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Frank N. Furter
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Joined: 28/05/2012
Location: Germany
Posts: 830

Posted: 08:58am 01 Dec 2023

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Hi,

I would like to set up an audio book reader.

To do this, it would be necessary to start an MP3 file at a certain point and remember this new position when stopping, as these files often have a playing time of 1/2 hour or more.

If I understand correctly, our "PLAY MP3" command can only start the file from the beginning.

Is there (another) way to start MP3 files only at a certain time index?

THANKS!!!

Frank

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 9122

Posted: 09:51am 01 Dec 2023

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You have already asked this and got no reply because, as you are presumably asking me, I have no idea and don't intend to investigate.
Why don't you do the work to look at how to construct a mp3 header and edit a mp3 file to trim it to a specified point and then insert a suitable header at the beginning of a shortened file

Frank N. Furter
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Joined: 28/05/2012
Location: Germany
Posts: 830

Posted: 01:27pm 01 Dec 2023

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Hi Peter,
thanks for your reply - I wasn't sure if you had read my entry. I was hoping there was an easier way to achieve it.
A web radio also gets a continuous stream (without a header?) and I was hoping it would be possible (with a trick) to jump to a certain point in the file to start it from there...
Thanks anyway!!!

Frank

matherp
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Posted: 02:33pm 01 Dec 2023

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AFAIK streamed mp3 is constant bitrate and each frame is self-contained and any data before a frame start will be ignored by the codec. Normal mp3 files are variable bitrate so there is no way of knowing where in the file a certain playback time will occur without reading from the beginning and essentially decoding the data as you go.

Frank N. Furter
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Joined: 28/05/2012
Location: Germany
Posts: 830

Posted: 04:21pm 01 Dec 2023

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Ok, thank you very much for your explanation! Then it won't work that easily...

matherp
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Posted: 04:23pm 01 Dec 2023

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I've had an idea - watch this space

matherp
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Posted: 05:15pm 01 Dec 2023

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Frank - see the "back to beta" thread
Edited 2023-12-02 20:10 by matherp

Frank N. Furter
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Joined: 28/05/2012
Location: Germany
Posts: 830

Posted: 08:01am 04 Dec 2023

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@Peter:

Quote V5.08.08b2

https://geoffg.net/Downloads/picomite/PicoMite_Beta.zip

Gerry: thanks for all the great testing

b2 should fix all of the above and Harm's issue (not tested). In addition I have added functionality for Frank.

PLAY HALT - stops playback for MP3 files via the VS1053 and notes the current location in the file
PLAY CONTINUE track$ - restarts playback of an mp3 track from the position halted. "track$" will be the name of the file with all file attributes removed

e.g.

PLAY MP3 "B:/mp3/mymp3.mp3"
sometime later
PLAY HALT
later again
PLAY CONTINUE "mymp3"

Thank you very much for your efforts! I can't wait to try out your new commands!