Celestin Apprentice 2/Apprentice-Release2.iso/Information/Digests/CSMP Digest/volume 1/csmp-v1-210.txt

Text File | 1994-12-08 | 52.0 KB | 1,345 lines | [TEXT/R*ch]

C.S.M.P. Digest             Sun, 08 Nov 92       Volume 1 : Issue 210

Today's Topics:

    Sound Manager



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-------------------------------------------------------

From: [e-mail] (Ed Watkeys)
Subject: Sound Manager
Date: 18 May 92 11:57:29 GMT
Organization: Distant Software

Is there some trick to installing voices in a sampledSynth channel? I've been
playing, and I can't seem to avoid a bus error. This is what I'm doing more
or less:

    mySample = GetResource('snd ',19000);
    if (mySample == NULL || ResErr)
        ExitToShell;

    HLock(mySample);

    myCmd.cmd = soundCmd;
    myCmd.param1 = 0;
    myCmd.param2 = (long) *mySample;

    if (SndDoCommand(myChannel,&myCmd,false) <> noErr)
        ExitToShell;

    myCmd.cmd = freqDurationCmd;
    myCmd.param1 = 2000;
    myCmd.param2 = 60;

    /* and I get a bus error in this line: */
    if (SndDoCommand(myChannel,&myCmd,false) <> noErr)
        ExitToShell;

What I'm doing is very simple, and a lot of my code is IM VI code translated
into C. I have a channel open at this point, using IM VI sample code. If I
change sampledSynth to the square wave synth and remove the code to install
a voice, everything works fine.

Also, does anyone know if there are tech notes dealing with the Sound Manager?
If so, are they post-IM VI, or do they cover information that was out into
IM VI?

Thanks loads,
Ed

- --
Ed Watkeys (Drexel U. Comp Sci)  "Moral judgement and condemnation is
[e-mail]              the favorite form of revenge for the
[e-mail]      spiritually limited on those who are
ls.com!phlpa!caligula!edw         less so...." -- Friedrich Nietzsche

+++++++++++++++++++++++++++

From: [e-mail] (Jim Reekes)
Date: 19 May 92 19:42:59 GMT
Organization: Apple Computer, Inc.

In article <[e-mail]>, [e-mail] (Ed Watkeys) writes:
>
> Is there some trick to installing voices in a sampledSynth channel? I've been
> playing, and I can't seem to avoid a bus error. This is what I'm doing more
> or less:
>
>     mySample = GetResource('snd ',19000);
>     if (mySample == NULL || ResErr)
>         ExitToShell;
>
>     HLock(mySample);
>
>     myCmd.cmd = soundCmd;
>     myCmd.param1 = 0;
>     myCmd.param2 = (long) *mySample;
>
>     if (SndDoCommand(myChannel,&myCmd,false) <> noErr)
>         ExitToShell;
>
>     myCmd.cmd = freqDurationCmd;
>     myCmd.param1 = 2000;
>     myCmd.param2 = 60;
>
>     /* and I get a bus error in this line: */
>     if (SndDoCommand(myChannel,&myCmd,false) <> noErr)
>         ExitToShell;
>
> What I'm doing is very simple, and a lot of my code is IM VI code translated
> into C. I have a channel open at this point, using IM VI sample code. If I
> change sampledSynth to the square wave synth and remove the code to install
> a voice, everything works fine.
>
> Also, does anyone know if there are tech notes dealing with the Sound Manager?
> If so, are they post-IM VI, or do they cover information that was out into
> IM VI?
>
> Thanks loads,
> Ed

1. You don't point at the 'snd ' resource for the soundCmd.  You pass a
pointer to the sound header contained within the resource.

SoundApp demonstrates how to do all of this.  It's official MacDTS sample
code.  It's been available for a few years.  Inside Mac VI is the only
documentation to read.  The rest is covered in the sample code.


- -----------------------------------------------------------------------
Jim Reekes, Polterzeitgeist  |     Macintosh Toolbox Engineering
                             |          Sound Manager Expert
Apple Computer, Inc.         | "All opinions expressed are mine, and do
20525 Mariani Ave. MS: 81-KS |   not necessarily represent those of my
Cupertino, CA 95014          |       employer, Apple Computer Inc."

+++++++++++++++++++++++++++

From: [e-mail] (David Sugar)
Date: 6 Jun 92 04:49:16 GMT
Organization: Drexel University, Dept. of Math. and Comp. Sci.


  I have what I hope is a farily simple question on using a Sound Manager
call.  The call in question is SPBGetDeviceInfo.  I am having trouble when
I use either the selector siActiveChannels or siActiveLevels.  I have
read the little description in IM VI many time and I don't understand
what it means by "When setting the active channels, the data passed in
is a long integer etc...  I keep getting the error back of -231.  But
any of the other calls that I make with different selectors are ok.
  I have already opened the sound input device with no problem and have
the refNum and I can get the number of channels and all that stuff, but
not this ActiveChannels or ActiveLevels.  Here is what I have right now,
keep in mind that I'm just doing some playing around with it right now,
I will be adding error checking etc in when I get the basic stuff to actually
work.

void GetMiscInfo(long refNum)
{
    OSErr      err;
    int      chav,chan,lmet,lmac;
    long    chac;

   lmet=1;
   chac=0x00000000;  /*???  I did this just becuase I wasn't sure what to do*/
    err=SPBGetDeviceInfo(refNum,siChannelAvailable,(char) *)&chav); /*works*/
    if (chav >=2)
        chan=2;
    else
        chan=1;
    err=SPBSetDeviceInfo(refNum,siNumberChannels,(char *)&chan); /*works*/
    err=SPBSetDeviceInfo(refNum,siLevelMeterOnOff,(char *)&lmet); /*works*/
    err=SPBSetDeviceInfo(refNum,siDeviceBufferInfo,(char *)&chac);  /* error */
   err=SPBGetDeviceInfo(refNum,siActiveLevels,(char *)&lmac); /* error */
}

  Of the 2 lines that get errors I have a feeling that the second one, the
call to siActiveLevels is becuase the active channels wasn't set correctly
in the previous call.  But, I'm not sure how to set the varialbe chac etc
to get it to work..
  Does anyone have any idea on what I'm doing wrong??

