minor cleanup

Author: cgreening

streaming_gif/main/gif_to_jpeg.cpp

@@ -95,7 +95,7 @@ bool gif_to_jpeg_preencode(const uint8_t *gif_data,
             uint64_t end_time_us = esp_timer_get_time();
             total_decode_time_us += end_decode_time_us - start_time_us;
             total_encode_time_us += end_time_us - end_decode_time_us;
-            ESP_LOGI(TAG, "Frame %d decoded in %llu us and encoded in %llu us, size %d", store.count(), end_decode_time_us - start_time_us, end_time_us - end_decode_time_us, jpeg_len);
+            ESP_LOGI(TAG, "Frame %d decoded in %llu us and encoded in %llu us, size %d, delay %dms", store.count(), end_decode_time_us - start_time_us, end_time_us - end_decode_time_us, jpeg_len, delay_ms);
         }
     }
 

streaming_gif/main/uvc_streamer.cpp

@@ -57,51 +57,23 @@ uvc_fb_t *UvcStreamer::fbGet()
         return nullptr;
     }
 
-    const uint64_t now_us = static_cast<uint64_t>(esp_timer_get_time());
+    const int64_t now_us = esp_timer_get_time();
 
-    if (last_frame_time_us_ == 0) {
-        current_frame_ = 0;
-        last_frame_time_us_ = now_us;
+    // just started to steeam
+    if (current_frame_start_time_us_ == 0) {
+        current_frame_index_ = 0;
+        current_frame_start_time_us_ = now_us;
     }
+    // this much time has passed since the last frame time
+    const int64_t elapsed_us = now_us - current_frame_start_time_us_;
 
-    // Advance frames based on per-frame delays. Use a catch-up loop so if the host
-    // polls infrequently, we don't "slow down" the animation permanently.
-    //
-    // Safety: bound iterations so we never spin if delays are odd.
-    int safety = store_.count() + 1;
-    while (safety-- > 0) {
-        const FrameStore::Frame *cur = store_.get(current_frame_);
-        if (cur == nullptr) {
-            current_frame_ = 0;
-            last_frame_time_us_ = now_us;
-            break;
-        }
-
-        int delay_ms = cur->delayMs();
-        if (delay_ms < kMinFrameDelayMs) {
-            delay_ms = kMinFrameDelayMs;
-        }
-
-        const uint64_t elapsed_ms = (now_us - last_frame_time_us_) / 1000ULL;
-        if (elapsed_ms < static_cast<uint64_t>(delay_ms)) {
-            break;
-        }
-
-        current_frame_ = (current_frame_ + 1) % store_.count();
-        last_frame_time_us_ += static_cast<uint64_t>(delay_ms) * 1000ULL;
-        if (last_frame_time_us_ > now_us) {
-            // In case of timer anomalies, re-anchor.
-            last_frame_time_us_ = now_us;
-            break;
-        }
+    // do we need to move to the next frame?
+    if (elapsed_us > store_.get(current_frame_index_)->delayMs() * 1000) {
+        current_frame_index_ = (current_frame_index_ + 1) % store_.count();
+        current_frame_start_time_us_ = now_us;
     }
 
-    if (safety <= 0) {
-        // We advanced "a lot" in one go; re-anchor to avoid repeated catch-up work.
-        last_frame_time_us_ = now_us;
-    }
-
-    const FrameStore::Frame *f = store_.get(current_frame_);
+    const FrameStore::Frame *f = store_.get(current_frame_index_);
     if (f == nullptr) {
         return nullptr;
     }

streaming_gif/main/uvc_streamer.h

@@ -59,8 +59,8 @@ class UvcStreamer {
     uvc_fb_t *fbGet();
 
     const FrameStore &store_;
-    int current_frame_ = 0;
-    uint64_t last_frame_time_us_ = 0;
+    int current_frame_index_ = 0;
+    uint64_t current_frame_start_time_us_ = 0;
     size_t max_frame_size_ = 0;
     uint8_t *uvc_buffer_ = nullptr;
     uvc_fb_t fb_{};