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+2 A:

Try redirecting the error stream to stdout like so and then you should be able to capture both stdout and stderr in a single variable e.g.:

$res = d:\video.Enc\ffmpeg.exe -i d:\video.Enc\1.wmv 2>&1

To capture the data try this:

$res | Select-String '(?ims)^Stream.*?(\d{3,4}x\d{3,4})' -all | 
    %{$_.matches} | %{$_.Groups[1].Value}

I'm not sure if $res will be one string or multiple but the above should work for both cases.

Keith Hill 2009-12-01 22:33:23

Stderr to stdout work fine. Thank you.Is there any way to obtain stderr and stdout separately ?Data capturing is bit different (there is 2 or more separated streams output info - for audio and video), there will be needed backreference or exclude for "Stream" at least, but this one point I can complete myself. Appreciated for the starting points you gave me.

Alexey Shcherbak 2009-12-02 07:43:23

Yeah you can capture them separately - ffmpeg.exe ... > foo.txt 2>foo.err

Keith Hill 2009-12-02 14:56:57

:) i wasnt completely clear :) is there any posh-way to obtain data streams separately. Ex Invoke-Expression have keys for specifying ErrorVariable and OutVariables. is there any way to acquire output using such kind of syntax, not using temporary files ?

Alexey Shcherbak 2009-12-02 16:13:36

> and 2> are Posh ways and are used far more that -ev and -ov and besides they're only available on cmdlets and not EXEs. :-) Now if you don't want to go to a file then just assigning the result of a command to a variable will capture stdout but you will still need to redirect stderr to a file (that's the easiest). `$res = ffmpeg.exe ... 2>err.txt; $err = gc err.txt` You could inspect the $error variable before and after calling ffmpeg.exe. If an error occurred (check $lastexitcode) then $error[0] should contain the stderr info.

Keith Hill 2009-12-02 16:36:58

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