  Thanks

  Dave Sugar
  [e-mail]

+++++++++++++++++++++++++++

From: [e-mail] (Jim Reekes)
Date: 9 Jun 92 07:33:33 GMT
Organization: Apple Computer, Inc.

In article <[e-mail]>, [e-mail] (David Sugar) writes:
>
>
>   I have what I hope is a farily simple question on using a Sound Manager
> call.  The call in question is SPBGetDeviceInfo.  I am having trouble when
> I use either the selector siActiveChannels or siActiveLevels.  I have
> read the little description in IM VI many time and I don't understand
> what it means by "When setting the active channels, the data passed in
> is a long integer etc...  I keep getting the error back of -231.  But
> any of the other calls that I make with different selectors are ok.
>   I have already opened the sound input device with no problem and have
> the refNum and I can get the number of channels and all that stuff, but
> not this ActiveChannels or ActiveLevels.  Here is what I have right now,
> keep in mind that I'm just doing some playing around with it right now,
> I will be adding error checking etc in when I get the basic stuff to actually
> work.
>
> void GetMiscInfo(long refNum)
> {
>     OSErr      err;
>     int      chav,chan,lmet,lmac;
>     long    chac;
>
>    lmet=1;
>    chac=0x00000000;  /*???  I did this just becuase I wasn't sure what to do*/
>     err=SPBGetDeviceInfo(refNum,siChannelAvailable,(char) *)&chav); /*works*/
>     if (chav >=2)
>         chan=2;
>     else
>         chan=1;
>     err=SPBSetDeviceInfo(refNum,siNumberChannels,(char *)&chan); /*works*/
>     err=SPBSetDeviceInfo(refNum,siLevelMeterOnOff,(char *)&lmet); /*works*/
>     err=SPBSetDeviceInfo(refNum,siDeviceBufferInfo,(char *)&chac);  /* error */
>    err=SPBGetDeviceInfo(refNum,siActiveLevels,(char *)&lmac); /* error */
> }
>
>   Of the 2 lines that get errors I have a feeling that the second one, the
> call to siActiveLevels is becuase the active channels wasn't set correctly
> in the previous call.  But, I'm not sure how to set the varialbe chac etc
> to get it to work..
>   Does anyone have any idea on what I'm doing wrong??

Never, never, EVER, pass a type int to the Mac toolbox.  In MPW the int
is four bytes long, but in Think C they used to be two bytes.  With the
new version of Think they can be either two or four bytes depending on
your preferences.

The proper thing to pass each of these selectors are:

siChannelAvailable     short
siNumberChannels       short
siLevelMeterOnOff      short
siDeviceBufferInfo     long
siActiveLevels         long

The next thing is that error -231 means the selector is not supported,
thus the name "siUnknownInfoType".

So, if you get the error it means it's not going to work with the current
driver.  The Apple Sound Input driver does not support setting either
siDeviceBufferInfo or siActiveLevels.

Below are some examples of calling SPBGetDeviceInfo and SPBSetDeviceInfo.


long GetBufferLength(void)
{
    long       bufferLength;
    OSErr       err;

    err = SPBGetDeviceInfo(gSndInputRef, siDeviceBufferInfo, (Ptr)&bufferLength);
    if (err == noErr)                         // noErr
        return (bufferLength);
    else
        return (0);
}

short GetVoxStopData(void)
{
    short       VoxData[3];
    OSErr       err;

    err = SPBGetDeviceInfo(gSndInputRef, siVoxStopInfo, (Ptr)VoxData);
    if ( (err == noErr) && (VoxData[0]) )           // noErr and Vox Stop is on
        return (VoxData[1]);
    else
        return (0);
}

void SetVoxStop(short value)
{
    short       VoxData[3];
    OSErr       err;

    if (value > 0)
        VoxData[0] = 1;                             // turn it on
    else
        VoxData[0] = 0;                             // turn it on
    VoxData[1] = value;
    VoxData[2] = GetVoxDelayData();
    err = SPBSetDeviceInfo(gSndInputRef, siVoxStopInfo, (Ptr) VoxData);
    if (err)
        AlertUser(err, eSndInMgr, !kFatalError);
}

void SetVoxDelay(short value)
{
    short       VoxData[3];
    OSErr       err;

    VoxData[0] = 1;                                 // turn it on
    VoxData[1] = GetVoxStopData();
    VoxData[2] = value;
    err = SPBSetDeviceInfo(gSndInputRef, siVoxStopInfo, (Ptr) VoxData);
    if (err)
        AlertUser(err, eSndInMgr, !kFatalError);
}

short GetVoxDelayData(void)
{
    short       VoxData[3];
    OSErr       err;

    err = SPBGetDeviceInfo(gSndInputRef, siVoxStopInfo, (Ptr)VoxData);
    if ( (err == noErr) && (VoxData[0]) )           // noErr and Vox Stop is on
        return (VoxData[2]);
    else
        return (0);
}

short SetLevelMetering(Boolean on)
{
    OSErr           err;
    short           metering;

    if (on)
        metering = 1;                             // turn it on
    else
        metering = 0;                             // turn it off
    err = SPBSetDeviceInfo(gSndInputRef, siLevelMeterOnOff, (Ptr)&metering);
    if (err)
        AlertUser(err, eSndInMgr, !kFatalError);
}

short GetCurLevel(void)
{
    OSErr           err;
    short           meterData[2];

    err = SPBGetDeviceInfo(gSndInputRef, siLevelMeterOnOff, (Ptr) meterData);
    if ((err == noErr) && meterData[0])         // no error and level metering on
        return (meterData[1]);
    else
        return (0);
}



- -----------------------------------------------------------------------
Jim Reekes, Polterzeitgeist  |     Macintosh Toolbox Engineering
                             |          Sound Manager Expert
Apple Computer, Inc.         | "All opinions expressed are mine, and do
20525 Mariani Ave. MS: 81-KS |   not necessarily represent those of my
Cupertino, CA 95014          |       employer, Apple Computer Inc."



+++++++++++++++++++++++++++

From: [e-mail] (Chuck McMath)
Date: 11 Jun 92 19:05:12 GMT
Organization: MSD

I have a MacApp/Sound Manager problem that is driving me craaaazy!

