From b434c61b86e6c8ce733476371639fa0aeb5f80b2 Mon Sep 17 00:00:00 2001
From: Johanness <mrjitten@protonmail.com>
Date: Sat, 30 May 2026 23:24:54 +0300
Subject: [PATCH] decklink-out: non-blocking frame pool, skip late frames
 instead of realign, 5 preroll frames

---
 nodes/decklink-out/src/decklink_out_node.cpp | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/nodes/decklink-out/src/decklink_out_node.cpp b/nodes/decklink-out/src/decklink_out_node.cpp
index 2f6ed87..e770e10 100644
--- a/nodes/decklink-out/src/decklink_out_node.cpp
+++ b/nodes/decklink-out/src/decklink_out_node.cpp
@@ -157,7 +157,7 @@ bool DeckLinkOutNode::open_device() {
                      is_interlaced_);
     }
 
-    preroll_frames_ = 3;
+    preroll_frames_ = 5;
     for (int i = 0; i < preroll_frames_; ++i) {
         IDeckLinkMutableVideoFrame* frame = nullptr;
         int32_t out_row_bytes = out_width_ * 16 / 6;
@@ -239,8 +239,8 @@ void DeckLinkOutNode::schedule_frame(void* mxl_payload, long width, long height,
 
     IDeckLinkMutableVideoFrame* frame = nullptr;
     {
-        std::unique_lock<std::mutex> lock(frame_pool_mutex_);
-        if (frame_pool_cv_.wait_for(lock, std::chrono::milliseconds(100), [this] { return !frame_pool_.empty(); })) {
+        std::lock_guard<std::mutex> lock(frame_pool_mutex_);
+        if (!frame_pool_.empty()) {
             frame = frame_pool_.back();
             frame_pool_.pop_back();
         }
@@ -295,16 +295,18 @@ void DeckLinkOutNode::process() {
     uint8_t* payload = nullptr;
     auto status = mxlFlowReaderGetGrain(*reader_, source_index, 5000000ULL, &grain_info, &payload);
     if (status != MXL_STATUS_OK) {
-        if (status == MXL_ERR_OUT_OF_RANGE_TOO_LATE || status == MXL_ERR_OUT_OF_RANGE_TOO_EARLY) {
+        if (status == MXL_ERR_OUT_OF_RANGE_TOO_LATE) {
             auto now = mxlGetTime();
             auto current_index = mxlTimestampToIndex(&flow_rate_, now);
-            spdlog::warn("DeckLink-out: realigned from {} to {}", source_index, current_index - 2);
+            spdlog::warn("DeckLink-out: grain too late, skipping to index {}", current_index - 2);
             source_index = current_index - 2;
-
             status = mxlFlowReaderGetGrain(*reader_, source_index, 5000000ULL, &grain_info, &payload);
             if (status != MXL_STATUS_OK) {
+                grains_read_++;
                 return;
             }
+        } else if (status == MXL_ERR_OUT_OF_RANGE_TOO_EARLY) {
+            return;
         } else {
             return;
         }
@@ -320,7 +322,6 @@ void DeckLinkOutNode::process() {
 
     schedule_frame(payload, src_width, src_height, src_row_bytes);
 
-    read_index_ = source_index + 1;
     grains_read_++;
 
     if (grains_read_ == 1) {