Online screensaver extension - Page 10

workbee · Yesterday, 07:15 PM

Quote:

Originally Posted by FalconFour

Excellent win here... by the power of Claude Code ripping through the codebase and applying ideas and transformations, I managed to create a near-entirely-new version of this extension that takes a totally different approach. Instead of relying on complex internal timers and recovery techniques, we just ask the OS framework to do our bidding. Everything is now entirely based on events - device wakes? Update the image. Device is about to enter deep sleep? Set a future RTC wake time based on the scheduler. That's it.

By dramatically simplifying the code paths, I'm now on target for a full week of battery life on a charge, updating every 8 minutes during the day and 30 minutes at night. It hasn't missed a single update.

Check it out: https://github.com/FalconFour/onlinescreensaverPW2

I'll keep the Github repo updated with whatever new fixes I find it needs.

Thanks a lot for this, I've got it almost working and I hope you can help. So my Kindle (PW2 - 6th gen, DP75SDI) seems to be updating images from my server but it does distort them. When I update manually, or just put Kindle to sleep it looks good but just for a few seconds and then it distorts the image. When it updates itself from server it's distorted straight away and again when I put it to sleep it looks good just for a few seconds. I've attached photos of my test grid working and distorted (only horizontally).

I suspect it'll be something with resolution of my images? I've tried 758x1024 and 768x1024 px both with the same results. I did nothing special to images, just exported them out from Figma.

I'm nearly there, maybe I'm missing something?
Thanks!

FalconFour · Today, 01:32 AM

Oh, that's... interesting. The script just uses "eips" to update the image - info here: https://wiki.mobileread.com/wiki/Eips - syntax is "eips -f -g {imagefile}".

A fair bit has been said about the PNG format sent to the Kindle. The HA Kindle screensaver add-on (separate from my extension) has this to say:
https://github.com/sibbl/hass-lovela.../main/index.js - near the bottom, lines 302-326

It indicates the PNG output to be greyscale, bit depth 8 (that is actually somewhat unusual these days - creating a greyscale PNG specifically using 8-bit coding), with dithering and various other transformations that apply to the image, not the file format. With that, the missing piece may simply be to make it an 8-bit PNG, whereas most PNG output today is 24-bit color or higher.

Not sure if that's the whole problem, though. Rendering it twice is oddly suspicious, but one render could be coming from "linkss" rendering (which may be smarter), with a duplicate coming shortly behind it by the "eips" renderer called by the script.

If rendering it as an 8-bit PNG doesn't improve things, maybe upload an example file?

Also, unrelated - but I only noticed late in the game (while charging my Kindle for the week), that my newly improved extension will never update the screen while it's charging... it's entirely event-driven and focused on battery life above all else. It's better to cycle a battery than to keep it charging all the time anyway! (nervous laugh)... yeah, maybe I'll find a way to work "plugged-in" updates back into it in the future! It'd need to bring some self-timers back into the game, a bit ugly... but it might work.

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Today, 01:32 AM	#137
FalconFour Member Posts: 12 Karma: 10 Join Date: Mar 2018 Device: Kindle 7th Gen	Oh, that's... interesting. The script just uses "eips" to update the image - info here: https://wiki.mobileread.com/wiki/Eips - syntax is "eips -f -g {imagefile}". A fair bit has been said about the PNG format sent to the Kindle. The HA Kindle screensaver add-on (separate from my extension) has this to say: https://github.com/sibbl/hass-lovela.../main/index.js - near the bottom, lines 302-326 It indicates the PNG output to be greyscale, bit depth 8 (that is actually somewhat unusual these days - creating a greyscale PNG specifically using 8-bit coding), with dithering and various other transformations that apply to the image, not the file format. With that, the missing piece may simply be to make it an 8-bit PNG, whereas most PNG output today is 24-bit color or higher. Not sure if that's the whole problem, though. Rendering it twice is oddly suspicious, but one render could be coming from "linkss" rendering (which may be smarter), with a duplicate coming shortly behind it by the "eips" renderer called by the script. If rendering it as an 8-bit PNG doesn't improve things, maybe upload an example file? Also, unrelated - but I only noticed late in the game (while charging my Kindle for the week), that my newly improved extension will never update the screen while it's charging... it's entirely event-driven and focused on battery life above all else. It's better to cycle a battery than to keep it charging all the time anyway! (nervous laugh)... yeah, maybe I'll find a way to work "plugged-in" updates back into it in the future! It'd need to bring some self-timers back into the game, a bit ugly... but it might work.