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'************************************************************************************* ' ' File name: MseqProcess.vb ' Location: See Matrox Example Launcher in the MIL Control Center ' ' ' Synopsis: This program shows the use of the MseqProcess() and MseqFeed() functions ' to perform real-time encoding of a sequence of captured images. ' ' The user's preprocessing and compression code is written in a hook ' function that will be called by MdigProcess() for each frame grabbed ' (see ProcessingFunction()). The queueing for encoding of the next ' frame is also made in that hook function to allow fully parallel ' execution of the capture and the encoding. ' ' Note: The average encoding time must be shorter than the grab time or ' some frames will be missed. Missed frames are very frequent when ' the encoding is done by software. Also, if the captured images ' are not displayed and the frame count is not drawn or printed ' in the hook function, the CPU usage is reduced significantly. ' ' When encoding a 1080p source it is recommended to have your ' MIL Non-Paged Memory set to at least 64MB. ' ' Copyright (C) Matrox Electronic Systems Ltd., 1992-2016. ' All Rights Reserved Imports Microsoft.VisualBasic Imports System Imports System.Runtime.InteropServices Imports System.Text Imports Matrox.MatroxImagingLibrary Namespace MseqProcess ' User's processing function hook data object. Friend Class ProcessingHookDataStruct Public MilDigitizer As MIL_ID Public MilImageDisp As MIL_ID Public MilSeqContext As MIL_ID Public ProcessedImageCount As MIL_INT Public ProcessingOperation As ProcessingHookOperation End Class ' Optional encoding end function hook data object. Friend Class EncodingFrameEndHookDataStruct Public EncodedImageCount As MIL_INT End Class ' Optional decoding end function hook data object. Friend Class DecodingFrameEndHookDataStruct Public DecodedImageCount As MIL_INT Public MilImageDisp As MIL_ID End Class Friend Enum ProcessingHookOperation DISPLAY ENCODE End Enum Friend Class Program ' Number of images in the buffering grab queue. ' Generally, increasing this number gives better real-time grab. Private Const BUFFERING_SIZE_MAX As Integer = 20 ' Target sequence file name and location. ' The temporary directory location can be reached with %temp% under Windows. Private Shared ReadOnly SEQUENCE_FILE As String = MIL.M_TEMP_DIR & "SeqProcess.mp4" ' Remote target sequence file name and location if Distributed MIL is used. Private Shared ReadOnly REMOTE_SEQUENCE_FILE As String = "remote:///" + SEQUENCE_FILE Shared Function Main(ByVal args() As String) As Integer Dim MilApplication As MIL_ID = MIL.M_NULL Dim MilRemoteApplication As MIL_ID = MIL.M_NULL Dim MilSystem As MIL_ID = MIL.M_NULL Dim MilDigitizer As MIL_ID = MIL.M_NULL Dim MilDisplay As MIL_ID = MIL.M_NULL Dim MilImageDisp As MIL_ID = MIL.M_NULL Dim MilGrabBufferList(BUFFERING_SIZE_MAX - 1) As MIL_ID Dim MilCompressContext As MIL_ID = MIL.M_NULL Dim MilDecompressContext As MIL_ID = MIL.M_NULL Dim LicenseModules As MIL_INT = 0 Dim MilSystemLocation As MIL_INT = MIL.M_NULL Dim MilGrabBufferListSize As MIL_INT Dim ProcessFrameCount As MIL_INT = 0 Dim NbFrames As MIL_INT = 0 Dim n As MIL_INT = 0 Dim EncodingDesiredFrameRate As Double = 0.0 Dim ProcessFrameRate As Double = 0.0 Dim SeqProcessFilePathSize As MIL_INT = 0 Dim SeqProcessFilePath As StringBuilder = Nothing Dim ProcessingUserHookData As New ProcessingHookDataStruct() Dim EncodingFrameEndUserHookData