Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
シンセサイザー入門
Search
Fadis
May 09, 2015
Programming
0
560
シンセサイザー入門
mbedのDAコンバータを使って色んな方式のシンセサイザーの仕組みを解説します
Fadis
May 09, 2015
Tweet
Share
More Decks by Fadis
See All by Fadis
バイラテラルアップサンプリング
fadis
3
770
Kernel/VM探検隊@関西 11回目 大阪駅から会場までの道のりマップ
fadis
0
240
C++でシェーダを書く
fadis
6
4.9k
ライトたくさんReSTIRを実装しよう
fadis
2
1.3k
コンピュータグラフィクスの空
fadis
7
2.5k
NNEFを読めるようになろう
fadis
0
1.1k
低レイヤーから始める GUI
fadis
18
12k
いまどきのVulkan
fadis
14
7.8k
L2 WireGuard
fadis
2
4.7k
Other Decks in Programming
See All in Programming
Node-RED を(HTTP で)つなげる MCP サーバーを作ってみた
highu
0
120
Google Agent Development Kit でLINE Botを作ってみた
ymd65536
2
250
Flutterで備える!Accessibility Nutrition Labels完全ガイド
yuukiw00w
0
160
PHP 8.4の新機能「プロパティフック」から学ぶオブジェクト指向設計とリスコフの置換原則
kentaroutakeda
2
900
「テストは愚直&&網羅的に書くほどよい」という誤解 / Test Smarter, Not Harder
munetoshi
0
170
Python型ヒント完全ガイド 初心者でも分かる、現代的で実践的な使い方
mickey_kubo
1
110
なぜ「共通化」を考え、失敗を繰り返すのか
rinchoku
1
650
0626 Findy Product Manager LT Night_高田スライド_speaker deck用
mana_takada
0
170
AIと”コードの評価関数”を共有する / Share the "code evaluation function" with AI
euglena1215
1
160
NPOでのDevinの活用
codeforeveryone
0
830
技術同人誌をMCP Serverにしてみた
74th
1
640
Discover Metal 4
rei315
2
130
Featured
See All Featured
Product Roadmaps are Hard
iamctodd
PRO
54
11k
Become a Pro
speakerdeck
PRO
29
5.4k
Practical Orchestrator
shlominoach
189
11k
Site-Speed That Sticks
csswizardry
10
690
How to Create Impact in a Changing Tech Landscape [PerfNow 2023]
tammyeverts
53
2.9k
JavaScript: Past, Present, and Future - NDC Porto 2020
reverentgeek
50
5.5k
Statistics for Hackers
jakevdp
799
220k
The Art of Delivering Value - GDevCon NA Keynote
reverentgeek
15
1.5k
Designing for Performance
lara
610
69k
The Cult of Friendly URLs
andyhume
79
6.5k
What's in a price? How to price your products and services
michaelherold
246
12k
Fashionably flexible responsive web design (full day workshop)
malarkey
407
66k
Transcript
γϯηαΠβʔೖ
দྛঘཧ !GBEJT@ 5XJUUFS ࣗݾհ
