【迪文COF结构智能屏试用体验】1根串口数据线实现迪文屏高帧数无花屏无卡顿串口线视频流传输

https://v.superbed.cn/play/624f1986239250f7c5c522e3

334eba5c5033e0ec13ddbc4e19b0b1ee_raw

前言
相信大家看了顶部的演示视频之后，可能都会怀疑串口真的能否实现这种帧率的视频流实时传输，其实我一开始做的时候也在考虑是否要用C51内核驱动OV2640摄像头，还是说考虑用串口传输摄像头JPEG数据。结果就是串口传输完全不会输直接驱动。视频流的帧率可以稳定在10~17帧，并且几乎没有出现花屏和卡顿。
正文
想要实现视频中的效果，必须实现以下几点：
①使用两个图标叠加控件来回切换显示，如果只有1个图标叠加控件显示，那会在串口传输jpeg数据时出现图片刷新的过程，如视频所示https://v.superbed.cn/play/624f1986239250f7c5c522e3。所以使用两个图标叠加切换显示，可以隐藏正在刷新的图标叠加控件，同时显示另一个已经刷新完成的图标控件。
②两个图标叠加控件重合在一起，一个在顶层，一个在底层。底层的控件一定不要移动坐标隐藏，我们只需要移动顶层的控件来实现显示和隐藏。如果让两个控件交替显示和隐藏，在图片刷新速度很快的情况下，会闪烁出现背景图片，通过该文章的底部视频可以看到闪烁的现象。
③迪文CFG配置文件的波特率设置为3225600。没错！使用迪文的串口屏的最大波特率，这样能够明显的加快图片刷新的速度。迪文屏的串口能够在这么快的串口传输速度下很少受到干扰，并且能够很好的很快的处理接收的数据，这无疑体现了迪文屏的硬件强大之处。
④图片大小不能超过64kB，最好不要超过30kB，具体大小得看你分配给图标叠加控件的变量地址。如果超出图片大小就可能出现花屏和显示错误。
步骤一：
配置迪文控件，放图标叠加控件2(底层),描述地址为1200，变量地址为7FFE。放图标叠加控件1(顶层)，描述地址为1100，变量地址为1FFE。放数据变量显示控件，描述地址默认，变量地址为1000，用于显示FPS。配置CFG波特率。保存并生成工程文件，将背景图片生成icl。放入SD卡烧录。

步骤二：
了解迪文控件移动坐标的协议，我们将图标叠加控件移动到屏幕外的坐标即视为隐藏控件，移动回(0，0)坐标则回到控件原点显示图像。

步骤三：
了解迪文图标叠加控件的传输图像协议，并且注意，图中的的红线部分是“补齐”0x00和0x00直到迪文屏接收到240字节的图像数据，而不是在结尾添加0x00和0x00。

步骤四：
以下代码是烧录进入ESP32CAM摄像头模组的，用于获取视频流并将图像数据分包发送给迪文屏。以下代码包含串口图传、SD卡图传与上传图片至巴法云服务器,代码中只运行了串口图传，SD图传和上传图片至运动的代码写了但并没有运行到，无视这部分代码即可。如果感兴趣的可以看懂之后用SD卡进行图传。

