View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0001241 | ardour | bugs | public | 2006-06-13 20:33 | 2020-04-19 20:12 |
| Reporter | naptastic | Assigned To | cth103 | ||
| Priority | normal | Severity | major | Reproducibility | have not tried |
| Status | closed | Resolution | fixed | ||
| Summary | 0001241: Resampling hot sources 44.1khz > 48khz causes distortion | ||||
| Description | I’m editing a trance remix of a major motion picture soundtrack, and the source track is quite loud, though it only hits 0dBFS once. I ripped it from CD in Windows and played with it in Cubase SX and it sounded great. When I imported it into Ardour, (and it was resampled to 48khz) some of the transients got distorted in a really vicious way. Screenshot at http://ranty.naptastic.com/artifacts.jpg You can see where the waveform seems to “wrap around” and it appears as a vertical line in the waveform. This is plainly audible and it sounds like a dropout, though it clearly isn’t. The top track is importation of the song after I went back into Windows and reduced the volume by 1%. The second track is the importation of the original CD audio track, which was ripped to WAV format in Windows (and it sounded fine there). I can provide source .WAV files if needed; any pop CD from this decade (Britney Spears et al) will probably generate the same trouble. | ||||
| Tags | No tags attached. | ||||
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Is this still an issue for you? |
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i don't think this is an ardour bug. what you are seeing is probably an inter-sample peak, which comes from the sinc interpolation. imagine two adjacent samples at full scale, with quieter samples around it. if you now do some upsampling, it's quite obvious that the new sample between those two full-scale ones will be over. so it's your source material that is faulty. what i don't understand is why this is showing up as distortion, since ardour is using floats. so there should be no wrap-around and no truncation to +/- 1.0 at this stage. that should probably be fixed in libsamplerate. are you using float as sample format, or int? can you provide a short excerpt of the sound file that shows this bug? i'd like to test it for myself and eventually throw it at eric via the LAD list... |
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closing due to lack of feedback - probably not an ardour issue in the first place. |
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The distortion comes from the fact that, on import, the clipping file is written to a new WAV file. If the new WAV is fixed-point, the problem occurs. |
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Believed fixed; see comments in related bug. |
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Issue has been closed automatically, by Trigger Close Plugin. Feel free to re-open with additional information if you think the issue is not resolved. |
| Date Modified | Username | Field | Change |
|---|---|---|---|
| 2006-06-13 20:33 | naptastic | New Issue | |
| 2006-06-13 20:33 | naptastic | => naptastic@comcast.net | |
| 2006-06-13 20:33 | naptastic | Name | => David Nielson |
| 2009-08-24 23:38 | cth103 | Note Added: 0006601 | |
| 2009-08-24 23:38 | cth103 | Status | new => feedback |
| 2009-08-26 12:06 | nettings | Note Added: 0006609 | |
| 2009-08-31 20:09 | nettings | cost | => 0.00 |
| 2009-08-31 20:09 | nettings | Note Added: 0006617 | |
| 2009-08-31 20:09 | nettings | Status | feedback => closed |
| 2009-08-31 20:09 | nettings | Resolution | open => unable to reproduce |
| 2010-04-08 01:25 | cth103 | Status | closed => feedback |
| 2010-04-08 01:25 | cth103 | Resolution | unable to reproduce => reopened |
| 2010-04-08 01:26 | cth103 | Status | feedback => confirmed |
| 2010-04-08 01:26 | cth103 | Relationship added | related to 0003061 |
| 2010-04-08 01:27 | cth103 | Note Added: 0007452 | |
| 2010-04-09 15:01 | cth103 | Note Added: 0007463 | |
| 2010-04-09 15:01 | cth103 | Status | confirmed => resolved |
| 2010-04-09 15:01 | cth103 | Resolution | reopened => fixed |
| 2010-04-09 15:01 | cth103 | Assigned To | => cth103 |
| 2020-04-19 20:12 | system | Note Added: 0021482 | |
| 2020-04-19 20:12 | system | Status | resolved => closed |