I *thought* I understood how the Sound Manager worked, but there's one
sticky point with which I am having problems.  My application records
audio using the standard sound input routines, and the audio can be
uncompressed or compressed 3:1 or 6:1.  No problem there.  I save
it to a file.  Now, I want to play back arbitrary portions of it,
based on a user selection.  The standard technique for playing
an audio selection doesn't suffice, since you can only specify
'play from X seconds in the audio to Y seconds' and I need more
granularity than that.  So here's how I do it:

    1. When play is selected, determine start and stop
              bytes of the audio

    2. Create a sound channel. For uncompressed it's like this:
            FailOSErr(SndNewChannel(gSCPtr, sampledSynth, initMono, @MarkBuffersFree));
        Otherwise it's like this:
            FailOSErr(SndNewChannel(gSCPtr, sampledSynth, initMono + initMACE3 + initMACE6, ...
        Call SetupSndHeader with the proper parameters for my audio buffers

    3. Play audio using a number of buffers:
        3a. Read audio data from file and shove into current audio buffer.
        3b. Schedule a callback.  When it gets called, it simply
                marks the buffer as 'available' once more.
        3c. Go back to 3a until audio is done.

    <Note: step 3 is done using MacApp's Idle mechanism>

    4. When audio is done, kill the channel.

    Here FINALLY is the problem:  when I play audio that was recorded
at 3:1 or 6:1 compression this technique works great.  However, when I
play audio that was recorded uncompressed, you can (faintly) hear the
original audio, but you hear LOUD scratches/noise.  The question:
what's going on, and how can I fix this problem?

 A solution that doesn't involve me changing all 8.5 million lines of
code for this project would be a good one :).

    Any ideas would be appreciated!

    Thanks!

    chuck

                       --chuck mcmath-
                    [e-mail]
  MSD, Inc. * National Library of Medicine * National Institutes of Health
                       Bethesda, MD 20894

          "Hey batter, hey batter, hey batter, swing" - Anon.

+++++++++++++++++++++++++++

From: [e-mail] (John Miller)
Date: Wed, 17 Jun 1992 16:24:06 GMT
Organization: Eastern Illinois University

Hi All,

The situation:  I've created a shell to explore musical playback using the
Sound Manager.  A simple melody is successfully played back on a Mac II
using System 7 using each of the three synths--sampled, square, and
wave-table, compiled and run separately.

The problem:  The same program running on a Plus and an SE under 6.0.5,
6.0.7, and 6.0.8 is successful playing back the sampled and square-wave
example, but has strange results when using the wave-table synth--the
example does not start at the beginning, and occasional other
irregularities (wrong octave) result.

Any advice?

Thanks in advance


John


- --
John Miller
Music Theory
Eastern Illinois University

+++++++++++++++++++++++++++

From: [e-mail] (Paul Potts)
Organization: Instructional Technology Laboratory, University of Michigan
Date: Wed, 17 Jun 92 21:59:19 GMT

In article <[e-mail]> [e-mail] (John Miller) writes:
>Hi All,
>
>The situation:  I've created a shell to explore musical playback using the
>Sound Manager.  A simple melody is successfully played back on a Mac II
>using System 7 using each of the three synths--sampled, square, and
>wave-table, compiled and run separately.
>
>The problem:  The same program running on a Plus and an SE under 6.0.5,
>6.0.7, and 6.0.8 is successful playing back the sampled and square-wave
>example, but has strange results when using the wave-table synth--the
>example does not start at the beginning, and occasional other
>irregularities (wrong octave) result.

First off, I wouldn't attempt to do much with the sound manager under 6.0.5.
Stick with 6.0.7 or above, which has a later version.

The wave-table synth is a little weird, but I've had some luck with it.
You aren't trying to pass it real frequency values, are you? Use only MIDI
note values. Passing real frequency values will cause strange results.
The documentation was wrong about this for some time, but I-M 7 has it
right.

Other than that, maybe post some code?


- --
The essence of OOP: "With all this horse manure, I know there's got to be
                     a pony in here somewhere!"
Paul R. Potts, Software Designer --- [e-mail] <--- me!

+++++++++++++++++++++++++++

From: [e-mail] (Jim Reekes)
Date: 25 Jun 92 01:05:03 GMT
Organization: Apple Computer, Inc.

In article <[e-mail]>, [e-mail] (John Miller) writes:
>
> Hi All,
>
> The situation:  I've created a shell to explore musical playback using the
> Sound Manager.  A simple melody is successfully played back on a Mac II
> using System 7 using each of the three synths--sampled, square, and
> wave-table, compiled and run separately.
>
> The problem:  The same program running on a Plus and an SE under 6.0.5,
> 6.0.7, and 6.0.8 is successful playing back the sampled and square-wave
> example, but has strange results when using the wave-table synth--the
> example does not start at the beginning, and occasional other
> irregularities (wrong octave) result.
>
> Any advice?
>

The wave table channels do not work on "classic" hardware not running the
new Sound Manager.  These are the Plus, SE, or Classic under a system
older than 6.0.7.  Also, you should try your code under System 7.0.
I'm certain that 7.0 sound manager is going to work for you.

"Make is suck less" is the motto.

- -----------------------------------------------------------------------
Jim Reekes, Polterzeitgeist  |     Macintosh Toolbox Engineering
                             |          Sound Manager Expert
Apple Computer, Inc.         | RAll opinions expressed are mine, and do
20525 Mariani Ave. MS: 81-KS |   not necessarily represent those of my
Cupertino, CA 95014          |       employer, Apple Computer Inc.S



+++++++++++++++++++++++++++

From: [e-mail] (Walt Davis)
Date: 8 Jul 92 22:42:11 GMT
Organization: Alcatel Network Systems, Raleigh NC

I'm new in sound-programming game and I'm having problems getting some
of my simple, asynchronous (or synchronous for that matter) sound
manager code to behave properly on 68000-based SEs and Pluses.  All I'm
trying to do is play little 'snd ' resources (type 1) on sampledSynth
sound channels.  Everything works fine on IIs and up.  Obviously I'm
missing something obvious.  I suspect some type of sound-manager
incompatibilities (couldn't be me ;-)).  SOS...

