Resolves techyian#158 - Set framerate as double.

src/MMALSharp/Components/EncoderComponents/MMALVideoEncoder.cs

@@ -197,8 +197,9 @@ private void ConfigureQuantisationParameter(int outputPort)
 
         private void ConfigureVideoProfile(int outputPort)
         {
+            var rational = new MMAL_RATIONAL_T(MMALCameraConfig.Framerate);
             var macroblocks = (MMALCameraConfig.Resolution.Width >> 4) * (MMALCameraConfig.Resolution.Height >> 4);
-            var macroblocksPSec = macroblocks * (MMALCameraConfig.Framerate.Num / MMALCameraConfig.Framerate.Den);
+            var macroblocksPSec = macroblocks * (rational.Num / rational.Den);
 
             List<VideoLevel> videoLevels = GetNormalLevelLimits();
 

src/MMALSharp/Components/MMALCameraComponent.cs

@@ -189,7 +189,7 @@ public void Initialise(IOutputCaptureHandler stillCaptureHandler = null, IOutput
                                                                 1,
                                                                 MMALCameraConfig.Resolution.Width,
                                                                 MMALCameraConfig.Resolution.Height,
-                                                                3 + Math.Max(0, (MMALCameraConfig.Framerate.Num - 30) / 10),
+                                                                3 + Math.Max(0, (new MMAL_RATIONAL_T(MMALCameraConfig.Framerate).Num - 30) / 10),
                                                                 0,
                                                                 0,
                                                                 MMALCameraConfig.ClockMode);
@@ -228,7 +228,7 @@ private void InitialisePreview()
                 MMALCameraConfig.EncodingSubFormat,
                 width: MMALCameraConfig.Resolution.Width,
                 height: MMALCameraConfig.Resolution.Height,
-                framerate: MMALCameraConfig.Framerate.Num);
+                framerate: MMALCameraConfig.Framerate);
 
             MMALLog.Logger.LogDebug("Commit preview");
 
@@ -269,7 +269,7 @@ private void InitialiseVideo(IOutputCaptureHandler handler)
                 MMALCameraConfig.EncodingSubFormat,
                 width: currentWidth,
                 height: currentHeight,
-                framerate: MMALCameraConfig.Framerate.Num,
+                framerate: MMALCameraConfig.Framerate,
                 bufferNum: Math.Max(this.VideoPort.BufferNumRecommended, 3),
                 bufferSize: Math.Max(this.VideoPort.BufferSizeRecommended, this.VideoPort.BufferSizeMin),
                 crop: new Rectangle(0, 0, currentWidth, currentHeight));
@@ -340,7 +340,7 @@ private void InitialiseStill(IOutputCaptureHandler handler)
                     null,
                     width: currentWidth,
                     height: currentHeight,
-                    framerate: MMALCameraConfig.Framerate.Num,
+                    framerate: MMALCameraConfig.Framerate,
                     bufferNum: Math.Max(this.StillPort.BufferNumRecommended, 3),
                     bufferSize: Math.Max(this.StillPort.BufferSizeRecommended, this.StillPort.BufferSizeMin),
                     crop: new Rectangle(0, 0, currentWidth, currentHeight));
@@ -354,7 +354,7 @@ private void InitialiseStill(IOutputCaptureHandler handler)
                     MMALCameraConfig.EncodingSubFormat,
                     width: resolution.Width,
                     height: resolution.Height,
-                    framerate: MMALCameraConfig.Framerate.Num,
+                    framerate: MMALCameraConfig.Framerate,
                     bufferNum: Math.Max(this.StillPort.BufferNumRecommended, 3),
                     bufferSize: Math.Max(this.StillPort.BufferSizeRecommended, this.StillPort.BufferSizeMin),
                     crop: new Rectangle(0, 0, currentWidth, currentHeight));

src/MMALSharp/MMALCameraConfig.cs

@@ -183,7 +183,7 @@ public static class MMALCameraConfig
         /// <summary>
         /// The working framerate of the camera.
         /// </summary>
-        public static MMAL_RATIONAL_T Framerate { get; set; } = new MMAL_RATIONAL_T(30, 1);
+        public static double Framerate { get; set; } = 30;
 
