Update ESP32cam-demo.ino

ESP32cam-demo.ino

@@ -11,6 +11,7 @@
 *        flash led is still available for use (pin 4) and does not flash when accessing sd card
 *        Stores image in Spiffs if no sd card present
 *        PWM control of the illumination/flash LED
+*        Shows how to read the raw image data (greyscale and RGB)
 *
 *     GPIO:
 *        You can use io pins 13 and 12 for input or output (but 12 must not be high at boot)
@@ -58,29 +59,29 @@
 
     #include <Arduino.h>
 
-    // forward declarations
-      bool initialiseCamera(bool);
-      bool cameraImageSettings();
-      void changeResolution(framesize_t);
-      String localTime();
-      void flashLED(int);
-      byte storeImage();
-      void handleRoot();
-      void handlePhoto();
-      bool handleImg();
-      void handleNotFound();
-      void readRGBImage();
-      bool getNTPtime(int);
-      bool handleJPG(); 
-      void handleJpeg();
-      void handleStream();
-      int requestWebPage(String*, String*, int);
-      void handleTest();
-      void brightLed(byte);
-      void setupFlashPWM();
-      void handleData();
-      void readGreyscaleImage();
-      void resize_esp32cam_image_buffer(uint8_t*, int, int, uint8_t*, int, int);
+    // forward declarations (this is a list of all procedures in this sketch which Platform IO requires)
+      bool initialiseCamera(bool);            // this sets up and enables the camera (if bool=1 standard settings are applied but 0 allows you to apply custom settings)
+      bool cameraImageSettings();             // this applies the image settings to the camera (brightness etc.)
+      void changeResolution(framesize_t);     // this changes the capture frame size
+      String localTime();                     // returns the current time as a String
+      void flashLED(int);                     // flashes the onboard indicator led
+      byte storeImage();                      // stores an image in Spiffs or SD card
+      void handleRoot();                      // the root web page
+      void handlePhoto();                     // web page to capture an image from camera and save to spiffs or sd card
+      bool handleImg();                       // Display a previously stored image 
+      void handleNotFound();                  // if invalid web page is requested
+      void readRGBImage();                    // demo capturing an image and reading its raw RGB data
+      bool getNTPtime(int);                   // handle the NTP real time clock
+      bool handleJPG();                       // display a raw jpg image
+      void handleJpeg();                      // display a raw jpg image which periodically refreshes
+      void handleStream();                    // stream live video (note: this can get the camera very hot)
+      int requestWebPage(String*, String*, int);  // procedure allowing the sketch to read a web page its self
+      void handleTest();                      // test procedure for experimenting with bits of code etc.
+      void brightLed(byte);                   // turn the onboard flash LED on/off with varying brightness
+      void setupFlashPWM();                   // set up the PWM for the above flash
+      void handleData();                      // the root web page requests this periodically via Javascript in order to display updating information
+      void readGreyscaleImage();              // demo capturing a greyscale image and reading its raw RGB data
+      void resize_esp32cam_image_buffer(uint8_t*, int, int, uint8_t*, int, int);    // this resizes a captured greyscale image (used by above)
 
 
 // ---------------------------------------------------------------
@@ -88,7 +89,7 @@
 // ---------------------------------------------------------------
 
  char* stitle = "ESP32Cam-demo";                        // title of this sketch
- char* sversion = "15oct23";                            // Sketch version
+ char* sversion = "16oct23";                            // Sketch version
 
  bool sendRGBfile = 0;                                  // if set '/rgb' will just return raw rgb data which can be saved as a file rather than display a HTML pag
 
@@ -100,8 +101,9 @@
  #define useMCP23017 0                                  // set if MCP23017 IO expander chip is being used (on pins 12 and 13)
 
