----- Original Message -----
From: "Graham Newton" <[log in to unmask]>
> Tom Fine wrote:
>> Finally had a chance to listen to both MP3 files. One man's opinion here,
>> but the de-thumping was too radical to my ears. It creates annoying gaps
>> in the music and makes the surface noise that's left pump so it's
>> actually more noticeable. Did you try a notch filter at the loudest
>> frequency of the thumps? I'd bet there's not much necessary music content
>> down that low in the bandwidth of a tight notch. That might make the
>> thumps less noticeable than the gaps and pumping are with the thumps
>> That said, it's pretty amazing you were able to paste that thing back
>> together and play it. The little ditty isn't half bad either.
> As much as I hate to admit it, I've had CEDAR's de-thump and re-touch
> processes for some years but problems with how the earlier SADiE hardware
> and software platform handled things caused me to put it on the back
> With the new SADiE v5 software and related hardware, the problems were
> eliminated, and this example was my first effort at applying the processes
> under these conditions. This was primarily for demonstrating the de-thump
> process and yes, further improvements could definitely be made by applying
> additional processes like CEDAR's NR-4.
> Over that roughly 3 minute track, there were a little less than 200
> individual de-thump edits and some were arguably better than others, but
> on the whole, the result shows what can be done with severely damaged
> source materials.
> This process is manually intensive since it can't be automated and hence
> is an expensive proposition that demands a decision on whether the rarity
> of the source material justifies the cost of the work to be applied to it.
> The example disc was one of a very few of these known to exist, so it was
> justifiable, certainly as a test subject.
> CEDAR's de-thump process, as I said, is manual and involves marking the
> extent of the thump on the workstation oscillographic display, then
> telling CEDAR how many cycles of thump exist in the marked area. De-thump
> then looks at material on either side of the marked area and constructs
> what it thinks would be the missing material in the marked area, and
> substitutes that in the space. If the operator is wrong on the number of
> thump cycles, it will affect what it substitutes to one degree or another,
> and audibly to the critical listener.
> All told however, the process is pretty remarkable and allows corrections
> to be made without the timeline being affected.
And I reply from a position of effective ignorance...!
It would seem to me that there are two possible approaches here...?!
1) IF the record is "un-rare" enough that other copies are known to
exist...simply play an extant copy, open a "waveform" version of that
sound recording, play the broken and repaired copy, and substitute
segments of the "intact" waveform where "blanks" exist...!
2) IF the broken-and-repaired copy is the ONLY extant copy of
an extremely rare phonorecord...play that copy, open a "waveform
view" of the result, and manually "fill in the blanks"...with, if nothing
else, a straight line connecting both sides of the "gap"...?!
Is this, in fact, possible...?!
Steven C. Barr