Walt Davis
[e-mail]
AOL: DavisW

+++++++++++++++++++++++++++

From: [e-mail] (Mark Lanett)
Date: 9 Jul 92 07:20:58 GMT
Organization: Apple Computer Inc., Cupertino, CA

[e-mail] (Walt Davis) writes:

>I'm new in sound-programming game and I'm having problems getting some
>of my simple, asynchronous (or synchronous for that matter) sound
>manager code to behave properly on 68000-based SEs and Pluses.  All I'm
>trying to do is play little 'snd ' resources (type 1) on sampledSynth
>sound channels.  Everything works fine on IIs and up.  Obviously I'm
>missing something obvious.  I suspect some type of sound-manager
>incompatibilities (couldn't be me ;-)).  SOS...

Try hardware incompatibilities. Pluses and SEs don't have the sound chip
required for some things like play from disk and playing multiple sound
channels. Having only spent 3 days or so tinkering with the Sound Manager I'm
not clear on what exactly won't work, however.
- --
Have a bajillion brilliant Jobsian lithium licks.
Mark Lanett

+++++++++++++++++++++++++++

From: [e-mail] (Jamie R. McCarthy)
Organization: Kalamazoo College
Date: Thu, 9 Jul 1992 13:07:52 GMT

[e-mail] (Mark Lanett) writes:
>[e-mail] (Walt Davis) writes:
>
>>I'm new in sound-programming game and I'm having problems getting some
>>of my simple, asynchronous (or synchronous for that matter) sound
>>manager code

"Simple, asynchronous sound manager code" is oxymoronic...

>>to behave properly on 68000-based SEs and Pluses.  All I'm
>>trying to do is play little 'snd ' resources (type 1) on sampledSynth
>>sound channels.  Everything works fine on IIs and up.  Obviously I'm
>>missing something obvious.  I suspect some type of sound-manager
>>incompatibilities (couldn't be me ;-)).
>
>Try hardware incompatibilities. Pluses and SEs don't have the sound chip
>required for some things like play from disk and playing multiple sound
>channels.

There are many and various things which can go wrong when you try to
play sound.  I don't think we can blame anything in particular at this
point.

Mark, make sure you're using the same system on all machines;  6.0.7 or
7 would be best.  Don't use Macintalk or SoundMaster, and don't run any
applications that use the Sound Driver.  And post the code you're using;
pseudo-code is OK if it's accurate.
- --
 Jamie McCarthy      Internet: [e-mail]      AppleLink: j.mccarthy
 I suppose ya don't think I was run over by a streetcar!

+++++++++++++++++++++++++++

From: [e-mail] (Mark Hayes)
Date: 9 Jul 92 16:34:10 GMT
Organization: Boston University, Boston, MA, USA

Since there's been some more discussion recently about sound problems,
I'd like to re-present a problem I mentioned a while ago, with some new
information, and again ask if anyone knows why things go as they do.

This little test program runs just dandy on my SE/30 under System 7.0;
it plays an (uncompressed) 'snd' resource ten times and exits.
If, however, I run it on an SE/30 under System 6.0.7, or on an SE under 7.0,
the sound plays once and only once. Here's the code:

    void main(void)
    {
    OSErr myErr; SndChannelPtr myChanPtr; Handle myHandle; short x;

    myChanPtr = nil;
    myErr = SndNewChannel(&myChanPtr, 0, 0L, nil);
    myHandle = GetNamedResource('snd ', "\pmySound");

    for (x = 0; x < 10; x++)
        myErr = SndPlay(myChanPtr, myHandle, false);

    myErr = SndDisposeChannel(myChanPtr, true);
    }

Now, if I change the program so that it doesn't allocate and retain a
channel across multiple SndPlay calls, it works on all three systems:

    for (x = 0; x < 10; x++)
        myErr = SndPlay(nil, myHandle, false);

I know Apple recommends that one *not* retain a channel in the way I want to,
but there definitely is a performance hit in the second program that I'd prefer
to avoid. In the real programs I'm working on, I do de- and re-allocate the
channel in the event of a suspend/resume, or if my own code puts up a dialog.
And the sound plays are synchronous, so it's not (?) a timing problem.
So why does this first sample program work on the System 7 SE/30 but not
on the other two systems?

Also, while I'm here, what, please, are the system and machine requirements
for the use of compressed sounds with SndPlay? I believe I'm talking about
a capability called "MACE", but I don't know what systems support it and what
systems don't.

Thanks to anyone for any help.
                                                              Mark

+++++++++++++++++++++++++++

From: [e-mail] (Jamie R. McCarthy)
Organization: Kalamazoo College
Date: Thu, 9 Jul 1992 18:07:32 GMT

[e-mail] (Mark Hayes) writes:
>
>This little test program runs just dandy on my SE/30 under System 7.0;
>it plays an (uncompressed) 'snd' resource ten times and exits.
>If, however, I run it on an SE/30 under System 6.0.7, or on an SE under 7.0,
>the sound plays once and only once. Here's the code:
>
>    ...
>    myChanPtr = nil;
>    myErr = SndNewChannel(&myChanPtr, 0, 0L, nil);
>    for (x = 0; x < 10; x++)
>        myErr = SndPlay(myChanPtr, myHandle, false);
>    myErr = SndDisposeChannel(myChanPtr, true);
>    ...
>
>Now, if I change the program so that it doesn't allocate and retain a
>channel across multiple SndPlay calls, it works on all three systems:
>
>    for (x = 0; x < 10; x++)
>        myErr = SndPlay(nil, myHandle, false);
>
>I know Apple recommends that one *not* retain a channel in the way I want to,

They do?  I couldn't find that in IM VI...

But if so, then listen to Apple and don't do it!

>but there definitely is a performance hit in the second program that I'd prefer
>to avoid.

Don't use SndPlay, then.  Instead, do this with the channel:

SndCommand s;
s.cmd = flushCmd;
FailOSErr(SndDoImmediate(myChanPtr, &s));
s.cmd = quietCmd;
FailOSErr(SndDoImmediate(myChanPtr, &s));
HLock(myHandle);
s.cmd = bufferCmd;
s.param2 = StripAddress(*myHandle) + offsetToStartOfSndBuffer(myHandle);
FailOSErr(SndDoCommand(myChanPtr, &s, TRUE));
// keep the handle locked until the sound completes

You'll have to write the function offsetToStartOfSndBuffer() yourself.
It's a ten-line no-brainer that takes a handle and returns the offset to
the start of the sound buffer, which is _not_ the raw data, it's what
immediately follows the sound commands in the 'snd ' resources.

