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/ IRIX Base Documentation 2001 May / SGI IRIX Base Documentation 2001 May.iso / usr / share / catman / p_man / cat3dm / audio / ALgetparams.z / ALgetparams
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Text File  |  1998-10-20  |  13.0 KB  |  265 lines
  1.  
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  4. AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm))))                                              AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm))))
  5.  
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  7.  
  8. NNNNAAAAMMMMEEEE
  9.      ALgetparams, ALsetparams - (obsolete) get/set the value of the specified
  10.      audio device states
  11.  
  12. SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
  13.      ####iiiinnnncccclllluuuuddddeeee <<<<ddddmmmmeeeeddddiiiiaaaa////aaaauuuuddddiiiioooo....hhhh>>>>
  14.  
  15.      iiiinnnntttt AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((lllloooonnnngggg ddddeeeevvvviiiicccceeee,,,, lllloooonnnngggg ****PPPPVVVVbbbbuuuuffffffffeeeerrrr,,,, lllloooonnnngggg bbbbuuuuffffffffeeeerrrrlllleeeennnnggggtttthhhh))))
  16.  
  17.      iiiinnnntttt AAAALLLLsssseeeettttppppaaaarrrraaaammmmssss((((lllloooonnnngggg ddddeeeevvvviiiicccceeee,,,, lllloooonnnngggg ****PPPPVVVVbbbbuuuuffffffffeeeerrrr,,,, lllloooonnnngggg bbbbuuuuffffffffeeeerrrrlllleeeennnnggggtttthhhh))))
  18.  
  19. PPPPAAAARRRRAAAAMMMMEEEETTTTEEEERRRR
  20.      _d_e_v_i_c_e         expects the device to which this command applies.
  21.                     Currently, there is only one device, AL_DEFAULT_DEVICE.
  22.  
  23.      _P_V_b_u_f_f_e_r       expects an array of longs.  The even elements of this
  24.                     array should each contain a device state variable that you
  25.                     choose to read or change. The subsequent odd elements are
  26.                     the current or new value of these variables.
  27.  
  28.      _b_u_f_f_e_r_l_e_n_g_t_h   expects the number of longs in the buffer pointed to by
  29.                     _P_V_b_u_f_f_e_r.  This value must be even.
  30.  
  31. DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
  32.      AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss and AAAALLLLsssseeeettttppppaaaarrrraaaammmmssss are obsolete and are provided for backward
  33.      compatibility. The preferred functions are aaaallllGGGGeeeettttPPPPaaaarrrraaaammmmssss((((3333ddddmmmm)))) and
  34.      aaaallllSSSSeeeettttPPPPaaaarrrraaaammmmssss((((3333ddddmmmm)))).
  35.  
  36.      AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm)))) returns the current values for the device state
  37.      variables referenced in the _P_V_b_u_f_f_e_r array.  The values are written into
  38.      the odd locations of _P_V_b_u_f_f_e_r immediately after the corresponding state
  39.      variable.  Unrecognized parameters are ignored.
  40.  
  41.      AAAALLLLsssseeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm)))) sets the current state of the device state variables
  42.      referenced in the _P_V_b_u_f_f_e_r array. Unrecognized parameters are ignored.
  43.  
  44.      Since the audio system is a shared resource, changing the value of a
  45.      system parameter with AAAALLLLsssseeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm)))) may affect other programs
  46.      adversely.  For example, changing the input sample rate could cause an
  47.      undesired effect for a program currently sampling input data. In general
  48.      it is a good practice to determine whether other audio applications are
  49.      currently active by retrieving the number of open input/output audio
  50.      ports (see AL_INPUT_COUNT and AL_OUTPUT_COUNT below).
  51.  
  52.      The currently defined set of device parameters are defined in _a_u_d_i_o._h:
  53.      [not all parameters are present on all systems]
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  63.                                                                         PPPPaaaaggggeeee 1111
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  70. AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm))))                                              AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm))))
  71.  
  72.  
  73.  
  74.           AL_INPUT_SOURCE
  75.                AL_INPUT_LINE, AL_INPUT_MIC, or AL_INPUT_DIGITAL
  76.           AL_LEFT_INPUT_ATTEN
  77.                0 to 255 0=no attenuation, 255=maximum attenuation
  78.           AL_RIGHT_INPUT_ATTEN
  79.                0 to 255 0=no attenuation, 255=maximum attenuation
  80.           AL_INPUT_RATE
  81.                Sample rate of analog inputs. Positive values indicate sample rate
  82.                in Hz. Negative values indicate the rate value is a
  83.                logical value as opposed to a numeric one. Logical values include:
  84.                AL_RATE_AES1=set input analog sample rate to be identical to the
  85.                input digital stream sample rate. Future hardware may provide
  86.                additional logical rates.
