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Slightly later than usual:

The Radio 4 Extra listing for the seven days beginning 29/07/17 has been posted at the following permanent link:

This contains the online listing and the pdf: hover the mouse over the 'pdf' button and right-click and 'save as' to download, or left-click to display and then possibly print through the pdf viewer.

The rtf version is no longer produced, but there is a printer-friendly html version under the 'print-frendly' button; download and viewing is as per the procedure above for the pdf.

An archive is being built up - see the 'archive' button. Archive versions are also available under the 'print-friendly' button.

Note that the online version now lands on the current programme; to read next week's list early, use the 'Archive' drop-down list.
Geek Speak / Re: Download 384 kbps LIVE stream
« Last Post by ilainftw on July 31, 2017, 11:11:04 PM »
You are confusing download speed with audio bitrate. Just because you are downloading HLS chunks faster than >320k doesn't mean the encoded audio is >320k. If you are downloading an HLS on-demand stream or a live stream with a rewind buffer, then of course ffmpeg will download as fast as it needs to (upstream permitting) to do whatever transcoding you have configured. Without a rewind buffer, HLS live stream downloading settles near the nominal audio bit rate. The BBC doesn't give you >320k audio just because you ask for it (but you're really not doing that). The BBC doesn't give you MPEG-2 or WAV audio just because you ask for it (but you're really not doing that either).  When you think about how HLS streams are produced, and how the BBC provides only one stream per variant playlist, that wouldn't make any sense. You only get apparently higher bitrates in your output files because you're transcoding and upsampling the audio stream after it is downloaded. Prove it to yourself by downloading a 320k live stream with no transcoding:
Code: [Select]
ffmpeg -i URL -c copy file.ts then check the audio bit rate in the resulting file. It will contain 320k audio. Do the same with a 320k on-demand stream, which will show the same result.
Radio Programmes - Info \'n\' Reviews / Eddie Mair's PM 27/07/17 Radio4
« Last Post by Ed on July 31, 2017, 05:17:35 PM »
I used the link which you posted, and the programme played without any problem.

I'm in the UK, and my experience might be different to listeners overseas, as a consequence of recent BBC changes to iPlayer. (Has there ever been a time when the phrase 'due to recent BBC changes to iPlayer' did not end my every sentence?)

Listeners to iPlayer should note my recent thread, here:

Your listening experience may be worse currently, due to you being intentionally blocked by some of the recent changes. My post explains some counter-measures you can take to resolve the problem.

Geek Speak / Download 384 kbps LIVE stream
« Last Post by Ed on July 31, 2017, 05:03:12 PM »
Your comments are interesting, but I believe you are wrong.

I have the ability to monitor the audio stream itself, and to measure its bitrate. There are various software tools which include this capability. My tests establish that ffmpeg is actually fetching a 384 kbps bitrate stream.

Let's try the easiest test. I'm running Windows 7: for anyone using it, and interested in carrying out a test, all you need do is right-click on the Desktop task bar, then click 'start task manager'.

The 'Networking' tab in Task Manager will show the bitrate of the incoming stream: both as a visual graph, and (in the column 'Bytes Received per Interval') as a number. It's important to only have a single stream download running when you're doing this test (otherwise you'll see the combined data for all running streams).

It's quite good fun to take one of my .mp2 download methods, and run it with Task Manager open so you can watch the results. Then change the .mp2 extension to .wav and re-run the test: watch the incoming rate shoot up from 384 kbps to 1,500 kbps !

(Whatever figures you're seeing will quadruple, as will the average height of the visual display graph. Because these are 'chunked' streams, the audio is delivered in discontinuous chunks, for reliability, not as a continuous steady stream at 384 kb/sec, so what you see is an average, rising and falling, not a steady line.)

Not that I recommend downloading the uncompressed .wav stream, because it gives you a gigantic file size. But it makes a powerful demonstration of my point.

@ilainftw : I'd be interested to know what software you are using to measure the bitrate. Perhaps it's something I can run in Windows 7 ?
You are very welcome! :)
Radio Programmes - Info \'n\' Reviews / Re: Eddie Mair's PM 27/07/17 Radio4
« Last Post by Truthyness on July 29, 2017, 08:20:01 PM »
Wow, thanks so much Jim.
 8) :-* ;D
Hi Truthy, have hopefully just sent file to your Gmail address, will message tomorrow to catch up.

Radio Programmes - Info \'n\' Reviews / Eddie Mair's PM 27/07/17 Radio4
« Last Post by Truthyness on July 29, 2017, 02:53:33 AM »
Can anyone help with Listen Again for Eddie Mair's PM of 27/7/17.
An "unavailable to listen in your area" window pops up. Nothing doing at all after many attempts.

Thank you very much.
Geek Speak / Re: Download 384 kbps LIVE stream
« Last Post by ilainftw on July 27, 2017, 04:01:55 PM »
Although the above described method does work, I was never happy with it, because the audio stream which it accesses is unstable.
Those are Shoutcast streams, which are likely to be less reliable than the HLS HTTP-based chunked audio streams.
Here, then, is the new method for forcing the live stream to run at 384 kbps, instead of at the standard bitrate of 320 kbps.
That is not what you are doing. The audio stream remains 320k AAC (or 128k in your first example). You are merely instructing ffmpeg to transcode it to MPEG-2 when saving to a file. 384k is the default bit rate used by ffmpeg for MP2 encoding, so you're just upsampling the source audio. It's OK if you prefer that output, but for most people it will suffice to save the AAC stream as-is into an MPEG-TS file (perhaps with remux to M4A for final recording). Transcoding (usually to MP3) would only absolutely be required if you have a hardware player that doesn't support AAC audio or can't handle large AAC files (from lengthy recordings).
Use any of these four command lines (each is actually a 2-line command line) -
In general, it's better to use the variant playlists, e.g.:
Code: [Select] than the stream playlists they contain, e.g.:
Code: [Select] stream playlists may change over time. Each variant playlist for BBC radio contains only a single stream, so no danger of getting an unexpected bit rate.
R4 Extra (The Station Formerly Known As R7) Matter / Re: Lives of Harry Lime ?
« Last Post by Truthyness on July 27, 2017, 01:03:46 AM »
You know Ed I've a strange sense of Déjà Vue here ... from earlier broadcasts of that episode.
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