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Subject: Re: Summer of Code 2009

Re: Summer of Code 2009

From: Andreas Stemmer <groovingandi_at_gmx.de>
Date: Tue, 20 Jan 2009 19:04:53 +0100

Paul Louden wrote:
> I really must be confused. I remember "audible seeking" as being more or
> less an automated seek-listen-seek. It's clear we're talking about
> something different here, or I can't see how one method would be any
> more effective than the other.
>
> What, exactly, is being described here?

Historically, "audible seeking" would be just speeding up playback, probably at something like 500% just like any tape deck did it thirty years ago. As you pointed out in your other message, this can be achieved by just setting the pitch to 200%. However, 200% are not enough for useful searching and the user interface would have to get mapped to the FFW/REV keys.

Recent music players (CDs or MP3s) implement the feature differently, they use an automated seek-listen-seek as you describe, but with really tiny steps - like skipping 1 second, playing 1/10th etc. It "feels" like speeding up playback without changing the pitch. In contrast to the first method, this has the benefit that there's no need to decode the complete MP3 stream, only small snippets. Compared to manual seek-listen-seek, you still have the feeling of continous output, so accidently jumping over the passage you wanted is unlikely.

I just checked with the original H340 firmware and it uses the second method. If you want, I can record the output of the player and try to find out how the jumps/snippet size relate exactly.

For me, any method would be fine - whatever is easier to implement.

Andreas
Received on 2009-01-20


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