// ------------------------------------------------------------------
// DirectX.Capture
//
// History:
// 2003-Jan-24 BL - created
//
// Future Improvements
// - Notify unusual events (disk full, quick logoff) using IMediaEventEx (see AMCap line 1624)
// - Capture stats: IAMDroppedFrames, IQualProp.get_AvgFrameRate
// - Show preview while cued: ICaptureGraphBuilder2.ControlStream lets you stop capture but continue preview
// - Pre-alloc space with ICaptureGraphBuilder2.AllocCapFile(), copy data using ICaptureGraphBuilder2.CopyCaptureFile()
// - Audio preview (why doesn't VirtualDub do audio preview?)
// - Hardware Deinterlacing: "Setting Deinterlace Preferences", or IVMRDeinterlaceControl9
// - Time limit (and TimeRemaining) -> AmCap manually handles the time limit
// - Don't destory filter graph when changing compressors, just remove compressor and add new one
// - Change VideoFormat (NTSC/PAL), I think you need to use IAMVideoDecoder (WDM only)
//
// Copyright (c) 2003 Brian Low
// ------------------------------------------------------------------
using System;
using System.Diagnostics;
using System.Drawing;
using System.IO;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Threading;
using System.Windows.Forms;
using DShowNET;
namespace DirectX.Capture
{
/// <summary>
/// Use the Capture class to capture audio and video to AVI files.
/// </summary>
/// <remarks>
/// This is the core class of the Capture Class Library. The following
/// sections introduce the Capture class and how to use this library.
///
/// <br/><br/>
/// <para><b>Basic Usage</b></para>
///
/// <para>
/// The Capture class only requires a video device and/or audio device
/// to begin capturing. The <see cref="Filters"/> class provides
/// lists of the installed video and audio devices.
/// </para>
/// <code><div style="background-color:whitesmoke;">
/// // Remember to add a reference to DirectX.Capture.dll
/// using DirectX.Capture
/// ...
/// Capture capture = new Capture( Filters.VideoInputDevices[0],
/// Filters.AudioInputDevices[0] );
/// capture.Start();
/// ...
/// capture.Stop();
/// </div></code>
/// <para>
/// This will capture video and audio using the first video and audio devices
/// installed on the system. To capture video only, pass a null as the second
/// parameter of the constructor.
/// </para>
/// <para>
/// The class is initialized to a valid temporary file in the Windows temp
/// folder. To capture to a different file, set the
/// <see cref="Capture.Filename"/> property before you begin
/// capturing. Remember to add DirectX.Capture.dll to
/// your project references.
/// </para>
///
/// <br/>
/// <para><b>Setting Common Properties</b></para>
///
/// <para>
/// The example below shows how to change video and audio settings.
/// Properties such as <see cref="Capture.FrameRate"/> and
/// <see cref="AudioSampleSize"/> allow you to programmatically adjust
/// the capture. Use <see cref="Capture.VideoCaps"/> and
/// <see cref="Capture.AudioCaps"/> to determine valid values for these
/// properties.
/// </para>
/// <code><div style="background-color:whitesmoke;">
/// Capture capture = new Capture( Filters.VideoInputDevices[0],
/// Filters.AudioInputDevices[1] );
/// capture.VideoCompressor = Filters.VideoCompressors[0];
/// capture.AudioCompressor = Filters.AudioCompressors[0];
/// capture.FrameRate = 29.997;
/// capture.FrameSize = new Size( 640, 480 );
/// capture.AudioSamplingRate = 44100;
/// capture.AudioSampleSize = 16;
/// capture.Filename = "C:\MyVideo.avi";
/// capture.Start();
/// ...
/// capture.Stop();
/// </div></code>
/// <para>
/// The example above also shows the use of video and audio compressors. In most
/// cases you will want to use compressors. Uncompressed video can easily
/// consume over a 1GB of disk space per minute. Whenever possible, set
/// the <see cref="Capture.VideoCompressor"/> and <see cref="Capture.AudioCompressor"/>
/// properties as early as possible. Changing them requires the internal filter
/// graph to be rebuilt which often causes most of the other properties to
/// be reset to default values.
/// </para>
///
/// <br/>
/// <para><b>Listing Devices</b></para>
///
/// <para>
/// Use the <see cref="Filters.VideoInputDevices"/> collection to list
/// video capture devices installed on the system.
/// </para>
/// <code><div style="background-color:whitesmoke;">
/// foreach ( Filter f in Filters.VideoInputDevices )
/// {
/// Debug.WriteLine( f.Name );
/// }
/// </div></code>
/// The <see cref="Filters"/> class also provides collections for audio
/// capture devices, video compressors and audio compressors.
///
/// <br/>
/// <para><b>Preview</b></para>
///
/// <para>
/// Video preview is controled with the <see cref="Capture.PreviewWindow"/>
/// property. Setting this property to a visible control will immediately
/// begin preview. Set to null to stop the preview.
/// </para>
/// <code><div style="background-color:whitesmoke;">
/// // Enable preview
/// capture.PreviewWindow = myPanel;
/// // Disable preview
/// capture.PreviewWindow = null;
/// </div></code>
/// <para>
/// The control used must have a window handle (HWND), good controls to
/// use are the Panel or the form itself.
/// </para>
/// <para>
/// Retrieving or changing video/audio settings such as FrameRate,
/// FrameSize, AudioSamplingRate, and AudioSampleSize will cause
/// the preview window to flash. This is beacuse the preview must be
/// temporarily stopped. Disable the preview if you need to access
/// several properties at the same time.
/// </para>
///
/// <br/>
/// <para><b>Property Pages</b></para>
///
/// <para>
/// Property pages exposed by the devices and compressors are
/// available through the <see cref="Capture.PropertyPages"/>
/// collection.
/// </para>
/// <code><div style="background-color:whitesmoke;">
/// // Display the first property page
/// capture.PropertyPages[0].Show();
/// </div></code>
/// <para>
/// The property pages will often expose more settings than
/// the Capture class does directly. Some examples are brightness,
/// color space, audio balance and bass boost. The disadvantage
/// to using the property pages is the user's choices cannot be
/// saved and later restored. The exception to this is the video
/// and audio compressor property pages. Most compressors support
/// the saving and restoring state, see the
/// <see cref="PropertyPage.State"/> property for more information.
/// </para>
/// <para>
/// Changes made in the property page will be reflected
/// immediately in the Capture class properties (e.g. Capture.FrameSize).
/// However, the reverse is not always true. A change made directly to
/// FrameSize, for example, may not be reflected in the associated
/// property page. Fortunately, the filter will use requested FrameSize
/// even though the property page shows otherwise.
/// </para>
///
/// <br/>
/// <para><b>Saving and Restoring Settings</b></para>
///
/// <para>
/// To save the user's choice of devices and compressors,
/// save <see cref="Filter.MonikerString"/> and user it later
/// to recreate the Filter object.
