dmDVAudioHeaderGetParams(3dm)dmDVAudioHeaderGetParams(3dm)NAMEdmDVAudioHeaderGetParams - get DV audio decoder parameter values
SYNOPSIS
#include <dmedia/dm_audioutil.h>
#include <dmedia/dm_params.h>
DMstatus dmDVAudioHeaderGetParams(void *dif,
DMparams *params,
int *numSampFrames)
PARAMETER
dif Points to a valid frame of DIF data which contains embedded
audio. See dm_dv(3dm) for more info about DIF, DV, and DVCPRO.
params This params list is filled out by the function and returns
extensive information about the audio in the DIF frame.
numSampFrames
If this paramater is non-NULL, the number of 16 bit samples
embedded inside the DIF frame is returned in this parameter.
RETURNED VALUE
Returns DM_SUCCESS or DM_FAILURE.
DESCRIPTIONdmDVAudioHeaderGetParams(3dm) returns information about a single DIF
frame with many audio samples embedded in it.
The set of parameters that are returned in params are defined in
dmedia/dm_audioutil.h and are listed below:
DM_DVAUDIO_FORMAT - either DM_DVAUDIO_NTSC or DM_DVAUDIO_PAL
DM_DVAUDIO_TYPE - either DM_DVAUDIO_DV or DM_DVAUDIO_DVCPRO
DM_AUDIO_CODEC_MAX_BYTES_PER_BLOCK - either 120000 for NTSC or 144000 for
PAL
DM_AUDIO_CHANNELS - number of channels of audio (1 or 2 or 4)
DM_AUDIO_WIDTH - will always be 16
DM_DVAUDIO_CHANNEL_MODE - either DM_DVAUDIO_SD_2CH or DM_DVAUDIO_SD_4CH
DM_DVAUDIO_CHANNEL_POLICY - integer 1-19, described in dm_audioutil.h,
which specify exactly how the audio is layed out inside the DIF frame.
DM_MEDIUM - will always be DM_AUDIO
DM_AUDIO_BYTE_ORDER - will always be DM_AUDIO_BIG_ENDIAN
DM_AUDIO_FORMAT - will always be DM_AUDIO_TWOS_COMPLEMENT
DM_AUDIO_RATE - the sample rate in floating point (ex: 48000.0)
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dmDVAudioHeaderGetParams(3dm)dmDVAudioHeaderGetParams(3dm)
DM_AUDIO_CODEC_FRAMES_PER_BLOCK - the maximum number of samples this DIF
frame could possibly contain
DM_DVAUDIO_MIN_FRAMES_PER_BLOCK - the miniumum number of frames this DIF
frame could possibly contain
DM_AUDIO_CODEC_FILTER_DELAY - always zero
DM_DVAUDIO_LOCK_MODE - non-zero if audio is locked according to the DV
audio specification. Zero if it is not locked.
SEE ALSOdmDVAudioDecoderCreate(3dm), dmDVAudioDecoderSetParams(3dm),
dmDVAudioDecode(3dm).
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