  // Camera related
-   bool flashRequired = 1;                              // If flash to be used when capturing image (1 = yes)
-   framesize_t FRAME_SIZE_IMAGE = FRAMESIZE_SVGA;       // Image resolution:
+   bool flashRequired = 0;                              // If flash to be used when capturing image (1 = yes)
+   const framesize_t cyclingRes[] = { FRAMESIZE_SVGA, FRAMESIZE_XGA, FRAMESIZE_SXGA, FRAMESIZE_QVGA, FRAMESIZE_VGA };    // resolutions to use
+                                                        // Image resolutions available:
                                                         //               default = "const framesize_t FRAME_SIZE_IMAGE = FRAMESIZE_VGA"
                                                         //               160x120 (QQVGA), 128x160 (QQVGA2), 176x144 (QCIF), 240x176 (HQVGA),
                                                         //               320x240 (QVGA), 400x296 (CIF), 640x480 (VGA, default), 800x600 (SVGA),
@@ -155,6 +157,7 @@
 
 //#include "esp_camera.h"         // https://github.com/espressif/esp32-camera
 // #include "camera_pins.h"
+framesize_t FRAME_SIZE_IMAGE = cyclingRes[0];
 #include <WString.h>            // this is required for base64.h otherwise get errors with esp32 core 1.0.6 - jan23
 #include <base64.h>             // for encoding buffer to display image on page
 #include <WiFi.h>
@@ -663,21 +666,23 @@ void resetCamera(bool type = 0) {
 // ----------------------------------------------------------------
 //                    -change image resolution
 // ----------------------------------------------------------------
-// if required resolution not supplied it cycles through several
+// cycles through the available resolutions (set in cyclingRes[])
 //Note: there seems to be an issue with 1024x768 with later releases of esp software?
-void changeResolution(framesize_t tRes = FRAMESIZE_96X96) {
+// Resolutions:  160x120 (QQVGA), 128x160 (QQVGA2), 176x144 (QCIF), 240x176 (HQVGA),
+//               320x240 (QVGA), 400x296 (CIF), 640x480 (VGA, default), 800x600 (SVGA),
+//               1024x768 (XGA), 1280x1024 (SXGA), 1600x1200 (UXGA)
+void changeResolution() {
+  //  const framesize_t cyclingRes[] = { FRAMESIZE_QVGA, FRAMESIZE_VGA, FRAMESIZE_SVGA, FRAMESIZE_XGA, FRAMESIZE_SXGA };    // resolutions to cycle through
+  const int noAvail = sizeof(cyclingRes) / sizeof(cyclingRes[0]);
+  static int currentRes = 0;  
   esp_camera_deinit();     // disable camera
-  delay(50);
-  if (tRes == FRAMESIZE_96X96) {      // taken as none supplied so cycle through several
-    if (FRAME_SIZE_IMAGE == FRAMESIZE_QVGA) tRes = FRAMESIZE_VGA;
-    else if (FRAME_SIZE_IMAGE == FRAMESIZE_VGA) tRes = FRAMESIZE_SVGA;
-    else if (FRAME_SIZE_IMAGE == FRAMESIZE_SVGA) tRes = FRAMESIZE_SXGA;
-    else tRes = FRAMESIZE_QVGA;
-  }
-  FRAME_SIZE_IMAGE = tRes;
+  delay(200);
+  currentRes++;                               // change to next resolution available
+  if (currentRes >= noAvail) currentRes=0;    // reset loop
+  FRAME_SIZE_IMAGE = cyclingRes[currentRes];
 
   initialiseCamera(1);
-  if (serialDebug) Serial.println("Camera resolution changed to " + String(tRes));
+  if (serialDebug) Serial.println("Camera resolution changed to " + String(cyclingRes[currentRes]));
   ImageResDetails = "Unknown";   // set next time image captured
 }
 
@@ -942,11 +947,14 @@ void handleRoot() {
 
    // links to the other pages available
      client.write("<br><br>LINKS: \n");
-     client.write("<a href='/photo'>Capture an image</a> - \n");
+     client.write("<a href='/photo'>Store image</a> - \n");
      client.write("<a href='/img'>View stored image</a> - \n");
-     client.write("<a href='/rgb'>Capture frame and display as RGB data</a> - \n");
-     client.write("<a href='/greydata'>Capture Greyscale frame as data</a> - \n");
+     client.write("<a href='/rgb'>RGB frame as data</a> - \n");
+     client.write("<a href='/greydata'>Greyscale frame as data</a> \n");
+     client.write("<br>");
      client.write("<a href='/stream'>Live stream</a> - \n");
+     client.write("<a href='/jpg'>JPG</a> - \n");
+     client.write("<a href='/jpeg'>Updating JPG</a> - \n");
      client.write("<a href='/test'>Test procedure</a>\n");
 
