Re: [MP3 ENCODER] Quantized values 8191?
Hi Mark, I'm pretty sure it is okay as is. Values greater than 8191 would always be encoded with "linbits", meaning the number is written directly into the bitstream after an escape code. linbits allows up to 13 digits, which would give an upper bound of 8191. But with mp3/linbits, 15 is subtracted before the number is written to the bitstream. Thus the actual maximum is 8206. (numbers 15 are encoded with huffman codes) I understand how values up to 8206 can be encoded; my question is whether it should be considered legal to encode values greater than 8191, since a decoder relying on the statement in ISO/IEC 11172-3 that "[t]he maximum absolute value in this [big_values] range is constrained to 8191" might be tempted to allocate a requantization lookup table with only 8192 entries. Such was the case in my own implementation until I discovered LAME could (albeit rarely) create bitstreams with encoded values 8191. It wouldn't be the only ambiguous statement in the standard, but in context it does appear pretty clear. The informative statements in C.1.5.4.4.2 are less clear but, at face value, could also support the conclusion that the maximum absolute value should be constrained by linbits alone, and not 2^linbits + 15. At least one argument I can think of in favor of the limit, other than the assertion in the standard, is to help prevent creating false sync words. It can also serve as minimal error detection. More thoughts? -- Rob Leslie [EMAIL PROTECTED] -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
Re: [MP3 ENCODER] Encoders genealogy
Xing evolved from tompg, which I think is also a direct descendent of the ISO code. The tompg source code is out there, so you could check. It's the second time that someone mentions the tompg sources as beeing available. But does anyone knows where to find them? Regards, -- Gabriel Bouvigne - France [EMAIL PROTECTED] icq: 12138873 MP3' Tech: www.mp3-tech.org -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
[MP3 ENCODER] About Vorbis
Osamu Shigematsu wrote: Here in Japan, we may need patent license even f ree encoder. ($15000 every year) By the way, I found following patent free sound format about 2 days ago. http://www.xiph.org/ogg/vorbis/ What's this? If this was really patent free and open source (GPLd/LGPLd), I hope I can port it to Mac. Also visit http://www.vorbis.com/ , they released version 1.0beta yesterday ( tue, 20-jun-2000 ) I read in an article at http://www.inside.com/story/Story_Cached/0,2770,6015,00.html --start quote--- The LAME project, which makes MP3 encoders for Linux, was unable to afford a Fraunhofer license and had to pull executable files from its Web page. LAME is releasing a Vorbis encoder on Tuesday and, Montgomery says, ''basically switching out of MP3 altogether.'' --end quote--- The mentioned tuesday is Jun 20,2000. Montgomery is the key man of Vorbis. So Mark, what about some clarification ? David Balazic -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
[MP3 ENCODER] Re: legality (was: C++ LAME?)
David Balazic wrote: Yeah , but what if someone in Germany wants to use it ? He can not , unless he breaks the law. Isn't that the same with LAME and even an MP3 decoder? All you people using LAME in the US and Germany are currently breaking the law :-). Erik If you only release/download source code, there is no problem. Any user as the right to compile source code for his own use, as long as he doesn't release any binaries. So in the case of Lame, the Lame website, Mark, and all the people who download source code and compile themselves are legally ok. Those infringing the law are Dmitry, myself, and all the people downloading the binaries from our websites. Regards, -- Gabriel Bouvigne - France [EMAIL PROTECTED] icq: 12138873 MP3' Tech: www.mp3-tech.org -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
Re: [MP3 ENCODER] About Vorbis
Also visit http://www.vorbis.com/ , they released version 1.0beta yesterday ( tue, 20-jun-2000 ) I read in an article at http://www.inside.com/story/Story_Cached/0,2770,6015,00.html --start quote--- The LAME project, which makes MP3 encoders for Linux, was unable to afford a Fraunhofer license and had to pull executable files from its Web page. LAME is releasing a Vorbis encoder on Tuesday and, Montgomery says, ''basically switching out of MP3 altogether.'' --end quote--- The mentioned tuesday is Jun 20,2000. Montgomery is the key man of Vorbis. So Mark, what about some clarification ? David Balazic -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ ) The CVS version of LAME can decode and encode .ogg files (using libvorbis). But LAME will not be dropping MP3 nor making Vorbis the default. Vorbis now produces streams which average about 128kbs. But in my own blind tests of a few samples, I rated the Vorbis stream as worse quality than mp3 every time. But Vorbis is still alpha, and is already clearly higher quality than the ISO mp3 code (and thus higher quality than LAME was about 1.5 years ago). So with more work it might match or even exceed MP3. When Vorbis adds support for higher bitrates, it will probably be very hard to tell