#include <condition_variable>
#include <deque>
#include <functional>
+#include <map>
#include <mutex>
+#include <stack>
#include <string>
#include <thread>
#include <vector>
virtual void release_frame(Frame frame) = 0;
};
+// Audio is more important than video, and also much cheaper.
+// By having many more audio frames available, hopefully if something
+// starts to drop, we'll have CPU load go down (from not having to
+// process as much video) before we have to drop audio.
+#define NUM_QUEUED_VIDEO_FRAMES 16
+#define NUM_QUEUED_AUDIO_FRAMES 64
+
+class MallocFrameAllocator : public FrameAllocator {
+public:
+ MallocFrameAllocator(size_t frame_size, size_t num_queued_frames);
+ Frame alloc_frame() override;
+ void release_frame(Frame frame) override;
+
+private:
+ size_t frame_size;
+
+ std::mutex freelist_mutex;
+ std::stack<std::unique_ptr<uint8_t[]>> freelist; // All of size <frame_size>.
+};
+
+// Represents an input mode you can tune a card to.
+struct VideoMode {
+ std::string name;
+ bool autodetect = false; // If true, all the remaining fields are irrelevant.
+ unsigned width = 0, height = 0;
+ unsigned frame_rate_num = 0, frame_rate_den = 0;
+ bool interlaced = false;
+};
+
+// Represents the format of an actual frame coming in.
struct VideoFormat {
uint16_t id = 0; // For debugging/logging only.
unsigned width = 0, height = 0, second_field_start = 0;
bool has_signal = false;
};
+struct AudioFormat {
+ uint16_t id = 0; // For debugging/logging only.
+ unsigned bits_per_sample = 0;
+ unsigned num_channels = 0;
+};
+
typedef std::function<void(uint16_t timecode,
FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
- FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format)>
+ FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format)>
frame_callback_t;
class CaptureInterface {
public:
virtual ~CaptureInterface() {}
+ virtual std::map<uint32_t, VideoMode> get_available_video_modes() const = 0;
+
+ virtual void set_video_mode(uint32_t video_mode_id) = 0;
+
// Does not take ownership.
virtual void set_video_frame_allocator(FrameAllocator *allocator) = 0;
~BMUSBCapture() {}
+ std::map<uint32_t, VideoMode> get_available_video_modes() const override;
+
+ void set_video_mode(uint32_t video_mode_id) override;
+
// Does not take ownership.
void set_video_frame_allocator(FrameAllocator *allocator) override
{