Leadtools.Multimedia Namespace > VideoFormat Class : Compression Property |
'Declaration Public ReadOnly Property Compression As Integer
'Usage Dim instance As VideoFormat Dim value As Integer value = instance.Compression
public int Compression {get;}
This property is the video compression type of the video format.
For compressed video and YUV formats, this member is a FOURCC code, specified as a DWORD value in little-endian order. For example, YUYV video has the FOURCC 'VYUY' or 0x56595559. For more information, see the Microsoft documentation on FOURCC Codes.
For uncompressed RGB formats, the following values are possible:
Value | Meaning |
---|---|
BI_RGB (0) | Uncompressed RGB. |
BI_BITFIELDS (3) | Uncompressed RGB with color masks. Valid for 16-bpp and 32-bpp bitmaps. |
For 16-bpp bitmaps, if biCompression equals BI_RGB, the format is always RGB 555. If biCompression equals BI_BITFIELDS, the format is either RGB 555 or RGB 565. Use the media subtype GUID to determine the specific RGB type.
Use the CaptureCtrl.VideoCaptureFormats property to access the VideoFormats object that contains all of the formats available for the current capture device. The VideoFormats indexer obtains a VideoFormat object for each of the supported video formats. The properties of each object, obtained using the VideoFormats indexer, are updated with information about that specific video format. This information includes the following information:Imports Leadtools Imports Leadtools.Multimedia Imports LeadtoolsMultimediaExamples.Fixtures Public _form As CaptureCtrlForm = New CaptureCtrlForm() Public _result As Boolean = False Public Sub VideoFormatExample() ' reference the capture control Dim capturectrl As CaptureCtrl = _form.CaptureCtrl Dim count As Integer, compression As Integer = 0, bits As Integer = 0, width As Integer = 0, height As Integer = 0 Dim found As Integer, selected As Integer = -1 ' set a video device, use the name of your device here If Not capturectrl.VideoDevices("USB") Is Nothing Then capturectrl.VideoDevices("USB").Selected = True End If ' reference the videoformats property Dim videoformats As VideoFormats = capturectrl.VideoCaptureFormats Try ' get count of available video formats count = videoformats.Count ' enumerate formats and select one For Each vf As VideoFormat In videoformats ' get the properties bits = vf.BitCount compression = vf.Compression width = vf.Width height = vf.Height ' select the format if it matches some criteria If bits = 16 AndAlso width = 640 AndAlso height = 480 Then vf.Selected = True Exit For End If Next vf ' reset the current item videoformats.Reset() ' get the currently selected format selected = videoformats.Selection ' find a format based on subtype name, width and height (YUY2 320 x 240 video) found = videoformats.IndexOf(Leadtools.Multimedia.Constants.MEDIASUBTYPE_YUY2, 320, 240) ' our found format is not selected, so select it If found <> selected Then videoformats.Selection = found End If ' get the new selected format selected = videoformats.Selection ' set our result based on what we expect _result = (count > 0 AndAlso selected = found) Catch e1 As Exception _result = False End Try End Sub
using Leadtools; using Leadtools.Multimedia; using LeadtoolsMultimediaExamples.Fixtures; public CaptureCtrlForm _form = new CaptureCtrlForm(); public bool _result = false; public void VideoFormatExample() { // reference the capture control CaptureCtrl capturectrl = _form.CaptureCtrl; int count, compression = 0, bits = 0, width = 0, height = 0; int found, selected = -1; // set a video device, use the name of your device here if (capturectrl.VideoDevices["USB"] != null) capturectrl.VideoDevices["USB"].Selected = true; // reference the videoformats property VideoFormats videoformats = capturectrl.VideoCaptureFormats; try { // get count of available video formats count = videoformats.Count; // enumerate formats and select one foreach (VideoFormat vf in videoformats) { // get the properties bits = vf.BitCount; compression = vf.Compression; width = vf.Width; height = vf.Height; // select the format if it matches some criteria if (bits == 16 && width == 640 && height == 480) { vf.Selected = true; break; } } // reset the current item videoformats.Reset(); // get the currently selected format selected = videoformats.Selection; // find a format based on subtype name, width and height (YUY2 320 x 240 video) found = videoformats.IndexOf(Constants.MEDIASUBTYPE_YUY2, 320, 240); // our found format is not selected, so select it if (found != selected) videoformats.Selection = found; // get the new selected format selected = videoformats.Selection; // set our result based on what we expect _result = (count > 0 && selected == found); } catch (Exception) { _result = false; } }