Minor cleanup and a new webdemo

examples/demo.nim

@@ -1,10 +1,11 @@
 import mvb
 
 proc main() =
+  echo "Running MVB (🖥️ 👁️ 📒) Demo..."
   var frame: Mat
 
   # Create a GUI window
-  namedWindow "MVB - OpenCV Demo"
+  #namedWindow "MVB - OpenCV Demo"
 
   # Open the camera by callling the constructor
   let cap = newVideoCapture()
@@ -15,7 +16,7 @@ proc main() =
     # Start getting and showing frames
     while true:
       # Grab frame from camera
-      cap.read(frame)
+      cap.read frame
 
       # Display the frame
       imshow "MVB - OpenCV Demo", frame
@@ -28,6 +29,5 @@ proc main() =
   cap.release
   echo "👑"
 
-
 when isMainModule:
   main()

examples/webdemo.nim

@@ -0,0 +1,53 @@
+# To run:
+# $ nim cpp -r web3.nim
+#
+import asynchttpserver, asyncdispatch, asyncnet
+from std/posix import SIGINT, SIGTERM, onSignal
+import cppstl/std_vector
+import mvb
+
+const address = "127.0.0.1"
+const port = 8080
+
+# Camera set-up
+let cap = newVideoCapture()
+var frame: Mat
+
+# Server set-up
+const headers = {"Content-Type": "text/html; charset=utf-8"}
+
+# Get a frame from OpenCV: where the real magic happens...
+proc getFrame(): string =
+  cap.read(frame)
+  var buffer = initCppVector[uint8]()
+  var frameStr: string
+  imencode(".jpg", frame, buffer)
+  if buffer.len > 0:
+    frameStr = newString(buffer.len)
+    copyMem(frameStr.cstring, buffer[0].unsafeAddr, buffer.len)
+  else:
+    frameStr = newString(0)
+  result = frameStr
+
+proc cb(req: Request) {.async.} =
+  echo req.reqMethod, " ", req.url.path
+  if req.url.path == "/":
+    const response = "<h3>🖥️👁️📒 / mvb - web demo</h3>\n" &
+                      "<img src=\"/video\" width=\"100%\">"
+    await req.respond(Http200, response, headers.newHttpHeaders())
+
+  elif req.url.path == "/video":
+    await req.client.send("HTTP/1.1 200 OK\r\n" &
+                          "Content-Type: multipart/x-mixed-replace; boundary=frame\r\n\r\n")
+    while true:
+      await req.client.send("--frame\r\nContent-Type: image/jpeg\r\n\r\n" & getFrame() & "\r\n")
+  else:
+    await req.respond(Http404, "<h1 style='font-size: 200;'>🤷</h1>", headers.newHttpHeaders())
+
+onSignal(SIGINT, SIGTERM):
+  echo "⏹️  Stopping..."
+  quit()
+
+echo "▶️  Starting server at http://" & address & ":" & $port & "/"
+asyncCheck newAsyncHttpServer().serve(Port(port), cb, address)
+runForever()

mvb.nimble

@@ -12,8 +12,14 @@ backend       = "cpp"
 requires "nim >= 1.6.12"
 requires "cppstl"
 
+task i, "\t\tRun INim interpreter configured to use MVB":
+  exec "inim -d:--backend:cpp -d:'--passL:\"-lopencv_core -lopencv_imgcodecs -lopencv_highgui -lopencv_videoio\"'"
+
 task demo, "\t\tRun the demo":
-  exec "nim cpp -r examples/demo.nim"
+  exec "nim cpp -r --hints:off examples/demo.nim"
+
+task web_demo, "\t\tRun the web demo":
+  exec "nim cpp -r --hints:off examples/webdemo.nim"
 
 task test, "\t\tRun the test suite":
   exec "nim cpp -r --hints:off tests/test1.nim"

src/mvb.nim

@@ -1,4 +1,4 @@
-import cppstl/std_string
+import cppstl/std_string, cppstl/std_vector
 
 #{.passl: "-lopencv_core -lopencv_imgcodecs -lopencv_highgui -lopencv_videoio".}
 
@@ -78,12 +78,15 @@ const
   CAP_REALSENSE* = CAP_INTELPERC ## !< Synonym for CAP_INTELPERC
 
 # imgcodecs
-proc imread*(file: cstring, mode: ImreadModes = IMREAD_COLOR): Mat
+proc imread*(filename: cstring, mode: ImreadModes = IMREAD_COLOR): Mat
   {.importcpp: "cv::imread(@)", header: imgcodecs.}
 
-proc imwrite*(file: cstring, mat : Mat): bool
+proc imwrite*(filename: cstring, img : Mat): bool
   {.importcpp: "cv::imwrite(@)", header: imgcodecs, discardable.}
 
+proc imencode*(ext: cstring, img: Mat, buf: CppVector[uint8]): bool
+  {.importcpp: "cv::imencode(@)", header: imgcodecs, discardable.}
+
 # highgui
 proc namedWindow*(winname: cstring, flags : WindowFlags = WINDOW_AUTOSIZE)
   {.importcpp: "cv::namedWindow(@)", header: highgui, discardable.}

src/mvb.nim.cfg

@@ -1 +1 @@
---passL:"-lopencv_core -lopencv_imgcodecs -lopencv_highgui -lopencv_videoio"
+#--passL:"-lopencv_core -lopencv_imgcodecs -lopencv_highgui -lopencv_videoio"