我开始玩ESP32-CAM。 演示版Arduino camserver脚本与人脸识别等配合得很好。但是现在，我正在尝试实现一些有用的功能。
我知道here的示例设法在面部识别过程中以某种方式将文本叠加到视频提要上，但是我无法弄清楚如何在更简单的流式代码（如this）上实现此功能。
如何在此示例中进行文字叠加？
/*********
Rui Santos
Complete project details at https://RandomNerdTutorials.com
IMPORTANT!!!
- Select Board "ESP32 Wrover Module"
- Select the Partion Scheme "Huge APP (3MB No OTA)
- GPIO 0 must be connected to GND to upload a sketch
- After connecting GPIO 0 to GND, press the ESP32-CAM on-board RESET button to put your board in flashing mode
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files.
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
*********/
#include "esp_camera.h"
#include <WiFi.h>
#include "esp_timer.h"
#include "img_converters.h"
#include "Arduino.h"
#include "fb_gfx.h"
#include "soc/soc.h" //disable brownout problems
#include "soc/rtc_cntl_reg.h" //disable brownout problems
#include "dl_lib.h"
#include "esp_http_server.h"
//Replace with your network credentials
const char* ssid = "REPLACE_WITH_YOUR_SSID";
const char* password = "REPLACE_WITH_YOUR_PASSWORD";
#define PART_BOUNDARY "123456789000000000000987654321"
// This project was only tested with the AI Thinker Model
#define CAMERA_MODEL_AI_THINKER
// Not tested with these boards
//#define CAMERA_MODEL_M5STACK_PSRAM
//#define CAMERA_MODEL_WROVER_KIT
#if defined(CAMERA_MODEL_WROVER_KIT)
#define PWDN_GPIO_NUM -1
#define RESET_GPIO_NUM -1
#define XCLK_GPIO_NUM 21
#define SIOD_GPIO_NUM 26
#define SIOC_GPIO_NUM 27
#define Y9_GPIO_NUM 35
#define Y8_GPIO_NUM 34
#define Y7_GPIO_NUM 39
#define Y6_GPIO_NUM 36
#define Y5_GPIO_NUM 19
#define Y4_GPIO_NUM 18
#define Y3_GPIO_NUM 5
#define Y2_GPIO_NUM 4
#define VSYNC_GPIO_NUM 25
#define HREF_GPIO_NUM 23
#define PCLK_GPIO_NUM 22
#elif defined(CAMERA_MODEL_M5STACK_PSRAM)
#define PWDN_GPIO_NUM -1
#define RESET_GPIO_NUM 15
#define XCLK_GPIO_NUM 27
#define SIOD_GPIO_NUM 25
#define SIOC_GPIO_NUM 23
#define Y9_GPIO_NUM 19
#define Y8_GPIO_NUM 36
#define Y7_GPIO_NUM 18
#define Y6_GPIO_NUM 39
#define Y5_GPIO_NUM 5
#define Y4_GPIO_NUM 34
#define Y3_GPIO_NUM 35
#define Y2_GPIO_NUM 32
#define VSYNC_GPIO_NUM 22
#define HREF_GPIO_NUM 26
#define PCLK_GPIO_NUM 21
#elif defined(CAMERA_MODEL_AI_THINKER)
#define PWDN_GPIO_NUM 32
#define RESET_GPIO_NUM -1
#define XCLK_GPIO_NUM 0
#define SIOD_GPIO_NUM 26
#define SIOC_GPIO_NUM 27
#define Y9_GPIO_NUM 35
#define Y8_GPIO_NUM 34
#define Y7_GPIO_NUM 39
#define Y6_GPIO_NUM 36
#define Y5_GPIO_NUM 21
#define Y4_GPIO_NUM 19
#define Y3_GPIO_NUM 18
#define Y2_GPIO_NUM 5
#define VSYNC_GPIO_NUM 25
#define HREF_GPIO_NUM 23
#define PCLK_GPIO_NUM 22
#else
#error "Camera model not selected"
#endif
static const char* _STREAM_CONTENT_TYPE = "multipart/x-mixed-replace;boundary=" PART_BOUNDARY;
static const char* _STREAM_BOUNDARY = "\r\n--" PART_BOUNDARY "\r\n";
static const char* _STREAM_PART = "Content-Type: image/jpeg\r\nContent-Length: %u\r\n\r\n";
httpd_handle_t stream_httpd = NULL;
static esp_err_t stream_handler(httpd_req_t *req){
camera_fb_t * fb = NULL;
esp_err_t res = ESP_OK;
size_t _jpg_buf_len = 0;
uint8_t * _jpg_buf = NULL;
char * part_buf[64];
res = httpd_resp_set_type(req, _STREAM_CONTENT_TYPE);
if(res != ESP_OK){
return res;
}
while(true){
fb = esp_camera_fb_get();
if (!fb) {
Serial.println("Camera capture failed");
res = ESP_FAIL;
} else {
if(fb->width > 400){
if(fb->format != PIXFORMAT_JPEG){
bool jpeg_converted = frame2jpg(fb, 80, &_jpg_buf, &_jpg_buf_len);
esp_camera_fb_return(fb);
fb = NULL;
if(!jpeg_converted){
Serial.println("JPEG compression failed");
res = ESP_FAIL;
}
} else {
_jpg_buf_len = fb->len;
_jpg_buf = fb->buf;
}
}
}
if(res == ESP_OK){
size_t hlen = snprintf((char *)part_buf, 64, _STREAM_PART, _jpg_buf_len);
res = httpd_resp_send_chunk(req, (const char *)part_buf, hlen);
