Convert all images to jpg

Question

I need to convert all images in folder and subfolders to jpg. I need to batch this process with command file. GUI tools needles for me I need the script.

I tried to use mogrify.exe from ImageMagick, there is also convert.exe function, but afaik both of them are able to convert images.

I wrote next script:

$rootdir = "E:\Apps\скрипты\temp1\graphics"
$files = dir -r -i *.png $rootdir
foreach ($file in $files) {.\mogrify.exe -format png *jpg $file}

But it is not work, when I try to run it, I got errors:

mogrify.exe: unable to open file `*jpg' @ error/png.c/ReadPNGImage/3633.
mogrify.exe: Improper image header `E:\Apps\скрипты\temp1\graphics\telluric\day\
Athens\2011-07-03-17.png' @ error/png.c/ReadPNGImage/3641.
mogrify.exe: unable to open image `*jpg': Invalid argument @ error/blob.c/OpenBl
ob/2588.

Also I have find next code:

[Reflection.Assembly]::LoadWithPartialName('System.Drawing')

$img=[Drawing.Image]::FromFile("$(cd)\Max.jpg")
$img.Save("$(cd)\max.gif", 'Gif')
$img.Dispose()

How I can get it work with tree of dirs and convert png and tiff to jpg?

Answer 1

I've done something similar with converting a bitmap files to icon files here:

http://sev17.com/2011/07/creating-icons-files/

I adapted it to your requirements and test a function for converting image files to jpg:

function ConvertTo-Jpg
{
    [cmdletbinding()]
    param([Parameter(Mandatory=$true, ValueFromPipeline = $true)] $Path)

    process{
        if ($Path -is [string])
        { $Path = get-childitem $Path }

        $Path | foreach {
            $image = [System.Drawing.Image]::FromFile($($_.FullName));
            $FilePath = [IO.Path]::ChangeExtension($_.FullName, '.jpg');
            $image.Save($FilePath, [System.Drawing.Imaging.ImageFormat]::Jpeg);
            $image.Dispose();
        }
    }

 }

 #Use function:
 #Cd to directory w/ png files
 cd .\bin\pngTest

 #Run ConvertTo-Jpg function
 Get-ChildItem *.png | ConvertTo-Jpg