Can't show Image with jpg format.

[HonestQiao]

My device: ESP32-S3-Box-Lite (N16R8V) + Display: ST7789
MycroPython: MicroPython v1.20.0-698-g3f25a765d on 2023-06-28; ESP32S3 Box Lite (spiram octal) with ESP32S3

My code:

import lvgl as lv
import lv_utils
import fs_driver

lv.init()
fs_drv = lv.fs_drv_t()
fs_driver.fs_register(fs_drv, 'S')

/* config for display */

scr = lv.scr_act()
cover_img = lv.img(scr)
cover_img.set_src("S:/images/zt_cover.png")
cover_img.set_size(180, 240)
cover_img.align(lv.ALIGN.TOP_LEFT, 0, 0)

If I use "S:/images/zt_cover.png" for cover_img.set_src(), the image will be displayed.

If I use "S:/images/zt_cover.jpg" for cover_img.set_src(), the image wont be displayed. No error, only empty.
zt_cover.jpg is convert from zt_cover.png.

I tried to use ./lib/lv_bindings/lvgl/scripts/jpg_to_sjpg.py to convert zt_cover.jpg to zt_cover.sjpg, but zt_cover.sjpg can't be displayed either.

In ./lib/lv_bindings/lv_conf.h, LV_USE_SJPG is open:

/*PNG decoder library*/
#define LV_USE_PNG 1

/*BMP decoder library*/
#define LV_USE_BMP 1

/* JPG + split JPG decoder library.
 * Split JPG is a custom format optimized for embedded systems. */
#define LV_USE_SJPG 1

/*GIF decoder library*/
#define LV_USE_GIF 1

What is the problem?

[amirgon]

I'm not sure it's related but ESP32S3 is not officially supported by lv_micropython.
Did you try to reproduce this problem in C? It's not clear to me if it's Micropython bindings issue of LVGL issue

[PGNetHun]

Hello!
There is a bug in LVGL lv_sjpg.c file, the problem is the color format:
lvgl/lvgl#4407 (comment)

[PGNetHun]

@amirgon ,
The JPEG color format issue will be fixed by PR lvgl/lvgl#4473
But please do not update LVGL library in binding yet, as there is another bug in JPEG rendering: lvgl/lvgl#4407 (comment)

the call to JPEG decoder is removed in the parallel rendering architecture commit:
lvgl/lvgl@f753265#diff-90f14ebcd1b2e071c69ef3ad4020cb675f2484b26db670b0e455b1aec6cabdb0L78