# Video Capture to Windows Media Video (WMV) Using External Profiles

# Introduction

Capturing video to Windows Media Video (WMV) format is a common requirement in many software applications. This guide provides a detailed walkthrough of implementing video capture functionality using external WMV profiles in Delphi, C++ MFC, and VB6 applications. The WMV format remains popular due to its compatibility with Windows platforms and efficient compression algorithms that balance quality and file size.

# Understanding WMV and External Profiles

Windows Media Video (WMV) is a compressed video file format developed by Microsoft as part of the Windows Media framework. When capturing video to WMV format, using external profiles allows for greater flexibility and customization of the output. External profiles contain pre-configured settings that define:

  • Video resolution
  • Bitrate
  • Frame rate
  • Compression quality
  • Audio settings
  • Other encoding parameters

By leveraging external profiles, developers can quickly implement different quality presets without having to manually configure each parameter in code.

# Implementation Steps

# Step 1: Setting Up Your Environment

Before implementing video capture functionality, ensure your development environment is properly configured:

  1. Install the necessary video capture component
  2. Add the component reference to your project
  3. Design your user interface to include:
    • A file selector for choosing the WMV profile
    • Output file location selector
    • Video capture preview window
    • Start/Stop capture controls

# Step 2: Selecting a WMV Profile

The first step in the implementation is to specify which WMV profile to use for encoding. This profile contains all the encoding parameters that will be applied to the captured video.

# Delphi 

VideoCapture1.WMV_Profile_Filename := "output.wmv";

# C++ MFC 

m_videoCapture.SetWMVProfileFilename(_T("output.wmv"));

# VB6 

VideoCapture1.WMV_Profile_Filename = "output.wmv"

# Step 3: Configuring the Output Format

Once the profile is selected, you need to configure the component to use WMV as the output format. This tells the capture component which encoder to use for processing the video stream.

# Delphi 

VideoCapture1.OutputFormat := Format_WMV;

# C++ MFC 

m_videoCapture.SetOutputFormat(FORMAT_WMV);

# VB6 

VideoCapture1.OutputFormat = FORMAT_WMV

# Step 4: Setting the Capture Mode

The capture component can operate in various modes, so it's important to explicitly set it to video capture mode.

# Delphi 

VideoCapture1.Mode := Mode_Video_Capture;

# C++ MFC 

m_videoCapture.SetMode(MODE_VIDEO_CAPTURE);

# VB6 

VideoCapture1.Mode = MODE_VIDEO_CAPTURE

This ensures that the component is configured for continuous video recording rather than other modes like snapshot capture or streaming.

# Step 5: Starting the Video Capture

With all the configuration in place, the final step is to start the actual capture process.

# Delphi 

VideoCapture1.Start;

# C++ MFC 

m_videoCapture.Start();

# VB6 

VideoCapture1.Start

This command begins the capture process using all the previously configured settings.

# Advanced Configuration Options

# Custom Output File Naming

You can implement custom file naming for your captured video files:

# Delphi 

VideoCapture1.Output_Filename := 'C:\Captures\Video_' + FormatDateTime('yyyymmdd_hhnnss', Now) + '.wmv';

# C++ MFC 

CTime currentTime = CTime::GetCurrentTime();
CString fileName;
fileName.Format(_T("C:\\Captures\\Video_%04d%02d%02d_%02d%02d%02d.wmv"), 
                currentTime.GetYear(), currentTime.GetMonth(), currentTime.GetDay(),
                currentTime.GetHour(), currentTime.GetMinute(), currentTime.GetSecond());
m_videoCapture.SetOutputFilename(fileName);

# VB6 

VideoCapture1.Output_Filename = "C:\Captures\Video_" & Format(Now, "yyyymmdd_hhnnss") & ".wmv"

These examples create a timestamped filename to ensure each captured file has a unique name.

When designing your application, consider these best practices:

  1. Always verify device availability before attempting capture
  2. Provide feedback during long encoding operations
  3. Include a preview window so users can see what's being captured
  4. Implement a file size monitor for long recordings
  5. Test with various WMV profiles to ensure compatibility

# Conclusion

Implementing video capture to WMV format using external profiles provides flexibility and control over the capture process. The approach outlined in this guide works effectively in Delphi, C++ MFC, and VB6 development environments, allowing you to integrate professional-grade video capture capabilities into your applications.

By using external profiles, you can quickly switch between different quality settings without changing your code, which is ideal for applications that need to adapt to different use cases or hardware capabilities.

For additional code samples, visit our GitHub repository. If you need technical assistance with implementation, our support team is available to help.