}
if(res == ESP_OK){
res = httpd_resp_send_chunk(req, (const char *)_jpg_buf, _jpg_buf_len);
}
if(res == ESP_OK){
res = httpd_resp_send_chunk(req, _STREAM_BOUNDARY, strlen(_STREAM_BOUNDARY));
}
if(fb){
esp_camera_fb_return(fb);
fb = NULL;
_jpg_buf = NULL;
} else if(_jpg_buf){
free(_jpg_buf);
_jpg_buf = NULL;
}
if(res != ESP_OK){
break;
}
//Serial.printf("MJPG: %uB\n",(uint32_t)(_jpg_buf_len));
}
return res;
}
void startCameraServer(){
httpd_config_t config = HTTPD_DEFAULT_CONFIG();
config.server_port = 80;
httpd_uri_t index_uri = {
.uri = "/",
.method = HTTP_GET,
.handler = stream_handler,
.user_ctx = NULL
};
//Serial.printf("Starting web server on port: '%d'\n", config.server_port);
if (httpd_start(&stream_httpd, &config) == ESP_OK) {
httpd_register_uri_handler(stream_httpd, &index_uri);
}
}
void setup() {
WRITE_PERI_REG(RTC_CNTL_BROWN_OUT_REG, 0); //disable brownout detector
Serial.begin(115200);
Serial.setDebugOutput(false);
camera_config_t config;
config.ledc_channel = LEDC_CHANNEL_0;
config.ledc_timer = LEDC_TIMER_0;
config.pin_d0 = Y2_GPIO_NUM;
config.pin_d1 = Y3_GPIO_NUM;
config.pin_d2 = Y4_GPIO_NUM;
config.pin_d3 = Y5_GPIO_NUM;
config.pin_d4 = Y6_GPIO_NUM;
config.pin_d5 = Y7_GPIO_NUM;
config.pin_d6 = Y8_GPIO_NUM;
config.pin_d7 = Y9_GPIO_NUM;
config.pin_xclk = XCLK_GPIO_NUM;
config.pin_pclk = PCLK_GPIO_NUM;
config.pin_vsync = VSYNC_GPIO_NUM;
config.pin_href = HREF_GPIO_NUM;
config.pin_sscb_sda = SIOD_GPIO_NUM;
config.pin_sscb_scl = SIOC_GPIO_NUM;
config.pin_pwdn = PWDN_GPIO_NUM;
config.pin_reset = RESET_GPIO_NUM;
config.xclk_freq_hz = 20000000;
config.pixel_format = PIXFORMAT_JPEG;
config.frame_size = FRAMESIZE_UXGA;
config.jpeg_quality = 10;
config.fb_count = 2;
// Camera init
esp_err_t err = esp_camera_init(&config);
if (err != ESP_OK) {
Serial.printf("Camera init failed with error 0x%x", err);
return;
}
// Wi-Fi connection
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
// Start streaming web server
startCameraServer();
Serial.print("Camera Stream Ready! Go to: http://");
Serial.print(WiFi.localIP());
}
void loop() {
delay(1);
}
答案 0 :(得分：0)
您可以查看CameraWebServer示例，尤其是文件app_httpd.cpp。我没有在下面测试代码，但我只是想展示这个想法。从示例中读取整个stream_handler函数，一切都会清楚。
您应该更改
bool jpeg_converted = frame2jpg(fb, 80, &_jpg_buf, &_jpg_buf_len);
到
dl_matrix3du_t *image_matrix = dl_matrix3du_alloc(1, fb->width, fb->height, 3);
fmt2rgb888(fb->buf, fb->len, fb->format, image_matrix->item);
// HERE print some text
rgb_print(image_matrix, 0x000000FF, "Hello!");
bool jpeg_converted = fmt2jpg(image_matrix->item, fb->width*fb->height*3, fb->width, fb->height, PIXFORMAT_RGB888, 90, &_jpg_buf, &_jpg_buf_len);
dl_matrix3du_free(image_matrix);
还有打印功能（同样来自app_httpd.cpp文件）
static void rgb_print(dl_matrix3du_t *image_matrix, uint32_t color, const char * str){
fb_data_t fb;
fb.width = image_matrix->w;
fb.height = image_matrix->h;
fb.data = image_matrix->item;
fb.bytes_per_pixel = 3;
fb.format = FB_BGR888;
fb_gfx_print(&fb, (fb.width - (strlen(str) * 14)) / 2, 10, color, str);
}
答案 1 :(得分：0)
我知道可能已经晚了，但是您可以轻松在图像上打印文本。
典型过程如下：
1-从相机获取图像：
camera_fb_t *fb = esp_camera_fb_get();
2-获取图像矩阵：
dl_matrix3du_t *image_matrix = dl_matrix3du_alloc(1, fb->width, fb->height, 3);
3-更改存储在image_matrix中的图像的格式：
fmt2rgb888(fb->buf, fb->len, fb->format, image_matrix->item);
4-在该矩阵上打印您选择的文本（FF为红色，您可以使用任何uint32_t。此外，请查看@ sashok1337响应中发布的rgb_print函数；您可以对其进行修改以发送其位置字符串）：
rgb_print(image_matrix, 0x000000FF, "test");
4-定义一个缓冲区并将矩阵转换为jpg（您可以在此处使用设置进行播放）：
size_t _jpg_buf_len = 0;
uint8_t * _jpg_buf = NULL;
bool jpeg_converted = fmt2jpg(image_matrix->item, fb->width*fb->height*3, fb->width, fb->height, PIXFORMAT_RGB888, 90, &_jpg_buf, &_jpg_buf_len);
上面带有文本的“框架”将存储在_jpg_buf数组中，您可以随时发送或存储它。