DimeFAQ:Circumstances Allowing Certain Lossy Audio Seeds

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In general, lossily compressed audio material is not permitted on DIME. There is a limited set of relaxations of that policy, as listed below.

Regardless of any provision on this page, the torrent must not be in violation of DIME's general policies for permitted torrents, of DIME's list of prohibited bands and artists, nor of DIME's list of prohibited venues and events.

Furthermore, the material must not have been available to collectors at a higher bit rate, and it must not be expected to become available to collectors at a higher bit rate. (Captures by two tapers’ microphones at the show, or by a taper's microphone and the soundboard, are treated as different material; two listeners’ recordings of the same broadcast content are not.)

The ensuing is a complete and exhaustive list of circumstances where DIME might allow a torrent of lossy audio files, with their respective specifications. If you have lossy audio that does not meet any of these listed exceptions, it is not permissible in a DIME torrent. However, this listing may change at any time, so check back here whenever you are considering uploading lossy audio onto DIME.


Contents


Regarding digital stream sources

Note: This section pertains to captures of streamed digital audio sources such as satellite broadcasts, webcasts, and digital television dish reception. See elsewhere on this page for policies covering material already captured or circulating as lossy digital files or the audio content of a digital video file or of a video on DVD.

Nearly all digital broadcasts and webcasts carry lossily compressed content. For some examples, broadcasts bearing acronyms such as DVB, DAB, and ADR or carried on networks like Sky Digital and Freeview are lossily compressed digital streams. Despite being lossy, they may be shared on DIME, provided that

  1. No higher-bitrate digicast source is known to be at the trading community's disposal;
  2. The description on the torrent's page and the internal info file of the torrent state both the compression format and the bit rate of the broadcast stream;
    and
  3. either ...
    Preferably, the lossily compressed material is shared in its original compressed format, even if that prevents dividing it into tracks;
    or
    If the stream was transmitted at a bit rate of 192 kb/s or greater (for spoken [but music-related] content, 64 kb/s or greater), it may be shared in a conversion to a lossless compression format.

This provision is a special relaxation of DIME's standard losslessness requirement. If the bit rate and the codec are not stated, or if the torrent's information does not acknowledge its descent from a digital stream, then it does not qualify for this relaxation, and if the material proves lossy, the torrent may be banned for lossiness or lack of information or both.

NOTE ON TOTAL RECORDER AND SIMILAR SOFTWARE: Webstream sources recorded as .wav with this kind of software are NOT allowed, unless the bitrate of the webstream was 192 kb/s or greater, and the bitrate and format of the original source is stated in the torrent's description. Programs like Total Recorder do not record the source in an unchanged form but convert it.

An analog broadcast and a digicast of the same content will, in general, be deemed acceptable alternative sources, and a torrent of each may run on DIME at the same time if there are no other violations in them. If you are posting a torrent derived from an digital broadcast when one from an analog broadcast or an audience capture of the same performance is already on DIME, see the FAQ item on multiple torrents of the same performance and its subsections about alternative versions and the required contrast clause.

Here are links for finding out the stream characteristics of some sources:

For DIME policy regarding lossless digital-stream sources, see this item in our FAQ.

#lossystreams

Regarding digital cable sources

At this writing on July 9, 2007, we are reconsidering our policies on digital cable sources. They heretofore have been more liberal than those for other digital streams (see above), but that may change. For now, audio from digital cable will be acceptable only if it meets the regular digital stream provisions.

#digitalcable

Regarding MiniDisc recordings

ATRAC encoding on MiniDiscs is lossy, though generally considered to be less damaging than MP3 encoding. However, it is not possible to write actual ATRAC data as files that can be shared via BitTorrent, so MiniDisc tracks must be dubbed to PCM for torrenting (and then, per DIME policy, compressed without further loss and divided, unless inapplicable, into tracks). DIME will permit such material, provided that it meets all other applicable requirements, when the torrent's lineage information provided by the uploader documents that ...

