file named pinfo_header. If this is not found then the software generates the pinfo.png file by pre-pending the existing personal information with the following text: "If found, please contact:" Imagine my surprise when I started seeing this text repeated twice, once from the software generated logic and once from my original stored data.

The solution for me was to first simplify me stored personal data to just my name, email address and phone number. Then I manually deleted the pinfo.png file from the cover_cache directory and finally I performed a framework restart.

All is well now.

I never did find a file in the linkss base directory named pinfo_header. I believe that the design intention here is for the user to manually create this file if something other than the official KINDLE personal information is desired. Otherwise you get the official Kindle information pre-pended with a hard coded string as I have seen.

If my assumption is correct then we need this little gem documented. I am willing to generate the verbage but would first like to get the design intent confirmed. For me, things are now working but I would not have been able to figure this out without first looking at the source code.