>Also, while I'm here, what, please, are the system and machine requirements
>for the use of compressed sounds with SndPlay? I believe I'm talking about
>a capability called "MACE", but I don't know what systems support it and what
>systems don't.

You need the system 6.0.7 or later Sound Manager to use MACE.  It stands
to reason that MACEVersion() would return nonzero if MACE is present,
but don't hold me to that.  My system 7.0.1 returns "1.0.1 final".
- --
 Jamie McCarthy      Internet: [e-mail]      AppleLink: j.mccarthy
 When the ship runs out of water and the vessel runs aground, land's where we
 know the boat is found.  Now, there's nothing unexpected about the water
 giving out;  "land"'s not a word we have to shout.  -- TMBG, "Women and Men"

+++++++++++++++++++++++++++

From: [e-mail] (Jamie R. McCarthy)
Date: 10 Jul 92 13:54:43 GMT
Organization: Kalamazoo College

[e-mail] (Jamie R. McCarthy) writes:
>[e-mail] (Mark Hayes) writes:
>>
>>I know Apple recommends that one *not* retain a channel in the way I want to
>
>They do?  I couldn't find that in IM VI...

Then, [e-mail] (Walt Davis) advises me via email:
>
>See IM VI page 22-40...

Aha.  The actual warning is "...sound channels are for temporary use,
and...you should create them just before playing sounds.  Once the sound
is completed, you should dispose of the channel."

Don't take this warning _too_ seriously.  Most programs should follow
it, because it's good advice:  if you keep a sampledSynth sound channel
open continuously, the user will never hear a "Simple Beep" SysBeep,
because it uses a different synthesizer.  That's just one reason why you
should close sound channels when you don't need them.

But when you do need them, don't be stingy.  If you need to play ten
noisess in a row, there's absolutely no reason why you shouldn't keep one
channel open for all ten noises.  If your arcade game has lots of sound,
keep as many channels open as you need.  Now, when the player switches you
into the background, or otherwise pauses the action, then you should
dispose of them.  But there's no reason to get in a frenzy of religiously
allocating and disposing SndChannels every time you play a sound.
- --
 Jamie McCarthy      Internet: [e-mail]      AppleLink: j.mccarthy
 When the ship runs out of water and the vessel runs aground, land's where we
 know the boat is found.  Now, there's nothing unexpected about the water
 giving out;  "land"'s not a word we have to shout.  -- TMBG, "Women and Men"

+++++++++++++++++++++++++++

From: [e-mail] (Paul Potts)
Date: 10 Jul 92 20:04:15 GMT
Organization: Instructional Technology Laboratory, University of Michigan

In article <[e-mail]> [e-mail] (Mark Lanett) writes:
>[e-mail] (Walt Davis) writes:
>
>>I'm new in sound-programming game and I'm having problems getting some
>>of my simple, asynchronous (or synchronous for that matter) sound
>>manager code to behave properly on 68000-based SEs and Pluses.  All I'm
>>trying to do is play little 'snd ' resources (type 1) on sampledSynth
>>sound channels.

There aren't any compatibility problems that would make it impossible to
play a type 1 sound on a 68000-based machine. It does work - or else how would
you be able to use a cow mooing or whatever for your system beep?

Show us some code... maybe we can get a better idea that way. Keep in mind that
it is possible a bug elsewhere could cause a crash when you call the
sound manager. Are you checking all the error returns properly? There are
things that you can't do with sound on the low-end macs, but the sound manager
will usually tell you.

- --
..though I respect that a lot, I'd be fired if that were my job, after
killing Jason off and countless screaming argonauts... (They Might Be Giants)
Paul R. Potts, Software Designer --- [e-mail] <--- me!

+++++++++++++++++++++++++++

From: Daniel E. Rudman <[e-mail]>
Date: Fri, 17 Jul 92 03:34:07 EDT
Organization: The University of Michigan Ann Arbor

In article <[e-mail]> Mark Hayes, [e-mail] writes:

>    void main(void)
>    OSErr myErr; SndChannelPtr myChanPtr; Handle myHandle; short x;
>    myChanPtr = nil;
>    myErr = SndNewChannel(&myChanPtr, 0, 0L, nil);
>    myHandle = GetNamedResource('snd ', "\pmySound");
>    for (x = 0; x < 10; x++)
>        myErr = SndPlay(myChanPtr, myHandle, false);
>    myErr = SndDisposeChannel(myChanPtr, true);
>    }

I don't know if this helps, but I don't think it's a really good idea to call
SndNewChannel with 0 as your synth and your modifier; I think you should
probably use sampleSynth and monoWhateverTheHellItIs or whatever. Zero is not
defined in Inside Mac VI, and I wouldn't suggest using it. I've had problems
with the Sound Manager when trying that.

Also, if you ever plan on coming BACK to that section of the code (not in
this case, obviously, but you never know) then make sure you FORCE THE
CHANNEL POINTER TO NIL. SndNewChannel doesn't work so well when you pass it
the remains of your disposed channel. Anyway, that doesn't happen here but I
thought I'd mention it.

- ------------------------------------------------------------
Daniel E. Rudman
The University of Michigan
Computer-Aided Engineering Network

+++++++++++++++++++++++++++

From: [e-mail] (Danny W. McCampbell)
Date: 10 Aug 92 19:57:22 GMT
Organization: University of Tennessee

I want to thank those who responded to my question about playing simple
sounds from within my program.  Now I have more questions.  If I
understand IM Vol. VI correctly I can call SndStartFilePlay I can
control the sound the way I want to.  Right now I am just using
SndPlay to play the sound and everything works fine except that I
cannot proceed to do anything else until the sound (which is extremely
large) finishes playing.  I want to be able to let the sound play
while I continue to do things within program.  I tried using
SndStartFilePlay but the error that it returns is -201 which is
Insufficient hardware available.  I have a MacII CI with 8 megs of
ram and plenty of hard disk space.  Is there something specific
that I have to have like a microphone jack to call SndStartFilePlay?
If anyone out there has some code laying around that would help me
better understand what I am doing, I would greatly appreciate getting
a look at it.  I am just merely calling a modal dialog, starting a
sound and waiting for the user to click OK.  When they click OK I want
to stop the sound and close the dialog.

Thanks in advance.

