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diff --git a/dvb-spec/dvbapi/audio.tex b/dvb-spec/dvbapi/audio.tex deleted file mode 100644 index 05c23e56f..000000000 --- a/dvb-spec/dvbapi/audio.tex +++ /dev/null @@ -1,454 +0,0 @@ -\devsec{DVB Audio Device} - -The DVB audio device controls the MPEG2 audio decoder of the DVB hardware. -It can be accessed through \texttt{/dev/dvb/adapter0/audio0}. -Data types and and ioctl definitions can be accessed by including -\texttt{linux/dvb/video.h} in your application. - -Please note that some DVB cards don't have their own -MPEG decoder, which results in the omission of the audio and video -device. - - -\devsubsec{Audio Data Types} - -This section describes the structures, data types and defines used when -talking to the audio device. - -\devsubsubsec{audio\_stream\_source\_t} -\label{audiostreamsource} -The audio stream source is set through the AUDIO\_SELECT\_SOURCE -call and can take the following values, depending on whether we are -replaying from an internal (demux) or external (user write) source. -\begin{verbatim} -typedef enum { - AUDIO_SOURCE_DEMUX, - AUDIO_SOURCE_MEMORY -} audio_stream_source_t; -\end{verbatim} -AUDIO\_SOURCE\_DEMUX selects the demultiplexer (fed -either by the frontend or the DVR device) as the source of -the video stream. -If AUDIO\_SOURCE\_MEMORY is selected the stream -comes from the application through the \texttt{write()} -system call. - -\devsubsubsec{audio\_play\_state\_t} -The following values can be returned by the AUDIO\_GET\_STATUS call -representing the state of audio playback. -\label{audioplaystate} -\begin{verbatim} -typedef enum { - AUDIO_STOPPED, - AUDIO_PLAYING, - AUDIO_PAUSED -} audio_play_state_t; -\end{verbatim} - -\devsubsubsec{audio\_channel\_select\_t} -\label{audiochannelselect} -The audio channel selected via AUDIO\_CHANNEL\_SELECT is determined by -the following values. -\begin{verbatim} -typedef enum { - AUDIO_STEREO, - AUDIO_MONO_LEFT, - AUDIO_MONO_RIGHT, -} audio_channel_select_t; -\end{verbatim} - -\devsubsubsec{struct audio\_status} -\label{audiostatus} -The AUDIO\_GET\_STATUS call returns the following structure informing -about various states of the playback operation. -\begin{verbatim} -typedef struct audio_status { - boolean AV_sync_state; - boolean mute_state; - audio_play_state_t play_state; - audio_stream_source_t stream_source; - audio_channel_select_t channel_select; - boolean bypass_mode; -} audio_status_t; -\end{verbatim} - -\devsubsubsec{struct audio\_mixer} -\label{audiomixer} -The following structure is used by the AUDIO\_SET\_MIXER call to set -the audio volume. -\begin{verbatim} -typedef struct audio_mixer { - unsigned int volume_left; - unsigned int volume_right; -} audio_mixer_t; -\end{verbatim} - -\devsubsubsec{audio encodings} -\label{audiotypes} -A call to AUDIO\_GET\_CAPABILITIES returns an unsigned integer with -the following bits set according to the hardwares capabilities. -\begin{verbatim} -#define AUDIO_CAP_DTS 1 -#define AUDIO_CAP_LPCM 2 -#define AUDIO_CAP_MP1 4 -#define AUDIO_CAP_MP2 8 -#define AUDIO_CAP_MP3 16 -#define AUDIO_CAP_AAC 32 -#define AUDIO_CAP_OGG 64 -#define AUDIO_CAP_SDDS 128 -#define AUDIO_CAP_AC3 256 -\end{verbatim} - - -\devsubsubsec{struct audio\_karaoke} -\label{audiokaraoke} -The ioctl AUDIO\_SET\_KARAOKE uses the following format: -\begin{verbatim} -typedef -struct audio_karaoke{ - int vocal1; - int vocal2; - int melody; -} audio_karaoke_t; -\end{verbatim} - -If Vocal1 or Vocal2 are non-zero, they get mixed -into left and right t at 70\% each. -If both, Vocal1 and Vocal2 are non-zero, Vocal1 gets -mixed into the left channel and -Vocal2 into the right channel at 100\% each. -Ff Melody is non-zero, the melody channel gets mixed -into left and right. - -\devsubsubsec{audio attributes} -\label{aattrib} -The following attributes can be set by a call to AUDIO\_SET\_ATTRIBUTES: -\begin{verbatim} -typedef uint16_t audio_attributes_t; -/* bits: descr. */ -/* 15-13 audio coding mode (0=ac3, 2=mpeg1, 