Fix issues with the queue locking up when there is no signal.

[bmusb] / bmusb.cpp

diff --git a/bmusb.cpp b/bmusb.cpp
index 1079f2aa60932197799855c5b683470223a8c4ad..fbf31dd95177c8480dca45c6579ae696b126b7d2 100644 (file)
--- a/bmusb.cpp
+++ b/bmusb.cpp
@@ -52,7 +52,7 @@ atomic<bool> should_quit;
 
 FrameAllocator::~FrameAllocator() {}
 
-#define NUM_QUEUED_FRAMES 8
+#define NUM_QUEUED_FRAMES 16
 class MallocFrameAllocator : public FrameAllocator {
 public:
        MallocFrameAllocator(size_t frame_size);
@@ -93,6 +93,9 @@ FrameAllocator::Frame MallocFrameAllocator::alloc_frame()
 
 void MallocFrameAllocator::release_frame(Frame frame)
 {
+       if (frame.overflow > 0) {
+               printf("%d bytes overflow after last (malloc) frame\n", int(frame.overflow));
+       }
        unique_lock<mutex> lock(freelist_mutex);
        freelist.push(unique_ptr<uint8_t[]>(frame.data));
 }
@@ -195,6 +198,21 @@ void BMUSBCapture::start_new_frame(const uint8_t *start)
        uint16_t timecode = (start[1] << 8) | start[0];
 
        if (current_video_frame.len > 0) {
+               // If format is 0x0800 (no signal), add a fake (empty) audio
+               // frame to get it out of the queue.
+               // TODO: Figure out if there are other formats that come with
+               // no audio, and treat them the same.
+               if (format == 0x0800) {
+                       FrameAllocator::Frame fake_audio_frame = audio_frame_allocator->alloc_frame();
+                       if (fake_audio_frame.data == nullptr) {
+                               // Oh well, it's just a no-signal frame anyway.
+                               printf("Couldn't allocate fake audio frame, also dropping no-signal video frame.\n");
+                               current_video_frame.owner->release_frame(current_video_frame);
+                               current_video_frame = video_frame_allocator->alloc_frame();
+                               return;
+                       }
+                       queue_frame(format, timecode, fake_audio_frame, &pending_audio_frames);
+               }
                //dump_frame();
                queue_frame(format, timecode, current_video_frame, &pending_video_frames);
        }
@@ -263,8 +281,13 @@ void add_to_frame(FrameAllocator::Frame *current_frame, const char *frame_type_n
 
        int bytes = end - start;
        if (current_frame->len + bytes > current_frame->size) {
-               printf("%d bytes overflow after last %s frame\n",
-                       int(current_frame->len + bytes - current_frame->size), frame_type_name);
+               current_frame->overflow = current_frame->len + bytes - current_frame->size;
+               current_frame->len = current_frame->size;
+               if (current_frame->overflow > 1048576) {
+                       printf("%d bytes overflow after last %s frame\n",
+                               int(current_frame->overflow), frame_type_name);
+                       current_frame->overflow = 0;
+               }
                //dump_frame();
        } else {
                if (current_frame->interleaved) {