Sorry for being so ignorant.

Danny McCampbell
[e-mail]

+++++++++++++++++++++++++++

From: [e-mail] (Ian Neath)
Date: 10 Aug 92 20:21:39 GMT
Organization: Psychology Department, Purdue University

I recall a while back a mention about the Sound Manager chapter
in IM 6 that implied it had been superseded.  Is this correct?
If so, where can I find how to play SND s asynchronously under
System 7?  I've found that my System 6 async code plays
synchronously under 7.  If it is accurate, I'd appreciate knowing
that also.

Thanks.

- --
    Ian Neath, PhD     | There are four kinds of people in this world:
[e-mail] | cretins, fools, morons and lunatics - U. Eco

+++++++++++++++++++++++++++

From: [e-mail] (Chuck Hoffman)
Date: 1 Sep 92 19:55:02 GMT
Organization: GTE Laboratories

I'm just getting into the Sound Manager and am using the simple note
synthesizer.  I created a sound resource with ResEdit (created my own 'snd
' template) and the sound plays fine from ResEdit and my program.  Playing
asynchronously.  When the sound is done, I have a CallBackCmd to invoke my
callback routine which simply sets a flag so that I can later dispose of
the channel and release the sound resource.  I've done this by putting the
callback command at the end of the sound resource, and by using
SndDoCommand to insert into the buffer.  In both cases, it works correctly
about 2 of 3 times.  Can't set a THINK C debugger breakpoint in the
callback routine because of crashes (a conflict with the memory manager?),
but the main event loop sees the variable as if it has not been set.  I've
tried code updating the flag (in a global variable) directly, and I've
tried passing the address of the variable to the subroutine and getting at
it that way.  Same symptom no matter what.  Any ideas?


Chuck Hoffman
[e-mail]
GTE Laboratories, Waltham, Massachusetts, USA
[phone]
=====================================
I'm not sure why we're here, but I am sure that while we're here we're
supposed to help each other.
=====================================

+++++++++++++++++++++++++++

From: [e-mail] (Daniel Norman Johnson)
Organization: Rensselaer Polytechnic Institute, Troy, NY.
Date: Thu, 1 Oct 1992 18:35:27 GMT

I am having a problem with an extension I am writing. This extension
is really a background app (type='appe'), which plays sounds asynchronously
in the background (which sounds are specified with annother program, that
works);

Most of the time it works fine but I am having 2 odd problems that I haven't
been able to track down.

One sound that I have, namely "Spanish Inquisition" ("<BLAM> NOOOOOOOBody
expects the Spanish Inquisition!") Is giving me trouble. This sound
plays synchronously just fine. Asynchronously, it SOMETIMES plays
fine. When the appe is running as an APPL (so I can double
click it+ don't have to restart to fool with it), it plays fine.
When my app is running as an appe (ie normally) the sound plays
but the extension then freezes up. Everything else continues
working fine, but the extension will not play anything or respond
to apple events (notably 'QUIT'- something of a pain when u r trying
to Shut Down); This strange freeze happens on a friends LC whenever
the sound is played, even  from an APPL. (but only if its
asynchronously)

The other problem seems to be an incompatibility with AutoDoubler,
versions 1.0.6 and 1.0.7 at least. On my friend's LC it cannot
play Autodoubler compressed sounds. The whole system freezes if its
tries to do so, but only if I am not trying to use the Think Pascal
debugger on it. :( So I dont know exactly what's happeneing; maybe
the sound is freezing when it loads or something. Is there a known
bug in AutoDoubler that could do this? This bug does not occur
on my system, at all.

I am writing this in Think Pascal 4.0, on a Macintosh IIcx 5/100. I
am using AutoDoubler 1.0.7 (my friend was using 1.0.6, but I got him
the update thinking that would solve the problem. It didn't.) My
friends LC was a 4/40 btw.

Thanx in advance!

- --
            - Dan Johnson
And God said "Jeeze, this is dull"... and it *WAS* dull. Genesis 0:0

These opinions have had all identifiying marks removed, and are untraceable.
You'll never know whose they are.

+++++++++++++++++++++++++++

From: [e-mail]
Organization: BMUG, Inc.
Date: Fri, 02 Oct 1992 20:41:03 PDT

I ran into similar sound problems (in an 'appl' only) where I needed to
play an async sound repeatedly (machine gun type effect). All sound on
my LC would stop after a few cycles of the sound. I found that by adding
a slight delay (3 - 6 ticks) before trying to replay the sound
everything was fine. Perhaps this will help your situation...?
***************************************************************************
             From Planet BMUG, the FirstClass BBS of BMUG, Inc.
              The above message was gatewayed via PostalUnion
***************************************************************************
The message contained in this posting is entirely the poster's personal
opinion.  Any possible, real or perceived, (dis)similarities with the
views held by BMUG, are purely coincidental.
***************************************************************************

+++++++++++++++++++++++++++

From: [e-mail] (Dan Schwarz)
Date: 5 Oct 92 02:27:12 GMT
Organization: Brandeis University

In article <w=[e-mail]> [e-mail] writes:
>I am having a problem with an extension I am writing. This extension
>is really a background app (type='appe'), which plays sounds asynchronously
>in the background (which sounds are specified with annother program, that
>works);
...
>This strange freeze happens on a friends LC whenever
>the sound is played, even  from an APPL. (but only if its
>asynchronously)

Speaking as a programmer who has done some SERIOUS sound manager hacking,
I can sympathize with your frustration. Here's what I can tell you:

* the Mac LC uses a crippled version of the Apple Sound Chip. So does the LC II
and Classic II, by the way. Major difference is that this chip can only handle
monophonic sound output, and cannot support simultaneous sound recording &
playback.

* the System 6.0.7 and 6.0.6 sound managers have MAJOR bugs, especially when
dealing with the LC. These systems' sound input managers were taken directly
from alpha versions of System 7.0 (in the rush to ship the first LC and IIsi
units.) Don't trust the Gestalt values they return, for example.

* Use 7.0 or later versions, but this won't solve all your problems. I am
convinced that there are hardware or software bugs in Apple's handling of
this particular sound chip. For example, play back a QuickTime movie with
sound (in SimplePlayer or any similar product.) Switch out of the layer
into a product which does sound recording or otherwise uses the sound manager.
Switch back. Odds are, the sound will be silenced upon returning to the QT
movie. I don't know how to solve this problem.