/// </para>
/// <para>
/// To save a user's choices from a property page use
/// <see cref="PropertyPage.State"/>. However, only the audio
/// and video compressor property pages support this.
/// </para>
/// <para>
/// The last items to save are the video and audio settings such
/// as FrameSize and AudioSamplingRate. When restoring, remember
/// to restore these properties after setting the video and audio
/// compressors.
/// </para>
/// <code><div style="background-color:whitesmoke;">
/// // Disable preview
/// capture.PreviewWindow = null;
///
/// // Save settings
/// string videoDevice = capture.VideoDevice.MonikerString;
/// string audioDevice = capture.AudioDevice.MonikerString;
/// string videoCompressor = capture.VideoCompressor.MonikerString;
/// string audioCompressor = capture.AudioCompressor.MonikerString;
/// double frameRate = capture.FrameRate;
/// Size frameSize = capture.FrameSize;
/// short audioChannels = capture.AudioChannels;
/// short audioSampleSize = capture.AudioSampleSize;
/// int audioSamplingRate = capture.AudioSamplingRate;
/// ArrayList pages = new ArrayList();
/// foreach ( PropertyPage p in capture.PropertyPages )
/// {
/// if ( p.SupportsPersisting )
/// pages.Add( p.State );
/// }
///
///
/// // Restore settings
/// Capture capture = new Capture( new Filter( videoDevice),
/// new Filter( audioDevice) );
/// capture.VideoCompressor = new Filter( videoCompressor );
/// capture.AudioCompressor = new Filter( audioCompressor );
/// capture.FrameRate = frameRate;
/// capture.FrameSize = frameSize;
/// capture.AudioChannels = audioChannels;
/// capture.AudioSampleSize = audioSampleSize;
/// capture.AudioSamplingRate = audioSamplingRate;
/// foreach ( PropertyPage p in capture.PropertyPages )
/// {
/// if ( p.SupportsPersisting )
/// {
/// p.State = (byte[]) pages[0]
/// pages.RemoveAt( 0 );
/// }
/// }
/// // Enable preview
/// capture.PreviewWindow = myPanel;
/// </div></code>
///
/// <br/>
/// <para><b>TV Tuner</b></para>
///
/// <para>
/// To access the TV Tuner, use the <see cref="Capture.Tuner"/> property.
/// If the device does not have a TV tuner, this property will be null.
/// See <see cref="DirectX.Capture.Tuner.Channel"/>,
/// <see cref="DirectX.Capture.Tuner.InputType"/> and
/// <see cref="DirectX.Capture.Tuner.SignalPresent"/>
/// for more information.
/// </para>
/// <code><div style="background-color:whitesmoke;">
/// // Change to channel 5
/// capture.Tuner.Channel = 5;
/// </div></code>
///
/// <br/>
/// <para><b>Troubleshooting</b></para>
///
/// <para>
/// This class library uses COM Interop to access the full
/// capabilities of DirectShow, so if there is another
/// application that can successfully use a hardware device
/// then it should be possible to modify this class library
/// to use the device.
/// </para>
/// <para>
/// Try the <b>AMCap</b> sample from the DirectX SDK
/// (DX9\Samples\C++\DirectShow\Bin\AMCap.exe) or
/// <b>Virtual VCR</b> from http://www.DigTV.ws
/// </para>
///
/// <br/>
/// <para><b>Credits</b></para>
///
/// <para>
/// This class library would not be possible without the
/// DShowNET project by NETMaster:
/// http://www.codeproject.com/useritems/directshownet.asp
/// </para>
/// <para>
/// Documentation is generated by nDoc available at
/// http://ndoc.sourceforge.net
/// </para>
///
/// <br/>
/// <para><b>Feedback</b></para>
///
/// Feel free to send comments and questions to me at
/// mportobello@hotmail.com. If the the topic may be of interest
/// to others, post your question on the www.codeproject.com
/// page for DirectX.Capture.
/// </remarks>
public class Capture
{
// ------------------ Private Enumerations --------------------
/// <summary> Possible states of the interal filter graph </summary>
protected enum GraphState
{
Null, // No filter graph at all
Created, // Filter graph created with device filters added
Rendered, // Filter complete built, ready to run (possibly previewing)
Capturing // Filter is capturing
}
// ------------------ Public Properties --------------------
/// <summary> Is the class currently capturing. Read-only. </summary>
public bool Capturing { get { return( graphState==GraphState.Capturing ); } }
/// <summary> Has the class been cued to begin capturing. Read-only. </summary>
public bool Cued { get { return( isCaptureRendered && graphState==GraphState.Rendered ); } }
/// <summary> Is the class currently stopped. Read-only. </summary>
public bool Stopped { get { return( graphState!=GraphState.Capturing ); } }
/// <summary>
/// Name of file to capture to. Initially set to
/// a valid temporary file.
/// </summary>
/// <remarks>
/// If the file does not exist, it will be created. If it does
/// exist, it will be overwritten. An overwritten file will
/// not be shortened if the captured data is smaller than the
/// original file. The file will be valid, it will just contain
/// extra, unused, data after the audio/video data.
///
/// <para>
/// A future version of this class will provide a method to copy
/// only the valid audio/video data to a new file. </para>
///
/// <para>
/// This property cannot be changed while capturing or cued. </para>
/// </remarks>
public string Filename
{
get { return( filename ); }
set
{
assertStopped();
if ( Cued )
throw new InvalidOperationException( "The Filename cannot be changed once cued. Use Stop() before changing the filename." );
filename = value;
if ( fileWriterFilter != null )
{
string s;
AMMediaType mt = new AMMediaType();
int hr = fileWriterFilter.GetCurFile( out s, mt );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
if ( mt.formatSize > 0 )
Marshal.FreeCoTaskMem( mt.formatPtr );
hr = fileWriterFilter.SetFileName( filename, mt );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
}
}
}
/// <summary>
/// The control that will host the preview window.
/// </summary>
/// <remarks>
/// Setting this property will begin video preview
/// immediately. Set this property after setting all
/// other properties to avoid unnecessary changes
/// to the internal filter graph (some properties like
/// FrameSize require the internal filter graph to be
/// stopped and disconnected before the property
/// can be retrieved or set).
///
/// <para>
/// To stop video preview, set this property to null. </para>
/// </remarks>
public Control PreviewWindow
{
get { return( previewWindow ); }
set
{
assertStopped();
derenderGraph();
previewWindow = value;
wantPreviewRendered = ( ( previewWindow != null ) && ( videoDevice != null ) );
renderGraph();
startPreviewIfNeeded();
}
}
/// <summary>
/// The capabilities of the video device.
/// </summary>
/// <remarks>
/// It may be required to cue the capture (see <see cref="Cue"/>)
/// before all capabilities are correctly reported. If you
/// have such a device, the developer would be interested to
/// hear from you.
