| 1 | .TH "roar_vs_stream" "3" "June 2011" "RoarAudio" "RoarAudio Programmer's Manual" |
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| 2 | |
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| 3 | .SH NAME |
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| 4 | roar_vs_stream \- Set up stream parameters for VS object |
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| 5 | |
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| 6 | .SH SYNOPSIS |
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| 7 | |
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| 8 | #include <roaraudio.h> |
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| 9 | |
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| 10 | int roar_vs_stream(roar_vs_t * vss, const struct roar_audio_info * info, int dir, int * error); |
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| 11 | |
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| 12 | .SH "DESCRIPTION" |
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| 13 | This function asks a VS object opened by \fBroar_vs_new_from_con\fR(3) or \fBroar_vs_new\fR(3) |
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| 14 | to open the data connection using the audio parameters \fBinfo\fR and the stream direction \fBdir\fR. |
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| 15 | |
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| 16 | This function needs to be called before data is read or written if one of the above functions is used |
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| 17 | to create the VS object. |
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| 18 | |
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| 19 | This function is also used to provide parameters for the file mode |
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| 20 | (which is started by using \fBroar_vs_file\fR(3) or \fBroar_vs_file_simple\fR(3)). |
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| 21 | To play back a file this is not needed in a common case as the VS API tries to find correct parameters. |
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| 22 | It is required for all other stream directions. See \fBroar_vs_file\fR(3) and \fBroar_vs_file_simple\fR(3) |
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| 23 | for more information. |
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| 24 | |
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| 25 | On failture this function can be called again with diffrent parameters. |
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| 26 | |
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| 27 | .SH "PARAMETERS" |
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| 28 | .TP |
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| 29 | \fBvss\fR |
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| 30 | The VS object to be updated. |
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| 31 | |
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| 32 | .TP |
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| 33 | \fBinfo\fR |
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| 34 | This is a pointer to the roar_audio_info structure storing the audio format parameters. |
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| 35 | The structure contains the following memebers: |
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| 36 | rate (sample rate), bits (bits per sample), channels (channels per frame) and codec. |
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| 37 | |
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| 38 | .TP |
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| 39 | \fBdir\fR |
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| 40 | This is the stream direction. Common values include ROAR_DIR_PLAY for waveform playback, |
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| 41 | ROAR_DIR_MONITOR for waveform monitoring, ROAR_DIR_RECORD for waveform recording. |
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| 42 | For MIDI ROAR_DIR_MIDI_IN and ROAR_DIR_MIDI_OUT is used. |
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| 43 | |
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| 44 | .TP |
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| 45 | \fBerror\fR |
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| 46 | This is a pointer to a integer used to store the error value in case of error. |
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| 47 | This can be NULL if not used but it is very recommended to use this error value to report |
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| 48 | good error messages to the user. |
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| 49 | |
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| 50 | .SH "RETURN VALUE" |
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| 51 | On success these calls return 0. On error, \-1 is returned. |
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| 52 | |
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| 53 | .SH "EXAMPLES" |
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| 54 | struct roar_audio_info info; |
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| 55 | int err; |
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| 56 | |
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| 57 | if ( roar_profile2info(&info, "isdn-eu") == -1 ) { |
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| 58 | // error handling. |
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| 59 | } |
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| 60 | |
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| 61 | if ( roar_vs_stream(vss, &info, ROAR_DIR_PLAY, &err) == -1 ) { |
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| 62 | // error handling. |
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| 63 | } |
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| 64 | |
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| 65 | .SH "SEE ALSO" |
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| 66 | \fBroar_vs_file\fR(3), |
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| 67 | \fBroar_vs_file_simple\fR(3), |
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| 68 | \fBroarvs\fR(7), |
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| 69 | \fBlibroar\fR(7), |
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| 70 | \fBRoarAudio\fR(7). |
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| 71 | |
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| 72 | .\" ll |
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