Unless the "delay" tactic mentioned earlier is successful, the only thing
you can do is to complain to MacDTS until you get a reasonable response.
They're not very forthcoming about Mac sound internals, but be specific with
your problem and maybe you can get a workaround.

_Dan

+++++++++++++++++++++++++++

From: [e-mail] (Jamie R. McCarthy)
Organization: Kalamazoo College
Date: Mon, 5 Oct 1992 13:09:14 GMT

[e-mail] (Dan Schwarz) writes:
>
>* the Mac LC uses a crippled version of the Apple Sound Chip. So does the LC II
>and Classic II, by the way. Major difference is that this chip can only handle
>monophonic sound output, and cannot support simultaneous sound recording &
>playback.

Hmmm.  Well, the preliminary developer note for the LC (I seem to have
lost the final :-) says it "implements a subset of the ASC," but I think
it would more accurately be described as really simple hardware and a
Sound Manager that tries to make up for it.

Another difference is that the LC doesn't support the 4-channel
wavetable mode, which is part of the ASC.  (But does the Sound Manager
recognize an ASC and use it for 4-channel wavetables?  Theoretically,
four waveTableSynth channels should take almost no CPU time.  Has anyone
checked this out?)

Later, it says "The sound system is similar to the Plus and SE sound
systems in that main memory is used for the sound buffer.  Because the
Macintosh LC computer's video modes have different line times...the
sound system has its own timing chain, which samples at the same
rate..."  Later it explains that this stuff is built into the V8 gate
array, which appears to be a catch-all custom chip to do a hodgepodge of
things that lots of little chips used to take care of.  (You can see by
my language that I'm not a hardware person.  :-)

Anyway, it looks like "subset of the ASC" is misleading.  I'd call it a
"simulation of the chintzy RAM-sampling technique used by the original
128K Mac, plus sound input, all tied together by the much-overworked
Sound Manager."

Can anyone who knows more about the LC, and hardware in general, expound
on this?

>* the System 6.0.7 and 6.0.6 sound managers have MAJOR bugs, especially when
>dealing with the LC.

Well, I don't know about the LC in particular, but those sound managers
in general are a _lot_ more trustworthy than in previous versions.

>Unless the "delay" tactic mentioned earlier is successful, the only thing
>you can do is to complain to MacDTS until you get a reasonable response.

I was going to suggest using a custom double-buffering routine, but I've
never done it myself so I can't give advice.  I'd try that before
calling up MacDTS though.
- --
 Jamie McCarthy      Internet: [e-mail]      AppleLink: j.mccarthy
 "I don't think we should have to have them wandering the streets
  frightening women and people."                            - Pat Buchanan

+++++++++++++++++++++++++++

From: [e-mail] (Daniel Norman Johnson)
Date: 5 Oct 92 15:34:34 GMT
Organization: Rensselaer Polytechnic Institute, Troy, NY.

In article <[e-mail]>, [e-mail] (Dan Schwarz) writes:
|> In article <w=[e-mail]> [e-mail] writes:
|> >I am having a problem with an extension I am writing. This extension
|> >is really a background app (type='appe'), which plays sounds asynchronously
|> >in the background (which sounds are specified with annother program, that
|> >works);
|> ...
|> >This strange freeze happens on a friends LC whenever
|> >the sound is played, even  from an APPL. (but only if its
|> >asynchronously)
|>
|> Speaking as a programmer who has done some SERIOUS sound manager hacking,
|> I can sympathize with your frustration. Here's what I can tell you:
|>
|> * the Mac LC uses a crippled version of the Apple Sound Chip. So does the LC II
|> and Classic II, by the way. Major difference is that this chip can only handle
|> monophonic sound output, and cannot support simultaneous sound recording &
|> playback.

Im just using SndPlay(blah,blah,True); to do this; It should be monophonic
and (for these sounds) just ordinary sampled sound. I think.

|> * the System 6.0.7 and 6.0.6 sound managers have MAJOR bugs, especially when
|> dealing with the LC. These systems' sound input managers were taken directly
|> from alpha versions of System 7.0 (in the rush to ship the first LC and IIsi
|> units.) Don't trust the Gestalt values they return, for example.

I don't. I dont even call Gestalt, and I dont use sound Input. Could you
be a little more specific about the bugs, that is any bugs that might
louse up asynchronous sound playback?

|> * Use 7.0 or later versions, but this won't solve all your problems. I am
|> convinced that there are hardware or software bugs in Apple's handling of
|> this particular sound chip. For example, play back a QuickTime movie with
|> sound (in SimplePlayer or any similar product.) Switch out of the layer
|> into a product which does sound recording or otherwise uses the sound manager.
|> Switch back. Odds are, the sound will be silenced upon returning to the QT
|> movie. I don't know how to solve this problem.

Bleah. No, make that Double-bleah.

|> Unless the "delay" tactic mentioned earlier is successful, the only thing
|> you can do is to complain to MacDTS until you get a reasonable response.
|> They're not very forthcoming about Mac sound internals, but be specific with
|> your problem and maybe you can get a workaround.

Ill try to boost the delay, but it already has some delay in it- specificly
it calls WaitNextEvent so it cant start the next sound until that comes
back (which should be good for a few ticks, anyway.) So I dont know about
that. (I cant do it right now, cuz my roommates asleep. :( )

In any case, the latest version of it always closes the sound channel and opens
it again before each sound. This has teh spiffy effect that it can now
plays sounds after the Spanish Inquisition (but that does not play). So its
getting better. No progress on teh autodoubler problem tho.

- --
            - Dan Johnson
And God said "Jeeze, this is dull"... and it *WAS* dull. Genesis 0:0

These opinions have had all identifiying marks removed, and are untraceable.
You'll never know whose they are.

+++++++++++++++++++++++++++

From: [e-mail] (Daniel Norman Johnson)
Organization: Rensselaer Polytechnic Institute, Troy, NY.
Date: Mon, 5 Oct 1992 15:37:50 GMT

In article <[e-mail]>, [e-mail] (Jamie R. McCarthy) writes:
|> [e-mail] (Dan Schwarz) writes:
|> >
[deletia- details on LC ASC]
|>
|> >Unless the "delay" tactic mentioned earlier is successful, the only thing
|> >you can do is to complain to MacDTS until you get a reasonable response.
|>
|> I was going to suggest using a custom double-buffering routine, but I've
|> never done it myself so I can't give advice.  I'd try that before
|> calling up MacDTS though.

