Add image publishing functionality to Litter Box Camera: implement base64 encoding and MQTT publishing on image capture

esphome/litter-box-cam.yaml

@@ -113,11 +113,15 @@ globals:
     type: int
     restore_value: yes
     initial_value: '0'
-  
+
   - id: motion_cooldown_active
     type: bool
     initial_value: 'false'
 
+  - id: publish_next_image
+    type: bool
+    initial_value: 'false'
+
 # -----------------------------------------------------------------------------
 # Camera Configuration (OV3660 - DFR1154 Specific)
 # -----------------------------------------------------------------------------
@@ -150,6 +154,36 @@ esp32_camera:
   brightness: 0
   contrast: 1
   saturation: 0
+  on_image:
+    then:
+      - lambda: |-
+          if (!id(publish_next_image)) return;
+          id(publish_next_image) = false;
+
+          const uint8_t *data = x->get_data();
+          size_t len = x->get_data_length();
+          size_t out_len = 4 * ((len + 2) / 3);
+          char *buf = (char *)malloc(out_len + 1);
+          if (!buf) return;
+
+          static const char b64[] =
+            "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+          size_t j = 0;
+          for (size_t i = 0; i < len; i += 3) {
+            uint32_t b = ((uint32_t)data[i] << 16);
+            if (i + 1 < len) b |= ((uint32_t)data[i + 1] << 8);
+            if (i + 2 < len) b |= data[i + 2];
+            buf[j++] = b64[(b >> 18) & 0x3F];
+            buf[j++] = b64[(b >> 12) & 0x3F];
+            buf[j++] = (i + 1 < len) ? b64[(b >> 6) & 0x3F] : '=';
+            buf[j++] = (i + 2 < len) ? b64[b & 0x3F] : '=';
+          }
+          buf[j] = '\0';
+
+          id(mqtt_client).publish("litter_box/camera/image", buf);
+          ESP_LOGI("capture", "Published image (%d bytes raw, %d base64)", len, j);
+          id(status_message).publish_state("Image sent for analysis");
+          free(buf);
 
 # Web server for manual viewing
 esp32_camera_web_server:
@@ -293,26 +327,8 @@ script:
       - light.turn_on: status_led
       - delay: 200ms
       - lambda: |-
-          auto cam = id(litter_cam);
+          id(publish_next_image) = true;
-          camera::Camera::FrameBuffer *fb = cam->get_image();
+          id(litter_cam).request_image(esphome::esp32_camera::SINGLE_SHOT);
-          if (fb) {
-            size_t out_len = 4 * ((fb->length + 2) / 3);
-            char *base64_buffer = (char *)malloc(out_len + 1);
-            if (base64_buffer) {
-              size_t encoded_len = 0;
-              int ret = mbedtls_base64_encode(
-                (unsigned char *)base64_buffer, out_len + 1, &encoded_len,
-                fb->buf, fb->length);
-              if (ret == 0) {
-                base64_buffer[encoded_len] = '\0';
-                id(mqtt_client).publish("litter_box/camera/image", base64_buffer);
-                ESP_LOGI("capture", "Published image");
-                id(status_message).publish_state("Image sent for analysis");
-              }
-              free(base64_buffer);
-            }
-            cam->return_image(fb);
-          }
       - light.turn_off: status_led
       - lambda: 'id(motion_cooldown_active) = true;'
       - delay: 30s