Slika s microSD kartice

Što ovaj primjer prikazuje

Montirajte microSD karticu, ispišite njezine datoteke u ljusci i nacrtajte image.jpg s kartice uz dithering. Prije pokretanja kopirajte JPG u korijenski direktorij kartice pod nazivom image.jpg ili promijenite IMAGE_PATH. Na kraju se napajanje kartice isključuje.

Primjer koda

"""Initialize an SD card and render an image located on it."""

# Include needed libraries
from inkplate7spectra import Inkplate

from os import listdir, stat

# Create Inkplate object
inkplate = Inkplate()

# Initialize the display, needs to be called only once
inkplate.begin()

# Initializes the SD card.
#
# Parameters:
# - fastboot (bool, default=False):
#     If True, performs a soft reboot immediately after SD card initialization
#     (only on cold start or hard reset). This significantly improves SD card
#     read speeds—typically doubling performance.
#
# Note:
# - This function must be called before accessing files on the SD card.
# - The fastboot option has no effect if the device is already running.
inkplate.init_sd_card(fast_boot=True)

# This prints all the files on card
print(listdir("/sd"))


# Draw an image on the screen.
#
# Parameters:
# - path: File path to the image. Supports local paths (e.g., from SD card) or URLs.
#         Supported formats: JPG, PNG, BMP.
#
# - x0: X-coordinate of the top-left corner where the image will be displayed.
#
# - y0: Y-coordinate of the top-left corner where the image will be displayed.
#
# - invert (bool, default=False): If True, inverts the image colors.
#
# - dither (bool, default=False): If True, applies a dithering algorithm to
#   the image for better grayscale rendering.
#
# - kernel_type (int): Specifies the dithering algorithm to use.
#     Available options:
#       Inkplate.KERNEL_FLOYD_STEINBERG = 0
#       Inkplate.KERNEL_JJN             = 1
#       Inkplate.KERNEL_STUCKI          = 2
#       Inkplate.KERNEL_BURKES          = 3
#
# Performance Notes:
# - JPG: ~52 seconds (or ~90s with dithering)
#
# Example usage:
IMAGE_PATH = "sd/image.jpg"
try:
    stat(IMAGE_PATH)
except OSError:
    print("Image not found on SD card: {}".format(IMAGE_PATH))
    print("Copy an image to that path on the SD card, or change IMAGE_PATH above.")
else:
    inkplate.draw_image(
        IMAGE_PATH,
        0,
        0,
        invert=False,
        dither=True,
        kernel_type=Inkplate.KERNEL_FLOYD_STEINBERG,
    )

# Show the image from the buffer
inkplate.display()

inkplate.sd_card_sleep()
# To turn it back on, use:
# inkplate.sd_card_wake()

Korištene funkcije

Inkplate()returns Inkplate

Stvara objekt zaslona iz modula inkplate7spectra.

ReturnsObjekt zaslona.

inkplate.begin()returns bool

Postavlja pločicu i bijeli međuspremnik slike. Pozovite je jednom.

ReturnsTrue.

inkplate.init_sd_card(fast_boot=False)returns None

Uključuje napajanje kartice i montira karticu na /sd. S fast_boot=True nakon uključivanja napajanja, hardverskog ili watchdog reseta dodatno radi soft reset, za što primjer kaže da otprilike udvostručuje brzinu čitanja. Ako se kartica ne može pročitati, ispisuje 'Sd card could not be read'.

ReturnsNišta.

inkplate.draw_image(path, x0=0, y0=0, invert=False, dither=False, kernel_type=0)returns None

Crta BMP, JPG ili PNG sliku u međuspremnik slike. Putanja bez http:// ili https:// čita se kao lokalna datoteka, ovdje s kartice. Format se određuje prema ekstenziji datoteke.

ReturnsNišta. Nepodržana ekstenzija izaziva ValueError.

inkplate.display(leave_on=False)returns None

Šalje međuspremnik slike na panel i osvježava ga.

ReturnsNišta.

inkplate.sd_card_sleep()returns None

Isključuje napajanje kartice.

ReturnsNišta.

inkplate.sd_card_wake()returns None

Ponovno uključuje napajanje kartice nakon sd_card_sleep(). Primjer ga spominje samo u komentaru.

ReturnsNišta.

listdir() i stat() dolaze iz MicroPythonova modula os.

Što očekivati

Ljuska ispisuje popis datoteka na kartici. Ako je image.jpg na svom mjestu, zaslon se osvježi i prikaže sliku od gornjeg lijevog kuta. Bez nje ljuska ispisuje Image not found on SD card: sd/image.jpg i savjet da kopirate sliku, a zaslon se osvježi na bijelo.

🔗Otvorite cijeli primjer

examples/inkplate7spectra/displayimagesd/display_image_sd.py

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