When I’m preparing Blu-ray vs DVD comparisons, my process these days is to rip most or all of the ‘I’ frames from the Blu-ray first, organise them, then select the comparison frames and rip DVD frames to match those. That’s because it’s a lot easier to step around DVD video streams than Blu-ray ones, and tools for capturing a selected frame from a Blu-ray are rare and clunky.

So the Blu-ray ripping process often leaves me with some ten to fifteen thousand still images on my hard disc, most of them between one and two megabytes in size. In order to aid in the selection process it is necessary to use a ‘Thumbnail’ view, but I find that Windows gets increasingly clunky with this, the more files there are in any folder. So I create a sufficient number of folders so that each only has to hold a thousand files.

A problem has been the time it takes to move the files into their respective folders. Recently I had one particularly daunting prospect of nearly 20,000 files, so I decided to do it a different way. It was a bit extra effort at the start, but the results could be reused time and time again.

To do it I used the DOS Batch capability. DOS is the old white text and black screen that has existed since before the days of the IBM PC. It became popular with that platform, but in fact the Microsoft Disc Operating System was very similar in operation to CP/M.

Batch files are essentially a list of DOS commands in a text file, the name of which ends in .BAT. You can type in the file name and it will run the commands one after the other.

The application I use to rip frames from the Blu-ray names the files in this form: 00006007.png. As you would expect, the number that forms the file name is incremented by one for each additional file. So the commands for moving the files are easy.

First, I create a folder one level down from the folder holding all the files:

md 06

Then I move files from 6000 to 6999 to it:

move 00006*.png 06

Simply have a list of these, replacing the ‘6’ with first ‘0’, then ‘1’ and so on up to the necessary number.

The purpose of all this was to allow me to type one simple command in the DOS box and then go away while the computer did the work, rather than dragging a thousand files, waiting until that was done, dragging another thousand files and so on.

What surprised me, though, was how quickly the batch file was completing. I’ve just finished this process with First Blood. To test my time impressions I deployed the stop watch. I dragged a block on 999 files into a folder and then timed how long it took to complete: 35.8 seconds. Then I ran the BAT for the remaining 8692 files within a DOS box. That took 27.0 seconds to complete.

That meant that DOS was more than a magnitude of order quicker in doing the ‘move’ than Windows. Why would Windows be so horribly inefficient?

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