2019-06-21 01:12:49 +03:00

246 lines
8.7 KiB
C#

// AForge Direct Show Library
// AForge.NET framework
// http://www.aforgenet.com/framework/
//
// Copyright © AForge.NET, 2009-2013
// contacts@aforgenet.com
//
namespace AForge.Video.DirectShow
{
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Runtime.InteropServices;
using AForge.Video;
using AForge.Video.DirectShow.Internals;
/// <summary>
/// Capabilities of video device such as frame size and frame rate.
/// </summary>
public class VideoCapabilities
{
/// <summary>
/// Frame size supported by video device.
/// </summary>
public readonly Size FrameSize;
/// <summary>
/// Frame rate supported by video device for corresponding <see cref="FrameSize">frame size</see>.
/// </summary>
///
/// <remarks><para><note>This field is depricated - should not be used.
/// Its value equals to <see cref="AverageFrameRate"/>.</note></para>
/// </remarks>
///
[Obsolete( "No longer supported. Use AverageFrameRate instead." )]
public int FrameRate
{
get { return AverageFrameRate; }
}
/// <summary>
/// Average frame rate of video device for corresponding <see cref="FrameSize">frame size</see>.
/// </summary>
public readonly int AverageFrameRate;
/// <summary>
/// Maximum frame rate of video device for corresponding <see cref="FrameSize">frame size</see>.
/// </summary>
public readonly int MaximumFrameRate;
/// <summary>
/// Number of bits per pixel provided by the camera.
/// </summary>
public readonly int BitCount;
internal VideoCapabilities( ) { }
// Retrieve capabilities of a video device
static internal VideoCapabilities[] FromStreamConfig( IAMStreamConfig videoStreamConfig )
{
if ( videoStreamConfig == null )
throw new ArgumentNullException( "videoStreamConfig" );
// ensure this device reports capabilities
int count, size;
int hr = videoStreamConfig.GetNumberOfCapabilities( out count, out size );
if ( hr != 0 )
Marshal.ThrowExceptionForHR( hr );
if ( count <= 0 )
throw new NotSupportedException( "This video device does not report capabilities." );
if ( size > Marshal.SizeOf( typeof( VideoStreamConfigCaps ) ) )
throw new NotSupportedException( "Unable to retrieve video device capabilities. This video device requires a larger VideoStreamConfigCaps structure." );
// group capabilities with similar parameters
Dictionary<uint, VideoCapabilities> videocapsList = new Dictionary<uint, VideoCapabilities>( );
for ( int i = 0; i < count; i++ )
{
try
{
VideoCapabilities vc = new VideoCapabilities( videoStreamConfig, i );
uint key = ( ( (uint) vc.FrameSize.Height ) << 32 ) |
( ( (uint) vc.FrameSize.Width ) << 16 );
if ( !videocapsList.ContainsKey( key ) )
{
videocapsList.Add( key, vc );
}
else
{
if ( vc.BitCount > videocapsList[key].BitCount )
{
videocapsList[key] = vc;
}
}
}
catch
{
}
}
VideoCapabilities[] videocaps = new VideoCapabilities[videocapsList.Count];
videocapsList.Values.CopyTo( videocaps, 0 );
return videocaps;
}
// Retrieve capabilities of a video device
internal VideoCapabilities( IAMStreamConfig videoStreamConfig, int index )
{
AMMediaType mediaType = null;
VideoStreamConfigCaps caps = new VideoStreamConfigCaps( );
try
{
// retrieve capabilities struct at the specified index
int hr = videoStreamConfig.GetStreamCaps( index, out mediaType, caps );
if ( hr != 0 )
Marshal.ThrowExceptionForHR( hr );
if ( mediaType.FormatType == FormatType.VideoInfo )
{
VideoInfoHeader videoInfo = (VideoInfoHeader) Marshal.PtrToStructure( mediaType.FormatPtr, typeof( VideoInfoHeader ) );
FrameSize = new Size( videoInfo.BmiHeader.Width, videoInfo.BmiHeader.Height );
BitCount = videoInfo.BmiHeader.BitCount;
AverageFrameRate = (int) ( 10000000 / videoInfo.AverageTimePerFrame );
MaximumFrameRate = (int) ( 10000000 / caps.MinFrameInterval );
}
else if ( mediaType.FormatType == FormatType.VideoInfo2 )
{
VideoInfoHeader2 videoInfo = (VideoInfoHeader2) Marshal.PtrToStructure( mediaType.FormatPtr, typeof( VideoInfoHeader2 ) );
FrameSize = new Size( videoInfo.BmiHeader.Width, videoInfo.BmiHeader.Height );
BitCount = videoInfo.BmiHeader.BitCount;
AverageFrameRate = (int) ( 10000000 / videoInfo.AverageTimePerFrame );
MaximumFrameRate = (int) ( 10000000 / caps.MinFrameInterval );
}
else
{
throw new ApplicationException( "Unsupported format found." );
}
// ignore 12 bpp formats for now, since it was noticed they cause issues on Windows 8
// TODO: proper fix needs to be done so ICaptureGraphBuilder2::RenderStream() does not fail
// on such formats
if ( BitCount <= 12 )
{
throw new ApplicationException( "Unsupported format found." );
}
}
finally
{
if ( mediaType != null )
mediaType.Dispose( );
}
}
/// <summary>
/// Check if the video capability equals to the specified object.
/// </summary>
///
/// <param name="obj">Object to compare with.</param>
///
/// <returns>Returns true if both are equal are equal or false otherwise.</returns>
///
public override bool Equals( object obj )
{
return Equals( obj as VideoCapabilities );
}
/// <summary>
/// Check if two video capabilities are equal.
/// </summary>
///
/// <param name="vc2">Second video capability to compare with.</param>
///
/// <returns>Returns true if both video capabilities are equal or false otherwise.</returns>
///
public bool Equals( VideoCapabilities vc2 )
{
if ( (object) vc2 == null )
{
return false;
}
return ( ( FrameSize == vc2.FrameSize ) && ( BitCount == vc2.BitCount ) );
}
/// <summary>
/// Get hash code of the object.
/// </summary>
///
/// <returns>Returns hash code ot the object </returns>
public override int GetHashCode( )
{
return FrameSize.GetHashCode( ) ^ BitCount;
}
/// <summary>
/// Equality operator.
/// </summary>
///
/// <param name="a">First object to check.</param>
/// <param name="b">Seconds object to check.</param>
///
/// <returns>Return true if both objects are equal or false otherwise.</returns>
public static bool operator ==( VideoCapabilities a, VideoCapabilities b )
{
// if both are null, or both are same instance, return true.
if ( object.ReferenceEquals( a, b ) )
{
return true;
}
// if one is null, but not both, return false.
if ( ( (object) a == null ) || ( (object) b == null ) )
{
return false;
}
return a.Equals( b );
}
/// <summary>
/// Inequality operator.
/// </summary>
///
/// <param name="a">First object to check.</param>
/// <param name="b">Seconds object to check.</param>
///
/// <returns>Return true if both objects are not equal or false otherwise.</returns>
public static bool operator !=( VideoCapabilities a, VideoCapabilities b )
{
return !( a == b );
}
}
}