From: Clemens Ladisch <clemens@ladisch.de>
To: alsa-devel@alsa-project.org
Subject: Re: pcm_rate API question
Date: Mon, 30 Sep 2013 16:16:58 +0200 [thread overview]
Message-ID: <524987DA.4050800@ladisch.de> (raw)
In-Reply-To: <1380539713.33591.YahooMailNeo@web171401.mail.ir2.yahoo.com>
Rob Sykes wrote:
>>> Typically there is some buffering/delay within a resampler -- how
>>> does the pcm_rate API allow for this?
>>
>> The API itself does not allow for this. Your code must generate
>> dst_frames samples.
>>
>> At startup, prefix the output with zero samples.
>
> this situation can apparently occur at any time: "after that first
> call all subsequent calls will probably get you about 2000 samples out
> for every 1000 samples you put in" — only "probably", not "always";
> occurring after the start, this will likely cause audible distortion.
You must know your resampling algorithm. If it introduces delays, you
need to buffer more samples.
Regards,
Clemens
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prev parent reply other threads:[~2013-09-30 14:16 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-27 11:59 pcm_rate API question Rob Sykes
2013-09-27 12:38 ` Clemens Ladisch
[not found] ` <1380295697.44147.YahooMailNeo@web171405.mail.ir2.yahoo.com>
2013-09-28 9:58 ` Rob Sykes
2013-09-30 8:59 ` Clemens Ladisch
2013-09-30 11:15 ` Rob Sykes
2013-09-30 14:16 ` Clemens Ladisch [this message]
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