Create a Console App in Visual Studio on Windows¶

This topic describes the steps needed to configure a C++ Console App in Visual Studio. These steps have been verified to work with Visual Studio 2022 Community Edition, on Windows 11.

The code snippets used in this article are from the simple_converter Windows sample. This sample takes a WMV media file as input and converts it to H.265/HEVC video and AAC audio in MP4 container.

Create the Visual Studio project¶

Create a C++, Console App in Visual Studio. Name the project simple-converter. Check Place solution and project in the same directory.

Download the 64 bit version of AVBlocks for C++ (Windows). The file you need will have a name similar to avblocks-v3.4.0-demo.1-windows.zip - the version number may differ.

You can also download it with PowerShell from the Visual Studio solution directory:

$BaseUrl = "https://github.com/avblocks/avblocks-core/releases/download"
$Version = "v3.4.0-demo.1"

Invoke-WebRequest `
    -Uri "${BaseUrl}/${Version}/avblocks-${Version}-windows.zip" `
    -OutFile "avblocks-${Version}-windows.zip"

Extract the ZIP archive in a location of your choice, then copy the include and lib directories to the avblocks subdirectory of the Visual Studio solution directory. The Visual Studio solution is the directory that contains the simple-converter.sln solution file.

If you downloaded the archive to the Visual Studio solution directory with PowerShell, you can extract it directly into the avblocks subdirectory:
```
Expand-Archive `
    -Path "avblocks-${Version}-windows.zip" `
    -DestinationPath "./avblocks" -Force
```
You should end up with a directory structure similar to the following:
```
simple-converter
├───avblocks
│   ├───include
│   └───lib
├───simple-converter.cpp
├───simple-converter.sln
└───simple-converter.vcxproj
```

Replace the contents of simple-converter.cpp with this code:

#include <primo/avblocks/avb.h>
#include <primo/platform/reference++.h>
#include <primo/platform/ustring.h>

#include <windows.h>

// link with AVBlocks64.lib
#pragma comment(lib, "./avblocks/lib/x64/AVBlocks64.lib")

using namespace primo;
using namespace primo::codecs;
using namespace primo::avblocks;

int wmain(int argc, wchar_t* argv[])
{
    // needed for WMV
    CoInitializeEx(nullptr, COINITBASE_MULTITHREADED);

    Library::initialize();

    auto inputFile = primo::ustring(L"Wildlife.wmv");
    auto outputFile = primo::ustring(L"Wildlife_h265_aac.mp4");

    auto inputInfo = primo::make_ref(Library::createMediaInfo());
    inputInfo->inputs()->at(0)->setFile(inputFile);

    if (inputInfo->open()) {
        auto inputSocket = primo::make_ref(
            Library::createMediaSocket(inputInfo.get())
        );

        // Start with MP4 / H.264 + AAC preset, then change video to H.265
        auto outputSocket = primo::make_ref(
            Library::createMediaSocket(Preset::Video::Generic::MP4::Base_H264_AAC)
        );

        // Get the output video stream info and modify it for H.265/HEVC
        auto outVideoStream = static_cast<VideoStreamInfo*>(outputSocket
                                                            ->pins()->at(0)
                                                            ->streamInfo());
        outVideoStream->setStreamType(StreamType::H265);
        outVideoStream->setStreamSubType(StreamSubType::HEVC_Annex_B);

        // With H.265/HEVC we can use lower bitrate, e.g. 500 kbps
        outVideoStream->setBitrate(500'000);

        // Change the output file name
        outputSocket->setFile(outputFile);

        // Create Transcoder and configure it with
        // the input and output sockets
        auto transcoder = primo::make_ref(Library::createTranscoder());
        transcoder->inputs()->add(inputSocket.get());
        transcoder->outputs()->add(outputSocket.get());

        // Allow demo mode for the transcoder when
        // using the demo version of the library
        transcoder->setAllowDemoMode(true);

        // Run the transcoder
        if (transcoder->open()) {
            transcoder->run();
            transcoder->close();
        } else {
            std::wcerr << L"transcoder->open() failed: "
                       << primo::ustring(transcoder->error()->message())
                       << std::endl;
        }
    }

    Library::shutdown();

    CoUninitialize();

    return 0;
}

In Visual Studio, select Build | Configuration Manager from the menu, then select the x64 platform to the solution platforms.
In Visual Studio, select Project | simple-converter Properties from the menu, then C++ | General, then add ./avblocks/include to Additional Include Directories.
Build the project (Ctrl + Shift + B).
Copy the file AVBlocks64.dll from avblocks/lib/x64 to x64/Debug.

Run the application¶

Download the Wildlife.wmv sample file and save it in the Visual Studio solution directory (next to the simple-converter.sln solution file):
```
Invoke-WebRequest `
    -Uri https://archive.org/download/WildlifeSampleVideo/Wildlife.wmv `
    -OutFile Wildlife.wmv
```
Copy the file AVBlocks64.dll from avblocks/lib/x64 to x64/Debug.
Run the application in Visual Studio. Wait a few seconds for the Transcoder to finish. The converted file Wildlife_h265_aac.mp4 will be in the solution directory.

Troubleshooting¶

You may get The program can't start because AVBlocks64.dll is missing from your computer. Try reinstalling the program to fix this problem. or a similar message. To fix that, copy the file AVBlocks64.dll from avblocks/lib/x64 to x64/Debug.
transcoder->open() may fail if there is already a file Wildlife_h265_aac.mp4 in the project directory. Delete Wildlife_h265_aac.mp4 to solve that.