Add a simple video decoding test

This application tests the BMediaTrack/BMediaFile API and underlying
ffmpeg plugin for video decoding. You can press (or hold) any key to go
through frames in a video. This avoids debugging both MediaPlayer and
the underlying libraries at the same time.

It shows that ReadFrames is getting video frames out of PTS order.

src/tests/kits/media/Jamfile

@@ -7,6 +7,10 @@ SimpleTest mediaFormats :
 	mediaFormats.cpp
 	: media ;
 
+SimpleTest VideoDecoder :
+	VideoDecoder.cpp
+	: media be ;
+
 UnitTestLib libmediatest.so :
 	MediaKitTestAddon.cpp
 

src/tests/kits/media/VideoDecoder.cpp

@@ -0,0 +1,131 @@
+/*
+ * Copyright 2017, Adrien Destugues, pulkomandy@pulkomandy.tk
+ * Distributed under terms of the MIT license.
+ */
+
+
+#include <Application.h>
+#include <Bitmap.h>
+#include <File.h>
+#include <MediaFile.h>
+#include <MediaTrack.h>
+#include <Window.h>
+
+#include <stdio.h>
+
+
+#pragma mark - VideoView
+
+
+class VideoView: public BView
+{
+	public:
+		VideoView::VideoView(BMediaTrack* track, int32 width, int32 height);
+		void Draw(BRect);
+		void KeyDown(const char*, int32);
+
+	private:
+		BMediaTrack*	fMediaTrack;
+		BBitmap			fBitmap;
+};
+
+
+VideoView::VideoView(BMediaTrack* track, int32 width, int32 height)
+	: BView(BRect(0, 0, width, height), "Video", B_FOLLOW_NONE,
+		B_WILL_DRAW)
+	, fMediaTrack(track)
+	, fBitmap(BRect(0, 0, width - 1, height - 1), B_RGB32)
+{
+}
+
+
+void
+VideoView::Draw(BRect r)
+{
+	DrawBitmap(&fBitmap);
+}
+		
+
+void
+VideoView::KeyDown(const char*, int32)
+{
+	puts("Next frame");
+	int64 count = 1;
+	fMediaTrack->ReadFrames(fBitmap.Bits(), &count);
+	Invalidate();
+}
+
+
+#pragma mark - VideoWindow
+
+
+class VideoWindow: public BWindow
+{
+public:
+	VideoWindow::VideoWindow(const char* videoFile);
+	VideoWindow::~VideoWindow();
+
+private:
+	BFile*			fFile;
+	BMediaFile*		fMediaFile;
+	BMediaTrack*	fMediaTrack;
+};
+
+
+VideoWindow::VideoWindow(const char* path)
+	: BWindow(BRect(60, 120, 700, 600), "Video Decoder",
+		B_DOCUMENT_WINDOW, B_QUIT_ON_WINDOW_CLOSE)
+	, fMediaTrack(NULL)
+{
+	fFile = new BFile(path, B_READ_ONLY);
+	fMediaFile = new BMediaFile(fFile);
+	media_format format;
+
+	int i;
+	for (i = fMediaFile->CountTracks(); --i >= 0;) {
+		BMediaTrack* mediaTrack = fMediaFile->TrackAt(i);
+
+		mediaTrack->EncodedFormat(&format);
+		if (format.IsVideo()) {
+			fMediaTrack = mediaTrack;
+			fMediaTrack->DecodedFormat(&format);
+			break;
+		}
+	}
+
+	if (fMediaTrack) {
+		printf("Found video track\n%ld x %ld ; %lld frames, %f seconds\n",
+			format.Width(), format.Height(), fMediaTrack->CountFrames(),
+			fMediaTrack->Duration() / 1000000.f);
+	} else {
+		return;
+	}
+
+	BView* view = new VideoView(fMediaTrack, format.Width(), format.Height());
+	AddChild(view);
+	view->MakeFocus();
+}
+
+
+VideoWindow::~VideoWindow()
+{
+	delete fMediaFile; // Also deletes the track
+	delete fFile;
+}
+
+
+#pragma mark - Main
+
+
+int main(int argc, char* argv[])
+{
+	if (argc < 2)
+		return -1;
+
+	BApplication app("application/x-vnd.Haiku-VideoDecoder");
+
+	BWindow* window = new VideoWindow(argv[1]);
+	window->Show();
+
+	app.Run();
+}