<br><br><div><span class="gmail_quote">On 3/10/06, <b class="gmail_sendername">Marco Nelissen</b> <<a href="mailto:marcone@xs4all.nl">marcone@xs4all.nl</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
>Hi,<br>><br>>I have some low bitrate recording from my local PBS station (KQED San<br>>Francisco) in digital SD that I recorded off the Comcast cable using<br>>HD-3000. Half an hour worth of recording is about 800MB. So I calculated
<br>>the bitrate is about 1800 kbps.<br><br>If a half hour is 800 megabytes, then wouldn't that be 800*1024*8 kilobits<br>for 1800 seconds, or 3640 kilobits per second?</blockquote><div><br>:) Hadn't had my first cup of coffee when I posted this. You're right. It should be about 3600 kbps.
<br> </div><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">> MythTV is having problems playing back<br>>these recordings. It plays as if it's in slow motion. And the sound is
<br>>distorted too--shifted to lower frequency. And in the frontend log I found<br>>out that MythTV thought the recording was at 81 kbps.<br>><br>> stream: start_time: 8234.631 duration: 82875.702 bitrate=81 kb/s
<br><br>I wouldn't be surprised if kb/s actually meant kilobytes per second. Not<br>everyone is equally consistent with the use of 'k' vs 'K', 'b' vs 'B', etc.</blockquote><div><br><br>I think MythTV does report bits per second. On other recordings it would report something like 17960 kb/s. As for whether it means kilo/kibi (k/Ki), I have no idea. But for our discussion, kilo and kibi are sufficiently close to each other.
<br></div><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">It would be interesting to chop a few minutes off the start of the file<br>and try to play the remainder and see what it says about the bitrate then.
<br>Most bitrate detection problems I've come across are with variable-bitrate<br>streams where the application only looks at the first few frames to detect<br>bitrate.</blockquote><div><br>I would try your suggestion. But who should I blame for this, the broadcaster or the application, if this is indeed the problem. :)
<br></div><br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Marco<br></blockquote></div><br>DS<br>