As a quick fix, would it work to use a temporary file for the data you
want to append? Something like this
wavwrite(wavdata_24,'temp')
f1=mopen('temp.wav'.,'rb')
wavdata_bytes=mget(n_bytes,'c',f1)
f2=mopen('main.wav','ab')
mput(wavdata_bytes(45:n_bytes),'c',f2)
Brgds
Jan
On 2019-12-18 5:37 AM, Federico Miyara wrote:
Stéphane,
Sorry for having explained myself so poorly. The problem with the
macros already available is that in order to save a wavfile in a
single operation, I need to have the whole signal loaded in a
variable. I'm not sure whether it is possible to handle a variable
with about 2 gigasamples (the maximum 16 bit mono file that Windows
allows --a total file size of 4 GB--). This would demand 16 GB just
for a single variable.
I'm pretty sure that problems would arise even with an audio variable
much smaller than that.
This is the reason why I need to be able to append new audio data to
an existing wave file, so that much less information is handled at a
time. Of course this requires to edit the header to update the file
size after the append, but this is quite easy.
The tough part is to save three byte numbers, since the existing mput
command supports 1, 2, 4 and 8 byte formats, but not the 3 byte used
for 24 bit audio. If there were a native macro or primitive capable of
formatting numbers as 3 byte, it would be helpful.
Thanks,
Federico Miyara
On 17/12/2019 18:37, Federico Miyara wrote:
Stéphane,
wavewrite also supports 3 bytes, but as I commented, I cannot save,
not evem generate huge files, so i must create them by successive
appending, so i needto be able to save 3 byte numbers directly.
Thanks anyway.
Regards,
Federico Miyara
On 17/12/2019 17:15, Stéphane Mottelet wrote:
Hello
I think it is supported in savewave and loadwave. There was a pb
with savewave but fixed by
https://codereview.scilab.org/#/c/19947/
in 6.0.2
S.
Le 17 déc. 2019 à 20:09, Federico Miyara <[email protected]>
a écrit :
Dear All,
While it is possible to create directly a wav file of reasonable
size from Scilab, if the size is very large, say, 1 Gb,we willmost
likely have memory problems. That's why I'm trying to program a
script allowing to append new audio data to an existing wav file.
It is simple to save 8 bit, 16 bit and 32 bit samples to a file.
However, 24 bit is also a popular format and Scilab doesn't seem to
support 3 byte integer format, either for variables and read/write
file operations.
Is there some way to save 3 byte integers other than creating a
specialized routine from scratch?
Regards,
Federico Miyara
_______________________________________________
users mailing list
[email protected]
https://antispam.utc.fr/proxy/1/c3RlcGhhbmUubW90dGVsZXRAdXRjLmZy/lists.scilab.org/mailman/listinfo/users
_______________________________________________
users mailing list
[email protected]
http://lists.scilab.org/mailman/listinfo/users
_______________________________________________
users mailing list
[email protected]
http://lists.scilab.org/mailman/listinfo/users
_______________________________________________
users mailing list
[email protected]
http://lists.scilab.org/mailman/listinfo/users
_______________________________________________
users mailing list
[email protected]
http://lists.scilab.org/mailman/listinfo/users