  87.           AL_OUTPUT_RATE
  88.                Positive values indicate sample rate in Hz.
  89.                Negative values indicate the rate value is a logical value as
  90.                opposed to a numeric one. Logical values include:
  91.                AL_RATE_INPUTRATE=set output sample rate to be identical to
  92.                the input sample rate.
  93.                AL_RATE_AES1=set output sample rate to be identical to the
  94.                input digital stream sample rate.
  95.                Future hardware may provide additional logical rates.
  96.           AL_LEFT_SPEAKER_GAIN
  97.                0 to 255 0=off, 255=maximum volume.
  98.                This also affects the headphone output.
  99.           AL_RIGHT_SPEAKER_GAIN
  100.                0 to 255 0=off, 255=maximum volume
  101.                This also affects the headphone output.
  102.           AL_INPUT_COUNT
  103.                read-only.  It contains the number of open input ALports.
  104.           AL_OUTPUT_COUNT
  105.                read-only.  It contains the number of open output ALports.
  106.           AL_UNUSED_COUNT
  107.                read-only.  It contains the number of unopened ALports.
  108.           AL_SYNC_INPUT_TO_AES
  109.                _T_h_i_s _p_a_r_a_m_e_t_e_r _i_s _o_b_s_o_l_e_t_e. _0 _i_s _a_l_w_a_y_s _r_e_t_u_r_n_e_d.
  110.                1=sync to digital input clock, 0=use internal clock.
  111.           AL_SYNC_OUTPUT_TO_AES
  112.                _T_h_i_s _p_a_r_a_m_e_t_e_r _i_s _o_b_s_o_l_e_t_e. _0 _i_s _a_l_w_a_y_s _r_e_t_u_r_n_e_d.
  113.                1=sync to digital input clock, 0=use internal clock.
  114.           AL_MONITOR_CTL
  115.                Enabling monitoring causes a copy of the input stream to be
  116.                copied directly to the output of the audio system with minimal
  117.                delay. The parameter AL_MONITOR_CTL can take the following
  118.                values:
  119.                   AL_MONITOR_ON=enables monitoring of audio.
  120.                   AL_MONITOR_OFF=disables monitoring of audio.
  121.           AL_LEFT_MONITOR_ATTEN
  122.                _I_n_d_i_g_o _a_n_d _4_D/_3_5 _o_n_l_y.
  123.                   0 to 255 where 0=no attenuation and 255=maximum attenuation
  124.           AL_RIGHT_MONITOR_ATTEN
  125.                _I_n_d_i_g_o _a_n_d _4_D/_3_5 _o_n_l_y.
  126.  
  127.  
  128.  
  129.                                                                         PPPPaaaaggggeeee 2222
  130.  
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  133.  
  134.  
  135.  
  136. AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm))))                                              AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm))))
  137.  
  138.  
  139.  
  140.                   0 to 255 where 0=no attenuation and 255=maximum attenuation
  141.           AL_CHANNEL_MODE
  142.                _I_n_d_i_g_o_2 _a_n_d _I_n_d_y _o_n_l_y.
  143.                AL_STEREO=configure hardware for stereo audio.
  144.                AL_4CHANNEL=configure hardware for 4-channel audio.
  145.           AL_SPEAKER_MUTE_CTL
  146.                AL_SPEAKER_MUTE_ON=speaker and headphones muted.
  147.                AL_SPEAKER_MUTE_OFF=speaker and headphones unmuted.
  148.           AL_MIC_MODE
  149.                _I_n_d_i_g_o_2 _a_n_d _I_n_d_y _o_n_l_y.
  150.                AL_MONO or AL_STEREO
  151.           AL_DIGITAL_INPUT_RATE
  152.                _I_n_d_i_g_o_2 _a_n_d _I_n_d_y _o_n_l_y.
  153.                read-only. Positive values indicate sample rate in Hz. Negative
  154.                value indicates a logical rate (viz., AL_RATE_UNDEFINED). The
  155.                digital input rate is encoded in the input digital audio
  156.                stream, which can change over time.
  157.                Logical rates:
  158.                AL_RATE_UNDEFINED=digital input signal valid, but rate
  159.                not encoded in signal
  160.                AL_RATE_UNACQUIRED=digital input signal valid, but rate
  161.                not yet acquired from input signal
  162.                AL_RATE_NO_DIGITAL_INPUT=digital input signal not valid
  163.           AL_LEFT2_INPUT_ATTEN
  164.                _I_n_d_i_g_o_2 _a_n_d _I_n_d_y _o_n_l_y.
