Maker Eric Nam has constructed a low-power daylight-readable digital image body, powered by an Espressif ESP32-S3 microcontroller — however, in a twist, has opted for a seven-color ePaper show that delivers a protracted battery life with out having to drop all the way down to grayscale imagery.
“This shows picture knowledge on a 5.65″ seven-color ePaper [display],” Nam explains of his creation. “The advantage of the ePaper [display] is that it solely consumes energy when updating the display, and it will possibly maintain the present display even when the facility is lower off. That is why it is very advantageous to [use in] a battery-powered system.”
Electrophoretic ePaper shows, by which bodily globules of ink are moved in direction of or away from the higher layer of the display, are sunlight-readable, low-power, however have their downsides — together with a refresh price which is, at worst, measured in seconds-per-frame fairly than frames-per-second and the truth that the bulk available on the market are black and white. That is not the case for Nam’s chosen panel, a Seeed Studio 5.65″ show that delivers a seven-color palette — albeit at the price of a 22-second refresh time.
The show is pushed utilizing Seeed XIAO ESP32S3, a compact microcontroller board based mostly on the Espressif ESP32-S3. A Raspberry Pi working a Flask server transmits picture knowledge to the ESP32, which then places them on the display — after they’re resized to the show’s native decision and processed all the way down to seven colours. It is this final step that makes Nan’s show pop: utilizing Floyd-Steinberg dithering, the phantasm of extra colours is created and the standard of the photographs maintained.
There are only a few elements within the construct, although you will want a Flask server to retailer and transmit the pictures. (📷: Eric Nam)
“ePaper digital frames are very attention-grabbing,” Nam concludes. “I might wish to see sooner display refresh charges and extra colours displayed […] at an affordable worth.”
The undertaking is documented within the video above and on Nam’s YouTube channel, with extra data obtainable alongside the MIT licensed supply code on the undertaking’s GitHub repository.