দྛঘཧ IUUQTHJUIVCDPN'BEJT HJUIVC͡Ί·ͨ͠ ࠓճհ͢Δίʔυ ͜͜Ͱެ։த ࣗݾհ
ݹͷੲ ୈҰճΧʔωϧ7.୳ݕୂ!ؔ CFFQԻͰԿ͕ग़དྷΔ͔
ࠓճΦʔσΟΦωλ CFFQԻͳΜͯένष͍͜ͱݴΘͣ ΨνͰγϯηαΠβʔΛ࡞Δ
ԻͷपʹΑͬͯԻ֊͕มΘΔ ͜͜ ͜͜
ؚ·Ε͍ͯΔपʹΑͬͯԻ৭͕มΘΔ ͜͜ͱ͔
γϯηαΠβʔͷجຊ ҙਤͨ͠Ի֊ʹରԠ͢ΔपΛ ओͱ͢ΔΛ࡞Δ
ྲྀߦͷϚΠίϯNCFE͞Μ AnalogOut
#include "mbed.h" AnalogOut audio_out(p18); const float freq_table[ 8 ] =
{ 523.25113f, 587.32953f, 659.25511f, 698.45646f, 783.99087f, 880.00000f, 987.76660f, 1046.5022f, }; int main() { while(1) { for( int note = 0; note != 8; ++note ) for( float time = 0.0f; time < 1.0f; time += 1.0f/16000.0f ) { Timer used_time; used_time.start(); audio_out = sinf( time * freq_table[ note ] * 3.141592f * 2.0f ) * 0.5f + 0.5f; used_time.stop(); wait(1.0f/16000.0f-used_time.read()); } } }
αΠζͷ߹ͰಈըΧοτʜ
ͬͱෳࡶͳԻΛग़͍ͨ͠ ϑΝϛίϯۣܗͱࡾ֯ͷ छྨͷܗ͔͑͠ͳ͍ͷʹ ଟ࠼ͳԻ৭ΛͰΔ͜ͱ͕ग़དྷΔͷԿނ͔ ۣܗ ࡾ֯
Τϯϕϩʔϓ ͬͱෳࡶͳԻΛग़͍ͨ͠ ԻྔΛܦա࣌ؒʹԠͯ͡มԽͤ͞Δ ͜͜Ͱ໐Β͢ͷΛΊͨ ͜͜Ͱ໐Β͠͡Ίͨ
ΞλοΫ ϐΞϊ όΠΦϦϯ ໐Γ͡Ίͷ Իྔ͕࠷େ͖͍ ໐Γ͡Ί͔ͯΒ ঃʑʹԻྔ͕େ͖͘ͳΔ ͜ͷ෦ͷ͞Λม͑Δ͜ͱͰରԠ
σΟέΠ γϩϑΥϯ Ϊλʔ ໐Β͠͡Ίͯ࠷େԻྔʹୡͨ͠ޙ ͙͢ʹԻྔ͕Լ͕Δ ໐Β͠͡Ίͯ࠷େԻྔʹୡͨ͠ޙ Ώͬ͘ΓԻྔ͕Լ͕Δ ͜ͷ෦ͷ͞Λม͑Δ͜ͱͰରԠ
αεςΠϯ ϐΞϊ ΦϧΨϯ ݤ൫Λԡ͍ͯ͠Δ࣌ؒʹؔΘΒͣ ͋Δఔͷ࣌ؒͰԻ͕ফ͑Δ ݤ൫Λԡ͍ͯ͠ΔݶΓࡍݶͳ͘ Ի͕໐Γଓ͚Δ ͜ͷ෦ͷେ͖͞Λม͑Δ͜ͱͰରԠ
ϦϦʔε ΦϧΨϯ ενʔϧυϥϜ ͘ͷΛΊΔͱ ൺֱత࣌ؒͰԻ͕ফ͑Δ ͜ͷ෦ͷ͖Λม͑Δ͜ͱͰରԠ ͘ͷΛΊͯԻ͕ ফ͑Δ·Ͱʹ͋Δఔͷ࣌ؒΛཁ͢
Τϯϕϩʔϓ º
#include "mbed.h" AnalogOut audio_out(p18); DigitalIn button(p19); class Envelope { bool
note_stat; float prev; public: Envelope() : note_stat( true ), prev( 0.0f ) {} void off() { note_stat = false; } float operator()( float _time ) { if( note_stat ) { if( _time < 0.2f ) prev = _time / 0.2f; else if( _time < 0.7f ) prev = 1.0f - ( _time - 0.2f ); else prev = 0.5f; return prev; } else return ( prev - _time < 0.0f ) ? 0.0f : prev - _time; } }; int main() { while(1) { Envelope envelope; float time, note_off_time; for( time = 0.0f; button; time += 1.0f/16000.0f ) { Timer used_time; used_time.start(); audio_out = envelope( time ) * sinf( time * 880.0f * 3.141592f * 2.0f ) * 0.4f + 0.5f; used_time.stop(); wait(1.0f/16000.0f-used_time.read()); } envelope.off(); for( note_off_time = time; !button; time += 1.0f/16000.0f ) { Timer used_time; used_time.start(); audio_out = envelope( time - note_off_time ) * sinf( time * 880.0f * 3.141592f * 2.0f ) * 0.4f + 0.5f; used_time.stop(); wait(1.0f/16000.0f-used_time.read()); } } }