#include
#include
#include
#include "ArduinoJson.h"
#include "esp_camera.h"
#include "esp_http_client.h"
#include "SD.h"
#include "FS.h"
#include
#include
#include "SD_MMC.h"
#include <time.h>
#include "string.h"
const char *uid = "填写私钥"; //用户私钥，巴法云控制台获取
const char *topic = "numberpic"; //主题名字，可在控制台新建
const char *post_url = "http://images.bemfa.com/upload/v1/upimages.php"; // 默认巴法云上传地址
static String httpResponseString; //接收服务器返回信息
int page = 0;
// 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
String comdata = ""; //缓存清零
HTTPClient http_client;
char data_json[40000];
String url1;
int fps = 0;
unsigned long previousMillis = 0; //毫秒时间记录
const long interval = 1000; //时间间隔
char path[] = "";
int num = 35;
void WiFi_Connect()
{
WiFi.begin("WIFI账号", "WIFI密码");
while (WiFi.status() != WL_CONNECTED)
{ //这里是阻塞程序，直到连接成功
delay(300);
Serial.print(".");
}
}
void sd_init()
{
if (!SD_MMC.begin())
{
Serial.println("Card Mount Failed");
return;
}
uint8_t cardType = SD_MMC.cardType();
if (cardType == CARD_NONE)
{
Serial.println("No SD card attached");
return;
}
Serial.print("SD Card Type: ");
if (cardType == CARD_MMC)
{
Serial.println("MMC");
}
else if (cardType == CARD_SD)
{
Serial.println("SDSC");
}
else if (cardType == CARD_SDHC)
{
Serial.println("SDHC");
}
else
{
Serial.println("UNKNOWN");
}
uint64_t cardSize = SD_MMC.cardSize() / (1024 * 1024); //获取SD卡大小，大小单位是MB
Serial.printf("SD 卡容量大小: %lluMBn", cardSize);
}
void num_to_path(void)
{
memset(path,'\0',strlen(path));
char str1[50];
strcat(path,"/video/pic");
itoa(num,str1,10);
strcat(path,str1);
strcat(path,".jpg");
//strcat(path1,path);
}
void setup()
{
Serial.begin(3225600); // open the serial port at 115200 bps;
delay(100);
Serial.print("Connecting.. ");
// WiFi_Connect();
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
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;
// init with high specs to pre-allocate larger buffers
if (psramFound())
{
config.frame_size = FRAMESIZE_VGA;
config.jpeg_quality = 28;
config.fb_count = 2;
}
else
{
config.frame_size = FRAMESIZE_SVGA;
config.jpeg_quality = 12;
config.fb_count = 1;
}
// 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;
}
else
{
Serial.println("Camera init successed.");
}
sd_init(); // SD卡初始化
}
/********http请求处理函数*********/
esp_err_t _http_event_handler(esp_http_client_event_t *evt)
{
if (evt->event_id == HTTP_EVENT_ON_DATA)
{
httpResponseString.concat((char *)evt->data);
}
return ESP_OK;
}
/********推送图片*********/
static esp_err_t take_send_photo()
{
Serial.println("Taking picture...");
camera_fb_t *fb = NULL;
esp_err_t res = ESP_OK;
fb = esp_camera_fb_get();
if (!fb)
{
Serial.println("Camera capture failed");
return ESP_FAIL;
}
fps++;
if (page == 0)
{
size_t jpg_size = fb->len;
Serial.println(jpg_size);
int packnum = 0;
packnum = jpg_size / 240;
char jpg_head_char[4] = {90, 165, 243, 130};
if (jpg_size % 240 != 0)
{
packnum = packnum + 1;
}
int jpg_add_num = 0x8000;
int j = 0;
int i = 0;
int jpg_trans = 0;
while (j < packnum)
{
Serial.write(jpg_head_char[0]);
Serial.write(jpg_head_char[1]);
Serial.write(jpg_head_char[2]);
Serial.write(jpg_head_char[3]);
if (j != 0)
{
jpg_add_num = jpg_add_num + 120; // 0x8000+0*0x78
