Core descriptors
Version 64 (Jan Schacher, 08/03/2009 11:46 am)
| 1 | 61 | Jan Schacher | h1. Core descriptors |
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| 2 | 1 | ||
| 3 | 1 | The following descriptors are currently proposed as core descriptors. |
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| 4 | 35 | Jan Schacher | Core descriptors should be understood by *_every SpatDIF compliant renderer_*. |
| 5 | 1 | ||
| 6 | 53 | Jan Schacher | |
| 7 | 61 | Jan Schacher | h2. Entities |
| 8 | 53 | Jan Schacher | |
| 9 | 54 | Jan Schacher | The core descriptors can be assigned to different entities. The following entities are proposed: |
| 10 | 53 | Jan Schacher | |
| 11 | 53 | Jan Schacher | > Source, a virtual sound source, emitting sound into the scene. |
| 12 | 53 | Jan Schacher | |
| 13 | 53 | Jan Schacher | > Listener, a virtual sound sink, receiving sound from the scene. |
| 14 | 53 | Jan Schacher | |
| 15 | 53 | Jan Schacher | > Loudspeaker, a real sound source, outputting sound from the scene into the real world |
| 16 | 53 | Jan Schacher | |
| 17 | 53 | Jan Schacher | The index of these entities starts with the number 1. |
| 18 | 53 | Jan Schacher | |
| 19 | 57 | Jan Schacher | > draft SpatDIF OSC-commands would be: |
| 20 | 55 | Jan Schacher | <pre> |
| 21 | 59 | Jan Schacher | /spatdif/core/source/4/gain -12.0 db |
| 22 | 58 | Jan Schacher | |
| 23 | 55 | Jan Schacher | /spatdif/core/listener/1/position 0.5 -0.5 0.0 |
| 24 | 56 | Jan Schacher | |
| 25 | 55 | Jan Schacher | /spatdif/core/speaker/8/position -67.5 0.0 1.0 aed |
| 26 | 1 | </pre> |
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| 27 | 53 | Jan Schacher | |
| 28 | 60 | Jan Schacher | _________ |
| 29 | 53 | Jan Schacher | |
| 30 | 36 | Jan Schacher | h2. Position |
| 31 | 1 | ||
| 32 | 53 | Jan Schacher | > We propose one default coordinate system for describing position data |
| 33 | 1 | ||
| 34 | 22 | Jan Schacher | > a draft SpatDIF OSC-command would be: |
| 35 | 1 | <pre> |
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| 36 | 41 | Jan Schacher | /spatdif/core/source/1/position 1.0 2.4 3.0 |
| 37 | 1 | </pre> |
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| 38 | 1 | ||
| 39 | 53 | Jan Schacher | > it is not decided what this default coordinate system would be. |
| 40 | 41 | Jan Schacher | |
| 41 | 53 | Jan Schacher | > we also allow for using +a few+ alternative coordinate systems: |
| 42 | 22 | Jan Schacher | |
| 43 | 22 | Jan Schacher | > a draft SpatDIF OSC-command for using a spherical system could be: |
| 44 | 1 | <pre> |
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| 45 | 41 | Jan Schacher | /spatdif/core/source/1/position 1.0 2.4 3.0 aed |
| 46 | 1 | </pre> |
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| 47 | 41 | Jan Schacher | |
| 48 | 32 | Jan Schacher | |
| 49 | 1 | > the alternative coordinate system is specified through the string at the end of this message |
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| 50 | 41 | Jan Schacher | |
| 51 | 1 | > in the final SpatDIF specification all alternatives and their related reserved strings are going to be defined |
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| 52 | 37 | Jan Schacher | |
| 53 | 1 | > the alternative coordinate system is only temporarily valid for this specific description |
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| 54 | 1 | ||
| 55 | 53 | Jan Schacher | > it is not decided what these alternative coordinate systems are, here are the [[proposed coordinate systems]] |
| 56 | 18 | Nils Peters | |
| 57 | 53 | Jan Schacher | *see poll results for included coordinate systems [[Current_polls|Poll Results]]* |
| 58 | 1 | ||
| 59 | 1 | ||
| 60 | 61 | Jan Schacher | ________________ |
| 61 | 61 | Jan Schacher | |
| 62 | 1 | h3. Offset feature |
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| 63 | 51 | Jan Schacher | |
| 64 | 62 | Jan Schacher | > The idea is to have an absolute origin of the Coordinate System, then work with local CS offsets. |
| 65 | 64 | Jan Schacher | |
| 66 | 63 | Jan Schacher | > This Concept belongs to geo-transform extension [[Geo-transform_Extension]]. |
| 67 | 1 | ||
| 68 | 5 | Nils Peters | |
| 69 | 60 | Jan Schacher | _______________ |
| 70 | 1 | ||
| 71 | 1 | h2. Gain |
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| 72 | 1 | ||
| 73 | 53 | Jan Schacher | > similarly the gain description is proposed, we propose one default gain unit. |
| 74 | 53 | Jan Schacher | |
| 75 | 43 | Jan Schacher | > a draft SpatDIF OSC-command would be: |
| 76 | 43 | Jan Schacher | <pre> |
| 77 | 5 | Nils Peters | /spatdif/core/source/1/gain 0.9 |
| 78 | 1 | </pre> |
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| 79 | 53 | Jan Schacher | > it is not decided what this default gain unit will be, (probably linear gain) |
| 80 | 53 | Jan Schacher | |
| 81 | 6 | Nils Peters | > we also allow for using a few alternative gain units |
| 82 | 1 | > a draft SpatDIF OSC-command would be: |
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| 83 | 1 | <pre> |
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| 84 | 1 | /spatdif/core/source/1/gain -6.2 db |
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| 85 | 43 | Jan Schacher | </pre> |
| 86 | 53 | Jan Schacher | |
| 87 | 6 | Nils Peters | > the alternative gain unit is specified through the string at the end of this message |
| 88 | 53 | Jan Schacher | |
| 89 | 43 | Jan Schacher | > in the final SpatDIF specification all alternatives and their related reserved string are going to be defined |
| 90 | 53 | Jan Schacher | |
| 91 | 6 | Nils Peters | > the alternative gain unit is only temporarily valid for this specific description |
| 92 | 53 | Jan Schacher | |
| 93 | 1 | > it is not decided yet what these alternative gain units are, here are the [[proposes gain descriptors]] |
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| 94 | 1 | ||
| 95 | 1 | *see poll results for included gain descriptors [[Current_polls|Poll Results]]* |
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| 96 | 7 | Nils Peters | |
| 97 | 60 | Jan Schacher | |
| 98 | 60 | Jan Schacher | ___________ |
| 99 | 7 | Nils Peters | |
| 100 | 44 | Jan Schacher | h2. Distance attenuation function (not discussed yet) |
| 101 | 44 | Jan Schacher | |
| 102 | 44 | Jan Schacher | > A distance according to the position data should be simulated by an attenuation according to the inverse square law |
| 103 | 53 | Jan Schacher | |
| 104 | 52 | Jan Schacher | > alternatively, other distance functions can be applied, e.g. to adapt for different listening environments |
| 105 | 7 | Nils Peters | |
| 106 | 53 | Jan Schacher | > it is not decided what these alternative distance functions are |