Add OV3660 camera support for AI Thinker ESP32-CAM

The esp32-camera library already includes a full OV3660 driver, so no
library changes are needed. This commit wires in the sensor-specific
initialization the OV3660 requires:

- Increase XCLK from 15 MHz to 20 MHz in InitCameraModule(); the OV3660
  requires 20 MHz and the OV2640 is compatible with both frequencies
- Apply OV3660-specific settings in ApplyCameraCfg() when the detected
  sensor PID matches OV3660_PID: enable vflip (sensor image is natively
  inverted), reduce initial saturation, and clamp frame size to SXGA
  (1280x1024) if a larger size was stored in EEPROM, since UXGA exceeds
  the OV3660's maximum resolution
- Update CAMERA_MODEL EXIF string from "OV2640" to "OV3660"
- Add OV3660 to the supported camera modules table in the AI Thinker
  README
- Add build/ to .gitignore to exclude Arduino IDE compiled output

.gitignore

@@ -41,7 +41,8 @@
 .LSOverride
 
 # Icon must end with two \r
-Icon
+Icon
+
 
 # Thumbnails
 ._*
@@ -68,3 +69,6 @@ Temporary Items
 
 # End of https://www.toptal.com/developers/gitignore/api/c++,macos
 
+# Arduino IDE build output
+build/
+

ESP32_PrusaConnectCam/camera.cpp

@@ -107,7 +107,7 @@ void Camera::InitCameraModule() {
   CameraConfig.pin_sccb_scl = SIOC_GPIO_NUM;
   CameraConfig.pin_pwdn = PWDN_GPIO_NUM;
   CameraConfig.pin_reset = RESET_GPIO_NUM;
-  CameraConfig.xclk_freq_hz = 15000000;       // or 3000000; 16500000; 20000000
+  CameraConfig.xclk_freq_hz = 20000000;       // or 3000000; 15000000; 16500000
   CameraConfig.pixel_format = PIXFORMAT_JPEG; /* YUV422,GRAYSCALE,RGB565,JPEG */
 
   /* OV2640
@@ -322,6 +322,18 @@ void Camera::ApplyCameraCfg() {
   sensor->set_vflip(sensor, vflip);                   // vertical flip 0 = disable , 1 = enable
   sensor->set_dcw(sensor, 1);                         // 0 = disable , 1 = enable
   sensor->set_colorbar(sensor, 0);                    // external collor lines, 0 = disable , 1 = enable
+
+  /* OV3660-specific initialization */
+  if (sensor->id.PID == OV3660_PID) {
+    sensor->set_vflip(sensor, 1);          // OV3660 image is natively inverted
+    sensor->set_saturation(sensor, -2);    // reduce initial oversaturation
+    /* OV3660 max resolution is SXGA (1280x1024); clamp if a larger size was stored */
+    if (TFrameSize > FRAMESIZE_SXGA) {
+      log->AddEvent(LogLevel_Warning, F("OV3660: frame size exceeds SXGA, clamping"));
+      TFrameSize = FRAMESIZE_SXGA;
+      sensor->set_framesize(sensor, FRAMESIZE_SXGA);
+    }
+  }
 }
 
 /**

ESP32_PrusaConnectCam/mcu_cfg.h

@@ -13,13 +13,13 @@
 #define _MCU_CFG_H_
 
 /* ----------------- CAMERA TYPE  ---------------*/
-#define AI_THINKER_ESP32_CAM            true
+#define AI_THINKER_ESP32_CAM            true
-#define ESP32_WROVER_DEV                false
+#define ESP32_WROVER_DEV                false
-#define CAMERA_MODEL_ESP32_S3_DEV_CAM   false
+#define CAMERA_MODEL_ESP32_S3_DEV_CAM   false
-#define CAMERA_MODEL_ESP32_S3_EYE_2_2   false
+#define CAMERA_MODEL_ESP32_S3_EYE_2_2   false
-#define CAMERA_MODEL_XIAO_ESP32_S3_CAM  false
+#define CAMERA_MODEL_XIAO_ESP32_S3_CAM  false
-#define CAMERA_MODEL_ESP32_S3_CAM       false
+#define CAMERA_MODEL_ESP32_S3_CAM       false
-#define ESP32_S3_WROOM_FREENOVE         false
+#define ESP32_S3_WROOM_FREENOVE         false
 
 /* ---------------- BASIC MCU CFG  --------------*/
 #define SW_VERSION                  "1.1.2"                 ///< SW version
@@ -100,7 +100,7 @@
 
 /* ------------------ EXIF CFG ------------------*/
 #define CAMERA_MAKE                 "OmniVision"            ///< Camera make string
-#define CAMERA_MODEL                "OV2640"                ///< Camera model string
+#define CAMERA_MODEL                "OV3660"                ///< Camera model string
 #define CAMERA_SOFTWARE             "Prusa ESP32-cam"       ///< Camera software string
 #define CAMERA_EXIF_ROTATION_STREAM false                   ///< enable camera exif rotation for stream
 

doc/AI_Thinker-ESP32-cam/README.md

@@ -56,6 +56,7 @@ These are currently known or tested camera modules:
 | OV2640IR    | 160° |    2MP     |   Yes  |  Yes  |                                          |
 | OV8225N     | 66°  |    2MP     |   Yes  |  Yes  |                                          |
 | OV3360      | 66°  |    3MP     |   Yes  |  Yes  |                                          |
+| OV3660      | 66°  |    3MP     |   Yes  |  Yes  | Max resolution SXGA (1280x1024)          |
 | OV5640-AF   | 72°  |    5MP     |   Yes  |  Yes  | Overheating, slow photo loading          |
 
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