I use Gmail and it doesn't allow .dll or .exe attachments. Could you post a download link here?

Recently an error appeared when calling BASS_StreamFree on a channel which is a source channel for a mixer:

Access violation at address 10503DAB in module 'bassmix.dll'. Read of address 13E42030.
10503dab +029 bassmix.dll                             BASS_Mixer_ChannelRemove
1101a590 +01d bass.dll                                BASS_StreamFree

and another one, slightly different, location in bass.dll is the same:

Access violation at address 7C9208D3 in module 'ntdll.dll'. Read of address 03334441.
7c9208d3 +9a6 ntdll.dll                             RtlFreeHeap
77bfc2d8 +0bd msvcrt.dll                            free
1101a590 +01d bass.dll                              BASS_StreamFree

bassmix.dll version is 2.4.7.0, bass.dll is 2.4.9.3

What could it be?

This is pretty reproducable (happens every couple of hours or so) - I think I could come up with more information soon. Would the dump file generated via Process Explorer be helpful? (and if so, should I use Minidump or Full dump?)

You'll need to use bassenc addon to do that.

Yes, it works

Thanks!

[The crash doesn't appear if either:]

I narrowed the problem down to a pretty little program, here's the code:

var
  C: HCHANNEL;
  buf: array of Byte;
  D: String;
begin
  D := ExtractFilePath(ParamStr(0)); //get the executable path
  BASS_Init(0, 44100, 0, Handle, nil);
  BASS_PluginLoad(PChar(D + 'bass_aac.dll'), BASS_UNICODE); //<-- without this line there's no crash...
  C := BASS_StreamCreateFile(False, PChar(D + 'Billy Ocean - Loverboy.m4a'), 0, 0, BASS_STREAM_DECODE or BASS_SAMPLE_FLOAT or BASS_UNICODE);
  SetLength(buf, 10000000);
  BASS_ChannelSetPosition(C, 0, 0); //<-- without this line there's no crash...
  BASS_ChannelGetData(C, @buf[0], 10000000);
end;

The crash doesn't appear if either:

1) BASS_PluginLoad line is commented out and the channel is created without using plugins. This pops up a question: how does BASS opens an m4a file without plugins? (the BASS_ChannelInfo returns "0" in the plugin field to confirm it). When the file is handled by BASS, there's no crash and file plays fine. Probably a good solution will be to give BASS a priority when creating streams, eg. try plugins only if BASS was unable to open the file.

2) BASS_ChannelSetPosition line is commented out. It doesn't crash if position is set to 100000 or more, but crashes for values under 10000 (approx.).

Here's the program and test mp4 file: http://www.djsoft.net/crash.rar

Hmm... the BASS_Encode_SetNotify function is not working with the encoders created via BASS_WMA_EncodeOpenPublish The error code is 37, which is "The encoder was not created with BASS_WMA_EncodeOpenNetwork".

I wanted to use it to count listeners, but it didn't work out...

It seems like I found a solution (sort of)
If calling to BASS_WMA_EncodeWrite fails, the program decides that connection is dead. Not sure if it's a correct solution, but it's better than nothing.

If "mix" is a decoding channel, then ChannelGetData/GetLevel calls will steal data from playback, that's why playback becomes "faster".

I'm using BASS_WMA_EncodeOpenPublish to stream data tothe Windows Media Server, this part works fine.
The question is: how to detect if connection was closed so program will perform reconnect? Is there a function like BASS_Encode_SetNotify exist for WMA encoders I don't know about?

Thanks for help, saga!

@Björn Petersen have you tried loading Waves (waves.com) plugins with bass_vst? It seems that those plugins cannot be used by bassvst. I'll check and give some details tomorrow.

At some point Waves used "Shell" plugins, which is a special kind of VST plugin. Not sure if they are still doing this (it sounds like that is the case), but if yes, you cannot use them without extra effort in the VST handling part (i.e. in BASS VST).

Could you please give any details on what efforts should be done?
There's only one DLL for all plugins, so it looks like "Shell"...

My program already using CPU cores - decoding on 2 threads. Probably I should do 4 threads because many people already have 4+ core cpu's so at least they will have more speed

Maybe it is possible to somehow perform a low-quality decode of MP3?

Caching is not a good solution in my case, people add new tracks to the library and want to edit how they played - that's when the waveform is displayed, eg. they anyway need to wait those 2 seconds... And probably this will be the only time they need this waveform.

That sounds like it may be the same issue that another user encountered recently. The failed response from the gateway is being cached, and BASS keeps receiving that when it retries. Here's the latest build that should bypass any caching (adds a "Cache-control: no-cache" request header)...

   www.un4seen.com/stuff/bass.dll

Please give that a try and see if the problem still happens.

Wow! That's the problem I had too, but I thought it's my program fault Thanks for the "stuff" version which solved this!

@Björn Petersen have you tried loading Waves (waves.com) plugins with bass_vst? It seems that those plugins cannot be used by bassvst. I'll check and give some details tomorrow.

@drugoimir - yes caching a waveform is not a question... The question is how to decode file without consuming time? Using cache is possible, but it will still take time for first time display.

Currently it takes couple of seconds to decode 5 minute MP3, but users complaing that it's too much wait and they want instant waveform display. =)

Decoder will always return the same data, regardless of the buffer size

Of course, but speed can be different. Eg if you do millions of calls to _GetData with 1 byte buffer, it will take some time to decode

BASS_ChannelGetData for a whole file at once still takes couple of seconds.

The drawing is not a problem, I use GDI+ and it's really fast. Also the code which reads a track is in another thread, and I measure the time it takes to decode the file.

Decoding a file is a problem... It takes too long (it's not instant )

I want to display a waveform of a file. To display it I decode the whole file using BASS_ChannelGetData and then draw it using the PCM values.
All this works, but takes about 3-5 seconds to display (for the average mp3 file).

I tried to decode a little part, then change position ahead, decode another small part and so on... But the waveform looks a little bit different if I do it this way

Is there a way to speed up the decoding process somehow? Perhaps trade quality for speed?

You should use the BASSmix addon if you want to mix 2 files together.

I don't think BASS will help you much with sending bytes to USB port.

What do you mean by "playing music"? You can use the loopback device to capture the music playing on the computer and get PCM data (bytes) of it.

Maybe you're using low sampling frequency, eg 22050Hz?