diff options
Diffstat (limited to 'dvb-spec/dvbapi/audio.tex')
| -rw-r--r-- | dvb-spec/dvbapi/audio.tex | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/dvb-spec/dvbapi/audio.tex b/dvb-spec/dvbapi/audio.tex index 8c5b4fe82..e81dd2f89 100644 --- a/dvb-spec/dvbapi/audio.tex +++ b/dvb-spec/dvbapi/audio.tex @@ -354,7 +354,12 @@ typedef uint16_t audioAttributes_t; \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. + 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.\\ @@ -382,7 +387,7 @@ typedef uint16_t audioAttributes_t; 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 MPEG2 audio and AC3. + like LPCM and AC3. }{ int fd & File descriptor returned by a previous call to open().\\ int request & Equals AUDIO\_SET\_STREAMTYPE for this command.\\ @@ -395,7 +400,8 @@ typedef uint16_t audioAttributes_t; \ifunction{AUDIO\_SET\_EXT\_ID}{ int ioctl(fd, int request = AUDIO\_SET\_EXT\_ID, int id);}{ - This ioctl can be used to set the audio sub\_stream\_id for DVD playback + 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.\\ |