         /*
          * -----------------------------------------------------------------------------------------------------------

src/MMALSharp/Native/MMALUtil.cs

@@ -2,7 +2,7 @@
 // Copyright (c) Ian Auty and contributors. All rights reserved.
 // Licensed under the MIT License. Please see LICENSE.txt for License info.
 // </copyright>
-
+using System;
 using System.Runtime.InteropServices;
 
 namespace MMALSharp.Native
@@ -180,15 +180,42 @@ public MMAL_FLOAT_RECT_T(double x, double y, double width, double height)
     [StructLayout(LayoutKind.Sequential)]
     public struct MMAL_RATIONAL_T
     {
-        private int num, den;
+        private int _num, _den;
+
+        public int Num => _num;
+        public int Den => _den;
 
-        public int Num => num;
-        public int Den => den;
+        /// <summary>
+        /// Creates a new <see cref="MMAL_RATIONAL_T"/> accepting a numerator value.
+        /// </summary>
+        /// <param name="num">The numerator.</param>
+        public MMAL_RATIONAL_T(double num)
+        {
+            if (num < 1)
+            {
+                var multiplier = 100;
+                var doubleNum = num * 100;
+
+                while (doubleNum < 1)
+                {
+                    doubleNum *= 10;
+                    multiplier *= 10;
+                }
+
+                _num = Convert.ToInt32(doubleNum);
+                _den = multiplier;
+            }
+            else
+            {
+                _num = Convert.ToInt32(num * 10);
+                _den = 10;
+            }
+        }
 
         public MMAL_RATIONAL_T(int num, int den)
         {
-            this.num = num;
-            this.den = den;
+            _num = num;
+            _den = den;
         }
     }
 }

src/MMALSharp/Ports/IMMALPortConfig.cs

@@ -38,7 +38,7 @@ public interface IMMALPortConfig
         /// <summary>
         /// The framerate of the outputted data.
         /// </summary>
-        int Framerate { get; }
+        double Framerate { get; }
 
         /// <summary>
         /// The quality of our outputted data. 

src/MMALSharp/Ports/IPort.cs

@@ -126,7 +126,12 @@ public interface IPort : IMMALObject
         /// <summary>
         /// The framerate we are processing data in.
         /// </summary>
-        MMAL_RATIONAL_T FrameRate { get; }
+        double FrameRate { get; }
+
+        /// <summary>
+        /// The framerate represented as a <see cref="MMAL_RATIONAL_T"/>.
+        /// </summary>
+        MMAL_RATIONAL_T FrameRateRational { get; }
 
         /// <summary>
         /// The working video color space, specific to video ports.

src/MMALSharp/Ports/Inputs/InputPort.cs

@@ -106,7 +106,7 @@ public virtual void Configure(IMMALPortConfig config, IPort copyPort, IInputCapt
 
                 if (config.Framerate > 0)
                 {
-                    this.FrameRate = new MMAL_RATIONAL_T(config.Framerate, 1);
+                    this.FrameRate = config.Framerate;
                 }
 
                 if (config.Bitrate > 0)

src/MMALSharp/Ports/MMALPortConfig.cs

@@ -38,7 +38,7 @@ public class MMALPortConfig : IMMALPortConfig
         /// <summary>
         /// The framerate of the outputted data.
         /// </summary>
-        public int Framerate { get; }
+        public double Framerate { get; }
 