///
/// <para>
/// The information contained in this property is retrieved and
/// cached the first time this property is accessed. Future
/// calls to this property use the cached results. This was done
/// for performance. </para>
///
/// <para>
/// However, this means <b>you may get different results depending
/// on when you access this property first</b>. If you are experiencing
/// problems, try accessing the property immediately after creating
/// the Capture class or immediately after setting the video and
/// audio compressors. Also, inform the developer. </para>
/// </remarks>
public VideoCapabilities VideoCaps
{
get
{
if ( videoCaps == null )
{
if ( videoStreamConfig != null )
{
try
{
videoCaps = new VideoCapabilities( videoStreamConfig );
}
catch ( Exception ex ) { Debug.WriteLine( "VideoCaps: unable to create videoCaps." + ex.ToString() ); }
}
}
return( videoCaps );
}
}
/// <summary>
/// The capabilities of the audio device.
/// </summary>
/// <remarks>
/// It may be required to cue the capture (see <see cref="Cue"/>)
/// before all capabilities are correctly reported. If you
/// have such a device, the developer would be interested to
/// hear from you.
///
/// <para>
/// The information contained in this property is retrieved and
/// cached the first time this property is accessed. Future
/// calls to this property use the cached results. This was done
/// for performance. </para>
///
/// <para>
/// However, this means <b>you may get different results depending
/// on when you access this property first</b>. If you are experiencing
/// problems, try accessing the property immediately after creating
/// the Capture class or immediately after setting the video and
/// audio compressors. Also, inform the developer. </para>
/// </remarks>
public AudioCapabilities AudioCaps
{
get
{
if ( audioCaps == null )
{
if ( audioStreamConfig != null )
{
try
{
audioCaps = new AudioCapabilities( audioStreamConfig );
}
catch ( Exception ex ) { Debug.WriteLine( "AudioCaps: unable to create audioCaps." + ex.ToString() ); }
}
}
return( audioCaps );
}
}
/// <summary>
/// The video capture device filter. Read-only. To use a different
/// device, dispose of the current Capture instance and create a new
/// instance with the desired device.
/// </summary>
public Filter VideoDevice { get { return( videoDevice ); } }
/// <summary>
/// The audio capture device filter. Read-only. To use a different
/// device, dispose of the current Capture instance and create a new
/// instance with the desired device.
/// </summary>
public Filter AudioDevice { get { return( audioDevice ); } }
/// <summary>
/// The video compression filter. When this property is changed
/// the internal filter graph is rebuilt. This means that some properties
/// will be reset. Set this property as early as possible to avoid losing
/// changes. This property cannot be changed while capturing.
/// </summary>
public Filter VideoCompressor {
get { return( videoCompressor ); }
set
{
assertStopped();
destroyGraph();
videoCompressor = value;
renderGraph();
startPreviewIfNeeded();
}
}
/// <summary>
/// The audio compression filter.
/// </summary>
/// <remarks>
/// When this property is changed
/// the internal filter graph is rebuilt. This means that some properties
/// will be reset. Set this property as early as possible to avoid losing
/// changes. This property cannot be changed while capturing.
/// </remarks>
public Filter AudioCompressor
{
get { return( audioCompressor ); }
set
{
assertStopped();
destroyGraph();
audioCompressor = value;
renderGraph();
startPreviewIfNeeded();
}
}
/// <summary>
/// The current video source. Use Capture.VideoSources to
/// list available sources. Set to null to disable all
/// sources (mute).
/// </summary>
public Source VideoSource
{
get { return( VideoSources.CurrentSource ); }
set { VideoSources.CurrentSource = value; }
}
/// <summary>
/// The current audio source. Use Capture.AudioSources to
/// list available sources. Set to null to disable all
/// sources (mute).
/// </summary>
public Source AudioSource
{
get { return( AudioSources.CurrentSource ); }
set { AudioSources.CurrentSource = value; }
}
/// <summary>
/// Collection of available video sources/physical connectors
/// on the current video device.
/// </summary>
/// <remarks>
/// In most cases, if the device has only one source,
/// this collection will be empty.
///
/// <para>
/// The information contained in this property is retrieved and
/// cached the first time this property is accessed. Future
/// calls to this property use the cached results. This was done
/// for performance. </para>
///
/// <para>
/// However, this means <b>you may get different results depending
/// on when you access this property first</b>. If you are experiencing
/// problems, try accessing the property immediately after creating
/// the Capture class or immediately after setting the video and
/// audio compressors. Also, inform the developer. </para>
/// </remarks>
public SourceCollection VideoSources
{
get
{
if ( videoSources == null )
{
try
{
if ( videoDevice != null )
videoSources = new SourceCollection( captureGraphBuilder, videoDeviceFilter, true );
else
videoSources = new SourceCollection();
}
catch ( Exception ex ) { Debug.WriteLine( "VideoSources: unable to create VideoSources." + ex.ToString() ); }
}
return ( videoSources );
}
}
/// <summary>
/// Collection of available audio sources/physical connectors
/// on the current audio device.
/// </summary>
/// <remarks>
/// In most cases, if the device has only one source,
/// this collection will be empty. For audio
/// there are 2 different methods for enumerating audio sources
/// an audio crossbar (usually TV tuners?) or an audio mixer
/// (usually sound cards?). This class will first look for an
/// audio crossbar. If no sources or only one source is available
/// on the crossbar, this class will then look for an audio mixer.
/// This class does not support both methods.
///
/// <para>
/// The information contained in this property is retrieved and
/// cached the first time this property is accessed. Future
/// calls to this property use the cached results. This was done
/// for performance. </para>
///
/// <para>
/// However, this means <b>you may get different results depending
/// on when you access this property first</b>. If you are experiencing
/// problems, try accessing the property immediately after creating
/// the Capture class or immediately after setting the video and
/// audio compressors. Also, inform the developer. </para>
/// </remarks>
public SourceCollection AudioSources
{
get
{
if ( audioSources == null )
{
try
{
if ( audioDevice != null )
audioSources = new SourceCollection( captureGraphBuilder, audioDeviceFilter, false );
else
audioSources = new SourceCollection();
}
catch ( Exception ex ) { Debug.WriteLine( "AudioSources: unable to create AudioSources." + ex.ToString() ); }
}
return ( audioSources );
}
}
/// <summary>
/// Available property pages.
/// </summary>
/// <remarks>
/// These are property pages exposed by the DirectShow filters.
/// These property pages allow users modify settings on the
/// filters directly.
///
/// <para>
/// The information contained in this property is retrieved and
/// cached the first time this property is accessed. Future
/// calls to this property use the cached results. This was done
/// for performance. </para>
///
/// <para>
/// However, this means <b>you may get different results depending
/// on when you access this property first</b>. If you are experiencing
/// problems, try accessing the property immediately after creating
/// the Capture class or immediately after setting the video and
/// audio compressors. Also, inform the developer. </para>
/// </remarks>
public PropertyPageCollection PropertyPages
{
get
{
if ( propertyPages == null )
{
try
{
propertyPages = new PropertyPageCollection(
captureGraphBuilder,
videoDeviceFilter, audioDeviceFilter,
videoCompressorFilter, audioCompressorFilter,
VideoSources, AudioSources );
}
catch ( Exception ex ) { Debug.WriteLine( "PropertyPages: unable to get property pages." + ex.ToString() ); }
}
return( propertyPages );
}
}
/// <summary>
/// The TV Tuner or null if the current video device
/// does not have a TV Tuner.
