Monday, June 22, 2009

Clumps of conversion

Returning to my PC last night after taking Blythe home I was surprised to find the WMA->MP3 conversion process had finished. Well, when I say finished, I mean stopped. The program thought it had reached the end of the list, but it was clear that quite a few files had been skipped.

I sorted the list by file type and removed the successfully-converted MP3 files, which reduced the list size from 2670 to 899. It sounded about right. At the estimated rate of progress I'd expected completion around 8am this morning; that number of files should have taken around 15 hours; and the program had clearly terminated while I'd been out.

I set it running again last night on those 899 files and this morning the conversion had stopped again. This time 199 files had been skipped. I repeated the process and left it running while I took Nikki to work, only to find 49 files still doggedly unconverted on my return. What is this? Some kind of binary chop? No, it seems clear that the freeware conversion tool I'd found has a bug in its list processing code. No matter, I started it off again on the 49, which first reduced to 17 and then to 6 at the fifth attempt. I ran it manually against those, one at a time and finally, shortly after 9am, the whole job was done.

Remember I said WMAs were more space hungry than MP3s? Completing this conversion has freed up 16.4GB space on my hard drive.

2 comments:

Don said...

The story as I heard it about MP3s:
1) Dump everything the human ear can't hear (or what the usual human ear can't hear).
2) If a drum and a guitar hit at the same time, and the drum drowns out the guitar, dump the guitar.
3) Follow the above principles to get rid of anything the "normal ear" can hear to arrive at the smallest file size.
Result: Sounds pretty good to most people, until they hear it alongside the original. I know people who will not listen to anything MP3'd. They say it sounds flat and uninspired.

Digger said...

Hmm. Well, if I was listening to this stuff through a pair of KEF iQ90s I might be concerned, but as it is my three main listening stations are
My PC: using bog standard Fujitsu-Siemens PC speakers
My car: using whatever passes for speakers in Vauxhall's (GM's) world
My iPod dock (Logitech MM50): probably the most accurate rendition, but still sounds fine to me.

If we ever get the media centre idea off the ground space will no longer be an issue and I'll be able to re-rip everything in a better quality format.

It'll still have to battle with my tinnitus though ;o)