Make it possible to choose the DeckLink output video mode through the GUI.

[nageru] / decklink_output.cpp

diff --git a/decklink_output.cpp b/decklink_output.cpp
index 38f44ee96c4d614e2d9ed2729ad2cc42e185eec8..55d29c5aad38c8d5be43f30ef677a2c9bb9ef032 100644 (file)
--- a/decklink_output.cpp
+++ b/decklink_output.cpp
@@ -302,6 +302,33 @@ void DeckLinkOutput::wait_for_frame(int64_t pts, int *dropped_frames, int64_t *f
        fprintf(stderr, "Dropped %d output frames; skipping.\n", *dropped_frames);
 }
 
+uint32_t DeckLinkOutput::pick_video_mode(uint32_t mode) const
+{
+       if (video_modes.count(mode)) {
+               return mode;
+       }
+
+       // Prioritize 59.94 > 60 > 29.97. If none of those are found, then pick the highest one.
+       for (const pair<int, int> &desired : vector<pair<int, int>>{ { 60000, 1001 }, { 60, 0 }, { 30000, 1001 } }) {
+               for (const auto &it : video_modes) {
+                       if (it.second.frame_rate_num * desired.second == desired.first * it.second.frame_rate_den) {
+                               return it.first;
+                       }
+               }
+       }
+
+       uint32_t best_mode = 0;
+       double best_fps = 0.0;
+       for (const auto &it : video_modes) {
+               double fps = double(it.second.frame_rate_num) / it.second.frame_rate_den;
+               if (fps > best_fps) {
+                       best_mode = it.first;
+                       best_fps = fps;
+               }
+       }
+       return best_mode;
+}
+
 HRESULT DeckLinkOutput::ScheduledFrameCompleted(/* in */ IDeckLinkVideoFrame *completedFrame, /* in */ BMDOutputFrameCompletionResult result)
 {
        Frame *frame = static_cast<Frame *>(completedFrame);