/// </summary>
public Tuner Tuner { get { return( tuner ); } }
/// <summary>
/// Gets and sets the frame rate used to capture video.
/// </summary>
/// <remarks>
/// Common frame rates: 24 fps for film, 25 for PAL, 29.997
/// for NTSC. Not all NTSC capture cards can capture at
/// exactly 29.997 fps. Not all frame rates are supported.
/// When changing the frame rate, the closest supported
/// frame rate will be used.
///
/// <para>
/// Not all devices support getting/setting this property.
/// If this property is not supported, accessing it will
/// throw and exception. </para>
///
/// <para>
/// This property cannot be changed while capturing. Changing
/// this property while preview is enabled will cause some
/// fickering while the internal filter graph is partially
/// rebuilt. Changing this property while cued will cancel the
/// cue. Call Cue() again to re-cue the capture. </para>
/// </remarks>
public double FrameRate
{
get
{
long avgTimePerFrame = (long) getStreamConfigSetting( videoStreamConfig, "AvgTimePerFrame" );
return( (double) 10000000 / avgTimePerFrame );
}
set
{
long avgTimePerFrame = (long) ( 10000000 / value );
setStreamConfigSetting( videoStreamConfig, "AvgTimePerFrame", avgTimePerFrame );
}
}
/// <summary>
/// Gets and sets the frame size used to capture video.
/// </summary>
/// <remarks>
/// To change the frame size, assign a new Size object
/// to this property <code>capture.Size = new Size( w, h );</code>
/// rather than modifying the size in place
/// (capture.Size.Width = w;). Not all frame
/// rates are supported.
///
/// <para>
/// Not all devices support getting/setting this property.
/// If this property is not supported, accessing it will
/// throw and exception. </para>
///
/// <para>
/// This property cannot be changed while capturing. Changing
/// this property while preview is enabled will cause some
/// fickering while the internal filter graph is partially
/// rebuilt. Changing this property while cued will cancel the
/// cue. Call Cue() again to re-cue the capture. </para>
/// </remarks>
public Size FrameSize
{
get
{
BitmapInfoHeader bmiHeader;
bmiHeader = (BitmapInfoHeader) getStreamConfigSetting( videoStreamConfig, "BmiHeader" );
Size size = new Size( bmiHeader.Width, bmiHeader.Height );
return( size );
}
set
{
BitmapInfoHeader bmiHeader;
bmiHeader = (BitmapInfoHeader) getStreamConfigSetting( videoStreamConfig, "BmiHeader" );
bmiHeader.Width = value.Width;
bmiHeader.Height = value.Height;
setStreamConfigSetting( videoStreamConfig, "BmiHeader", bmiHeader );
}
}
/// <summary>
/// Get or set the number of channels in the waveform-audio data.
/// </summary>
/// <remarks>
/// Monaural data uses one channel and stereo data uses two channels.
///
/// <para>
/// Not all devices support getting/setting this property.
/// If this property is not supported, accessing it will
/// throw and exception. </para>
///
/// <para>
/// This property cannot be changed while capturing. Changing
/// this property while preview is enabled will cause some
/// fickering while the internal filter graph is partially
/// rebuilt. Changing this property while cued will cancel the
/// cue. Call Cue() again to re-cue the capture. </para>
/// </remarks>
public short AudioChannels
{
get
{
short audioChannels = (short) getStreamConfigSetting( audioStreamConfig, "nChannels" );
return( audioChannels );
}
set
{
setStreamConfigSetting( audioStreamConfig, "nChannels", value );
}
}
/// <summary>
/// Get or set the number of audio samples taken per second.
/// </summary>
/// <remarks>
/// Common sampling rates are 8.0 kHz, 11.025 kHz, 22.05 kHz, and
/// 44.1 kHz. Not all sampling rates are supported.
///
/// <para>
/// Not all devices support getting/setting this property.
/// If this property is not supported, accessing it will
/// throw and exception. </para>
///
/// <para>
/// This property cannot be changed while capturing. Changing
/// this property while preview is enabled will cause some
/// fickering while the internal filter graph is partially
/// rebuilt. Changing this property while cued will cancel the
/// cue. Call Cue() again to re-cue the capture. </para>
/// </remarks>
public int AudioSamplingRate
{
get
{
int samplingRate = (int) getStreamConfigSetting( audioStreamConfig, "nSamplesPerSec" );
return( samplingRate );
}
set
{
setStreamConfigSetting( audioStreamConfig, "nSamplesPerSec", value );
}
}
/// <summary>
/// Get or set the number of bits recorded per sample.
/// </summary>
/// <remarks>
/// Common sample sizes are 8 bit and 16 bit. Not all
/// samples sizes are supported.
///
/// <para>
/// Not all devices support getting/setting this property.
/// If this property is not supported, accessing it will
/// throw and exception. </para>
///
/// <para>
/// This property cannot be changed while capturing. Changing
/// this property while preview is enabled will cause some
/// fickering while the internal filter graph is partially
/// rebuilt. Changing this property while cued will cancel the
/// cue. Call Cue() again to re-cue the capture. </para>
/// </remarks>
public short AudioSampleSize
{
get
{
short sampleSize = (short) getStreamConfigSetting( audioStreamConfig, "wBitsPerSample" );
return( sampleSize );
}
set
{
setStreamConfigSetting( audioStreamConfig, "wBitsPerSample", value );
}
}
// --------------------- Events ----------------------
/// <summary> Fired when a capture is completed (manually or automatically). </summary>
public event EventHandler CaptureComplete;
// ------------- Protected/private Properties --------------
protected GraphState graphState = GraphState.Null; // State of the internal filter graph
protected bool isPreviewRendered = false; // When graphState==Rendered, have we rendered the preview stream?
protected bool isCaptureRendered = false; // When graphState==Rendered, have we rendered the capture stream?