  • The original capture from a microphone at the performance was direct to an MD recorder, in either MDSP or MDLP (any better source would have to be from a different capture and therefore the ATRACked version could run as an alternative),
    or
  • An analog source for audio (for example, an FM or TV signal, or an audiocassette, a videotape's audio, or a vinyl platter) was digitized by being dubbed to MD in MDSP — MDLP is unacceptable for this — and no source that is less lossy is available on DIME;

but

  • An encoding into ATRAC that is preceded anywhere in the lineage by a digitally stored generation disqualifies the material from being shared via DIME.

The foregoing provision applies only to ATRAC encodings. PCM recordings captured in Hi-MD mode on Hi-MD equipment are lossless and should be shared in a lossless compression format and, unless inapplicable, divided into tracks.

Lossy audio material that lacks the required lineage information will not qualify for this variance, and will be treated like any other lossy audio.

#minidisc or #atrac

Regarding DAT recordings at 32000 samples per second

These are subject to the same rules as MiniDisc recordings in MDSP in the preceding section. If they are shared still sampled at 32 kHz, that must be stated in the description so that downloaders will know that the files are not CD-DA-ready. If the files in the torrent have been resampled to 44100 kHz, the 32-kHz ancestry should still be disclosed in the lineage if known.

DAT recordings at 44100 or 48000 samples per second are considered lossless and do not need to meet the rules on this page. They should be shared in a lossless compression format and, unless inapplicable, divided into tracks.

#dat32khz

Regarding an original capture as files in a lossy codec

If the original microphone capture at the actual event was made directly to a recording device that encoded the signal in one or more lossy files as it wrote, DIME will permit a torrent of the files as recorded in their original codec, even if that means not splitting the material into tracks. A conversion from the original lossy capture's files to another codec or filetype or a reencoding of any sort will not qualify for this relaxation and is not permitted on DIME.

See DimeWiki article Moderator Override for instructions on how to submit such a torrent. The torrent's description and its internal info file must state the bit rate and codec of these files from the original capture.

Note: MiniDisc tracks and DAT tracks are not files and are covered in the MiniDisc and DAT sections of this page respectively.

#directencoding

Regarding audio extracted from a video

Nearly all digital video has a lossy audio layer. If the best or only source known for the material is a video with lossily compressed sound, and there is no other violation in it, DIME will accept a torrent of such audio only if it is an unconverted demuxing still in the native filetype for the original audio codec of the video, even if that prevents splitting the material into tracks. A conversion or dub to another filetype or codec is not permitted.

The torrent's description and its internal info file should state the bit rate and codec of the audio component of the digital video source.

If a video DVD is explicitly known to have lossless LPCM audio, and you wish to torrent the audio from it, and there are no violations of other DIME policies in it, then the audio must be shared in a lossless compression codec and, unless inapplicable for that content, it must be divided into tracks.

#extracted or #demuxed

Regarding free lossy distributions from an official source (not as streams)

Sometimes the only recording of a given performance available to collectors is a free lossy download formerly available from the artist's or the label's site, or a CD-Audio disc of lossy ancestry that the artist or the label or a radio station distributed for free, and no lossless or less lossy recording is known to have been in the possession of any collector. In those circumstances we can relax our losslessness rule for it as detailed below.

Caution #1: if there was a charge for it, or if another distribution of the same performance was legitimately sold for a charge, it is forbidden as official content.

Caution #2: if the files are still available to download from the artist's or the label's site, users can get the content there. A torrent on DIME is unnecessary.

If the free distribution came as files (such as a download), the files are not acceptable if they have been converted to another codec or otherwise reencoded. See the article Moderator Override in this wiki for instructions on how to submit a torrent of the original files.

If it came as a stream, see above.

If the free distribution came as a CD-Audio disc, then, much like an MDLP recording, the tracks should be ripped and compressed to a codec like FLAC or SHN without further loss. The description and the internal information file must both explain the lineage, or the torrent will be subject to ban for lossiness.

#freelossycopies
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