From b3aaee8df3039891d79f4f673e6a8050d3fb65b5 Mon Sep 17 00:00:00 2001
From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
Date: Sat, 27 Feb 2016 13:31:55 +0100
Subject: [PATCH] Make an explicit flag for whether we have input signal or
 not, instead of trying to communicate it through the resolution.

---
 bmusb.cpp |  4 ++++
 bmusb.h   | 55 ++++++++++++++++++++++++++++++++++++++++++++-----------
 2 files changed, 48 insertions(+), 11 deletions(-)

diff --git a/bmusb.cpp b/bmusb.cpp
index 74643bc..4db8541 100644
--- a/bmusb.cpp
+++ b/bmusb.cpp
@@ -1150,6 +1150,7 @@ bool decode_video_format(uint16_t video_format, VideoFormat *decoded_video_forma
 		decoded_video_format->extra_lines_bottom = 0;
 		decoded_video_format->frame_rate_nom = 3013;
 		decoded_video_format->frame_rate_den = 100;
+		decoded_video_format->has_signal = false;
 		return true;
 	}
 	if ((video_format & 0xe800) != 0xe800) {
@@ -1161,9 +1162,12 @@ bool decode_video_format(uint16_t video_format, VideoFormat *decoded_video_forma
 		decoded_video_format->extra_lines_bottom = 0;
 		decoded_video_format->frame_rate_nom = 60;
 		decoded_video_format->frame_rate_den = 1;
+		decoded_video_format->has_signal = false;
 		return false;
 	}
 
+	decoded_video_format->has_signal = true;
+
 	// NTSC (480i59.94, I suppose). A special case, see below.
 	if (video_format == 0xe901 || video_format == 0xe9c1 || video_format == 0xe801) {
 		decoded_video_format->width = 720;
diff --git a/bmusb.h b/bmusb.h
index 04d867b..935318c 100644
--- a/bmusb.h
+++ b/bmusb.h
@@ -63,6 +63,7 @@ struct VideoFormat {
 	unsigned extra_lines_top = 0, extra_lines_bottom = 0;
 	unsigned frame_rate_nom = 0, frame_rate_den = 0;
 	bool interlaced = false;
+	bool has_signal = false;
 };
 
 typedef std::function<void(uint16_t timecode,
@@ -70,43 +71,74 @@ typedef std::function<void(uint16_t timecode,
                            FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format)>
 	frame_callback_t;
 
+class CaptureInterface {
+ public:
+	virtual ~CaptureInterface() {}
+
+	// Does not take ownership.
+	virtual void set_video_frame_allocator(FrameAllocator *allocator) = 0;
+
+	virtual FrameAllocator *get_video_frame_allocator() = 0;
+
+	// Does not take ownership.
+	virtual void set_audio_frame_allocator(FrameAllocator *allocator) = 0;
+
+	virtual FrameAllocator *get_audio_frame_allocator() = 0;
+
+	virtual void set_frame_callback(frame_callback_t callback) = 0;
+
+	// Needs to be run before configure_card().
+	virtual void set_dequeue_thread_callbacks(std::function<void()> init, std::function<void()> cleanup) = 0;
+
+	// Only valid after configure_card().
+	virtual std::string get_description() const = 0;
+
+	virtual void configure_card() = 0;
+
+	virtual void start_bm_capture() = 0;
+
+	virtual void stop_dequeue_thread() = 0;
+};
+
 // The actual capturing class, representing capture from a single card.
-class BMUSBCapture {
+class BMUSBCapture : public CaptureInterface {
  public:
 	BMUSBCapture(int card_index)
 		: card_index(card_index)
 	{
 	}
 
+	~BMUSBCapture() {}
+
 	// Does not take ownership.
-	void set_video_frame_allocator(FrameAllocator *allocator)
+	void set_video_frame_allocator(FrameAllocator *allocator) override
 	{
 		video_frame_allocator = allocator;
 	}
 
-	FrameAllocator *get_video_frame_allocator()
+	FrameAllocator *get_video_frame_allocator() override
 	{
 		return video_frame_allocator;
 	}
 
 	// Does not take ownership.
-	void set_audio_frame_allocator(FrameAllocator *allocator)
+	void set_audio_frame_allocator(FrameAllocator *allocator) override
 	{
 		audio_frame_allocator = allocator;
 	}
 
-	FrameAllocator *get_audio_frame_allocator()
+	FrameAllocator *get_audio_frame_allocator() override
 	{
 		return audio_frame_allocator;
 	}
 
-	void set_frame_callback(frame_callback_t callback)
+	void set_frame_callback(frame_callback_t callback) override
 	{
 		frame_callback = callback;
 	}
 
 	// Needs to be run before configure_card().
-	void set_dequeue_thread_callbacks(std::function<void()> init, std::function<void()> cleanup)
+	void set_dequeue_thread_callbacks(std::function<void()> init, std::function<void()> cleanup) override
 	{
 		dequeue_init_callback = init;
 		dequeue_cleanup_callback = cleanup;
@@ -114,14 +146,15 @@ class BMUSBCapture {
 	}
 
 	// Only valid after configure_card().
-	std::string get_description() const {
+	std::string get_description() const override {
 		return description;
 	}
 
-	void configure_card();
-	void start_bm_capture();
-	void stop_dequeue_thread();
+	void configure_card() override;
+	void start_bm_capture() override;
+	void stop_dequeue_thread() override;
 
+	// TODO: It's rather messy to have these outside the interface.
 	static void start_bm_thread();
 	static void stop_bm_thread();
 
-- 
2.39.2