ogg dev - Nov 2018 - How to concatenate Ogg in the browser JS?

On 2018-11-15 11:01 a.m., Vitaly Zdanevich wrote:
> Maybe you know some existing code snippet or library for Javascript for
altering serial and crc?
I don't, sorry.
> Just now I compiled your quick script to wasm but the size is 28K, > I
think about simple correct solution for that case.
If you strip out the fprintf()s for progress and error reporting, it 
might get smaller. More so if you replace the open/memmap step with 
direct access to the blob as an array. But it's not very much code to 
just port the functions to pure js.

  -r

Thank you again for your help, now I am thinking about much simpler solution -
because all my Oggs comes from the the one source looks like I can alter serial
and crc32 at their hardcoded positions. Please see this screenshot
https://giphy.com/gifs/9AIe7ksYBwiYQoLVv9/fullscreen with serials 11111111 and
22222222- it will be correct approach? And can you please say me from what
region I need to calculate crc32? And also as we can see on the screenshot above
- changed two groups of numbers beside the serials - what is that? Thank you
very much for help.

16.11.2018, 04:01, "Ralph Giles" <giles at
thaumas.net>:
> On 2018-11-15 11:01 a.m., Vitaly Zdanevich wrote:
>>  Maybe you know some existing code snippet or library for Javascript
for altering serial and crc?
>
> I don't, sorry.
>
>>  Just now I compiled your quick script to wasm but the size is 28K,
> I think about simple correct solution for that case.
>
> If you strip out the fprintf()s for progress and error reporting, it
> might get smaller. More so if you replace the open/memmap step with
> direct access to the blob as an array. But it's not very much code to
> just port the functions to pure js.
>
>   -r

Please see the documentation: https://xiph.org/ogg/doc/framing.html

I would encourage you to use random serial numbers, as intended, also, 
as any downstream consumers of your files will face limitations similar 
to the ones you are facing if they want to do anything more with them.

But before you go too far down the route of changing the serial numbers, 
can you tell us what software is producing Oggs with a hard-coded serial 
number to begin with?

Vitaly Zdanevich wrote:
> Thank you again for your help, now I am thinking about much simpler
solution - because all my Oggs comes from the the one source looks like I can
alter serial and crc32 at their hardcoded positions. Please see this screenshot
https://giphy.com/gifs/9AIe7ksYBwiYQoLVv9/fullscreen with serials 11111111 and
22222222- it will be correct approach? And can you please say me from what
region I need to calculate crc32? And also as we can see on the screenshot above
- changed two groups of numbers beside the serials - what is that? Thank you
very much for help.
> 
> 16.11.2018, 04:01, "Ralph Giles" <giles at thaumas.net>:
>> On 2018-11-15 11:01 a.m., Vitaly Zdanevich wrote:
>>>   Maybe you know some existing code snippet or library for
Javascript for altering serial and crc?
>>
>> I don't, sorry.
>>
>>>   Just now I compiled your quick script to wasm but the size is
28K, > I think about simple correct solution for that case.
>>
>> If you strip out the fprintf()s for progress and error reporting, it
>> might get smaller. More so if you replace the open/memmap step with
>> direct access to the blob as an array. But it's not very much code
to
>> just port the functions to pure js.
>>
>>    -r
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