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I found it out.
For some reason png and jpg expect the buffer as BGR (and not RGB). I do not understand why, but it is what it is :slight_smile:

I wrote a small function converting RGB to BGR and then saving the new buffer.

void convertRGBtoBGR(uint8_t* buffer, uint32_t width, uint32_t height) {
    uint32_t totalPixels = width * height;
    for (uint32_t i = 0; i < totalPixels; ++i) {
        uint32_t index = i * 3;
        uint8_t r = buffer[index];       // R
        uint8_t g = buffer[index + 1];   // G
        uint8_t b = buffer[index + 2];   // B
        
        buffer[index] = b;               // B
        buffer[index + 1] = g;           // G
        buffer[index + 2] = r;           // R
    }
}

I am calling it like this:

            lv_draw_buf_t *buff = lv_screenshot_take(lv_disp_get_default(), LV_COLOR_FORMAT_RGB888);
            save_as_bmp_file(buff->data, buff->header.w, buff->header.h, 24, "A:/Users/ph/Downloads/test.bmp");
            
            convertRGBtoBGR(buff->data, buff->header.w, buff->header.h);
            save_as_png_file(buff->data, buff->header.w, buff->header.h, 24, "A:/Users/ph/Downloads/test.png");
            tje_encode_to_file("A:/Users/ph/Downloads/test.jpg", buff->header.w, buff->header.h, 3, buff->data);

Thanks for your help! :+1:

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