  165.                0 to 255 0=no attenuation, 255=maximum attenuation
  166.                This parameter is available on systems with 4-channel capability
  167.                only.
  168.           AL_RIGHT2_INPUT_ATTEN
  169.                _I_n_d_i_g_o_2 _a_n_d _I_n_d_y _o_n_l_y.
  170.                0 to 255 0=no attenuation, 255=maximum attenuation
  171.                This parameter is available on systems with 4-channel capability
  172.                only.
  173.  
  174.  
  175. EEEEXXXXAAAAMMMMPPPPLLLLEEEE
  176.                #include <dmedia/audio.h>
  177.                ...
  178.                /* Set the speaker gains to 128 */
  179.                long buf[4] = {
  180.                     AL_LEFT_SPEAKER_GAIN, 128,
  181.                     AL_RIGHT_SPEAKER_GAIN, 128
  182.                };
  183.                ALsetparams(AL_DEFAULT_DEVICE,buf,4);
  184.  
  185.  
  186.      AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm)))) and AAAALLLLsssseeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm)))) can fail for the following reasons:
  187.  
  188.      AAAALLLL____BBBBAAAADDDD____DDDDEEEEVVVVIIIICCCCEEEE             _d_e_v_i_c_e is not AL_DEFAULT_DEVICE.
  189.  
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  194.  
  195.                                                                         PPPPaaaaggggeeee 3333
  196.  
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  200.  
  201.  
  202. AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm))))                                              AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm))))
  203.  
  204.  
  205.  
  206.      AAAALLLL____BBBBAAAADDDD____PPPPVVVVBBBBUUUUFFFFFFFFEEEERRRR           _P_V_b_u_f_f_e_r is null (0) valued.
  207.  
  208.      AAAALLLL____BBBBAAAADDDD____BBBBUUUUFFFFFFFFEEEERRRRLLLLEEEENNNNGGGGTTTTHHHH____NNNNEEEEGGGG   _b_u_f_f_e_r_l_e_n_g_t_h is negative.
  209.  
  210.      AAAALLLL____BBBBAAAADDDD____BBBBUUUUFFFFFFFFEEEERRRRLLLLEEEENNNNGGGGTTTTHHHH____OOOODDDDDDDD   _b_u_f_f_e_r_l_e_n_g_t_h is odd.
  211.  
  212.      AAAALLLL____BBBBAAAADDDD____DDDDEEEEVVVVIIIICCCCEEEE____AAAACCCCCCCCEEEESSSSSSSS      audio hardware is inaccessible.
  213.  
  214. NNNNOOOOTTTTEEEE
  215.      Setting AL_LEFT_SPEAKER_GAIN or AL_RIGHT_SPEAKER_GAIN automatically sets
  216.      AL_SPEAKER_MUTE_CTL to AL_SPEAKER_MUTE_OFF.
  217.  
  218.      Setting AL_CHANNEL_MODE to AL_4CHANNEL causes the input and output sample
  219.      rates to be identical.
  220.  
  221.      When AL_CHANNEL_MODE is set to AL_4CHANNEL, the AL_INPUT_SOURCE parameter
  222.      controls the behavior of the second set of analog inputs (normally the
  223.      microphone input). In this state, the normal line-level inputs are always
  224.      active. Setting AL_INPUT_SOURCE to AL_INPUT_MIC causes the second set of
  225.      inputs to be mic-level. Setting AL_INPUT_SOURCE to AL_INPUT_LINE causes
  226.      the second set of analog inputs to be line-level.
  227.  
  228. DDDDIIIIAAAAGGGGNNNNOOOOSSSSTTTTIIIICCCCSSSS
  229.      Upon successful completion, AAAALLLLggggeeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm)))) and AAAALLLLsssseeeettttppppaaaarrrraaaammmmssss((((3333ddddmmmm)))) return
  230.      0. Otherwise, these functions return -1 and set an error number which can
  231.      be retrieved with oooosssseeeerrrrrrrroooorrrr((((3333CCCC)))).
  232.  
  233.  
  234. SSSSEEEEEEEE AAAALLLLSSSSOOOO
  235.      ALqueryparams(3dm), ALgetminmax(3dm), ALgetdefault(3dm), ALgetname(3dm),
  236.      oserror(3C)
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  261.                                                                         PPPPaaaaggggeeee 4444
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