Stream checksum

burning shadow · 06 December 2005, 11:51 am

Most quality ripping standards require 'MD5 locking' of files. Personally I think it is very bad idea because modifing tags, calculating RG values, etc, modifies file checksum. Then there is no use of it at all. My idea is to add stream checksum feature which would be written to MPC header and couldn't be modified. This would give a possibility to implement fast checking for broken streams (instead of checking each frame) and remove the need of useless MD5 file locking.

Shy · 06 December 2005, 06:22 pm

Changing the header in that way will break compatibility. However, someone could code a little tool that writes the stream's MD5 checksum to an APEv2 tag, and compares the stream's checksum to the checksum in the tag.

burning shadow · 07 December 2005, 08:42 am

Good idea.

I think it should be included in codec package though. And it would be perfectly if it would be performed by codec itself during encoding process.

burning shadow · 06 October 2007, 11:40 pm

By the way, since new stream version is on it's way to release, maybe my wish could be reviewed?

r2d · 08 October 2007, 12:35 pm

Quote:

Originally Posted by burning shadow

By the way, since new stream version is on it's way to release, maybe my wish could be reviewed?

As you can see in the sv8 spec (http://trac.musepack.net/trac/wiki/S...SecurityPacket) no decision has been made on this issue. If a security feature is implemented, I prefer error correcting codes.

xmixahlx · 08 October 2007, 05:05 pm

i think an md5 packet of the audio stream is a good idea... hell, perhaps you could have both md5 and error codes...

an md5 and par2 with every musepack file

06 December 2005, 11:51 am	#1
burning shadow Member Join Date: Dec 2005 Location: St.Petersburg, Russia Posts: 4	Stream checksum Most quality ripping standards require 'MD5 locking' of files. Personally I think it is very bad idea because modifing tags, calculating RG values, etc, modifies file checksum. Then there is no use of it at all. My idea is to add stream checksum feature which would be written to MPC header and couldn't be modified. This would give a possibility to implement fast checking for broken streams (instead of checking each frame) and remove the need of useless MD5 file locking.

08 October 2007, 05:05 pm	#6
xmixahlx Musepack developer Join Date: Nov 2004 Location: seattle, washington usa Posts: 111	i think an md5 packet of the audio stream is a good idea... hell, perhaps you could have both md5 and error codes... an md5 and par2 with every musepack file __________________ -xmixahlx, the one they call "mike" http://xmixahlx.com -\|- http://rarewares.org

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06 December 2005, 06:22 pm	#2
Shy Admin Join Date: Jul 2004 Posts: 370	Changing the header in that way will break compatibility. However, someone could code a little tool that writes the stream's MD5 checksum to an APEv2 tag, and compares the stream's checksum to the checksum in the tag.

07 December 2005, 08:42 am	#3
burning shadow Member Join Date: Dec 2005 Location: St.Petersburg, Russia Posts: 4	Good idea. I think it should be included in codec package though. And it would be perfectly if it would be performed by codec itself during encoding process.

06 October 2007, 11:40 pm	#4
burning shadow Member Join Date: Dec 2005 Location: St.Petersburg, Russia Posts: 4	By the way, since new stream version is on it's way to release, maybe my wish could be reviewed?