3=mpeg2ext, 4=LPCM, 6=DTS, */ -/* 12 multichannel extension */ -/* 11-10 audio type (0=not spec, 1=language included) */ -/* 9- 8 audio application mode (0=not spec, 1=karaoke, 2=surround) */ -/* 7- 6 Quantization / DRC (mpeg audio: 1=DRC exists)(lpcm: 0=16bit, */ -/* 5- 4 Sample frequency fs (0=48kHz, 1=96kHz) */ -/* 2- 0 number of audio channels (n+1 channels) */ -\end{verbatim} - - -\clearpage - -\devsubsec{Audio Function Calls} - -\function{open()}{ - int open(const char *deviceName, int flags);}{ - This system call opens a named audio device (e.g. /dev/dvb/adapter0/audio0) for subsequent - use. When an open() call has succeeded, the device will be ready for use. - The significance of blocking or non-blocking mode is described in the - documentation for functions where there is a difference. It does not affect - the semantics of the open() call itself. A device opened in blocking mode can - later be put into non-blocking mode (and vice versa) using the F\_SETFL command - of the fcntl system call. This is a standard system call, documented in the - Linux manual page for fcntl. - Only one user can open the Audio Device in O\_RDWR mode. All other attempts to - open the device in this mode will fail, and an error code will be returned. - If the Audio Device is opened in O\_RDONLY mode, the only ioctl call that can - be used is AUDIO\_GET\_STATUS. All other call will return with an error code. - }{ - const char *deviceName & Name of specific audio device.\\ - int flags & A bit-wise OR of the following flags:\\ - & \hspace{1em} O\_RDONLY read-only access\\ - & \hspace{1em} O\_RDWR read/write access\\ - & \hspace{1em} O\_NONBLOCK open in non-blocking mode \\ - & \hspace{1em} (blocking mode is the default)\\ - }{ - ENODEV & Device driver not loaded/available.\\ - EINTERNAL & Internal error.\\ - EBUSY & Device or resource busy.\\ - EINVAL & Invalid argument.\\ -} - -\function{close()}{ - int close(int fd);}{ - This system call closes a previously opened audio device. - }{ - int fd & File descriptor returned by a previous call to open().\\ - }{ - EBADF & fd is not a valid open file descriptor.\\ -} - -\function{write()}{ - size\_t write(int fd, const void *buf, size\_t count);}{ - This system call can only be used if AUDIO\_SOURCE\_MEMORY is selected - in the ioctl call AUDIO\_SELECT\_SOURCE. - The data provided shall be in PES format. - If O\_NONBLOCK is not specified the function will block until buffer space is - available. The amount of data to be transferred is implied by count. - }{ - int fd & File descriptor returned by a previous call to open().\\ - void *buf & Pointer to the buffer containing the PES data.\\ - size\_t count& Size of buf.\\ - }{ - EPERM& Mode AUDIO\_SOURCE\_MEMORY not selected.\\ - ENOMEM& Attempted to write more data than the internal buffer can hold.\\ - EBADF& fd is not a valid open file descriptor.\\ -} - -\ifunction{AUDIO\_STOP}{ - int ioctl(int fd, int request = AUDIO\_STOP);}{ - This ioctl call asks the Audio Device to stop playing the current stream. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request& Equals AUDIO\_STOP for this command. - }{ - EBADF& fd is not a valid open file descriptor \\ - EINTERNAL & Internal error. -} - -\ifunction{AUDIO\_PLAY}{ - int ioctl(int fd, int request = AUDIO\_PLAY);}{ - This ioctl call asks the Audio Device to start playing an audio stream - from the selected source. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request& Equals AUDIO\_PLAY for this command. - }{ - EBADF& fd is not a valid open file descriptor \\ - EINTERNAL & Internal error. -} - -\ifunction{AUDIO\_PAUSE}{ - int ioctl(int fd, int request = AUDIO\_PAUSE);}{ - This ioctl call suspends the audio stream being played. - Decoding and playing are paused. - It is then possible to restart again decoding and playing process of the - audio stream using AUDIO\_CONTINUE command.\\ - If AUDIO\_SOURCE\_MEMORY is selected in the ioctl call - AUDIO\_SELECT\_SOURCE, the DVB-subsystem will not decode (consume) - any more data until the ioctl call - AUDIO\_CONTINUE or AUDIO\_PLAY is performed. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request& Equals AUDIO\_PAUSE for this command. - }{ - EBADF& fd is not a valid open file descriptor.\\ - EINTERNAL & Internal error. -} - -\ifunction{AUDIO\_SELECT\_SOURCE}{ - int ioctl(int fd, int request = AUDIO\_SELECT\_SOURCE, - audio\_stream\_source\_t source);}{ - This ioctl call informs the audio device which source shall be used for the - input data. The possible sources are demux or memory. - If AUDIO\_SOURCE\_MEMORY - is selected, the data is fed to the Audio Device through the write command. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_SELECT\_SOURCE for this command.\\ - audio\_stream\_source\_t source& Indicates the source that shall be used for the - Audio stream. - }{ - EBADF& fd is not a valid open file descriptor.\\ - EINTERNAL & Internal error.\\ - EINVAL & Illegal input parameter. -} - -\ifunction{AUDIO\_SET\_MUTE}{ - int ioctl(int fd, int request = AUDIO\_SET\_MUTE, boolean state);}{ - This ioctl call asks the audio device to mute the stream that is - currently being played. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_SET\_MUTE for this command.\\ - boolean state & Indicates if audio device shall mute or not.\\ - &TRUE Audio Mute\\ - &FALSE Audio Un-mute\\ - }{ - EBADF& fd is not a valid open file descriptor.\\ - EINTERNAL & Internal error.\\ - EINVAL & Illegal input parameter. -} - -\ifunction{AUDIO\_SET\_AV\_SYNC}{ - int ioctl(int fd, int request = AUDIO\_SET\_AV\_SYNC, boolean state);}{ - This ioctl call asks the Audio Device to turn ON or OFF A/V synchronization. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_AV\_SYNC for this command.\\ - boolean state& Tells the DVB subsystem if A/V - synchronization shall be ON or OFF.\\ - & TRUE AV-sync ON \\ - & FALSE AV-sync OFF\\ - }{ - EBADF& fd is not a valid open file descriptor.\\ - EINTERNAL & Internal error.\\ - EINVAL & Illegal input parameter. -} - -\ifunction{AUDIO\_SET\_BYPASS\_MODE}{ - int ioctl(int fd, int request = AUDIO\_SET\_BYPASS\_MODE, boolean mode);}{ - This ioctl call asks the Audio Device to bypass the Audio decoder and forward - the stream without decoding. This mode shall be used if streams that can't be - handled by the DVB system shall be decoded. - Dolby DigitalTM streams are automatically forwarded by the DVB - subsystem if the hardware can handle it. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_SET\_BYPASS\_MODE for this command.\\ - boolean mode& Enables or disables the decoding of the current - Audio stream in the DVB subsystem.\\ - &TRUE Bypass is disabled\\ - &FALSE Bypass is enabled\\ - }{ - EBADF& fd is not a valid open file descriptor.\\ - EINTERNAL & Internal error.\\ - EINVAL & Illegal input parameter. -} - -\ifunction{AUDIO\_CHANNEL\_SELECT}{ - int ioctl(int fd, int request = AUDIO\_CHANNEL\_SELECT, - audio\_channel\_select\_t);}{ - This ioctl call asks the Audio Device to select the requested channel - if possible. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_CHANNEL\_SELECT for this command.\\ - audio\_channel\_select\_t ch & - Select the output format of the audio (mono left/right, stereo). - }{ - EBADF& fd is not a valid open file descriptor.\\ - EINTERNAL & Internal error.\\ - EINVAL & Illegal input parameter ch. -} - -\ifunction{AUDIO\_GET\_STATUS}{ - int ioctl(int fd, int request = AUDIO\_GET\_STATUS, - struct audio\_status *status);}{ - This ioctl call asks the Audio Device to return the current state - of the Audio Device. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_GET\_STATUS for this command.\\ - struct audio\_status *status & Returns the current state of Audio Device. - }{ - EBADF& fd is not a valid open file descriptor.\\ - EINTERNAL & Internal error.\\ - EFAULT & status points to invalid address. -} - -\ifunction{AUDIO\_GET\_CAPABILITIES}{ - int ioctl(int fd, int request = AUDIO\_GET\_CAPABILITIES, - unsigned int *cap);}{ - This ioctl call asks the Audio Device to tell us about the - decoding capabilities of the audio hardware. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_GET\_CAPABILITIES for this command.\\ - unsigned int *cap & Returns a bit array of supported sound formats. - }{ - EBADF& fd is not a valid open file descriptor.\\ - EINTERNAL & Internal error.\\ - EFAULT & cap points to an invalid address. -} - -\ifunction{AUDIO\_CLEAR\_BUFFER}{ - int ioctl(int fd, int request = AUDIO\_CLEAR\_BUFFER);}{ - This ioctl call asks the Audio Device to clear all software - and hardware buffers of the audio decoder device. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_CLEAR\_BUFFER for this command. - }{ - EBADF& fd is not a valid open file descriptor.\\ - EINTERNAL & Internal error. -} - -\ifunction{AUDIO\_SET\_ID}{ - int ioctl(int fd, int request = AUDIO\_SET\_ID, int id);}{ - This ioctl selects which sub-stream is to be decoded if a program or - system stream is sent to the video device. If no audio stream type is set - the id has to be in [0xC0,0xDF] for MPEG sound, in [0x80,0x87] for - AC3 and in [0xA0,0xA7] for LPCM. More specifications may follow - for other stream types. If the stream type is set the id just - specifies the substream id of the audio stream and only the first 5 - bits are recognized. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_SET\_ID for this command.\\ - int id& audio sub-stream id - }{ - EBADF& fd is not a valid open file descriptor.\\ - EINTERNAL & Internal error.\\ - EINVAL & Invalid sub-stream id. -} - -\ifunction{AUDIO\_SET\_MIXER}{ - int ioctl(int fd, int request = AUDIO\_SET\_MIXER, audio\_mixer\_t *mix);}{ - This ioctl lets you adjust the mixer settings of the audio decoder. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_SET\_ID for this command.\\ - audio\_mixer\_t *mix& mixer settings. - }{ - EBADF& fd is not a valid open file descriptor.\\ - EINTERNAL & Internal error.\\ - EFAULT & mix points to an invalid address. -} - -\ifunction{AUDIO\_SET\_STREAMTYPE}{ - int ioctl(fd, int request = AUDIO\_SET\_STREAMTYPE, int type);}{ - This ioctl tells the driver which kind of audio stream to expect. - This is useful if the stream offers several audio sub-streams - like LPCM and AC3. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_SET\_STREAMTYPE for this command.\\ - int type & stream type\\ - }{ - EBADF& fd is not a valid open file descriptor \\ - EINVAL& type is not a valid or supported stream type.\\ -} - - -\ifunction{AUDIO\_SET\_EXT\_ID}{ - int ioctl(fd, int request = AUDIO\_SET\_EXT\_ID, int id);}{ - This ioctl can be used to set the extension id for MPEG streams in - DVD playback. Only the first 3 bits are recognized. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_SET\_EXT\_ID for this command.\\ - int id & audio sub\_stream\_id\\ - }{ - EBADF& fd is not a valid open file descriptor \\ - EINVAL& id is not a valid id.\\ -} - -\ifunction{AUDIO\_SET\_ATTRIBUTES}{ - int ioctl(fd, int request = AUDIO\_SET\_ATTRIBUTES, audio\_attributes\_t attr );}{ - This ioctl is intended for DVD playback and allows you to set - certain information about the audio stream. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_SET\_ATTRIBUTES for this command.\\ - audio\_attributes\_t attr & audio attributes according to section \ref{aattrib}\\ - }{ - EBADF& fd is not a valid open file descriptor \\ - EINVAL& attr is not a valid or supported attribute setting.\\ -} - -\ifunction{AUDIO\_SET\_KARAOKE}{ - int ioctl(fd, int request = AUDIO\_SET\_STREAMTYPE, audio\_karaoke\_t *karaoke);}{ - This ioctl allows one to set the mixer settings for a karaoke DVD. - }{ - int fd & File descriptor returned by a previous call to open().\\ - int request & Equals AUDIO\_SET\_STREAMTYPE for this command.\\ - audio\_karaoke\_t *karaoke & karaoke settings according to section \ref{audiokaraoke}.\\ - }{ - EBADF & fd is not a valid open file descriptor \\ - EINVAL& karaoke is not a valid or supported karaoke setting.\\ -} - -%%% Local Variables: -%%% mode: latex -%%% TeX-master: "dvbapi" -%%% End: |