As New EncodingFrameEndHookDataStruct() Dim DecodingFrameEndUserHookData As New DecodingFrameEndHookDataStruct() Dim SeqSystemType As MIL_INT = MIL.M_NULL ' Allocate defaults. MIL.MappAllocDefault(MIL.M_DEFAULT, MilApplication, MilSystem, MilDisplay, MilDigitizer, MilImageDisp) MIL.MsysInquire(MilSystem, MIL.M_OWNER_APPLICATION, MilRemoteApplication) MilSystemLocation = MIL.MsysInquire(MilSystem, MIL.M_LOCATION, MIL.M_NULL) ' Check if the system is running under Windows. If (MIL.MappInquire(MilRemoteApplication, MIL.M_PLATFORM_OS_TYPE, MIL.M_NULL) <> MIL.M_OS_WINDOWS) Then If (MilSystemLocation = MIL.M_REMOTE) Then Console.WriteLine("The Distributed MIL server must run on a Windows system.") Else Console.WriteLine("This example only works with a Windows system.") End If Console.WriteLine("Press <Enter> to end.") Console.ReadKey() MIL.MappFreeDefault(MilApplication, MilSystem, MilDisplay, MilDigitizer, MilImageDisp) Return 0 End If ' Inquire MIL licenses. MIL.MappInquire(MilRemoteApplication, MIL.M_LICENSE_MODULES, LicenseModules) If ((LicenseModules And MIL.M_LICENSE_JPEGSTD) <> MIL.M_LICENSE_JPEGSTD) Then Console.WriteLine("Need a Compression/Decompression license to run this example.") Console.WriteLine("Press <Enter> to end.") Console.ReadKey() MIL.MappFreeDefault(MilApplication, MilSystem, MilDisplay, MilDigitizer, MilImageDisp) Return 0 End If ' Allocate the grab buffers and clear them. MIL.MappControl(MIL.M_DEFAULT, MIL.M_ERROR, MIL.M_PRINT_DISABLE) For MilGrabBufferListSize = 0 To BUFFERING_SIZE_MAX - 1 MIL.MbufAllocColor(MilSystem, _ MIL.MdigInquire(MilDigitizer, MIL.M_SIZE_BAND, MIL.M_NULL), _ MIL.MdigInquire(MilDigitizer, MIL.M_SIZE_X, MIL.M_NULL), _ MIL.MdigInquire(MilDigitizer, MIL.M_SIZE_Y, MIL.M_NULL), _ 8 + MIL.M_UNSIGNED, MIL.M_IMAGE + MIL.M_GRAB + MIL.M_PROC, _ MilGrabBufferList(CType(MilGrabBufferListSize, Integer))) If MilGrabBufferList(CType(MilGrabBufferListSize, Integer)) <> MIL.M_NULL Then MIL.MbufClear(MilGrabBufferList(CType(MilGrabBufferListSize, Integer)), &HFF) Else Exit For End If Next MilGrabBufferListSize MIL.MappControl(MIL.M_DEFAULT, MIL.M_ERROR, MIL.M_PRINT_ENABLE) ' Free buffers to leave space for possible temporary buffers. n = 0 Do While n < 2 AndAlso MilGrabBufferListSize > 0 MilGrabBufferListSize -= 1 MIL.MbufFree(MilGrabBufferList(CType(MilGrabBufferListSize, Integer))) n += 1 Loop If MilGrabBufferListSize = 0 Then Console.WriteLine("!!! No grab buffers have been allocated. Need to set more Non-Paged Memory. !!!") MIL.MappFreeDefault(MilApplication, MilSystem, MilDisplay, MilDigitizer, MilImageDisp) Console.WriteLine("Press <Enter> to end.") Console.ReadKey() Return 1 End If ' Initialize the User's processing function data structure only for Display. ProcessingUserHookData.MilDigitizer = MilDigitizer ProcessingUserHookData.MilSeqContext = MIL.M_NULL ProcessingUserHookData.MilImageDisp = MilImageDisp ProcessingUserHookData.ProcessedImageCount = 0 ProcessingUserHookData.ProcessingOperation = ProcessingHookOperation.DISPLAY ' get a handle to the HookDataStruct object in the managed heap, we will use this ' handle to get the object back in the callback function Dim hUserData As GCHandle = GCHandle.Alloc(ProcessingUserHookData) ' Start the sequence acquisition. The preprocessing and encoding hook function ' is called for every frame grabbed. Dim ProcessingFunctionDelegate As MIL_DIG_HOOK_FUNCTION_PTR = AddressOf ProcessingFunction ' Start MdigProcess() to show the live camera