Waitaminute. I thot double buffering was a trick you could do
to play direct from disk... if not, what is it?

- --
            - Dan Johnson
And God said "Jeeze, this is dull"... and it *WAS* dull. Genesis 0:0

These opinions have had all identifiying marks removed, and are untraceable.
You'll never know whose they are.

+++++++++++++++++++++++++++

From: [e-mail] (Jamie R. McCarthy)
Date: 6 Oct 92 10:32:39 GMT
Organization: Kalamazoo College

[e-mail] (Lawrence D'Oliveiro, Waikato University) writes:
>(Jamie R. McCarthy) writes:
>>
>> Well, I don't know about the LC in particular, but [the 6.0.6&7 SMs]
>> in general are a _lot_ more trustworthy than in previous versions.
>
>I know of one major snag with the 6.0.7 Sound Manager. ...  I had a brief
>chance to check it myself, and discovered that it was dying in the resume loop.
>
>Idea: perhaps it has something to do with spurious invocation of my callback
>routine. I recall Jim Reekes mentioning that this was possible, though I
>don't recall what the precise conditions were.

Someone else mentioned once that your callback can get called
inappropriately under 6.0.4 (or was it .5?), so I always check in my
routines.  (My technique, for what it's worth, is to put an identifying
constant in param1 and my app's A5 in param2.)

If you can get that 4-voice-harmony XCMD to work under 6.0.7, Lawrence,
a lot of people in the music-education biz would be very grateful.  :-)
- --
 Jamie McCarthy      Internet: [e-mail]      AppleLink: j.mccarthy
 Memo to myself:
 Do The Dumb Things I Gotta Do.
 Touch The Puppet Head.

+++++++++++++++++++++++++++

From: [e-mail] (Jamie R. McCarthy)
Organization: Kalamazoo College
Date: Tue, 6 Oct 1992 12:49:41 GMT

[e-mail] writes:
>Jamie R. McCarthy writes:
>> I was going to suggest using a custom double-buffering routine, but I've
>> never done it myself so I can't give advice.  I'd try that before
>> calling up MacDTS though.
>
>Waitaminute. I thot double buffering was a trick you could do
>to play direct from disk... if not, what is it?

To quote IM VI 22-72:  "The play-from-disk routines make extensive use
of the SndPlayDoubleBuffer function.  ...  By using SndPlayDoubleBuffer
...you can specify your own doubleback procedure (that is, the algorithm
used to switch back and forth between buffers) and customize several
other buffering parameters.  Note:  SndPlayDoubleBuffer is a very
low-level routine and is not intended for general use.  You should use
SndPlayDoubleBuffer only if you require very fine control over double
buffering."

Double buffering will allow you to play sounds back-to-back,
continuously.  You can get the sounds directly from disk if that's what
your doubleback procedure does;  or, you can synthesize them, read them
from RAM, whatever.

The initial question (I think?!) was about playing some sounds
back-to-back.  Double-buffering will let you do that too (though, if you
have the RAM, and you don't mind BlockMove()ing it around, it's easier
to set up a SoundHeader with the combined data).
- --
 Jamie McCarthy      Internet: [e-mail]      AppleLink: j.mccarthy
 I tried to sleep my way to the top
 But my alarm clock always woke me right up

+++++++++++++++++++++++++++

From: [e-mail] (Joe Zobkiw)
Date: 6 Oct 92 12:37:04 GMT
Organization: The World Public Access UNIX, Brookline, MA

<< If you can get that 4-voice-harmony XCMD to work under 6.0.7, Lawrence,
a lot of people in the music-education biz would be very grateful.  :-)
>>

I wrote an XCMD called PlayChord about 3 years ago that is still available
on America Online and other places. The latest version on AOL is 1.5.1. It
uses the square-wave synth if memory serves and will play up to 4 notes
simultaneously using any of a number of waveforms (you can even create your
own, however, they are limited to 256 'steps' per waveform).

This was originally written under 6.0.5 with THINK Pascal at the time
and seems to even work fine on my Radius Rocket under 7.0.1! Now _that_
is truly portable code ;)

If anyone is interested I'd be glad totry and dig up the source although
I probably won't be proud of it anymore!

Check out the XCMD if any of you get a chance and drop me a line telling
me your thoughts.


- --
- -------------------------------------------------------------
joe zobkiw         [e-mail]        aol: aflzobkiw

macintosh.midi.synthesis.c.oop.asm.communications.graphics...

+++++++++++++++++++++++++++

From: [e-mail] (Daniel Norman Johnson)
Organization: Rensselaer Polytechnic Institute, Troy, NY.
Date: Tue, 6 Oct 1992 20:06:12 GMT

In article <[e-mail]>, [e-mail] (Jamie R. McCarthy) writes:
|> [e-mail] writes:
|> >Jamie R. McCarthy writes:
|> >> I was going to suggest using a custom double-buffering routine, but I've
|> >> never done it myself so I can't give advice.  I'd try that before
|> >> calling up MacDTS though.
|> >
|> >Waitaminute. I thot double buffering was a trick you could do
|> >to play direct from disk... if not, what is it?
|>
|> To quote IM VI 22-72:
[deletia- and he does, too]
|>
|> Double buffering will allow you to play sounds back-to-back,
|> continuously.  You can get the sounds directly from disk if that's what
|> your doubleback procedure does;  or, you can synthesize them, read them
|> from RAM, whatever.
|>
|> The initial question (I think?!) was about playing some sounds
|> back-to-back.  Double-buffering will let you do that too (though, if you
|> have the RAM, and you don't mind BlockMove()ing it around, it's easier
|> to set up a SoundHeader with the combined data).

Well, actually it had to do with playing sound asynchronously. They
are never played completely back to back (it doesnt play while
loading the next sound) and may be played with hours between the sounds.

- --
            - Dan Johnson
And God said "Jeeze, this is dull"... and it *WAS* dull. Genesis 0:0

These opinions have had all identifiying marks removed, and are untraceable.
You'll never know whose they are.

---------------------------

End of C.S.M.P. Digest
**********************