--- /dev/null
+$url = "https://raw.githubusercontent.com/opencv/opencv_3rdparty/@FFMPEG_BINARIES_COMMIT@/ffmpeg/opencv_ffmpeg_64.dll"
+$expected_md5 = "@FFMPEG_FILE_HASH_BIN64@"
+$output = "$PSScriptRoot\@OPENCV_BIN_INSTALL_PATH@\opencv_ffmpeg@OPENCV_DLLVERSION@_64.dll"
+
+Write-Output ("=" * 120)
+try {
+ Get-content -Path "$PSScriptRoot\etc\licenses\ffmpeg-readme.txt" -ErrorAction 'Stop'
+} catch {
+ Write-Output "Refer to OpenCV FFmpeg wrapper readme notes about library usage / licensing details."
+}
+Write-Output ("=" * 120)
+Write-Output ""
+
+if(![System.IO.File]::Exists($output)) {
+ try {
+ Write-Output ("Downloading: " + $output)
+ Import-Module BitsTransfer
+ $start_time = Get-Date
+ Start-BitsTransfer -Source $url -Destination $output -ErrorAction 'Stop'
+ Write-Output "Downloaded in $((Get-Date).Subtract($start_time).Seconds) seconds"
+ } catch {
+ $_ # Dump error
+ try {
+ Write-Output ("Downloading (second attempt): " + $output)
+ $start_time = Get-Date
+ Invoke-WebRequest -Uri $url -OutFile $output
+ Write-Output "Downloaded in $((Get-Date).Subtract($start_time).Seconds) seconds"
+ } catch {
+ Write-Output ("Can't download file: " + $output)
+ Write-Output ("URL: " + $url)
+ Write-Output "You need to download this file manually. Stop"
+ Pause
+ Exit
+ }
+ }
+} else {
+ Write-Output ("File exists: " + $output)
+ Write-Output ("Downloading is skipped. Remove this file and re-run this script to force downloading.")
+}
+
+if(![System.IO.File]::Exists($output)) {
+ Write-Output ("Destination file not found: " + $output)
+ Write-Output "Stop"
+ Pause
+ Exit
+}
+
+try {
+ $hash = Get-FileHash $output -Algorithm MD5 -ErrorAction 'Stop'
+
+ if($hash.Hash -eq $expected_md5) {
+ Write-Output "MD5 check passed"
+ } else {
+ Write-Output ("MD5 : " + $hash.Hash.toLower())
+ Write-Output ("Expected: " + $expected_md5)
+ Write-Output "MD5 hash mismatch"
+ }
+} catch {
+ $_ # Dump error
+ Write-Output "Can't check MD5 hash (requires PowerShell 4+)"
+}
+Pause
+Write-Output "Exit"