output. MIL.MdigProcess(MilDigitizer, MilGrabBufferList, MilGrabBufferListSize, MIL.M_START, MIL.M_DEFAULT, ProcessingFunctionDelegate, GCHandle.ToIntPtr(hUserData)) ' Print a message. Console.Write(vbNewLine + "H.264 IMAGE SEQUENCE COMPRESSION." + vbNewLine) Console.Write("---------------------------------" + vbNewLine + vbNewLine) Console.Write("Press <Enter> to start compression." + vbCr) Console.ReadKey() ' Stop MdigProcess() MIL.MdigProcess(MilDigitizer, MilGrabBufferList, MilGrabBufferListSize, MIL.M_STOP, MIL.M_DEFAULT, ProcessingFunctionDelegate, GCHandle.ToIntPtr(hUserData)) ' Inquire the rate at which the frames were grabbed using MdigProcess() MIL.MdigInquire(MilDigitizer, MIL.M_PROCESS_FRAME_RATE, EncodingDesiredFrameRate) Console.Write("Grabbing frames at {0:0.00} frames/sec." + vbNewLine, EncodingDesiredFrameRate) ' Creates a context for the H.264 compression engine. Compression will be done ' using hardware or software depending on the system hardware configuration. MIL.MseqAlloc(MilSystem, MIL.M_DEFAULT, MIL.M_SEQ_COMPRESS, MIL.M_DEFAULT, MIL.M_DEFAULT, MilCompressContext) ' Specify the destination of the compressed file and the target container type. ' The last argument specifies to generate an MP4 file. MIL.MseqDefine(MilCompressContext, MIL.M_SEQ_OUTPUT(0) + MIL.M_SEQ_DEST(0), MIL.M_FILE, (If(MilSystemLocation <> MIL.M_REMOTE, SEQUENCE_FILE, REMOTE_SEQUENCE_FILE)), MIL.M_FILE_FORMAT_MP4) ' Set the compression context's settings. ' Sets the compression context's settings to compress frames at any resolution under ' 1920 x 1080. Any resolution higher than that will generate a warning that can be disabled ' using MseqControl with M_SETTING_AUTO_ADJUSTMENT. See documentation for more details. ' MIL.MseqControl(MilCompressContext, MIL.M_CONTEXT, MIL.M_STREAM_BIT_RATE_MODE, MIL.M_VARIABLE) ' MIL.M_VARIABLE or MIL.M_CONSTANT MIL.MseqControl(MilCompressContext, MIL.M_CONTEXT, MIL.M_STREAM_BIT_RATE, 5000) ' 5 Mbps bit rate MIL.MseqControl(MilCompressContext, MIL.M_CONTEXT, MIL.M_STREAM_BIT_RATE_MAX, 5000) ' 5 Mbps bit rate If EncodingDesiredFrameRate <> 0 Then MIL.MseqControl(MilCompressContext, MIL.M_CONTEXT, MIL.M_STREAM_FRAME_RATE, EncodingDesiredFrameRate) ' 60Hz frame rate. End If MIL.MseqControl(MilCompressContext, MIL.M_CONTEXT, MIL.M_STREAM_FRAME_RATE_MODE, MIL.M_VARIABLE) ' Attempts to update the file header with the encoding frame rate if lower than the specified frame rate. MIL.MseqControl(MilCompressContext, MIL.M_CONTEXT, MIL.M_STREAM_QUALITY, 100) ' 1=best speed, 100=best quality MIL.MseqControl(MilCompressContext, MIL.M_CONTEXT, MIL.M_STREAM_PROFILE, MIL.M_PROFILE_HIGH) ' MIL.M_PROFILE_BASELINE, MIL.M_PROFILE_MAIN, MIL.M_PROFILE_HIGH MIL.MseqControl(MilCompressContext, MIL.M_CONTEXT, MIL.M_STREAM_LEVEL, MIL.M_LEVEL_4_2) ' MIL.M_LEVEL_1, MIL.M_LEVEL_1B, MIL.M_LEVEL_1_1, MIL.M_LEVEL_1_2, MIL.M_LEVEL_1_3, ' MIL.M_LEVEL_2, MIL.M_LEVEL_2_1, MIL.M_LEVEL_2_2, ' MIL.M_LEVEL_3, MIL.M_LEVEL_3_1, MIL.M_LEVEL_3_2, ' MIL.M_LEVEL_4, MIL.M_LEVEL_4_1, MIL.M_LEVEL_4_2, ' MIL.M_LEVEL_5, MIL.M_LEVEL_5_1 MIL.MseqControl(MilCompressContext, MIL.M_CONTEXT, MIL.M_STREAM_GROUP_OF_PICTURE_SIZE, 30) ' Interval between I-Frame ' Initialize the optional encoding end function data structure. EncodingFrameEndUserHookData.EncodedImageCount = 0 ' get a handle to the HookDataStruct object in the managed heap, we will use this ' handle to get the object back in the callback function Dim EncodingFrameEndUserHookDataHandle As GCHandle = GCHandle.Alloc(EncodingFrameEndUserHookData) ' Register the encoding end function