### Configuring WiFi and Display Settings (C)

Source: https://github.com/bitbank2/fastepd/blob/main/examples/esp_idf/www-image/README.md

C preprocessor directives defining WiFi credentials, display dimensions, and the default image URL for the example application. These settings are typically found in a settings.h file.

```C
// Edit the file: main/settings.h
// WiFi configuration
#define ESP_WIFI_SSID     "WIFI NAME"
#define ESP_WIFI_PASSWORD ""
// Add your display dimensions:
#define EPD_WIDTH 1200
#define EPD_HEIGHT 825
// This is then also used here:
#define IMG_URL "https://loremflickr.com/" STR(EPD_WIDTH) "/" STR(EPD_HEIGHT)
// You can of course point that IMG_URL to your own image source or service
```

--------------------------------

### Downloading JPEGDEC Submodule (Shell)

Source: https://github.com/bitbank2/fastepd/blob/main/examples/esp_idf/www-image/README.md

Command to initialize and update Git submodules, specifically for obtaining the Bitbank2 JPEGDEC component required for faster image decoding.

```bash
git submodule update --init --recursive
```

--------------------------------

### Setting Main Task Stack Size (Configuration)

Source: https://github.com/bitbank2/fastepd/blob/main/examples/esp_idf/www-image/README.md

Configuration setting for the ESP-IDF build system (Kconfig) to increase the main task stack size, which is necessary to prevent failures during TLS/SSL validation, particularly with embedTLS.

```Configuration
CONFIG_ESP_MAIN_TASK_STACK_SIZE=4584
```

--------------------------------

### Extracting SSL Certificate (Shell)

Source: https://github.com/bitbank2/fastepd/blob/main/examples/esp_idf/www-image/README.md

OpenSSL command used to connect to an HTTPS server and display its certificate chain, allowing extraction of the CA root certificate for embedding in the application binary for SSL verification.

```bash
openssl s_client -showcerts -connect www.loremflickr.com:443 </dev/null
```

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