     // addnl info if sd card present
@@ -1538,6 +1546,7 @@ void handleJpeg() {
 // ----------------------------------------------------------------
 //                     resize greyscale image
 // ----------------------------------------------------------------
+// Thanks to Bard A.I. for writing this for me ;-)
 //   src_buf: The source image buffer.
 //   src_width: The width of the source image buffer.
 //   src_height: The height of the source image buffer.
@@ -1575,14 +1584,14 @@ void readGreyscaleImage() {
 
   WiFiClient client = server.client();                 // open link with client
 
- // html header
+  // html header
    sendHeader(client, "Access greyscale image data");  
 
-  // change camera to greyscale mode  (as by default it is in JPG colour mode)
+  // change camera to greyscale mode  (by default it is in JPG colour mode)
     esp_camera_deinit();                           // disable camera
     delay(50);
     config.pixel_format = PIXFORMAT_GRAYSCALE;     // change camera setting to greyscale (default is JPG)
-    initialiseCamera(0);                           // restart the camera without resetting the camera settings
+    initialiseCamera(0);                           // restart the camera (0 = without resetting all the other camera settings)
 
   // capture the image and use flash if required
     int currentBrightness = brightLEDbrightness;
@@ -1606,24 +1615,23 @@ void readGreyscaleImage() {
         avrg += fb->buf[(y * fb->width) + x];
       }
     }
-    client.println("<br>Greyscale Image: The average brightness of the " + String(dataSize) + " pixels is " + String(avrg / dataSize));
+    client.println("Greyscale Image: The average brightness of the " + String(dataSize) + " pixels is " + String(avrg / dataSize));
     client.write("<br><br><a href='/'>Return</a>\n");       // link back    
 
-  // resize image
-    int newWidth = 64;   int newHeight = 32;
+  // resize the image
+    int newWidth = 100;   int newHeight = 36;
     byte newBuf[newWidth * newHeight];
     resize_esp32cam_image_buffer(fb->buf, fb->width, fb->height, newBuf, newWidth, newHeight);
 
-  // display image
-    char asciiArt[] = {'@','#','+','!',':','.',' '};       // dark to light characters
-    const int noAsciiChars = 7;                                // number of characters
-    client.write("<br><pre>");
-
+  // display image as asciiArt
+    char asciiArt[] = {' ','.',',',':',';','+','*','?','%','S','#','@'};   // characters to use (light to dark)
+    int noAsciiChars = sizeof(asciiArt) / sizeof(asciiArt[0]);             // number of characters available
+    client.write("<br><pre>");                                             // 'pre' stops variable character spacing
     for (int y=0; y < newHeight; y++) {
-      client.write("</pre><pre>");
+      client.write("</pre><pre style='line-height: 0.2;'>");               // 'line-heigh' adjusts spacing between lines
       for (int x=0; x < newWidth; x++) {   
-        int tpos = map(newBuf[y*newWidth+x],0,255,0,noAsciiChars-1);
-        client.write(asciiArt[tpos]);
+        int tpos = map(newBuf[y*newWidth+x],0,255,0,noAsciiChars-1);       // convert pixel brightness to ascii character
+        client.write(asciiArt[noAsciiChars - tpos]);
       }
     }
     client.write("<br></pre>");
@@ -1641,7 +1649,7 @@ void readGreyscaleImage() {
   // change camera back to JPG mode
     esp_camera_deinit();  
     delay(50);
-    initialiseCamera(1);    // reset settings 
+    initialiseCamera(1);    // reset settings (1=apply the cameras settings which includes JPG mode)
   }
 
 

README.md

@@ -10,6 +10,7 @@ Note: There is a version of this sketch with OTA updates included here: https://
 <table><tr>
   <td><img src="/images/root.png" /></td>
   <td><img src="/images/rgb.png" /></td>
+  <td><img src="/images/grey.png" /></td>
 </tr></table> 
 
 This can be used as a starting point sketch for projects using the esp32cam development board, it has the following features.