DSP (File Format) - Revision history

Aruki: /* Header */

2015-02-09T04:42:58Z

‎Header

2015-02-09T04:41:37Z

‎Header: adding types

2015-01-28T17:01:19Z

Removing filedone template. Should we keep that template around so we can have a category for fully documented formats?

2015-01-26T03:34:21Z

‎Header

2015-01-25T21:42:15Z

Added completed file format notice

2015-01-25T13:39:19Z

2015-01-25T12:41:36Z

2015-01-24T18:20:35Z

‎Header

2015-01-24T18:19:59Z

‎Header

2015-01-24T18:10:17Z

@@ Line 99: / Line 99: @@
 |-
 | 0x60
-| colspan=2 {{unknown|End of DSP header}}
+| colspan=3 {{unknown|End of DSP header}}
 |}

@@ Line 9: / Line 9: @@
 {| class="wikitable"
 ! Offset
 ! Size
 ! Description
 |-
 | 0x0
 | 4
 | '''Sample count'''
 |-
 | 0x4
 | 4
 | '''ADPCM nibble count'''; includes frame headers
 |-
 | 0x8
 | 4
 | '''Sample rate'''
 |-
 | 0xC
 | 2
 | '''Loop flag'''; 1 means looped, 0 means not looped
 |-
 | 0xE
 | 2
 | '''Format'''; always 0
 |-
 | 0x10
 | 4
 | '''Loop start offset'''
 |-
 | 0x14
 | 4
 | '''Loop end offset'''
 |-
 | 0x18
 | 4
 | '''Current address'''; always 0
 |-
 | 0x1C
 | 2 &times; 16
 | '''Decode coefficients'''; this is 8 pairs of signed 16-bit values
 |-
 | 0x3C
 | 2
 | '''Gain'''; always 0
 |-
 | 0x3E
 | 2
 | '''Initial predictor/scale'''; always matches first frame header
 |-
 | 0x40
 | 2
 | '''Initial sample history 1'''
 |-
 | 0x42
 | 2
 | '''Initial sample history 2'''
 |-
 | 0x44
 | 2
 | '''Loop context predictor/scale'''
 |-
 | 0x46
 | 2
 | '''Loop context sample history 1'''
 |-
 | 0x48
 | 2
 | '''Loop context sample history 2'''
 |-
 | 0x4A
 | 2 &times; 11
 | '''Reserved'''

← Older revision		Revision as of 17:01, 28 January 2015
Line 1:		Line 1:
	The '''.dsp format''' is a common GameCube/Wii format for audio that comes with the SDK. It encodes sound using Nintendo's ADPCM codec. The same ADPCM codec is also embedded into several Retro Studios format, like [[AGSC (File Format)\|AGSC]]; the [[CSMP (File Format)\|CSMP]] format actually embeds the entire DSP format within it.		The '''.dsp format''' is a common GameCube/Wii format for audio that comes with the SDK. It encodes sound using Nintendo's ADPCM codec. The same ADPCM codec is also embedded into several Retro Studios format, like [[AGSC (File Format)\|AGSC]]; the [[CSMP (File Format)\|CSMP]] format actually embeds the entire DSP format within it.
−
−	~~{{Filedone}}~~

	{{todo\|An explanation of how ADPCM works would be nice to have somewhere on this page. Also, a better text explanation for the decoding process to go along with the example code.}}		{{todo\|An explanation of how ADPCM works would be nice to have somewhere on this page. Also, a better text explanation for the decoding process to go along with the example code.}}

@@ Line 83: / Line 83: @@
 |-
 | 0x60
-| colspan=2 | End of DSP header
+| colspan=2 {{unknown|End of DSP header}}
 |}

