Incorrect SF2 Import Result

Post your sforzando questions here

Moderators: eric_telemaque, davidv

gocha
Posts: 3
Joined: Sun Sep 17, 2017 11:26 pm
Contact:

Incorrect SF2 Import Result

Postby gocha » Mon Sep 18, 2017 8:31 am

Sforzando is one of my favorite VSTi. I usually use it as a SoundFont (*.sf2) player. However, I've found two problems on the SF2 import function.

I'm using Sforzando 1.916 on 64-bit Windows.

Issue 1: Offsets are always wrong

loop_point_issue.sf2

It seems like that Sforzando always exports 4 unwanted samples to the beginning of sf2_smpl.wav. Actually, it's the SF2 smpl chunk header copied wrong, which is 8 bytes long.

Workaround: Open sf2_smpl.wav and delete the first 4 samples, and save it.

Issue 2: Extra blank region (on the samples with multi-references?)

blank_region_issue.sf2

Sometimes, a converted SFZ file has a blank <region> tag. As a result, the preset will produce a broken sound, since the blank region will try playing the whole of sf2_smpl.wav.

I'm not sure about the exact condition to reproduce the issue, however, I guess it's caused by an instrument, whose samples are shared by multiple instruments.

Workaround: Just delete all blank regions! "<region>\n<region>\n" ==> "<region>\n"

I wish they were fixed in near future. Thank you for reading.

davidv
Site Admin
Posts: 1567
Joined: Tue Mar 02, 2004 7:23 pm
Contact:

Re: Incorrect SF2 Import Result

Postby davidv » Mon Sep 18, 2017 9:55 am

Hello

Our sf2 converter converts tons of sf2 out there and its the first report of such.
Looking at the SF2 file, they seem to be generated by polyphone, which oddly should support SFZ as well.

Looking into it...
David Viens,
Plogue Art et Technologie Inc. Montreal.
http://www.plogue.com

davidv
Site Admin
Posts: 1567
Joined: Tue Mar 02, 2004 7:23 pm
Contact:

Re: Incorrect SF2 Import Result

Postby davidv » Mon Sep 18, 2017 12:29 pm

Ok

loop_point_issue_sf2 : was my bad. Wow, a near 10 year old bug!

blank_region_issue_sf2: The file contains 5 zones with only 4 of them being present in the IGEN chunk.
I don't know if that's legal or not, or if our parsing of the structure is wrong, but in any case I added a band aid so that does not
create an empty <region>. I doubt I'll have the budget to investigate more as this is a freebie.

If you are on windows, please give this a spin?
https://s3.amazonaws.com/sforzando/WIN_ ... v1.929.exe

Cheers
David Viens,

Plogue Art et Technologie Inc. Montreal.

http://www.plogue.com

gocha
Posts: 3
Joined: Sun Sep 17, 2017 11:26 pm
Contact:

Re: Incorrect SF2 Import Result

Postby gocha » Mon Sep 18, 2017 6:41 pm

Did a quick test on the upcoming version. Apparently both bugs get fixed. Thank you for your quick support.

gocha
Posts: 3
Joined: Sun Sep 17, 2017 11:26 pm
Contact:

Re: Incorrect SF2 Import Result

Postby gocha » Mon Sep 18, 2017 8:35 pm

davidv wrote:blank_region_issue_sf2: The file contains 5 zones with only 4 of them being present in the IGEN chunk.


The first zone with no instrument/sampleID generator is a global zone. So, in blank_region_issue.sf2, there are 1 empty global zone + 4 zones.

I think it's still legal, there is no absolute proof though. I feel that Soundfont 2 specification is too complicated.

davidv
Site Admin
Posts: 1567
Joined: Tue Mar 02, 2004 7:23 pm
Contact:

Re: Incorrect SF2 Import Result

Postby davidv » Tue Sep 19, 2017 8:58 am

gocha wrote:I feel that Soundfont 2 specification is too complicated.


Yeah I didn't implement _everything_ really a pandora's box. or rats nest.

Thanks for the report!
I'll update the mac build and make a full release soon.
David Viens,

Plogue Art et Technologie Inc. Montreal.

http://www.plogue.com


Return to “sforzando”

Who is online

Users browsing this forum: No registered users and 1 guest