}
// Serial.printf("j:%drn",j);
// Serial.printf("jpg_add_num:%drn",jpg_add_num);
Serial.write(jpg_add_num >> 8);
Serial.write(jpg_add_num);
i = j * 240; // 0,240
// Serial.printf("i:%drn",i);
jpg_trans = ((j + 1) * 240) - 1; //((0+1)*240)-1=239
// Serial.printf("jpg_trans:%drn",jpg_trans);
while (i <= jpg_trans) //发送[0]-[239]
{
Serial.write(fb->buf[i]);
if (fb->buf[i - 1] == 0xFF && fb->buf[i] == 0xD9)
{
break;
}
i++;
}
j++;
// delay(1);//10
}
if (jpg_size % 240 != 0)
{
int k = 0;
while (k < 240)
{
Serial.write(0);
k++;
}
}
// delay(5);
// delay(5000);
// char jpg_show[10]={90,165,7,130,127,254,90,165,128,0};
/*
Serial.write(90);
Serial.write(165);
Serial.write(7);
Serial.write(130);
Serial.write(127);
Serial.write(254);
Serial.write(90);
Serial.write(165);
Serial.write(128);
Serial.write(0);
*/
// delay(2000);
Serial.write(90);
Serial.write(165);
Serial.write(7);
Serial.write(130);
Serial.write(127);
Serial.write(254);
Serial.write(90);
Serial.write(165);
Serial.write(128);
Serial.write(0);
page = 1;
// delay(100);
//
int l = 0;
/*
Serial.write(90); //显示2
Serial.write(165);
Serial.write(7);
Serial.write(130);
Serial.write(18);
Serial.write(1);
Serial.write(0);
Serial.write(0);
Serial.write(0);
Serial.write(0);
l++;
*/
//
delay(10);
Serial.write(90); //隐藏1
Serial.write(165);
Serial.write(7);
Serial.write(130);
Serial.write(17);
Serial.write(1);
Serial.write(3);
Serial.write(32);
Serial.write(3);
Serial.write(32);
// delay(1000);
}
else
{
size_t jpg_size = fb->len;
Serial.println(jpg_size);
int packnum = 0;
packnum = jpg_size / 240;
char jpg_head_char[4] = {90, 165, 243, 130};
if (jpg_size % 240 != 0)
{
packnum = packnum + 1;
}
int jpg_add_num = 0x2000;
int j = 0;
int i = 0;
int jpg_trans = 0;
while (j < packnum)
{
Serial.write(jpg_head_char[0]);
Serial.write(jpg_head_char[1]);
Serial.write(jpg_head_char[2]);
Serial.write(jpg_head_char[3]);
if (j != 0)
{
jpg_add_num = jpg_add_num + 120; // 0x8000+0*0x78
}
// Serial.printf("j:%drn",j);
// Serial.printf("jpg_add_num:%drn",jpg_add_num);
Serial.write(jpg_add_num >> 8);
Serial.write(jpg_add_num);
i = j * 240; // 0,240
// Serial.printf("i:%drn",i);
jpg_trans = ((j + 1) * 240) - 1; //((0+1)*240)-1=239
// Serial.printf("jpg_trans:%drn",jpg_trans);
while (i <= jpg_trans) //发送[0]-[239]
{
Serial.write(fb->buf[i]);
if (fb->buf[i - 1] == 0xFF && fb->buf[i] == 0xD9)
{
break;
}
i++;
}
j++;
// delay(1);//10
}
if (jpg_size % 240 != 0)
{
int k = 0;
while (k < 240)
{
Serial.write(0);
k++;
}
}
// delay(2000);
Serial.write(90);
Serial.write(165);
Serial.write(7);
Serial.write(130);
Serial.write(31);
Serial.write(254);
Serial.write(90);
Serial.write(165);
Serial.write(32);
Serial.write(0);
page = 0;
// delay(100);
//
Serial.write(90); //显示1
Serial.write(165);
Serial.write(7);
Serial.write(130);
Serial.write(17);
Serial.write(1);
Serial.write(0);
Serial.write(0);
Serial.write(0);
Serial.write(0);
//
/*
Serial.write(90); //隐藏2
Serial.write(165);
Serial.write(7);
Serial.write(130);
Serial.write(18);
Serial.write(1);
Serial.write(3);
Serial.write(32);
Serial.write(3);
Serial.write(32);
*/
// delay(1000);
}
/*
//int i=0;
while(i
{
Serial.write(fb->buf[i]);
i++;
}*/