← Older revision		Revision as of 21:42, 25 January 2015
Line 1:		Line 1:
	The '''.dsp format''' is a common GameCube/Wii format for audio that comes with the SDK. It encodes sound using Nintendo's ADPCM codec. The same ADPCM codec is also embedded into several Retro Studios format, like [[AGSC (File Format)\|AGSC]]; the [[CSMP (File Format)\|CSMP]] format actually embeds the entire DSP format within it.		The '''.dsp format''' is a common GameCube/Wii format for audio that comes with the SDK. It encodes sound using Nintendo's ADPCM codec. The same ADPCM codec is also embedded into several Retro Studios format, like [[AGSC (File Format)\|AGSC]]; the [[CSMP (File Format)\|CSMP]] format actually embeds the entire DSP format within it.
		+
		+	{{Filedone}}

	{{todo\|An explanation of how ADPCM works would be nice to have somewhere on this page. Also, a better text explanation for the decoding process to go along with the example code.}}		{{todo\|An explanation of how ADPCM works would be nice to have somewhere on this page. Also, a better text explanation for the decoding process to go along with the example code.}}

@@ Line 18: / Line 18: @@
 | 0x4
 | 4
-| '''ADPCM nibble count'''
+| '''ADPCM nibble count'''; includes frame headers
 |-
 | 0x8
@@ Line 86: / Line 86: @@
 == ADPCM Data ==
-The ADPCM audio data is split up into multiple ''frames''. Each frame is 8 bytes; it starts with a one-byte header, then has 7 bytes (or 14 samples) of audio data. For each frame, the bottom 4 bits are the scale value, and the top 4 bits are the coefficient index to use for the current frame.
+The ADPCM audio data is split up into multiple ''frames''. Each frame is 8 bytes; it starts with a one-byte header, then has 7 bytes (or 14 samples) of audio data. For each frame header, the bottom 4 bits are the scale value, and the top 4 bits are the coefficient index to use for the current frame.
 === Example C Decoding Function ===
@@ Line 121: / Line 121: @@
      u16 scale = 1 << (header & 0xF);
      u8 coef_index = (header >> 4);
-     s16 coef1 = d.coefs[coef_index * 2];
+     s16 coef1 = d.coefs[coef_index][0];
-     s16 coef2 = d.coefs[coef_index * 2 + 1];
+     s16 coef2 = d.coefs[coef_index][1];
      // 7 bytes per frame

← Older revision		Revision as of 12:41, 25 January 2015
Line 1:		Line 1:
	The '''.dsp format''' is a common GameCube/Wii format for audio that comes with the SDK. It encodes sound using Nintendo's ADPCM codec. The same ADPCM codec is also embedded into several Retro Studios format, like [[AGSC (File Format)\|AGSC]]; the [[CSMP (File Format)\|CSMP]] format actually embeds the entire DSP format within it.		The '''.dsp format''' is a common GameCube/Wii format for audio that comes with the SDK. It encodes sound using Nintendo's ADPCM codec. The same ADPCM codec is also embedded into several Retro Studios format, like [[AGSC (File Format)\|AGSC]]; the [[CSMP (File Format)\|CSMP]] format actually embeds the entire DSP format within it.
		+
		+	{{todo\|An explanation of how ADPCM works would be nice to have somewhere on this page. Also, a better text explanation for the decoding process to go along with the example code.}}

	__TOC__		__TOC__

@@ Line 40: / Line 40: @@
 | 0x18
 | 4
-| Always 0
+| '''Current address'''; always 0
 |-
 | 0x1C

@@ Line 82: / Line 82: @@
 |}
-== Audio Data ==
+== ADPCM Data ==
 The ADPCM audio data is split up into multiple ''frames''. Each frame is 8 bytes; it starts with a one-byte header, then has 7 bytes (or 14 samples) of audio data. For each frame, the bottom 4 bits are the scale value, and the top 4 bits are the coefficient index to use for the current frame.
-Sample decoding code ([https://github.com/kode54/vgmstream/blob/master/src/coding/ngc_dsp_decoder.c vgmstream] used as reference):
+=== Example C Decoding Function ===
 <syntaxhighlight lang="c">static const s8 nibble_to_s8[16] = {0,1,2,3,4,5,6,7,-8,-7,-6,-5,-4,-3,-2,-1};