Re: Missing data fragments when custom headers set

Dnia 2019-11-24, o godz. 10:21:07
tangram67 via curl-library <curl-library_at_cool.haxx.se> napisał(a):

> Hi to all.
>
> I'm using libcurl as a receiver for MP3 radio streams.
> When using custom headers in conjunction with header and body data
> callbacks, some data is missing in the data callbacks. This is also
> reproducable when using the following command line:
>
> curl --header "Icy-MetaData: 1" -sD - -o ./ndr1.mp3
> http://ndr-edge-2061.dus-lg.cdn.addradio.net/ndr/ndr1niedersachsen/hannover/mp3/128/stream.mp3
>
> If you play the resulting MP3 file with some kind of media player you
> can hear dropdowns caused by missing data. If you remove the custom
> header, then the stream is OK. Also this behaviour is independant of the
> header value, so any header string will cause the problem.
>

Hi Dirk,

What makes you think the dropdowns are caused by missing data?

You requested the server to multiplex metadata with the MP3 stream.
You can't send such a stream directly to MP3 decoder. Instead,
your client needs to extract "icy-metaint:" response header and demux
the stream appropriately (extract the metadata instead of sending
them to MP3 decoder). Otherwise you're periodically feeding the decoder
with garbage.

Please cross-check your results with a client which doesn't use libcurl, e.g.
wget -S --header "Icy-MetaData: 1" -O ndr2.mp3 http://ndr-edge-2061.dus-lg.cdn.addradio.net/ndr/ndr1niedersachsen/hannover/mp3/128/stream.mp3

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