protected bool wantPreviewRendered = false; // Do we need the preview stream rendered (VideoDevice and PreviewWindow != null)
protected bool wantCaptureRendered = false; // Do we need the capture stream rendered
protected int rotCookie = 0; // Cookie into the Running Object Table
protected Filter videoDevice = null; // Property Backer: Video capture device filter
protected Filter audioDevice = null; // Property Backer: Audio capture device filter
protected Filter videoCompressor = null; // Property Backer: Video compression filter
protected Filter audioCompressor = null; // Property Backer: Audio compression filter
protected string filename = ""; // Property Backer: Name of file to capture to
protected Control previewWindow = null; // Property Backer: Owner control for preview
protected VideoCapabilities videoCaps = null; // Property Backer: capabilities of video device
protected AudioCapabilities audioCaps = null; // Property Backer: capabilities of audio device
protected SourceCollection videoSources = null; // Property Backer: list of physical video sources
protected SourceCollection audioSources = null; // Property Backer: list of physical audio sources
protected PropertyPageCollection propertyPages = null; // Property Backer: list of property pages exposed by filters
protected Tuner tuner = null; // Property Backer: TV Tuner
protected IGraphBuilder graphBuilder; // DShow Filter: Graph builder
protected IMediaControl mediaControl; // DShow Filter: Start/Stop the filter graph -> copy of graphBuilder
protected IVideoWindow videoWindow; // DShow Filter: Control preview window -> copy of graphBuilder
protected ICaptureGraphBuilder2 captureGraphBuilder = null; // DShow Filter: building graphs for capturing video
protected IAMStreamConfig videoStreamConfig = null; // DShow Filter: configure frame rate, size
protected IAMStreamConfig audioStreamConfig = null; // DShow Filter: configure sample rate, sample size
protected IBaseFilter videoDeviceFilter = null; // DShow Filter: selected video device
protected IBaseFilter videoCompressorFilter = null; // DShow Filter: selected video compressor
protected IBaseFilter audioDeviceFilter = null; // DShow Filter: selected audio device
protected IBaseFilter audioCompressorFilter = null; // DShow Filter: selected audio compressor
protected IBaseFilter muxFilter = null; // DShow Filter: multiplexor (combine video and audio streams)
protected IFileSinkFilter fileWriterFilter = null; // DShow Filter: file writer
// ------------- Constructors/Destructors --------------
/// <summary>
/// Create a new Capture object.
/// videoDevice and audioDevice can be null if you do not
/// wish to capture both audio and video. However at least
/// one must be a valid device. Use the <see cref="Filters"/>
/// class to list available devices.
/// </summary>
public Capture(Filter videoDevice, Filter audioDevice)
{
if ( videoDevice == null && audioDevice == null )
throw new ArgumentException( "The videoDevice and/or the audioDevice parameter must be set to a valid Filter.\n" );
this.videoDevice = videoDevice;
this.audioDevice = audioDevice;
this.Filename = getTempFilename();
createGraph();
}
/// <summary> Destructor. Dispose of resources. </summary>
~Capture()
{
Dispose();
}
// --------------------- Public Methods -----------------------
/// <summary>
/// Prepare for capturing. Use this method when capturing
/// must begin as quickly as possible.
/// </summary>
/// <remarks>
/// This will create/overwrite a zero byte file with
/// the name set in the Filename property.
///
/// <para>
/// This will disable preview. Preview will resume
/// once capture begins. This problem can be fixed
/// if someone is willing to make the change. </para>
///
/// <para>
/// This method is optional. If Cue() is not called,
/// Start() will call it before capturing. This method
/// cannot be called while capturing. </para>
/// </remarks>
public void Cue()
{
assertStopped();
// We want the capture stream rendered
wantCaptureRendered = true;
// Re-render the graph (if necessary)
renderGraph();
// Pause the graph
int hr = mediaControl.Pause();
if ( hr != 0 ) Marshal.ThrowExceptionForHR( hr );
}
/// <summary> Begin capturing. </summary>
public void Start()
{
assertStopped();
// We want the capture stream rendered
wantCaptureRendered = true;
// Re-render the graph (if necessary)
renderGraph();
// Start the filter graph: begin capturing
int hr = mediaControl.Run();
if ( hr != 0 ) Marshal.ThrowExceptionForHR( hr );
// Update the state
graphState = GraphState.Capturing;
}
/// <summary>
/// Stop the current capture capture. If there is no
/// current capture, this method will succeed.
/// </summary>
public void Stop()
{
wantCaptureRendered = false;
// Stop the graph if it is running
// If we have a preview running we should only stop the
// capture stream. However, if we have a preview stream
// we need to re-render the graph anyways because we
// need to get rid of the capture stream. To re-render
// we need to stop the entire graph
if ( mediaControl != null )
{
mediaControl.Stop();
}
// Update the state
if ( graphState == GraphState.Capturing )
{
graphState = GraphState.Rendered;
if ( CaptureComplete != null )
CaptureComplete( this, null );
}
// So we destroy the capture stream IF
// we need a preview stream. If we don't
// this will leave the graph as it is.
try { renderGraph(); } catch {}
try { startPreviewIfNeeded(); } catch {}
}
/// <summary>
/// Calls Stop, releases all references. If a capture is in progress
/// it will be stopped, but the CaptureComplete event will NOT fire.
/// </summary>
public void Dispose()
{
wantPreviewRendered = false;
wantCaptureRendered = false;
CaptureComplete = null;
try { destroyGraph(); } catch {}
if ( videoSources != null )
videoSources.Dispose(); videoSources = null;
if ( audioSources != null )
audioSources.Dispose(); audioSources = null;
}
// --------------------- Private Methods -----------------------
/// <summary>
/// Create a new filter graph and add filters (devices, compressors,
/// misc), but leave the filters unconnected. Call renderGraph()
/// to connect the filters.
/// </summary>
protected void createGraph()
{
Guid cat;
Guid med;
int hr;
// Ensure required properties are set
if ( videoDevice == null && audioDevice == null )
throw new ArgumentException( "The video and/or audio device have not been set. Please set one or both to valid capture devices.\n" );
// Skip if we are already created
if ( (int)graphState < (int)GraphState.Created )
{
// Garbage collect, ensure that previous filters are released
GC.Collect();
// Make a new filter graph
graphBuilder = (IGraphBuilder) Activator.CreateInstance( Type.GetTypeFromCLSID( Clsid.FilterGraph, true ) );
// Get the Capture Graph Builder
Guid clsid = Clsid.CaptureGraphBuilder2;
Guid riid = typeof(ICaptureGraphBuilder2).GUID;
captureGraphBuilder = (ICaptureGraphBuilder2) DsBugWO.CreateDsInstance( ref clsid, ref riid );
// Link the CaptureGraphBuilder to the filter graph
hr = captureGraphBuilder.SetFiltergraph( graphBuilder );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
// Add the graph to the Running Object Table so it can be
// viewed with GraphEdit
#if DEBUG
DsROT.AddGraphToRot( graphBuilder, out rotCookie );
#endif
// Get the video device and add it to the filter graph
if ( VideoDevice != null )
{
videoDeviceFilter = (IBaseFilter) Marshal.BindToMoniker( VideoDevice.MonikerString );
hr = graphBuilder.AddFilter( videoDeviceFilter, "Video Capture Device" );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
}
// Get the audio device and add it to the filter graph
if ( AudioDevice != null )
{
audioDeviceFilter = (IBaseFilter) Marshal.BindToMoniker( AudioDevice.MonikerString );
hr = graphBuilder.AddFilter( audioDeviceFilter, "Audio Capture Device" );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
}
// Get the video compressor and add it to the filter graph
if ( VideoCompressor != null )
{
videoCompressorFilter = (IBaseFilter) Marshal.BindToMoniker( VideoCompressor.MonikerString );
hr = graphBuilder.AddFilter( videoCompressorFilter, "Video Compressor" );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
}
// Get the audio compressor and add it to the filter graph
if ( AudioCompressor != null )
{
audioCompressorFilter = (IBaseFilter) Marshal.BindToMoniker( AudioCompressor.MonikerString );
hr = graphBuilder.AddFilter( audioCompressorFilter, "Audio Compressor" );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
}
// Retrieve the stream control interface for the video device
// FindInterface will also add any required filters
// (WDM devices in particular may need additional
// upstream filters to function).