αΠζͷ߹ͰಈըΧοτʜ
ϋϞϯυΦϧΨϯ αΠϯͱ͔ۣܗͱ͔Ͱͳ͘ ͬͱෳࡶͳܗΛ͏͜ͱͰ ଟ࠼ͳԻ৭ΛͰ͍ͨ ෳͷαΠϯΛॏͶ߹ΘͤΔ ࡞ઓ
ϋϞϯυΦϧΨϯ ഒ ഒ ഒ ഒ ̏ഒ ̐ഒ ഒ ̒ഒ ഒ
جԻ ͜ΕΒͷഒԻΛҙͷԻྔͰॏͶ߹ΘͤΔ
ϋϞϯυΦϧΨϯ ຊͷϋϞϯυΦϧΨϯ αΠϯͷࠁ·Εͨຕͷԁ൫Λ ߴճసͤ͞Δ͜ͱͰ֤पͷΛ࡞͍ͬͯͨ ϚΠίϯͰ؆୯ʹαΠϯΛ࡞ΕΔ࣌Ͱ ຊʹྑ͔ͬͨ
... template< typename Traits > class Hammond { public: Hammond(){}
fixed32< 16 > operator()( fixed32< 16 > _time ) { static const fixed32< 16 > scale_16 = 220.0f; static const fixed32< 16 > scale_8 = 440.0f; static const fixed32< 16 > scale_513 = 659.3f; static const fixed32< 16 > scale_4 = 880.0f; static const fixed32< 16 > scale_223 = 1318.5f; static const fixed32< 16 > scale_2 = 1760.0f; static const fixed32< 16 > scale_135 = 2217.0f; static const fixed32< 16 > scale_113 = 2637.0f; static const fixed32< 16 > scale_1 = 3520.0f; fixed32< 16 > sum = 0.0f; sum += sint( _time * scale_16 ) * Traits::level_16; sum += sint( _time * scale_8 ) * Traits::level_8; sum += sint( _time * scale_513 ) * Traits::level_513; sum += sint( _time * scale_4 ) * Traits::level_4; sum += sint( _time * scale_223 ) * Traits::level_223; sum += sint( _time * scale_2 ) * Traits::level_2; sum += sint( _time * scale_135 ) * Traits::level_135; sum += sint( _time * scale_113 ) * Traits::level_113; sum += sint( _time * scale_1) * Traits::level_1; fixed32< 16 > max = 0.0f; max += Traits::level_16; max += Traits::level_8; max += Traits::level_513; max += Traits::level_4; max += Traits::level_223; max += Traits::level_2; max += Traits::level_135; max += Traits::level_113; max += Traits::level_1; sum /= max; return sum; } private: }; ...
αΠζͷ߹ͰಈըΧοτʜ
ϋϞϯυΦϧΨϯ ϑʔϦΤڃΑΓ ͋ΒΏΔܗαΠϯͷॏͶ߹ΘͤͰ࡞ΕΔ͕ Ұൠʹेͳ࣭ΛಘΔҝʹཁٻ͞ΕΔ αΠϯͷඇৗʹଟ͘ ͔͔ͨͩݸఔͷαΠϯͰ େͨ͠Ի৭ͷࣗ༝ಘΒΕͳ͍
'.Իݯ αΠϯͱ͔ۣܗͱ͔Ͱͳ͘ ͬͱෳࡶͳܗΛ͏͜ͱͰ ଟ࠼ͳԻ৭ΛͰ͍ͨ '.มௐΛͬͯαΠϯΛΊΔ ࡞ઓ
ΦϖϨʔλ PVUQVUTJO DMPDL JOQVU FOWFMPQF ·ͨผͷΦϖϨʔλ ΦʔσΟΦग़ྗ·ͨผͷΦϖϨʔλ
ΦϖϨʔλྻͷ'.Իݯ ΦϖϨʔλ ΦϖϨʔλ ΦʔσΟΦग़ྗ