to the sequence context. Dim FrameEncodingEndFunctionDelegate As MIL_SEQ_HOOK_FUNCTION_PTR = AddressOf FrameEncodingEndFunction MIL.MseqHookFunction(MilCompressContext, MIL.M_FRAME_END, FrameEncodingEndFunctionDelegate, GCHandle.ToIntPtr(EncodingFrameEndUserHookDataHandle)) ' Provide a sample image to initialize the encoding engine accordingly. MIL.MseqControl(MilCompressContext, MIL.M_CONTEXT, MIL.M_BUFFER_SAMPLE, MilGrabBufferList(0)) ' Disable error prints because MseqProcess() might not support the current input source. MIL.MappControl(MIL.M_ERROR, MIL.M_PRINT_DISABLE) ' Start the encoding process, waits for buffer to be fed for encoding. MIL.MseqProcess(MilCompressContext, MIL.M_START, MIL.M_ASYNCHRONOUS) ' Checks if an error has been logged by MseqProcess(). If so, stop the example. If (CheckMseqProcessError(MilApplication, MilCompressContext)) Then ' An error happened during MseqProcess() and we need to free the allocated resources. MIL.MseqProcess(MilCompressContext, MIL.M_STOP, MIL.M_NULL) Dim SourceSizeX As MIL_INT = 0 Dim SourceSizeY As MIL_INT = 0 Dim SourceFPS As Double = 0.0 MIL.MdigInquire(MilDigitizer, MIL.M_SIZE_X, SourceSizeX) MIL.MdigInquire(MilDigitizer, MIL.M_SIZE_Y, SourceSizeY) MIL.MdigInquire(MilDigitizer, MIL.M_PROCESS_FRAME_RATE, SourceFPS) Console.WriteLine("Unable to perform H.264 encoding with the current input source of") Console.WriteLine("{0} X {1} @ {2:0.00} fps.", SourceSizeX, SourceSizeY, SourceFPS) Console.WriteLine(vbNewLine + "Example parameters are optimized for sources of") Console.WriteLine("1920 x 1080 @ 60 fps.") Console.WriteLine(vbNewLine + "You can try changing encoding parameters to better match your source." + vbNewLine) Console.WriteLine("Press <Enter> to end.") Console.ReadKey() Do While MilGrabBufferListSize > 0 MilGrabBufferListSize -= 1 MIL.MbufFree(MilGrabBufferList(CType(MilGrabBufferListSize, Integer))) MilGrabBufferList(CType(MilGrabBufferListSize, Integer)) = MIL.M_NULL Loop MIL.MseqFree(MilCompressContext) MIL.MappFreeDefault(MilApplication, MilSystem, MilDisplay, MilDigitizer, MilImageDisp) Return 0 End If ' MseqProcess() is running without error, so re-enable the error print. MIL.MappControl(MIL.M_ERROR, MIL.M_PRINT_ENABLE) ' Display the type of compression used. Console.Write("Live image capture and compression to file using ") MIL.MseqInquire(MilCompressContext, MIL.M_CONTEXT, MIL.M_CODEC_TYPE, SeqSystemType) If SeqSystemType = MIL.M_HARDWARE + MIL.M_QSV Then Console.WriteLine("Hardware acceleration.") Else ' MIL.M_SOFTWARE + MIL.M_QSV Console.WriteLine("Software implementation.") End If ' Set the sequence context id in the user hook data structure to start ' feeding buffers for encoding in ProcessingFunction. ' ProcessingUserHookData.MilSeqContext = MilCompressContext ProcessingUserHookData.ProcessedImageCount = 0 ProcessingUserHookData.ProcessingOperation = ProcessingHookOperation.ENCODE MIL.MdigProcess(MilDigitizer, MilGrabBufferList, MilGrabBufferListSize, MIL.M_START, MIL.M_DEFAULT, ProcessingFunctionDelegate, GCHandle.ToIntPtr(hUserData)) ' NOTE: Now the main() is free to perform other tasks while the compression is executing. ' --------------------------------------------------------------------------------------- ' Print a message and wait for a key press after a minimum number of frames. Console.WriteLine("Press <Enter> to stop." + vbNewLine) Console.ReadKey() ' Stop the processing. MIL.MdigProcess(MilDigitizer, MilGrabBufferList, MilGrabBufferListSize, MIL.M_STOP + MIL.M_WAIT, MIL.M_DEFAULT, ProcessingFunctionDelegate, GCHandle.ToIntPtr(hUserData)) ' Free the processing user data handle. hUserData.Free() ' Stop the encoding process MIL.MseqProcess(MilCompressContext, MIL.M_STOP, MIL.M_WAIT) ' Make sure the hook handler function delegate is not prematurely garbage collected since ' only MIL has a reference to it. GC.KeepAlive(FrameEncodingEndFunctionDelegate) ' Free the encoding user data handle. EncodingFrameEndUserHookDataHandle.Free() ' Print statistics. MIL.MdigInquire(MilDigitizer, MIL.M_PROCESS_FRAME_COUNT, ProcessFrameCount) MIL.MdigInquire(MilDigitizer, MIL.M_PROCESS_FRAME_RATE, ProcessFrameRate) Console.WriteLine("{0} frames encoded at {1:0.00} frames/sec ({2:0.0} ms/frame).", ProcessFrameCount, ProcessFrameRate, 1000.0 / ProcessFrameRate) Console.WriteLine() MIL.MseqInquire(MilCompressContext, MIL.M_SEQ_OUTPUT(0) + MIL.M_SEQ_DEST(0), MIL.M_STREAM_FILE_NAME_SIZE, SeqProcessFilePathSize) SeqProcessFilePath = New StringBuilder(CInt(Fix(SeqProcessFilePathSize))) MIL.MseqInquire(MilCompressContext, MIL.M_SEQ_OUTPUT(0) + MIL.M_SEQ_DEST(0), MIL.M_STREAM_FILE_NAME, SeqProcessFilePath) Console.WriteLine("The video sequence file was written to:") Console.WriteLine("{0}.", SeqProcessFilePath.ToString()) Console.WriteLine() Console.WriteLine("It can be played back using any compatible video player.") ' Free the grab buffers and sequence context. Do While MilGrabBufferListSize > 0 MilGrabBufferListSize -= 1 MIL.MbufFree(MilGrabBufferList(CType(MilGrabBufferListSize, Integer))) MilGrabBufferList(CType(MilGrabBufferListSize, Integer)) = MIL.M_NULL Loop MIL.MseqFree(MilCompressContext) ' Wait for a key to start the replay. Console.WriteLine("Press <Enter> to replay encoded sequence.") Console.ReadKey() MIL.MseqAlloc(MilSystem, MIL.M_DEFAULT, MIL.M_SEQ_DECOMPRESS, MIL.M_DEFAULT, MIL.M_DEFAULT, MilDecompressContext) ' Specify the destination of the compressed file and the target container type. ' The last argument specifies to generate an MP4 file. MIL.MseqDefine(MilDecompressContext, MIL.M_SEQ_INPUT(0), MIL.M_FILE, (If(MilSystemLocation <> MIL.M_REMOTE, SEQUENCE_FILE, REMOTE_SEQUENCE_FILE)), MIL.M_FILE_FORMAT_MP4) Dim outputFrameRate As Double = 0.0 MIL.MseqInquire(MilDecompressContext, MIL.M_SEQ_INPUT(0), MIL.M_STREAM_FRAME_RATE, outputFrameRate) Console.WriteLine() Console.WriteLine("Replaying file at {0:0.00} frames/second.", outputFrameRate) ' Initialize the optional decoding end function data structure. DecodingFrameEndUserHookData.DecodedImageCount = 0 DecodingFrameEndUserHookData.MilImageDisp = MilImageDisp ' get a handle to the HookDataStruct object in the managed heap, we will use this ' handle to get the object back in the callback function Dim DecodingFrameEndUserHookDataHandle As GCHandle = GCHandle.Alloc(DecodingFrameEndUserHookData) ' Register the decoding end function to the sequence context. Dim FrameDecodingEndFunctionDelegate As MIL_SEQ_HOOK_FUNCTION_PTR = AddressOf FrameDecodingEndFunction MIL.MseqHookFunction(MilDecompressContext, MIL.M_FRAME_END, FrameDecodingEndFunctionDelegate, GCHandle.ToIntPtr(DecodingFrameEndUserHookDataHandle)) ' Start the decoding process, waits for buffer to be fed for encoding. MIL.MseqProcess(MilDecompressContext, MIL.M_START, MIL.M_ASYNCHRONOUS) ' Print a message and wait for a key press after a minimum number of frames. Console.WriteLine("Press <Enter> to stop." + vbNewLine) Console.ReadKey() ' Stop the play back. MIL.MseqProcess(MilDecompressContext, MIL.M_STOP, MIL.M_NULL) ' Make sure the