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GeneralI See A Roomba-powered Tank in Your Future Pin
Gerry Schmitz31-May-21 21:38
mveGerry Schmitz31-May-21 21:38 
GeneralRe: I See A Roomba-powered Tank in Your Future Pin
SeanChupas1-Jun-21 1:59
MemberSeanChupas1-Jun-21 1:59 
GeneralRe: I See A Roomba-powered Tank in Your Future Pin
Daniel Pfeffer1-Jun-21 2:22
professionalDaniel Pfeffer1-Jun-21 2:22 
GeneralRe: I See A Roomba-powered Tank in Your Future Pin
dandy721-Jun-21 3:28
Memberdandy721-Jun-21 3:28 
GeneralRe: I See A Roomba-powered Tank in Your Future Pin
obermd1-Jun-21 6:38
Memberobermd1-Jun-21 6:38 
GeneralRe: I See A Roomba-powered Tank in Your Future Pin
obermd1-Jun-21 6:40
Memberobermd1-Jun-21 6:40 
GeneralRe: I See A Roomba-powered Tank in Your Future Pin
Mycroft Holmes1-Jun-21 13:16
professionalMycroft Holmes1-Jun-21 13:16 
GeneralCrouching Tiger, Hidden Complexity Pin
honey the codewitch31-May-21 18:59
mvahoney the codewitch31-May-21 18:59 
Something I run into a lot with IoT is things that seem simple become complicated quickly due to having to run in a constrained environment.

Take running a jpeg slideshow off an SD card on a 320kB system with a 320x240 display.

Wire up the SD and an ST7789 or ILI9341 and bob's your uncle, one might think.

Except for one small wrinkle - a camera produces images in the megapixel range. That display is only .0768 megapixels if my math is right.

That means you have to do some sort of resizing on most images. Well, it's all well and good to do bicubic or bilinear resampling of an image if you can access the entire uncompressed image data in a frame buffer, but again, a 320kB system. Good luck.

Images must be progressively loaded and then blted more or less directly to the display as it loads - since the display hardware has its own 320x240 display memory on the chip. How that happens depends on the underlying image format. For BMP files progressive loading means going from bottom to top, scanline by scanline. For JPEGS it means getting 8x8 squares of the image at a time, left to right, top to bottom, etc.

The issue here is when you're resampling you need to use matrix computations on *overlapping* regions of the image in order to get a proper result, meaning you can't just resize those 8x8 chunks to 6x6 for example and call it good. It would create artifacts every 6 pixels where it wasn't "blended" properly at the edges with the next pixel.

So suddenly you need something like maybe a 12x12 intermediary buffer so you can progressively resample, which makes a simple algorithm suddenly messy.

And this is just an example.

All this for a slideshow.
Real programmers use butterflies

GeneralRe: Crouching Tiger, Hidden Complexity Pin
Super Lloyd31-May-21 20:03
MemberSuper Lloyd31-May-21 20:03 
GeneralRe: Crouching Tiger, Hidden Complexity Pin
honey the codewitch31-May-21 20:28
mvahoney the codewitch31-May-21 20:28 
GeneralRe: Crouching Tiger, Hidden Complexity Pin
megaadam1-Jun-21 4:47
professionalmegaadam1-Jun-21 4:47 
GeneralRe: Crouching Tiger, Hidden Complexity Pin
honey the codewitch1-Jun-21 4:53
mvahoney the codewitch1-Jun-21 4:53 
QuestionRe: Crouching Tiger, Hidden Complexity Pin
megaadam1-Jun-21 5:21
professionalmegaadam1-Jun-21 5:21 
AnswerRe: Crouching Tiger, Hidden Complexity Pin
honey the codewitch1-Jun-21 5:32
mvahoney the codewitch1-Jun-21 5:32 
QuestionRe: Crouching Tiger, Hidden Complexity Pin
megaadam1-Jun-21 7:51
professionalmegaadam1-Jun-21 7:51 
AnswerRe: Crouching Tiger, Hidden Complexity Pin
honey the codewitch1-Jun-21 8:08
mvahoney the codewitch1-Jun-21 8:08 
GeneralSuggestions for Folder Viewer Pin
Richard Andrew x6431-May-21 11:50
professionalRichard Andrew x6431-May-21 11:50 
GeneralRe: Suggestions for Folder Viewer Pin
Mircea Neacsu31-May-21 12:09
mvaMircea Neacsu31-May-21 12:09 
GeneralRe: Suggestions for Folder Viewer Pin
Richard Andrew x6431-May-21 12:39
professionalRichard Andrew x6431-May-21 12:39 
GeneralRe: Suggestions for Folder Viewer Pin
Mircea Neacsu31-May-21 12:46
mvaMircea Neacsu31-May-21 12:46 
GeneralRe: Suggestions for Folder Viewer Pin
Richard Andrew x6431-May-21 12:51
professionalRichard Andrew x6431-May-21 12:51 
GeneralRe: Suggestions for Folder Viewer Pin
Mycroft Holmes31-May-21 12:11
professionalMycroft Holmes31-May-21 12:11 
GeneralRe: Suggestions for Folder Viewer Pin
Richard Andrew x6431-May-21 12:51
professionalRichard Andrew x6431-May-21 12:51 
GeneralRe: Suggestions for Folder Viewer Pin
Wendelius31-May-21 18:57
mveWendelius31-May-21 18:57 
GeneralRe: Suggestions for Folder Viewer Pin
Jörgen Andersson31-May-21 20:13
professionalJörgen Andersson31-May-21 20:13 

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