// Serial.print(fb->buf[0]);
/*
Serial.println("");
httpResponseString = "";
esp_http_client_handle_t http_client;
esp_http_client_config_t config_client = {0};
config_client.url = post_url;
config_client.event_handler = _http_event_handler;
config_client.method = HTTP_METHOD_POST;
http_client = esp_http_client_init(&config_client);
esp_http_client_set_post_field(http_client, (const char *)fb->buf, fb->len);//设置http发送的内容和长度
esp_http_client_set_header(http_client, "Content-Type", "image/jpg"); //设置http头部字段
esp_http_client_set_header(http_client, "Authorization", uid); //设置http头部字段
esp_http_client_set_header(http_client, "Authtopic", topic); //设置http头部字段
esp_err_t err = esp_http_client_perform(http_client);//发送http请求
if (err == ESP_OK) {
//json数据解析
StaticJsonDocument<200> doc;
DeserializationError error = deserializeJson(doc, httpResponseString);
if (error) {
Serial.print(F("deserializeJson() failed: "));
Serial.println(error.c_str());
}
String url = doc["url"];
url1=url;
Serial.println(url);//打印获取的URL
}
esp_http_client_cleanup(http_client);
*/
esp_camera_fb_return(fb);
}
static esp_err_t send_photo()
{
//将sd卡图片数据提取到fb中
camera_fb_t *fb = esp_camera_fb_get();
fb->len = 0;
*fb->buf = NULL;
Serial.println(*fb->buf);
fs::FS &fs = SD_MMC;
num_to_path(); //文件名组合数字+文件后缀
Serial.println(path);
if(num>0)
{
num--;
}else{
num=35;
}
File file = fs.open("/video/0.jpg", FILE_READ);//File file = fs.open(path, FILE_READ);
if (!file)
{
Serial.println("文件打开失败");
file.close();
}
else
{
fb->len = file.size(); //读取文件内大小
file.read(fb->buf, fb->len); //第一个参数是储存的buf，第二个是读取的信息长度
file.close();
Serial.println("成功读取照片");
fps++;
if (page == 0)
{
size_t jpg_size = fb->len;
Serial.println(jpg_size);
int packnum = 0;
packnum = jpg_size / 240;
char jpg_head_char[4] = {90, 165, 243, 130};
if (jpg_size % 240 != 0)
{
packnum = packnum + 1;
}
int jpg_add_num = 0x8000;
int j = 0;
int i = 0;
int jpg_trans = 0;
while (j < packnum)
{
Serial.write(jpg_head_char[0]);
Serial.write(jpg_head_char[1]);
Serial.write(jpg_head_char[2]);
Serial.write(jpg_head_char[3]);
if (j != 0)
{
jpg_add_num = jpg_add_num + 120; // 0x8000+0*0x78
}
// Serial.printf("j:%drn",j);
// Serial.printf("jpg_add_num:%drn",jpg_add_num);
Serial.write(jpg_add_num >> 8);
Serial.write(jpg_add_num);
i = j * 240; // 0,240
// Serial.printf("i:%drn",i);
jpg_trans = ((j + 1) * 240) - 1; //((0+1)*240)-1=239
// Serial.printf("jpg_trans:%drn",jpg_trans);
while (i <= jpg_trans) //发送[0]-[239]
{
Serial.write(fb->buf[i]);
if (fb->buf[i - 1] == 0xFF && fb->buf[i] == 0xD9)
{
break;
}
i++;
}
j++;
// delay(1);//10
}
if (jpg_size % 240 != 0)
{
int k = 0;
while (k < 240)
{
Serial.write(0);
k++;
}
}
Serial.write(90);
Serial.write(165);
Serial.write(7);
Serial.write(130);
Serial.write(127);
Serial.write(254);
Serial.write(90);
Serial.write(165);
Serial.write(128);
Serial.write(0);
page = 1;
int l = 0;
delay(10);
Serial.write(90); //隐藏1
Serial.write(165);
Serial.write(7);
Serial.write(130);
Serial.write(17);
Serial.write(1);
Serial.write(3);
Serial.write(32);
Serial.write(3);
Serial.write(32);
}
else
{
size_t jpg_size = fb->len;
Serial.println(jpg_size);
int packnum = 0;
packnum = jpg_size / 240;