// Try looking for an interleaved media type
object o;
cat = PinCategory.Capture;
med = MediaType.Interleaved;
Guid iid = typeof(IAMStreamConfig).GUID;
hr = captureGraphBuilder.FindInterface(
ref cat, ref med, videoDeviceFilter, ref iid, out o );
if ( hr != 0 )
{
// If not found, try looking for a video media type
med = MediaType.Video;
hr = captureGraphBuilder.FindInterface(
ref cat, ref med, videoDeviceFilter, ref iid, out o );
if ( hr != 0 )
o = null;
}
videoStreamConfig = o as IAMStreamConfig;
// Retrieve the stream control interface for the audio device
o = null;
cat = PinCategory.Capture;
med = MediaType.Audio ;
iid = typeof(IAMStreamConfig).GUID;
hr = captureGraphBuilder.FindInterface(
ref cat, ref med, audioDeviceFilter, ref iid, out o );
if ( hr != 0 )
o = null;
audioStreamConfig = o as IAMStreamConfig;
// Retreive the media control interface (for starting/stopping graph)
mediaControl = (IMediaControl) graphBuilder;
// Reload any video crossbars
if ( videoSources != null ) videoSources.Dispose(); videoSources = null;
// Reload any audio crossbars
if ( audioSources != null ) audioSources.Dispose(); audioSources = null;
// Reload any property pages exposed by filters
if ( propertyPages != null ) propertyPages.Dispose(); propertyPages = null;
// Reload capabilities of video device
videoCaps = null;
// Reload capabilities of video device
audioCaps = null;
// Retrieve TV Tuner if available
o = null;
cat = PinCategory.Capture;
med = MediaType.Interleaved;
iid = typeof(IAMTVTuner).GUID;
hr = captureGraphBuilder.FindInterface(
ref cat, ref med, videoDeviceFilter, ref iid, out o );
if ( hr != 0 )
{
med = MediaType.Video ;
hr = captureGraphBuilder.FindInterface(
ref cat, ref med, videoDeviceFilter, ref iid, out o );
if ( hr != 0 )
o = null;
}
IAMTVTuner t = o as IAMTVTuner;
if ( t != null )
tuner = new Tuner( t );
/*
// ----------- VMR 9 -------------------
//## check out samples\inc\vmrutil.h :: RenderFileToVMR9
IBaseFilter vmr = null;
if ( ( VideoDevice != null ) && ( previewWindow != null ) )
{
vmr = (IBaseFilter) Activator.CreateInstance( Type.GetTypeFromCLSID( Clsid.VideoMixingRenderer9, true ) );
hr = graphBuilder.AddFilter( vmr, "VMR" );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
IVMRFilterConfig9 vmrFilterConfig = (IVMRFilterConfig9) vmr;
hr = vmrFilterConfig.SetRenderingMode( VMRMode9.Windowless );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
IVMRWindowlessControl9 vmrWindowsless = (IVMRWindowlessControl9) vmr;
hr = vmrWindowsless.SetVideoClippingWindow( previewWindow.Handle );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
}
//-------------------------------------------
// ---------- SmartTee ---------------------
IBaseFilter smartTeeFilter = (IBaseFilter) Activator.CreateInstance( Type.GetTypeFromCLSID( Clsid.SmartTee, true ) );
hr = graphBuilder.AddFilter( smartTeeFilter, "Video Smart Tee" );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
// Video -> SmartTee
cat = PinCategory.Capture;
med = MediaType.Video;
hr = captureGraphBuilder.RenderStream( ref cat, ref med, videoDeviceFilter, null, smartTeeFilter );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
// smarttee -> mux
cat = PinCategory.Capture;
med = MediaType.Video;
hr = captureGraphBuilder.RenderStream( ref cat, ref med, smartTeeFilter, null, muxFilter );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
// smarttee -> vmr
cat = PinCategory.Preview;
med = MediaType.Video;
hr = captureGraphBuilder.RenderStream( ref cat, ref med, smartTeeFilter, null, vmr );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
// -------------------------------------
*/
// Update the state now that we are done
graphState = GraphState.Created;
}
}
/// <summary>
/// Connects the filters of a previously created graph
/// (created by createGraph()). Once rendered the graph
/// is ready to be used. This method may also destroy
/// streams if we have streams we no longer want.
/// </summary>
protected void renderGraph()
{
Guid cat;
Guid med;
int hr;
bool didSomething = false;
const int WS_CHILD = 0x40000000;
const int WS_CLIPCHILDREN = 0x02000000;
const int WS_CLIPSIBLINGS = 0x04000000;
assertStopped();
// Ensure required properties set
if ( filename == null )
throw new ArgumentException( "The Filename property has not been set to a file.\n" );
// Stop the graph
if ( mediaControl != null )
mediaControl.Stop();
// Create the graph if needed (group should already be created)
createGraph();
// Derender the graph if we have a capture or preview stream
// that we no longer want. We can't derender the capture and
// preview streams seperately.
// Notice the second case will leave a capture stream intact
// even if we no longer want it. This allows the user that is
// not using the preview to Stop() and Start() without
// rerendering the graph.