hook handler function delegate is not prematurely garbage collected since ' only MIL has a reference to it. GC.KeepAlive(FrameDecodingEndFunctionDelegate) ' Free the decoding user data handle. DecodingFrameEndUserHookDataHandle.Free() MIL.MseqFree(MilDecompressContext) ' Wait for a key to end. Console.WriteLine("Press <Enter> to end.") Console.ReadKey() ' Release defaults. MIL.MappFreeDefault(MilApplication, MilSystem, MilDisplay, MilDigitizer, MilImageDisp) Return 0 End Function ' Local defines. Private Const STRING_LENGTH_MAX As Integer = 20 Private Const STRING_POS_X As Integer = 20 Private Const STRING_POS_Y As Integer = 20 ' User's processing function called every time a grab buffer is modified. ' ------------------------------------------------------------------------ Private Shared Function ProcessingFunction(ByVal HookType As MIL_INT, ByVal HookId As MIL_ID, ByVal HookDataPtr As IntPtr) As MIL_INT ' this is how to check if the user data is null, the IntPtr class ' contains a member, Zero, which exists solely for this purpose If (Not IntPtr.Zero.Equals(HookDataPtr)) Then ' get the handle to the ProcessingHookDataStruct object back from the IntPtr Dim hUserData As GCHandle = GCHandle.FromIntPtr(HookDataPtr) ' get a reference to the ProcessingHookDataStruct object Dim UserHookDataPtr As ProcessingHookDataStruct = TryCast(hUserData.Target, ProcessingHookDataStruct) Dim ModifiedBufferId As MIL_ID = MIL.M_NULL Dim Text As String ' Retrieve the MIL_ID of the grabbed buffer. MIL.MdigGetHookInfo(HookId, MIL.M_MODIFIED_BUFFER + MIL.M_BUFFER_ID, ModifiedBufferId) Select Case UserHookDataPtr.ProcessingOperation Case ProcessingHookOperation.DISPLAY ' Update the display with the last captured image. MIL.MbufCopy(ModifiedBufferId, UserHookDataPtr.MilImageDisp) Case ProcessingHookOperation.ENCODE ' Increase the compressed images count. UserHookDataPtr.ProcessedImageCount += 1 ' Print and draw the frame count (comment this block to reduce CPU usage). Console.Write("Processing frame #{0}." & Constants.vbCr, UserHookDataPtr.ProcessedImageCount) Text = String.Format("{0}", UserHookDataPtr.ProcessedImageCount) MIL.MgraText(MIL.M_DEFAULT, ModifiedBufferId, STRING_POS_X, STRING_POS_Y, Text) ' Enqueue the grabbed buffer for parallel encoding. MIL.MseqFeed(UserHookDataPtr.MilSeqContext, ModifiedBufferId, MIL.M_DEFAULT) ' Update the display with the last captured image. MIL.MbufCopy(ModifiedBufferId, UserHookDataPtr.MilImageDisp) End Select End If Return 0 End Function ' Optional encoding end function called every time a buffer is finished being compressed. ' ---------------------------------------------------------------------------------------- Private Shared Function FrameEncodingEndFunction(ByVal HookType As MIL_INT, ByVal HookId As MIL_ID, ByVal HookDataPtr As IntPtr) As MIL_INT ' this is how to check if the user data is null, the IntPtr class ' contains a member, Zero, which exists solely for this purpose If (Not IntPtr.Zero.Equals(HookDataPtr)) Then ' get the handle to the FrameEndHookDataStruct object back from the IntPtr Dim hUserData As GCHandle = GCHandle.FromIntPtr(HookDataPtr) ' get a reference to the EncodingFrameEndHookDataStruct object Dim UserHookDataPtr As EncodingFrameEndHookDataStruct = TryCast(hUserData.Target, EncodingFrameEndHookDataStruct) ' Frame end hook post processing. If HookType = MIL.M_FRAME_END Then Dim CompressedBufferId As MIL_ID = MIL.M_NULL Dim CompressedDataPtr As MIL_INT = MIL.M_NULL Dim CompressedDataSize As MIL_INT = 0 ' Increment a