From 132b88337bb04ccf34389e50d07650c759bb33ff Mon Sep 17 00:00:00 2001
From: Claude Worker claude2 <claude2@MacBookPro.lan>
Date: Thu, 11 Jun 2026 02:03:13 +0200
Subject: [PATCH] fix(qr): adaptive frame size + OV3660 tuning

---
 .../components/local_puzzles/qr_puzzle.c      | 73 ++++++++++++-------
 1 file changed, 45 insertions(+), 28 deletions(-)

diff --git a/idf_zacus/components/local_puzzles/qr_puzzle.c b/idf_zacus/components/local_puzzles/qr_puzzle.c
index caf3fbf..f3e1d9a 100644
--- a/idf_zacus/components/local_puzzles/qr_puzzle.c
+++ b/idf_zacus/components/local_puzzles/qr_puzzle.c
@@ -64,43 +64,48 @@ static void scan_task(void *arg) {
         vTaskDelete(NULL);
         return;
     }
-    if (quirc_resize(q, QR_WIDTH, QR_HEIGHT) < 0) {
-        ESP_LOGE(TAG, "quirc_resize(%d,%d) failed", QR_WIDTH, QR_HEIGHT);
-        quirc_destroy(q);
-        esp_camera_deinit();
-        s_task = NULL;
-        vTaskDelete(NULL);
-        return;
-    }
+    // quirc is (re)sized to the camera's ACTUAL frame geometry. The OV3660
+    // on this board does not always deliver exactly QVGA — adapt at runtime
+    // instead of dropping every off-size frame (the old fixed 320x240 guard
+    // silently starved quirc when the sensor returned another size).
+    int q_w = 0, q_h = 0;
 
     while (s_run) {
         camera_fb_t *fb = esp_camera_fb_get();
         if (!fb) { vTaskDelay(pdMS_TO_TICKS(50)); continue; }
 
-        // Guard: only copy if the frame geometry matches what quirc was sized to.
-        if (fb->width == QR_WIDTH && fb->height == QR_HEIGHT) {
-            if (s_preview_cb) s_preview_cb(fb->buf, QR_WIDTH, QR_HEIGHT);
+        if (fb->width != q_w || fb->height != q_h) {
+            if (quirc_resize(q, fb->width, fb->height) < 0) {
+                ESP_LOGE(TAG, "quirc_resize(%d,%d) failed", fb->width, fb->height);
+                esp_camera_fb_return(fb);
+                vTaskDelay(pdMS_TO_TICKS(50));
+                continue;
+            }
+            q_w = fb->width;
+            q_h = fb->height;
+            ESP_LOGI(TAG, "scanning at sensor geometry %dx%d", q_w, q_h);
+        }
 
-            uint8_t *img = quirc_begin(q, NULL, NULL);
-            memcpy(img, fb->buf, (size_t)QR_WIDTH * QR_HEIGHT);
-            quirc_end(q);
+        if (s_preview_cb) s_preview_cb(fb->buf, q_w, q_h);
 
-            int n = quirc_count(q);
-            for (int i = 0; i < n; i++) {
-                // static: ~12.5 KB total — too large for the task stack; single-instance task.
-                static struct quirc_code code;
-                static struct quirc_data data;
-                quirc_extract(q, i, &code);
-                if (quirc_decode(&code, &data) == 0) {
-                    // data.payload is a NUL-terminated uint8_t string for text QRs.
-                    if (seq_validator_feed(&s_seq, (const char *)data.payload)) {
-                        if (s_cb) s_cb();
-                        s_run = false;
-                    }
+        uint8_t *img = quirc_begin(q, NULL, NULL);
+        memcpy(img, fb->buf, (size_t)q_w * q_h);
+        quirc_end(q);
+
+        int n = quirc_count(q);
+        for (int i = 0; i < n; i++) {
+            // static: ~12.5 KB total — too large for the task stack; single-instance task.
+            static struct quirc_code code;
+            static struct quirc_data data;
+            quirc_extract(q, i, &code);
+            if (quirc_decode(&code, &data) == 0) {
+                // data.payload is a NUL-terminated uint8_t string for text QRs.
+                ESP_LOGI(TAG, "QR decoded: %s", (const char *)data.payload);
+                if (seq_validator_feed(&s_seq, (const char *)data.payload)) {
+                    if (s_cb) s_cb();
+                    s_run = false;
                 }
             }
-        } else {
-            ESP_LOGW(TAG, "unexpected frame size %dx%d, skipping", fb->width, fb->height);
         }
 
         esp_camera_fb_return(fb); // always return the frame
@@ -126,6 +131,18 @@ esp_err_t qr_puzzle_start(const char *const *expected, size_t count, qr_solved_c
         return e;
     }
 
+    // Tune the OV3660 for QR decoding off a backlit LCD: max contrast +
+    // sharpness, and cap the gain/exposure so the bright screen does not
+    // bloom and wash out the QR modules.
+    sensor_t *s = esp_camera_sensor_get();
+    if (s) {
+        if (s->set_contrast)   s->set_contrast(s, 2);
+        if (s->set_sharpness)  s->set_sharpness(s, 2);
+        if (s->set_gainceiling) s->set_gainceiling(s, GAINCEILING_2X);
+        if (s->set_whitebal)   s->set_whitebal(s, 1);
+        if (s->set_aec2)       s->set_aec2(s, 1);
+    }
+
     seq_validator_init(&s_seq, expected, count);
     s_cb  = cb;
     s_run = true;