2009/5/27 <j...@rice.edu>: > Hello, > > I am Jose Garcia, an electrical engineering student at Rice University > in Houston, TX. I am doing some research which involves decoding and > encoding MP3 files. I learned about the LAME encoder recently, and it > seems like a great tool. However, I have some questions about the > inner works of LAME which I could not resolve simply online. I would > greatly appreciate answers to the following questions. > > 1. What are the basic step by step functions that LAME uses for > encoding WAV files into MP3's? For example, first sampling, then > quantization, application of filters, etc. > > 2. Since MP3 uses forward adaptive bit allocation, encoders quantize > and perform all calculations, and the bit allocations are encoded and > sent to the decoder. How exactly does the ?encoding? actually happen > in LAME? For example, do you use some sort of Huffman coding? If it is > not a well known variation, what are the properties and basic formula? > > 3. What transform does LAME use? (such as MDCT) > > 4. What digital filters does LAME use, and for what purpose? > (low-pass, band-pass, etc.) > > 5. How is subband coding used in LAME? > > 6. How does GPSYCHO use psycho-acoustics? For example, does it have a > set table of values which it compares audio to? If so, where can I > find information about the table of values used? > > 7. Is the high-pass filter for GPSYCHO implemented yet, or is it still > just a low-pass filter? If a high-pass filter is implemented, what > version of LAME includes the additional filter? > > 8. What is the basic formula for the GPSYCHO filters? > > I apologize if this is the wrong email to send these questions. If so, > I would appreciate it if you forwarded this email to anyone who can > answer the questions or if I am sent an alternate email address. > > Thanks, > > Jose > > _______________________________________________ > mp3encoder mailing list > mp3encoder@minnie.tuhs.org > https://minnie.tuhs.org/mailman/listinfo/mp3encoder >
If everything else fails, you can always try downloading LAME's source code from here: http://sourceforge.net/project/showfiles.php?group_id=290&package_id=309&release_id=628063 and giving it to an experienced programmer to study it a bit. If you find someone who is willing to do that for you. _______________________________________________ mp3encoder mailing list mp3encoder@minnie.tuhs.org https://minnie.tuhs.org/mailman/listinfo/mp3encoder