encoded frame counter UserHookDataPtr.EncodedImageCount += 1 ' Retrieve the MIL_ID of the encoded buffer. MIL.MseqGetHookInfo(HookId, MIL.M_MODIFIED_BUFFER + MIL.M_BUFFER_ID, CompressedBufferId) ' Retrieves the address of the encoded data. MIL.MbufInquire(CompressedBufferId, MIL.M_HOST_ADDRESS, CompressedDataPtr) ' Retrieves the size in bytes of the encoded data. MIL.MbufInquire(CompressedBufferId, MIL.M_SIZE_BYTE, CompressedDataSize) ' ----------------------------------------------------------------------------------------------- ' Here you can do any action with the encoded data, such as send the buffer through a network ' stream. If the processing done on the compressed data is long, it is recommended to copy the ' buffer and to process it in a separate thread to avoid blocking the compression's flow. ' ----------------------------------------------------------------------------------------------- End If End If Return 0 End Function ' Optional encoding end function called every time a buffer is finished being compressed. ' ---------------------------------------------------------------------------------------- Private Shared Function FrameDecodingEndFunction(ByVal HookType As MIL_INT, ByVal HookId As MIL_ID, ByVal HookDataPtr As IntPtr) As MIL_INT ' this is how to check if the user data is null, the IntPtr class ' contains a member, Zero, which exists solely for this purpose If (Not IntPtr.Zero.Equals(HookDataPtr)) Then ' get the handle to the FrameEndHookDataStruct object back from the IntPtr Dim hUserData As GCHandle = GCHandle.FromIntPtr(HookDataPtr) ' get a reference to the DecodingFrameEndHookDataStruct object Dim UserHookDataPtr As DecodingFrameEndHookDataStruct = TryCast(hUserData.Target, DecodingFrameEndHookDataStruct) ' Frame end hook post processing. If HookType = MIL.M_FRAME_END Then Dim DecompressedBufferId As MIL_ID = MIL.M_NULL ' Increment a encoded frame counter UserHookDataPtr.DecodedImageCount += 1 ' Retrieve the MIL_ID of the encoded buffer. MIL.MseqGetHookInfo(HookId, MIL.M_MODIFIED_BUFFER + MIL.M_BUFFER_ID, DecompressedBufferId) ' ----------------------------------------------------------------------------------------------- ' Here you can do any action with the decoded buffer. ' ----------------------------------------------------------------------------------------------- MIL.MbufCopy(DecompressedBufferId, UserHookDataPtr.MilImageDisp) End If End If Return 0 End Function Private Structure MSEQ_PARAM Public Sub New(ByVal controlName As String, ByVal controlType As MIL_INT, ByVal originalValue As MIL_INT, ByVal effectiveValue As MIL_INT) Me.ControlName = controlName Me.ControlType = controlType Me.OriginalValue = originalValue Me.EffectiveValue = effectiveValue End Sub Public ControlName As String Public ControlType As MIL_INT Public OriginalValue As MIL_INT Public EffectiveValue As MIL_INT End Structure ' Checks if MseqProcess generated an error or a warning. ' This function prints out the MIL error message, if any. ' If a sequence context parameter has been modified, it means that only a warning has been generated. ' If it is a warning, it displays the control that has been modified. ' If it is an error, it return M_YES to indicate that the example needs to be stopped. ' ---------------------------------------------------------------------------------------------------- Private Shared Function CheckMseqProcessError(ByVal MilApplication As MIL_ID, ByVal MilCompressContext As MIL_ID) As Boolean Dim IsError As Boolean = False Dim IsWarning