char jpg_head_char[4] = {90, 165, 243, 130};
if (jpg_size % 240 != 0)
{
packnum = packnum + 1;
}
int jpg_add_num = 0x2000;
int j = 0;
int i = 0;
int jpg_trans = 0;
while (j < packnum)
{
Serial.write(jpg_head_char[0]);
Serial.write(jpg_head_char[1]);
Serial.write(jpg_head_char[2]);
Serial.write(jpg_head_char[3]);
if (j != 0)
{
jpg_add_num = jpg_add_num + 120; // 0x8000+0*0x78
}
Serial.write(jpg_add_num >> 8);
Serial.write(jpg_add_num);
i = j * 240; // 0,240
jpg_trans = ((j + 1) * 240) - 1; //((0+1)*240)-1=239
while (i <= jpg_trans) //发送[0]-[239]
{
Serial.write(fb->buf[i]);
if (fb->buf[i - 1] == 0xFF && fb->buf[i] == 0xD9)
{
break;
}
i++;
}
j++;
}
if (jpg_size % 240 != 0)
{
int k = 0;
while (k < 240)
{
Serial.write(0);
k++;
}
}
Serial.write(90);
Serial.write(165);
Serial.write(7);
Serial.write(130);
Serial.write(31);
Serial.write(254);
Serial.write(90);
Serial.write(165);
Serial.write(32);
Serial.write(0);
page = 0;
Serial.write(90); //显示1
Serial.write(165);
Serial.write(7);
Serial.write(130);
Serial.write(17);
Serial.write(1);
Serial.write(0);
Serial.write(0);
Serial.write(0);
Serial.write(0);
}
}
//清空数据
esp_camera_fb_return(fb);
}
// 获取粉丝数
void getPicNum()
{
memset(data_json, '\0', strlen(data_json)); //将数组清空
strcat(data_json, "{");
strcat(data_json, ""url":"https://s3.bmp.ovh/imgs/2022/02/51491c953c2345ba.jpg""); //
// strcat(data_json,""url":"");
// strcat(data_json,""");
// strcat(data_json,"}");
// Serial.println(data_json);
Serial.println("..........................");
int httpCode;
http_client.begin("https://aip.baidubce.com/rest/2.0/ocr/v1/numbers?access_token=24.596f1bb08a48ee2a26689169a483a1a7.2592000.1648374558.282335-25667508");
http_client.addHeader("Content-Type", "application/x-www-form-urlencoded");
httpCode = http_client.POST(url1); //("{"text":"food"}");
Serial.printf("Confirm URL:");
Serial.println(url1); //打印获取的URL1
if (httpCode > 0)
{
// httpCode will be negative on error
Serial.printf("HTTP Get Code: %drn", httpCode);
if (httpCode == HTTP_CODE_OK) // 收到正确的内容
{
String resBuff = http_client.getString();
Serial.println("Number recognition result:");
Serial.println(resBuff);
}
}
else
{
Serial.printf("HTTP Get Error: %sn", http_client.errorToString(httpCode).c_str());
}
http_client.end();
}
void loop()
{
take_send_photo();
//delay(3000);
//send_photo();
//num_to_path();
/*
if(num>0)
{
num--;
}else{
num=0;
}*/
//Serial.printf(path);
unsigned long currentMillis = millis(); //读取当前时间
if (currentMillis - previousMillis >= interval) //如果和前次时间大于等于时间间隔
{
previousMillis = currentMillis; //更新时间记录
// Serial.println(fps); //打印当前时间
Serial.write(90);
Serial.write(165);
Serial.write(5);
Serial.write(130);
Serial.write(16);
Serial.write(0);
if (fps <= 255)
{
Serial.write(0);
Serial.write(fps);
}
else
{
Serial.write(fps);
}
fps = 0;
}
// delay(5000);
// getPicNum();
// delay(10000);
}

复制代码

步骤五：
在编译烧写代码后，连接ESP32CAM和迪文屏之间的串口与电源，通电即可运行视频流效果。

494f09fde971ea457cb40623ccb1b5d7

龘龘_ · 2022-4-8 10:38:20

备注一下：顶部视频是最终成品视频效果，底部视频是关于底部控件切换会导致的结果

龘龘_ · 2022-4-8 10:52:12

https://www.bilibili.com/video/BV12g4y1B7Kz?share_source=copy_web这个链接是C51内核直接驱动OV2640的，这个视频里T5L迪文屏驱动200w像素的OV2640摄像头,输出的图片大小为320*240,帧率为14。文章里的视频流输出图片大小为640*480，帧率为10~17