esp-idf/examples/common_components/qrcode/include/qrcode.h

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// Copyright 2020 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#pragma once
#include <esp_err.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief QR Code handle used by the display function
*/
typedef const uint8_t * esp_qrcode_handle_t;
/**
* @brief QR Code configuration options
*/
typedef struct {
void (*display_func)(esp_qrcode_handle_t qrcode); /**< Function called for displaying the QR Code after encoding is complete */
int max_qrcode_version; /**< Max QR Code Version to be used. Range: 2 - 40 */
int qrcode_ecc_level; /**< Error Correction Level for QR Code */
} esp_qrcode_config_t;
/**
* @brief Error Correction Level in a QR Code Symbol
*/
enum {
ESP_QRCODE_ECC_LOW, /**< QR Code Error Tolerance of 7% */
ESP_QRCODE_ECC_MED, /**< QR Code Error Tolerance of 15% */
ESP_QRCODE_ECC_QUART, /**< QR Code Error Tolerance of 25% */
ESP_QRCODE_ECC_HIGH /**< QR Code Error Tolerance of 30% */
};
/**
* @brief Encodes the given string into a QR Code and calls the display function
*
* @attention 1. Can successfully encode a UTF-8 string of up to 2953 bytes or an alphanumeric
* string of up to 4296 characters or any digit string of up to 7089 characters
*
* @param cfg Configuration used for QR Code encoding.
* @param text String to encode into a QR Code.
*
* @return
* - ESP_OK: succeed
* - ESP_FAIL: Failed to encode string into a QR Code
* - ESP_ERR_NO_MEM: Failed to allocate buffer for given max_qrcode_version
*/
esp_err_t esp_qrcode_generate(esp_qrcode_config_t *cfg, const char *text);
/**
* @brief Displays QR Code on the console
*
* @param qrcode QR Code handle used by the display function.
*/
void esp_qrcode_print_console(esp_qrcode_handle_t qrcode);
/**
* @brief Returns the side length of the given QR Code
*
* @param qrcode QR Code handle used by the display function.
*
* @return
* - val[21, 177]: Side length of QR Code
*/
int esp_qrcode_get_size(esp_qrcode_handle_t qrcode);
/**
* @brief Returns the Pixel value for the given coordinates
* False indicates White and True indicates Black
*
* @attention 1. Coordinates for top left corner are (x=0, y=0)
* @attention 2. For out of bound coordinates false (White) is returned
*
* @param qrcode QR Code handle used by the display function.
* @param x X-Coordinate of QR Code module
* @param y Y-Coordinate of QR Code module
*
* @return
* - true: (x, y) Pixel is Black
* - false: (x, y) Pixel is White
*/
bool esp_qrcode_get_module(esp_qrcode_handle_t qrcode, int x, int y);
#define ESP_QRCODE_CONFIG_DEFAULT() (esp_qrcode_config_t) { \
.display_func = esp_qrcode_print_console, \
.max_qrcode_version = 10, \
.qrcode_ecc_level = ESP_QRCODE_ECC_LOW, \
}
#ifdef __cplusplus
}
#endif