nihav-core/src/soundcvt/mod.rs

   1 //! Sound format conversion.
   2 //!
   3 //! This module implements the functionality for conversion between different sound formats: packed or planar audio, 8-/16-/24-/32-bit, integer or floating point, different number of channels.
   4 //! Eventually this might support resampling as well.
   5 pub use crate::formats::{NASoniton,NAChannelMap};
   6 pub use crate::frame::{NAAudioBuffer,NAAudioInfo,NABufferType};
   7 use crate::formats::NAChannelType;
   8 use crate::frame::alloc_audio_buffer;
   9 use crate::io::byteio::*;
  10 use std::f32::consts::SQRT_2;
  11
  12 /// A list specifying general sound conversion errors.
  13 #[derive(Clone,Copy,Debug,PartialEq)]
  14 pub enum SoundConvertError {
  15     /// Invalid input arguments.
  16     InvalidInput,
  17     /// Allocation failed.
  18     AllocError,
  19     /// Requested feature is not supported.
  20     Unsupported,
  21 }
  22
  23 enum ChannelOp {
  24     Passthrough,
  25     Reorder(Vec<usize>),
  26     Remix(Vec<f32>),
  27     DupMono(Vec<bool>),
  28 }
  29
  30 impl ChannelOp {
  31     fn is_remix(&self) -> bool {
  32         match *self {
  33             ChannelOp::Remix(_) => true,
  34             ChannelOp::DupMono(_) => true,
  35             _ => false,
  36         }
  37     }
  38 }
  39
  40 fn apply_channel_op<T:Copy>(ch_op: &ChannelOp, src: &[T], dst: &mut Vec<T>) {
  41     match *ch_op {
  42         ChannelOp::Passthrough => {
  43             dst.copy_from_slice(src);
  44         },
  45         ChannelOp::Reorder(ref reorder) => {
  46             for (out, idx) in dst.iter_mut().zip(reorder.iter()) {
  47                 *out = src[*idx];
  48             }
  49         },
  50         _ => {},
  51     };
  52 }
  53
  54 fn remix_i32(ch_op: &ChannelOp, src: &[i32], dst: &mut Vec<i32>) {
  55     if let ChannelOp::Remix(ref remix_mat) = ch_op {
  56         let sch = src.len();
  57         for (out, coeffs) in dst.iter_mut().zip(remix_mat.chunks(sch)) {
  58             let mut sum = 0.0;
  59             for (inval, coef) in src.iter().zip(coeffs.iter()) {
  60                 sum += (*inval as f32) * *coef;
  61             }
  62             *out = sum as i32;
  63         }
  64     }
  65     if let ChannelOp::DupMono(ref dup_mat) = ch_op {
  66         let src = src[0];
  67         for (out, copy) in dst.iter_mut().zip(dup_mat.iter()) {
  68             *out = if *copy { src } else { 0 };
  69         }
  70     }
  71 }
  72
  73 fn remix_f32(ch_op: &ChannelOp, src: &[f32], dst: &mut Vec<f32>) {
  74     if let ChannelOp::Remix(ref remix_mat) = ch_op {
  75         let sch = src.len();
  76         for (out, coeffs) in dst.iter_mut().zip(remix_mat.chunks(sch)) {
  77             let mut sum = 0.0;
  78             for (inval, coef) in src.iter().zip(coeffs.iter()) {
  79                 sum += *inval * *coef;
  80             }
  81             *out = sum;
  82         }
  83     }
  84     if let ChannelOp::DupMono(ref dup_mat) = ch_op {
  85         let src = src[0];
  86         for (out, copy) in dst.iter_mut().zip(dup_mat.iter()) {
  87             *out = if *copy { src } else { 0.0 };
  88         }
  89     }
  90 }
  91
  92 trait FromFmt<T:Copy> {