ΦϖϨʔλฒྻͷ'.Իݯ ΦϖϨʔλ ΦϖϨʔλ ΦʔσΟΦग़ྗ
ೖྗଆͷԻྔͰΈ۩߹͕ௐઅͰ͖Δ ΦϖϨʔλ ΦϖϨʔλ ΦϖϨʔλ ΦϖϨʔλ
ೖྗଆͷԻྔͰΈ۩߹͕ௐઅͰ͖Δ PVUQVUTJO DMPDL JOQVU FOWFMPQF ΦϖϨʔλʹ Τϯϕϩʔϓ͕͍͍ͭͯΔ ΦʔσΟΦग़ྗʹܨ͕͍ͬͯͳ͍ ΦϖϨʔλͷΤϯϕϩʔϓ
ܗͷΈΛ࣌ؒมԽͤ͞ΔͨΊʹ͑Δ
... class Const { public: fixed32< 16 > operator()( fixed32<
16 > _time ) { static const fixed32< 16 > value = 0; return value; } }; ! template< typename Source > class FM { public: FM() {} void off( fixed32< 16 > _off_time ) { envelope.off( _off_time ); } fixed32< 16 > operator()( fixed32< 16 > _time ) { fixed32< 16 > looped_time = _time - static_cast< int >( _time ); return sint( ( looped_time * 880.0f + source( _time ) / 2 ) ) * envelope( _time ); } private: Source source; Envelope envelope; }; ! int main() { while(1) { FM< FM< Const > > fm; fixed32< 16 > time, note_off_time; for( time = 0.0f; button; time += 1.0f/16000.0f ) { Timer used_time; used_time.start(); audio_out = fm( time ) * 0.4f + 0.5f; used_time.stop(); wait(1.0f/16000.0f-used_time.read()); } fm.off( time ); ...
αΠζͷ߹ͰಈըΧοτʜ
'.Իݯ '.มௐͷ݁Ռײతʹ༧͠ਏ͍ͨΊ ҙਤͨ͠Ի৭Λ࡞ΔͨΊʹࢼߦࡨޡ͕ඞཁ
ܗςʔϒϧԻݯ αΠϯͱ͔ۣܗͱ͔Ͱͳ͘ ͬͱෳࡶͳܗΛ͏͜ͱͰ ଟ࠼ͳԻ৭ΛͰ͍ͨ ࣄલʹ༻ҙͨ͠ܗσʔλΛ͏ ࡞ઓ
ܗςʔϒϧԻݯ ٕज़తʹ໘ന͘ͳ͍͚Ͳ ͦΕͳΓʹྑ͍Ի͕ग़Δํ๏ ͋Β͔͡Ίຊͷָث͔ΒԻ͖ͯͨ͠ ܗσʔλΛԻ֊ʹରԠ͢Δ͞ͰᢞΊΔ ྻ
... class Guiter { public: virtual fixed32< 16 > operator()(
fixed32< 16 > _pos ) { static const int16_t guiter_table[ 512 ] = { -32735, -32583, -32431, -32279, -32127, -31975, -31823, -31671, ... -27519, -28171, -28823, -29475, -30127, -30779, -31431, -32083, }; fixed32< 16 > result; fixed32< 16 > a4 = _pos * 220.0f; int pos = ( a4.get() >> 7 ) % 512; // pos = pos * 880 % 512; int32_t value = static_cast< int32_t >( guiter_table[ pos ] ) << 1; result.set( value ); return result * envelope( _pos ); } void off( fixed32< 16 > _off_time ) { envelope.off( _off_time ); } private: Envelope envelope; }; ...
αΠζͷ߹ͰಈըΧοτʜ
ܗςʔϒϧԻݯ ࣮ͷଘࡏ͠ͳ͍ԻΛ࡞Δͷࠔ ࣌ؒมԽ͢ΔԻ৭Λѻ͏ͷ͕ࠔ
࠷ऴతʹग़དྷ্͕ͬͨͷ ͦͷଞ৭ʑ࣮͚ͨ͠Ͳ ͦͷΜͷղઆ·ͨͷػձʹ Ψοπͷ͋Δਓ ιʔεΛݟͯΈΔͱ͍͍͔
IUUQZPVUVCFSY5RX&:#.
ษڧձ෮शࢿྉ IUUQCJUMZF2,WE& ιʔείʔυ IUUQCJUMZRJBR'
͝ਗ਼ௌ͋Γ͕ͱ͏͍͟͝·ͨ͠