As Boolean = False Dim MilErrorCode As MIL_INT = PrintMilErrorMessage(MilApplication) ' MseqProcess generated an error, check in details if it is a warning or an error. If MilErrorCode <> MIL.M_NULL_ERROR Then Dim MseqParamList() As MSEQ_PARAM = {New MSEQ_PARAM("M_STREAM_BIT_RATE_MODE", MIL.M_STREAM_BIT_RATE_MODE, 0, 0), _ New MSEQ_PARAM("M_STREAM_BIT_RATE", MIL.M_STREAM_BIT_RATE, 0, 0), _ New MSEQ_PARAM("M_STREAM_BIT_RATE_MAX", MIL.M_STREAM_BIT_RATE_MAX, 0, 0), _ New MSEQ_PARAM("M_STREAM_FRAME_RATE_MODE", MIL.M_STREAM_FRAME_RATE_MODE, 0, 0), _ New MSEQ_PARAM("M_STREAM_QUALITY", MIL.M_STREAM_QUALITY, 0, 0), _ New MSEQ_PARAM("M_STREAM_PROFILE", MIL.M_STREAM_PROFILE, 0, 0), _ New MSEQ_PARAM("M_STREAM_LEVEL", MIL.M_STREAM_LEVEL, 0, 0), _ New MSEQ_PARAM("M_STREAM_GROUP_OF_PICTURE_SIZE", MIL.M_STREAM_GROUP_OF_PICTURE_SIZE, 0, 0)} Dim NumberOfModifiedParams As MIL_INT = 0 ' Loop though the param list to find which one has been internally modified. For ParamIndex As Integer = 0 To MseqParamList.Length - 1 ' Query the original control values. MIL.MseqInquire(MilCompressContext, MIL.M_CONTEXT, MseqParamList(ParamIndex).ControlType, MseqParamList(ParamIndex).OriginalValue) ' Query the effective control values. MIL.MseqInquire(MilCompressContext, MIL.M_CONTEXT, MseqParamList(ParamIndex).ControlType Or MIL.M_EFFECTIVE_VALUE, MseqParamList(ParamIndex).EffectiveValue) ' If the original value is different than the effective value, ' the error received is only a warning and processing can continue. ' If MseqParamList(ParamIndex).OriginalValue <> MseqParamList(ParamIndex).EffectiveValue Then If NumberOfModifiedParams = 0 Then Console.Write(Constants.vbLf & "Parameter(s) that have been internally modified:" & Constants.vbLf) End If ' Prints the Control type internally modified. Console.WriteLine("- {0}", MseqParamList(ParamIndex).ControlName) NumberOfModifiedParams += 1 IsWarning = True End If Next ParamIndex Console.WriteLine() ' If the error logged is not a warning, you cannot encode the current input source. ' The example needs to be stopped. ' If (Not IsWarning) Then IsError = True End If End If Return IsError End Function ' Print the current error code in the console Private Shared Function PrintMilErrorMessage(ByVal MilApplication As MIL_ID) As MIL_INT Dim MilErrorCode As MIL_INT Dim MilErrorMsg As New StringBuilder(MIL.M_ERROR_MESSAGE_SIZE) Dim MilErrorSubCode(2) As MIL_INT Dim MilErrorSubMsg(2) As StringBuilder ' Initialize MilErrorSubMsg array. For i As Integer = 0 To 2 MilErrorSubMsg(i) = New StringBuilder(MIL.M_ERROR_MESSAGE_SIZE) Next i MilErrorCode = MIL.MappGetError(MilApplication, MIL.M_CURRENT + MIL.M_MESSAGE, MilErrorMsg) If MilErrorCode <> MIL.M_NULL_ERROR Then ' Collects Mil error messages and sub-messages Dim subCount As MIL_INT = 3 MIL.MappGetError(MilApplication, MIL.M_CURRENT_SUB_NB, subCount) MilErrorSubCode(0) = MIL.MappGetError(MilApplication, MIL.M_CURRENT_SUB_1 + MIL.M_MESSAGE, MilErrorSubMsg(0)) MilErrorSubCode(1) = MIL.MappGetError(MilApplication, MIL.M_CURRENT_SUB_2 + MIL.M_MESSAGE, MilErrorSubMsg(1)) MilErrorSubCode(2) = MIL.MappGetError(MilApplication, MIL.M_CURRENT_SUB_3 + MIL.M_MESSAGE, MilErrorSubMsg(2)) Console.WriteLine(Constants.vbLf & "MseqProcess generated a warning or an error:") Console.WriteLine(" {0}", MilErrorMsg.ToString()) For i As Integer = 0 To CType(subCount - 1, Integer) If MilErrorSubCode(i) <> 0 Then Console.WriteLine(" {0}", MilErrorSubMsg(i)) End If Next i End If Return MilErrorCode End Function End Class End Namespace