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Reply With QuoteCool. Thanks. Will be interested to see how your code compares with mine. I'm in a DAB+ only area (Australia).
I've attached my code as far as I have got. The FM generally seems to work and DAB is at least playing channels (though only DAB ... no DAB+ or other stuff). It should give anyone who's interested a general idea of how the radio stick API works. There are still some issues ... mostly around me being too lazy to free COM objects and reconnecting the filters (and thus some channels play at wierd speeds). Oh, and it's all a bit of a mess!
Edit - I put the code on GitHub instead of attaching it. Never used Git before (only SVN) but it seems to be working.
Last edited by alnicol; 03-01-2012 at 04:42 AM.
Cool. Thanks. Will be interested to see how your code compares with mine. I'm in a DAB+ only area (Australia).
We have DAB and DAB+( Australia) just depends on the device used. Good to see this is finally getting somewhere. Thanks guysOriginally Posted by Shonky*
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Where in Australia is DAB broadcast? How does it depend on the device used?
Excellent ... DAB+ seems to be almost the same as DAB but with a couple of additional filters. Have you tried playing DAB+ with the example app which came with the SDK? It looks like users need an AAC decoder from a third party ... what do you use? The ffdshow one?
I'm going to rewrite my filter graph building stuff to be a bit more intelligent. When it switches channel it needs to reconnect the graph depending on whether it's DAB, DAB+ or something else (possibly packet data etc).
Dab is the same as DAB+. The only difference is that DAB+ allows you to pause/rewind and record live broadcasts etc(extra data) where as a DAB device does not. It just recieves and plays DAB. Its sort of like having 2 FM radios. One with RDS capability and the other one does not have RDS but both play FM. The one that has RDS is just capable or receiving extra data/signals broadcasted from the radio station like the stations name and such. But the base signal is FM.
No. DAB is MPEG2 whereas DAB+ is AAC. A DAB only radio cannot necessarily receive DAB+ and many older DAB radios are not even upgradeable.
Australia uses only DAB+
Wouldn't this be a feature of the device rather than of DAB/DAB+? The audio is streamed live and any pausing/rewinding is down to the device buffering the data. I think Shonky is correct ... it's mainly the audio codec change, and also the way the error correction is done (which makes DAB barely usable in weak signal areas).
Your confusing DAB with Digital Radio which is transmitted over DVB or DTV band which is MPEG2. And as you said DAB+ and OR DAB is AAC more efficient and better sound quality. Dab+ has more band width over the signal allowing more data to be sent and received like weather/traffic updates. Your right that a DAB device cannot be upgraded to DAB+. In Sydney we started with DAB then shortly after we went to DAB+. DAB as the base but a wider band width for more info for devices with DAB+. I didnt mean any controversy. I just bought 2 devices that can only receive DAB but work very well . One of them i sent to a member of this site to try to get it to work with CF but i wont mention his name but he has posted a number of times on this particular thead. Again, i didnt mean to stir any sh#t. Forget i brought it up
Look I don't want to derail this too much, but most of that is incorrect.
I'm not confusing audio channels on DVB multiplexes. Yes they are MPEG II (2).
DAB is MPEG I Layer 2 (MP2 in the same sense that MP3 is abbreviated that way). DAB+ is HE-AAC which is about 3-4 times more efficient.
DAB and DAB+ have exactly the same RF channel bandwith of 1.536MHz. This equates to something like 1000kbit/s of data. DAB+ gets better quality (or more channels) in the same amount of bandwidth because of the better compression of HE-AACv2.
Not sure which DAB devices you have and work in Sydney but that's not what Australia uses. What channels do you receive on a DAB only device?
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