if ( !wantPreviewRendered && isPreviewRendered )
derenderGraph();
if ( !wantCaptureRendered && isCaptureRendered )
if ( wantPreviewRendered )
derenderGraph();
// Render capture stream (only if necessary)
if ( wantCaptureRendered && !isCaptureRendered )
{
// Render the file writer portion of graph (mux -> file)
Guid mediaSubType = MediaSubType.Avi;
hr = captureGraphBuilder.SetOutputFileName( ref mediaSubType, Filename, out muxFilter, out fileWriterFilter );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
// Render video (video -> mux)
if ( VideoDevice != null )
{
// Try interleaved first, because if the device supports it,
// it's the only way to get audio as well as video
cat = PinCategory.Capture;
med = MediaType.Interleaved;
hr = captureGraphBuilder.RenderStream( ref cat, ref med, videoDeviceFilter, videoCompressorFilter, muxFilter );
if( hr < 0 )
{
med = MediaType.Video;
hr = captureGraphBuilder.RenderStream( ref cat, ref med, videoDeviceFilter, videoCompressorFilter, muxFilter );
if ( hr == -2147220969 ) throw new DeviceInUseException( "Video device", hr );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
}
}
// Render audio (audio -> mux)
if ( AudioDevice != null )
{
cat = PinCategory.Capture;
med = MediaType.Audio;
hr = captureGraphBuilder.RenderStream( ref cat, ref med, audioDeviceFilter, audioCompressorFilter, muxFilter );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
}
isCaptureRendered = true;
didSomething = true;
}
// Render preview stream (only if necessary)
if ( wantPreviewRendered && !isPreviewRendered )
{
// Render preview (video -> renderer)
cat = PinCategory.Preview;
med = MediaType.Video;
hr = captureGraphBuilder.RenderStream( ref cat, ref med, videoDeviceFilter, null, null );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
// Get the IVideoWindow interface
videoWindow = (IVideoWindow) graphBuilder;
// Set the video window to be a child of the main window
hr = videoWindow.put_Owner( previewWindow.Handle );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
// Set video window style
hr = videoWindow.put_WindowStyle( WS_CHILD | WS_CLIPCHILDREN | WS_CLIPSIBLINGS);
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
// Position video window in client rect of owner window
previewWindow.Resize += new EventHandler( onPreviewWindowResize );
onPreviewWindowResize( this, null );
// Make the video window visible, now that it is properly positioned
hr = videoWindow.put_Visible( DsHlp.OATRUE );
if( hr < 0 ) Marshal.ThrowExceptionForHR( hr );
isPreviewRendered = true;
didSomething = true;
}
if ( didSomething )
graphState = GraphState.Rendered;
}
/// <summary>
/// Setup and start the preview window if the user has
/// requested it (by setting PreviewWindow).
/// </summary>
protected void startPreviewIfNeeded()
{
// Render preview
if ( wantPreviewRendered && isPreviewRendered && !isCaptureRendered )
{
// Run the graph (ignore errors)
// We can run the entire graph becuase the capture
// stream should not be rendered (and that is enforced
// in the if statement above)
mediaControl.Run();
}
}
/// <summary>
/// Disconnect and remove all filters except the device
/// and compressor filters. This is the opposite of
/// renderGraph(). Soem properties such as FrameRate
/// can only be set when the device output pins are not
/// connected.
/// </summary>
protected void derenderGraph()
{
// Stop the graph if it is running (ignore errors)
if ( mediaControl != null )
mediaControl.Stop();
// Free the preview window (ignore errors)
if ( videoWindow != null )
{
videoWindow.put_Visible( DsHlp.OAFALSE );
videoWindow.put_Owner( IntPtr.Zero );
videoWindow = null;
}
// Remove the Resize event handler
if ( PreviewWindow != null )
previewWindow.Resize -= new EventHandler( onPreviewWindowResize );
if ( (int)graphState >= (int)GraphState.Rendered )
{
// Update the state
graphState = GraphState.Created;
isCaptureRendered = false;
isPreviewRendered = false;
// Disconnect all filters downstream of the
// video and audio devices. If we have a compressor
// then disconnect it, but don't remove it
if ( videoDeviceFilter != null )
removeDownstream( videoDeviceFilter, (videoCompressor==null) );
if ( audioDeviceFilter != null )
removeDownstream( audioDeviceFilter, (audioCompressor==null) );
// These filters should have been removed by the
// calls above. (Is there anyway to check?)
muxFilter = null;
fileWriterFilter = null;
}
}
/// <summary>
/// Removes all filters downstream from a filter from the graph.
/// This is called only by derenderGraph() to remove everything
/// from the graph except the devices and compressors. The parameter
/// "removeFirstFilter" is used to keep a compressor (that should
/// be immediately downstream of the device) if one is begin used.
/// </summary>
protected void removeDownstream( IBaseFilter filter, bool removeFirstFilter )
{
// Get a pin enumerator off the filter
IEnumPins pinEnum;
int hr = filter.EnumPins( out pinEnum );
pinEnum.Reset();
if( (hr == 0) && (pinEnum != null) )
{
// Loop through each pin
IPin[] pins = new IPin[1];
int f;
do
{
// Get the next pin
hr = pinEnum.Next( 1, pins, out f );
if( (hr == 0) && (pins[0] != null) )
{
// Get the pin it is connected to
IPin pinTo = null;
pins[0].ConnectedTo( out pinTo );
if ( pinTo != null )
{
// Is this an input pin?
PinInfo info = new PinInfo();
hr = pinTo.QueryPinInfo( out info );
if( (hr == 0) && (info.dir == (PinDirection.Input)) )
{
// Recurse down this branch
removeDownstream( info.filter, true );
// Disconnect
graphBuilder.Disconnect( pinTo );
graphBuilder.Disconnect( pins[0] );
// Remove this filter
// but don't remove the video or audio compressors
if ( ( info.filter != videoCompressorFilter ) &&
( info.filter != audioCompressorFilter ) )
graphBuilder.RemoveFilter( info.filter );
}
Marshal.ReleaseComObject( info.filter );
Marshal.ReleaseComObject( pinTo );
}
Marshal.ReleaseComObject( pins[0] );
}
}
while( hr == 0 );
Marshal.ReleaseComObject( pinEnum ); pinEnum = null;
}
}
/// <summary>
/// Completely tear down a filter graph and
/// release all associated resources.
/// </summary>
protected void destroyGraph()
{
// Derender the graph (This will stop the graph
// and release preview window. It also destroys
// half of the graph which is unnecessary but
// harmless here.) (ignore errors)
try{ derenderGraph(); } catch {}
// Update the state after derender because it
// depends on correct status. But we also want to
// update the state as early as possible in case
// of error.