  93     fn cvt_from(val: T) -> Self;
  94 }
  95
  96 impl FromFmt<u8> for u8 {
  97     fn cvt_from(val: u8) -> u8 { val }
  98 }
  99 impl FromFmt<u8> for i16 {
 100     fn cvt_from(val: u8) -> i16 { u16::from(val ^ 0x80).wrapping_mul(0x101) as i16}
 101 }
 102 impl FromFmt<u8> for i32 {
 103     fn cvt_from(val: u8) -> i32 { u32::from(val ^ 0x80).wrapping_mul(0x01010101) as i32 }
 104 }
 105 impl FromFmt<u8> for f32 {
 106     fn cvt_from(val: u8) -> f32 { (f32::from(val) - 128.0) / 128.0 }
 107 }
 108
 109 impl FromFmt<i16> for u8 {
 110     fn cvt_from(val: i16) -> u8 { ((val >> 8) + 128).min(255).max(0) as u8 }
 111 }
 112 impl FromFmt<i16> for i16 {
 113     fn cvt_from(val: i16) -> i16 { val }
 114 }
 115 impl FromFmt<i16> for i32 {
 116     fn cvt_from(val: i16) -> i32 { (i32::from(val) & 0xFFFF) | (i32::from(val) << 16) }
 117 }
 118 impl FromFmt<i16> for f32 {
 119     fn cvt_from(val: i16) -> f32 { f32::from(val) / 32768.0 }
 120 }
 121
 122 impl FromFmt<i32> for u8 {
 123     fn cvt_from(val: i32) -> u8 { ((val >> 24) + 128).min(255).max(0) as u8 }
 124 }
 125 impl FromFmt<i32> for i16 {
 126     fn cvt_from(val: i32) -> i16 { (val >> 16) as i16 }
 127 }
 128 impl FromFmt<i32> for i32 {
 129     fn cvt_from(val: i32) -> i32 { val }
 130 }
 131 impl FromFmt<i32> for f32 {
 132     fn cvt_from(val: i32) -> f32 { (val as f32) / 31.0f32.exp2() }
 133 }
 134
 135 impl FromFmt<f32> for u8 {
 136     fn cvt_from(val: f32) -> u8 { ((val * 128.0) + 128.0).min(255.0).max(0.0) as u8 }
 137 }
 138 impl FromFmt<f32> for i16 {
 139     fn cvt_from(val: f32) -> i16 { (val * 32768.0).min(32767.0).max(-32768.0) as i16 }
 140 }
 141 impl FromFmt<f32> for i32 {
 142     fn cvt_from(val: f32) -> i32 {
 143         if val >= 1.0 {
 144             std::i32::MAX
 145         } else if val <= -1.0 {
 146             std::i32::MIN
 147         } else {
 148             let scale = (1u32 << 31) as f32;
 149             (val * scale) as i32
 150         }
 151     }
 152 }
 153 impl FromFmt<f32> for f32 {
 154     fn cvt_from(val: f32) -> f32 { val }
 155 }
 156
 157 trait IntoFmt<T:Copy> {
 158     fn cvt_into(self) -> T;
 159 }
 160
 161 impl<T:Copy, U:Copy> IntoFmt<U> for T where U: FromFmt<T> {
 162     fn cvt_into(self) -> U { U::cvt_from(self) }
 163 }
 164
 165
 166 trait SampleReader {
 167     fn get_samples_i32(&self, pos: usize, dst: &mut Vec<i32>);
 168     fn get_samples_f32(&self, pos: usize, dst: &mut Vec<f32>);
 169 }
 170
 171 struct GenericSampleReader<'a, T:Copy> {
 172     data:   &'a [T],
 173     stride: usize,
 174 }
 175
 176 impl<'a, T:Copy+IntoFmt<i32>+IntoFmt<f32>> SampleReader for GenericSampleReader<'a, T> {
 177     fn get_samples_i32(&self, pos: usize, dst: &mut Vec<i32>) {
 178         let mut off = pos;
 179         for el in dst.iter_mut() {
 180             *el = self.data[off].cvt_into();
 181             off += self.stride;
 182         }
 183     }
 184     fn get_samples_f32(&self, pos: usize, dst: &mut Vec<f32>) {
 185         let mut off = pos;
 186         for el in dst.iter_mut() {
 187             *el = self.data[off].cvt_into();
 188             off += self.stride;
 189         }
 190     }
 191 }
 192
 193 struct S8SampleReader<'a> {
 194     data:   &'a [u8],