the difference between Vorbis and mp3 at around 200kbs. I like this quote: --start quote--- According to Brandenburg, the ISO asked Fraunhofer to develop sample encoding and decoding software as a tool for industry to learn how to use MP3. The source code -- the underlying instructions -- for these programs was carelessly placed on an insecure university server, where it was later obtained by a hacker in Amsterdam known as SoloH. (Brandenburg says the download was not authorized but also not illegal.) Using SoloH's source code, coders across Europe and the United States wrote and gave away MP3 software of their own, creating -- without the participation of the music industry -- the base for today's explosion of online music. --end quote--- -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
[MP3 ENCODER] square wave and vbrtest.wav problem
The vbrtest.wav problem can be reproduced with a simple square wave. http://www.geocities.co.jp/Technopolis/9674/lametest/index.html -- Naoki Shibata e-mail: [EMAIL PROTECTED] -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
Re: [MP3 ENCODER] About Vorbis
I like this quote: --start quote--- According to Brandenburg, the ISO asked Fraunhofer to develop sample encoding and decoding software as a tool for industry to learn how to use MP3. The source code -- the underlying instructions -- for these programs was carelessly placed on an insecure university server, where it was later obtained by a hacker in Amsterdam known as SoloH. (Brandenburg says the download was not authorized but also not illegal.) Using SoloH's source code, coders across Europe and the United States wrote and gave away MP3 software of their own, creating -- without the participation of the music industry -- the base for today's explosion of online music. --end quote--- Wow, is THIS how we all got the ISO MP3 code!? If SoloH didn't hack-in, wouldn't there have been LAME??? -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
[MP3 ENCODER] Wither MP3 ?
I saw a disturbing report tonight on the Register http://www.theregister.co.uk/content/1/11499.html which indicates hardware manufacturers may be set to dump MP3 in favour of AAC. Hard to estimate what kind of a threat S3's adoption of AAC will pose for MP3 - but the quality/filesize ratio is bound to have an effect on people who use portable devices. Has anyone seen any info on how AAC encoders are to be licensed for individual/private use ? I imagine the format will be tightly controlled. AOL's purchase of Nullsoft seemed a good omen for MP3 but in view of the proposed merger with Time Warner this might now cause some embarrassment. As I use MP3 for just making my favourite CD tracks available on my PC I'm not personally concerned - the current Lame exe at 256 cbr is probably overkill for my old ears and hard drives are cheap :) StillI'd be interested in how others here view the threat from Dolby. Eric -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
Re: [MP3 ENCODER] Wither MP3 ?
Eric.Howgate wrote: I saw a disturbing report tonight on the Register http://www.theregister.co.uk/content/1/11499.html which indicates hardware manufacturers may be set to dump MP3 in favour of AAC. Hard to estimate what kind of a threat S3's adoption of AAC will pose for MP3 - but the quality/filesize ratio is bound to have an effect on people who use portable devices. Has anyone seen any info on how AAC encoders are to be licensed for individual/private use ? I imagine the format will be tightly controlled. There is an open source encoder/decoder. I found out about it by following a link about an AAC plugin for XMMS on the XMMS project page. I eventually ended up here: http://faac.sourceforge.net/ Erik -- +-+ Erik de Castro Lopo [EMAIL PROTECTED] +-+ " ... new TV ad for Microsoft's Internet Explorer e-mail program which uses the musical theme of the "Confutatis Maledictis" from Mozart's Requiem. "Where do you want to go today?" is the cheery line on the screen, while the chorus sings "Confutatis maledictis, flammis acribus addictis,". This translates to "The damned and accursed are convicted to the flames of hell." -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
Re: [MP3 ENCODER] About Vorbis
Mark Taylor wrote: I like this quote: --start quote--- According to Brandenburg, the ISO asked Fraunhofer to develop sample encoding and decoding software as a tool for industry to learn how to use MP3. The source code -- the underlying instructions -- for these programs was carelessly placed on an insecure university server, where it was later obtained by a hacker in Amsterdam known as SoloH. (Brandenburg says the download was not authorized but also not illegal.) Using SoloH's source code, coders across Europe and the United States wrote and gave away MP3 software of their own, creating -- without the participation of the music industry -- the base for today's explosion of online music. --end quote--- I thought the ISO source code was freely available from Fraunhofer's ftp site well before SoloH released his encoder, but then it was a few years ago now and time maybe playing tricks. Ross. -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