         /// <summary>
         /// The quality value. Can be used with JPEG encoding (value between 1-100). Can be used with H.264 encoding which affects the quantization parameter (typical values between 10-40, see wiki for info). Set both bitrate param and quality param to 0 for variable bitrate.
@@ -112,7 +112,7 @@ public MMALPortConfig(
             bool storeMotionVectors = false,
             int width = 0, 
             int height = 0,
-            int framerate = 0,
+            double framerate = 0,
             bool zeroCopy = false,
             int bufferNum = 0, 
             int bufferSize = 0, 

src/MMALSharp/Ports/Outputs/OutputPort.cs

@@ -99,7 +99,7 @@ public virtual void Configure(IMMALPortConfig config, IInputPort copyFrom, IOutp
 
                 if (config.Framerate > 0)
                 {
-                    this.FrameRate = new MMAL_RATIONAL_T(config.Framerate, 1);
+                    this.FrameRate = config.Framerate;
                 }
 
                 if (config.Bitrate > 0)

src/MMALSharp/Ports/PortBase.cs

@@ -163,10 +163,18 @@ public Rectangle Crop
         /// <summary>
         /// The framerate we are processing data in.
         /// </summary>
-        public MMAL_RATIONAL_T FrameRate
+        public double FrameRate
+        {
+            get => this.Ptr->Format->Es->Video.FrameRate.Num;
+            internal set => this.Ptr->Format->Es->Video.FrameRate = new MMAL_RATIONAL_T(value);
+        }
+
+        /// <summary>
+        /// The framerate represented as a <see cref="MMAL_RATIONAL_T"/>.
+        /// </summary>
+        public MMAL_RATIONAL_T FrameRateRational
         {
             get => this.Ptr->Format->Es->Video.FrameRate;
-            internal set => this.Ptr->Format->Es->Video.FrameRate = new MMAL_RATIONAL_T(value.Num, value.Den);
         }
 
         /// <summary>

tests/MMALSharp.Tests/ConfigurationTests.cs

@@ -4,7 +4,6 @@
 // </copyright>
 
 using System;
-using System.Runtime.InteropServices;
 using MMALSharp.Common.Utility;
 using MMALSharp.Components;
 using MMALSharp.Config;
@@ -282,7 +281,7 @@ public void SetThenGetZoom(double x, double y, double width, double height)
         [MMALTestsAttribute]
         public void SetThenGetShutterSpeed(int shutterSpeed)
         {   
-            MMALCameraConfig.Framerate = new MMAL_RATIONAL_T(0, 0);
+            MMALCameraConfig.Framerate = 0;
             MMALCameraConfig.SensorMode = MMALSensorMode.Mode1;
             MMALCameraConfig.AwbMode = MMAL_PARAM_AWBMODE_T.MMAL_PARAM_AWBMODE_OFF;
             MMALCameraConfig.ShutterSpeed = shutterSpeed;
@@ -393,5 +392,19 @@ public void SetThenGetDigitalGain(double digitalGain)
                 Assert.ThrowsAny<Exception>(() => Fixture.MMALCamera.ConfigureCameraSettings());
             }
         }
+
+        [Theory]
+        [InlineData(25)]
+        [InlineData(25.5)]
+        [InlineData(0.005)]
+        [MMALTests]
+        public void SetThenGetFramerate(double framerate)
+        {
+            MMALCameraConfig.Framerate = framerate;
+
+            Fixture.MMALCamera.ConfigureCameraSettings();
+
+            Assert.True((double)Fixture.MMALCamera.Camera.StillPort.FrameRateRational.Num / Fixture.MMALCamera.Camera.StillPort.FrameRateRational.Den == framerate);
+        }
     }
 }

tests/MMALSharp.Tests/TestHelper.cs

@@ -34,7 +34,7 @@ public static void SetConfigurationDefaults()
             MMALCameraConfig.ShutterSpeed = 0;
             MMALCameraConfig.SensorMode = MMALSensorMode.Mode0;
             MMALCameraConfig.VideoStabilisation = true;
-            MMALCameraConfig.Framerate = new MMAL_RATIONAL_T(10, 1);
+            MMALCameraConfig.Framerate = 10;
             MMALCameraConfig.Encoding = MMALEncoding.OPAQUE;
             MMALCameraConfig.EncodingSubFormat = MMALEncoding.I420;
             MMALCameraConfig.VideoColorSpace = MMALEncoding.MMAL_COLOR_SPACE_ITUR_BT709;