cptkcmuscl Wrote: > Is there anything inherently wrong with putting the EAC ripped resultant > wav file in a flac wrapper then having the SB2 decode that? It SOUNDS > like a perfect duplicate of the original DTS audio file. Am I just more > willing to put up with a kludgy approach to playing my DTS discs than > others are? I plan on grabbing some AC3 snippets from movies I like and > perhaps from some DVD audio discs as well and see if I can do the same > thing.
For a DTS CD, that's exactly the right approach. The DTS bitstream is already in the right format, so EAC (or whatever) plus FLAC (or any other lossless codec) is the best solution. That IS a perfect duplicate of the DTS file on the disc, and I don't think it's hacky at all. But for a DVD, the approach must be different. For a start, EAC won't rip the audio data; it's stored in a different way to CDs. You need to use DVD-ripping software to extract the audio streams from a given chapter (say), and then you end up with a "raw" AC3 (Dolby Digital) or DTS file. Those files won't play as-is in your SqueezeBox, and simply wrapping them in a WAV won't work either. (My earlier attempt to convert to the DTS CD format also failed, due to differences in bitrates.) This week I've successfully played AC3 files on my SB2, by pre-processing them as follows: 1. Extract the AC3 file from a chapter on an audio DVD (or a film, or whatever). 2. Use a utility called 'ac3spdif' (I'm not sure this is still being developed, but I found a Windows binary after some Googling) to produce an AU file from the AC3 file. (There are probably other utilities to do similar transformations; we're trying to encapsulate the AC3 data in an IEC61937 stream.) 3. Use 'sox' to transform into a WAV file (I've used double extensions to remind myself not to play the files on my PC!): sox -t au myfile.ac3.au -t wav myfile.ac3.wav 4. Use 'flac' to reclaim some space and allow tagging. I've tried adding this process to the custom 'convert.conf', but there's a snag: 'sox' in the pipeline doesn't have access to the full AU file, so it can't calculate the length of the WAV file and therefore can't write the header. I plan to write my own encapsulation utility when I get the chance, writing a WAV file directly, and I think it should be possible to make a decent guess at the padded file size and write an estimate into the WAV file header. Now, DTS DVDs: this is essentially the same process as with AC3 files, but the encapsulation is slightly different. Instead of using 'ac3spdif' we must use something which I haven't found yet, but which I'll have a crack at writing myself in a few days. We can do essentially what 'ac3spdif' does, I think, but we just need to read the framing data differently. (That's not too hard, so it shouldn't be much of a change.) So, Larry: your DTS CDs can be ripped to FLAC and you'll get (through the SB2, but not the SB1 as I understand it) the DTS stream played perfectly. Dolby Digital DVDs can be ripped and added to the library with pre-processing (and in future without, although you'll lose the ability to tag them). DTS DVDs can be ripped in the future, both pre-processed and with on-the-fly conversion, assuming I can find the few hours I need to get some Python code written. :-) Cheers, Steve -- smst _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
