Software HDCD Decoding?

Toshito asks: "I found that I have several CD's with HDCD encoding. I understand that these CD's contain a 20 bits stream encoded in the 16 bits (the original signal is truncated at 15 bits). A standard CD player will play the 15 bits version, but you have to get a HDCD compatible player to access the 20 bits version. My question is: do you know of any way to decode this stream on a computer with software only? Is the decodind method secret and only available in chip (hardware) form?"

Comments

Re:Well...

[adolf]

I don't know about ogg, but MP3 is not at all tied to having things sampled at a specific bit-depth - it just doesn't matter to it whether it is 16, 20, or 24 bit - the format has sufficient dynamic range. I know of at least one free 24-bit MP3 decoder, but I've not run across anything for the encoding side just yet (and I haven't been looking, either).

'sides, HDCD essentially only adds 4 bits worth of dynamic range, for a total of 20, which isn't such a stretch for current consumer audio gear. The human ear is likely to be a greater limiting factor than the equipment.

And finally, there will never be any "exclusive content" on the HDCD layer, because there is no HDCD layer. The extra four bits are gleaned from unused space on a CD and interspersed with everything readable by a normal CD player. HDCD is an adjunct to a standard red book audio CD, not a replacement for it. Take away red book compatibility, and you not only remove 16 of HDCD's 20 bits, but eliminate compatibility with existing HDCD players (which are numerous indeed).

You're thinking of Sony's SACD, which can include multiple layers, and currently lacks ripping tools and PC-compatible hardware. I'm sure that Sony would love to convert the world to SACD and then stop adding a red book layer to their music as a cost-saving measure.

I doubt it will ever happen, however. Remember, this is the same company that brought you Beta, Minidisc, and Memory Stick. All of them are good, well-designed products, but lack of interoperability has always held them down, just as it will SACD.