peterjwhite;196945 Wrote: > Hi Eric, thanks for your reply. The problem is that spdifconvert.py is > doing the transcoding.
What Eric means is that after converting it to a WAV, something in the SlimServer -> SqueezeBox2 (or 3) pipeline might be performing additional transcoding that you didn't expect. One source of this is the bandwidth limiting option in SlimServer, which re-encodes to MP3; another is the use of anything other than 100% volume on the digital out. Please check the second post of this thread, containing a sub-section titled "Configuring SlimServer". > All I want it to do is add the 36 byte (or however many bytes it is) > wave header to the raw DTS data file, but instead it's doing frame by > frame analysis of the data and playing around with it (e.g. doubling > the file size from 15MB to 30MB!). It MUST convert each frame if the DTS has come from a DVD. Just adding the WAV header is not enough -- the format of the data in the will not be correct if it's exactly the same as the DTS from the DVD. In order to trick the SB2 and the amp into playing this data, we must encapsulate it in an IEC61937 stream, and that means taking each frame and padding it. > I'm playing with the python code now to see if I can add my own "raw" > option in addition to the supplied ac3 and dts options such that it > will add a wave header to raw files but not modify the data. You are of course free to modify the code as you wish (and if you have success I'd be grateful if you post here again with information) but I honestly believe it won't help. If you've ripped the file from a DVD, and the utility has recognised it as something it can work on, then the correct thing to do is to pad the frames as it's doing. > BTW For reference I use the free DTS .WAV samples from Diatonis to check > that the receiver is receiving and playing DTS data streams ok. The files on the Diatonis website use a slightly different form of DTS (a special 14-bit format suitable for packing into WAV in such a way that a DTS-CD can be created, IIRC). They've already been converted to WAV. It's possible that they use less bandwidth than the files you've ripped from DVD, so it's worth checking the SlimServer configuration anyway. peterjwhite;196749 Wrote: > Hi, I have successfully ripped .dts files from a DVD-Audio but I'm > having no success getting spdifconvert.py to create usable .wav files. > > Firstly, I've verified that the .dts files are ok by playing them with > dtsdec.exe. Note that the filesize for my test track is about 15MB and > the output below from dtsdec shows 15318 frames: > C:\>dtsdec dvd_ae.dts > dtsdec-0.7.4-cvs - by Gildas Bazin <[EMAIL PROTECTED]> > based on the a52dec code from Michel Lespinasse <[EMAIL PROTECTED]> and > Aaron Holtzman > Stream with high frequencies VQ coding > 15318 frames decoded in 163.23 seconds (93.84 fps) > When I run it through spdifconvert the result is correctly 15318 > frames, but over wireless to my dts decoder it's not recognised as DTS > and plays as noise. Note that with the default frame-size=2048 the file > size is double of the original, i.e. it has become 30MB. I tried using > --frame-size=1006 and while the file was back to 15MB it still played > noise. The verbose output is below. > C:\>spdifconvert.py -v dvd_ae.dts > Reading input from file dvd_ae.dts > Writing output to file dvd_ae.dts.wav > Detected stream type: dts > DTS frame data: FSIZE 1005 > DTS frame data: NBLKS 15 > DTS frame data: SFREQ 13; sample rate is 48000 > Padding output file to frame size 2048 > DTS length: 15409908; frame length: 1006 > Guessing 15318 DTS frames, WAV length 31371264 bytes > WAV header does not need fixing (good estimate!) > Completed transformation. Took 0m02s. > Any suggestions? How long is the track supposed to be? Is it about 2:43? If so, that WAV size seems correct. Is it supposed to be twice that length? If so, it seems wrong! You could try a frame size of 1024 instead of 2048, but I don't know if it will work. If it does, I'd love to hear about it! Is it possible to try streaming over a wired connection, in case it's a problem with the wireless? And are you converting to FLAC or streaming the WAV? The frame size is chosen by multiplying the number of blocks (NBLKS+1) by 32 (the number of samples in a DTS frame), then multiplying that by the sample size (2 bytes) and the number of output channels (2 -- because we're packing into something that looks like a stereo WAV. The number of channels in the source DTS file is not relevant here AFAIK). The figures you've posted look okay to me. (The fact that FSIZE is smaller indicates, I think, a half-bitrate DTS file.) It's generally expected that the output file will be larger than the input file: the WAV will be the right size for 16-bit stereo PCM data, which is what the DTS is pretending to be for streaming to the SB2. Please feel free to send me a private message if you'd like me to take a look at the file -- I'll give you an email address that can accept it. I'd be happy to take a look at it when I have a minute (hopefully some time today!). -- smst ------------------------------------------------------------------------ smst's Profile: http://forums.slimdevices.com/member.php?userid=752 View this thread: http://forums.slimdevices.com/showthread.php?t=19260 _______________________________________________ ripping mailing list [email protected] http://lists.slimdevices.com/lists/listinfo/ripping