graphState = GraphState.Null;
isCaptureRendered = false;
isPreviewRendered = false;
// Remove graph from the ROT
if ( rotCookie != 0 )
{
DsROT.RemoveGraphFromRot( ref rotCookie );
rotCookie = 0;
}
// Remove filters from the graph
// This should be unnecessary but the Nvidia WDM
// video driver cannot be used by this application
// again unless we remove it. Ideally, we should
// simply enumerate all the filters in the graph
// and remove them. (ignore errors)
if ( muxFilter != null )
graphBuilder.RemoveFilter( muxFilter );
if ( videoCompressorFilter != null )
graphBuilder.RemoveFilter( videoCompressorFilter );
if ( audioCompressorFilter != null )
graphBuilder.RemoveFilter( audioCompressorFilter );
if ( videoDeviceFilter != null )
graphBuilder.RemoveFilter( videoDeviceFilter );
if ( audioDeviceFilter != null )
graphBuilder.RemoveFilter( audioDeviceFilter );
// Clean up properties
if ( videoSources != null )
videoSources.Dispose(); videoSources = null;
if ( audioSources != null )
audioSources.Dispose(); audioSources = null;
if ( propertyPages != null )
propertyPages.Dispose(); propertyPages = null;
if ( tuner != null )
tuner.Dispose(); tuner = null;
// Cleanup
if ( graphBuilder != null )
Marshal.ReleaseComObject( graphBuilder ); graphBuilder = null;
if ( captureGraphBuilder != null )
Marshal.ReleaseComObject( captureGraphBuilder ); captureGraphBuilder = null;
if ( muxFilter != null )
Marshal.ReleaseComObject( muxFilter ); muxFilter = null;
if ( fileWriterFilter != null )
Marshal.ReleaseComObject( fileWriterFilter ); fileWriterFilter = null;
if ( videoDeviceFilter != null )
Marshal.ReleaseComObject( videoDeviceFilter ); videoDeviceFilter = null;
if ( audioDeviceFilter != null )
Marshal.ReleaseComObject( audioDeviceFilter ); audioDeviceFilter = null;
if ( videoCompressorFilter != null )
Marshal.ReleaseComObject( videoCompressorFilter ); videoCompressorFilter = null;
if ( audioCompressorFilter != null )
Marshal.ReleaseComObject( audioCompressorFilter ); audioCompressorFilter = null;
// These are copies of graphBuilder
mediaControl = null;
videoWindow = null;
// For unmanaged objects we haven't released explicitly
GC.Collect();
}
/// <summary> Resize the preview when the PreviewWindow is resized </summary>
protected void onPreviewWindowResize(object sender, EventArgs e)
{
if ( videoWindow != null )
{
// Position video window in client rect of owner window
Rectangle rc = previewWindow.ClientRectangle;
videoWindow.SetWindowPosition( 0, 0, rc.Right, rc.Bottom );
}
}
/// <summary>
/// Get a valid temporary filename (with path). We aren't using
/// Path.GetTempFileName() because it creates a 0-byte file
/// </summary>
protected string getTempFilename()
{
string s;
try
{
int count = 0;
int i;
Random r = new Random();
string tempPath = Path.GetTempPath();
do
{
i = r.Next();
s = Path.Combine( tempPath, i.ToString("X") + ".avi" );
count++;
if ( count > 100 ) throw new InvalidOperationException( "Unable to find temporary file." );
} while ( File.Exists( s ) );
}
catch { s = "c:\temp.avi"; }
return( s );
}
/// <summary>
/// Retrieves the value of one member of the IAMStreamConfig format block.
/// Helper function for several properties that expose
/// video/audio settings from IAMStreamConfig.GetFormat().
/// IAMStreamConfig.GetFormat() returns a AMMediaType struct.
/// AMMediaType.formatPtr points to a format block structure.
/// This format block structure may be one of several
/// types, the type being determined by AMMediaType.formatType.
/// </summary>
protected object getStreamConfigSetting( IAMStreamConfig streamConfig, string fieldName)
{
if ( streamConfig == null )
throw new NotSupportedException();
assertStopped();
derenderGraph();
object returnValue = null;
IntPtr pmt = IntPtr.Zero;
AMMediaType mediaType = new AMMediaType();
try
{
// Get the current format info
int hr = streamConfig.GetFormat( out pmt );
if ( hr != 0 )
Marshal.ThrowExceptionForHR( hr );
Marshal.PtrToStructure( pmt, mediaType );
// The formatPtr member points to different structures
// dependingon the formatType
object formatStruct;
if ( mediaType.formatType == FormatType.WaveEx )
formatStruct = new WaveFormatEx();
else if ( mediaType.formatType == FormatType.VideoInfo )
formatStruct = new VideoInfoHeader();
else if ( mediaType.formatType == FormatType.VideoInfo2 )
formatStruct = new VideoInfoHeader2();
else
throw new NotSupportedException( "This device does not support a recognized format block." );
// Retrieve the nested structure
Marshal.PtrToStructure( mediaType.formatPtr, formatStruct );
// Find the required field
Type structType = formatStruct.GetType();
FieldInfo fieldInfo = structType.GetField( fieldName );
if ( fieldInfo == null )
throw new NotSupportedException( "Unable to find the member '" + fieldName + "' in the format block." );
// Extract the field's current value
returnValue = fieldInfo.GetValue( formatStruct );
}
finally
{
DsUtils.FreeAMMediaType( mediaType );
Marshal.FreeCoTaskMem( pmt );
}
renderGraph();
startPreviewIfNeeded();
return( returnValue );
}
/// <summary>
/// Set the value of one member of the IAMStreamConfig format block.
/// Helper function for several properties that expose
/// video/audio settings from IAMStreamConfig.GetFormat().
/// IAMStreamConfig.GetFormat() returns a AMMediaType struct.
/// AMMediaType.formatPtr points to a format block structure.
/// This format block structure may be one of several
/// types, the type being determined by AMMediaType.formatType.
/// </summary>
protected object setStreamConfigSetting( IAMStreamConfig streamConfig, string fieldName, object newValue)
{
if ( streamConfig == null )
throw new NotSupportedException();
assertStopped();
derenderGraph();
object returnValue = null;
IntPtr pmt = IntPtr.Zero;
AMMediaType mediaType = new AMMediaType();
try
{
// Get the current format info
int hr = streamConfig.GetFormat( out pmt );
if ( hr != 0 )
Marshal.ThrowExceptionForHR( hr );
Marshal.PtrToStructure( pmt, mediaType );
// The formatPtr member points to different structures
// dependingon the formatType
object formatStruct;
if ( mediaType.formatType == FormatType.WaveEx )
formatStruct = new WaveFormatEx();
else if ( mediaType.formatType == FormatType.VideoInfo )
formatStruct = new VideoInfoHeader();
else if ( mediaType.formatType == FormatType.VideoInfo2 )
formatStruct = new VideoInfoHeader2();
else
throw new NotSupportedException( "This device does not support a recognized format block." );
// Retrieve the nested structure
Marshal.PtrToStructure( mediaType.formatPtr, formatStruct );
// Find the required field
Type structType = formatStruct.GetType();
FieldInfo fieldInfo = structType.GetField( fieldName );
if ( fieldInfo == null )
throw new NotSupportedException( "Unable to find the member '" + fieldName + "' in the format block." );
// Update the value of the field
fieldInfo.SetValue( formatStruct, newValue );
// PtrToStructure copies the data so we need to copy it back
Marshal.StructureToPtr( formatStruct, mediaType.formatPtr, false );
// Save the changes
hr = streamConfig.SetFormat( mediaType );
if ( hr != 0 )
Marshal.ThrowExceptionForHR( hr );
}
finally
{
DsUtils.FreeAMMediaType( mediaType );
Marshal.FreeCoTaskMem( pmt );
}
renderGraph();
startPreviewIfNeeded();
return( returnValue );
}
/// <summary>
/// Assert that the class is in a Stopped state.
/// </summary>
protected void assertStopped()
{
if ( !Stopped )
throw new InvalidOperationException( "This operation not allowed while Capturing. Please Stop the current capture." );
}
}
}
Submit an article or tip