 195     stride: usize,
 196 }
 197
 198 impl<'a> SampleReader for S8SampleReader<'a> {
 199     fn get_samples_i32(&self, pos: usize, dst: &mut Vec<i32>) {
 200         let mut off = pos;
 201         for el in dst.iter_mut() {
 202             *el = (self.data[off] ^ 0x80).cvt_into();
 203             off += self.stride;
 204         }
 205     }
 206     fn get_samples_f32(&self, pos: usize, dst: &mut Vec<f32>) {
 207         let mut off = pos;
 208         for el in dst.iter_mut() {
 209             *el = (self.data[off] ^ 0x80).cvt_into();
 210             off += self.stride;
 211         }
 212     }
 213 }
 214
 215 struct PackedSampleReader<'a> {
 216     data:   &'a [u8],
 217     fmt:    NASoniton,
 218     bpp:    usize,
 219 }
 220
 221 impl<'a> PackedSampleReader<'a> {
 222     fn new(data: &'a [u8], fmt: NASoniton) -> Self {
 223         if (fmt.bits & 7) != 0 { unimplemented!(); }
 224         let bpp = (fmt.bits >> 3) as usize;
 225         Self { data, fmt, bpp }
 226     }
 227     fn get_samples<T:Copy>(&self, pos: usize, dst: &mut Vec<T>) where u8: IntoFmt<T>, i16: IntoFmt<T>, i32: IntoFmt<T>, f32: IntoFmt<T> {
 228         let mut offset = pos * self.bpp * dst.len();
 229
 230         for el in dst.iter_mut() {
 231             let src = &self.data[offset..];
 232             *el = if !self.fmt.float {
 233                     match (self.bpp, self.fmt.be) {
 234                         (1, _)     => if !self.fmt.signed { src[0].cvt_into() } else { (src[0] ^ 0x80).cvt_into() },
 235                         (2, true)  => (read_u16be(src).unwrap() as i16).cvt_into(),
 236                         (2, false) => (read_u16le(src).unwrap() as i16).cvt_into(),
 237                         (3, true)  => ((read_u24be(src).unwrap() << 8) as i32).cvt_into(),
 238                         (3, false) => ((read_u24be(src).unwrap() << 8) as i32).cvt_into(),
 239                         (4, true)  => (read_u32be(src).unwrap() as i32).cvt_into(),
 240                         (4, false) => (read_u32be(src).unwrap() as i32).cvt_into(),
 241                         _ => unreachable!(),
 242                     }
 243                 } else {
 244                     match (self.bpp, self.fmt.be) {
 245                         (4, true)  => read_f32be(src).unwrap().cvt_into(),
 246                         (4, false) => read_f32le(src).unwrap().cvt_into(),
 247                         (8, true)  => (read_f64be(src).unwrap() as f32).cvt_into(),
 248                         (8, false) => (read_f64le(src).unwrap() as f32).cvt_into(),
 249                         (_, _) => unreachable!(),
 250                     }
 251                 };
 252             offset += self.bpp;
 253         }
 254     }
 255 }
 256
 257 impl SampleReader for PackedSampleReader<'_> {
 258     fn get_samples_i32(&self, pos: usize, dst: &mut Vec<i32>) {
 259         self.get_samples(pos, dst);
 260     }
 261     fn get_samples_f32(&self, pos: usize, dst: &mut Vec<f32>) {
 262         self.get_samples(pos, dst);
 263     }
 264 }
 265
 266 trait SampleWriter {
 267     fn store_samples_i32(&mut self, pos: usize, src: &[i32]);
 268     fn store_samples_f32(&mut self, pos: usize, src: &[f32]);
 269 }
 270
 271 struct GenericSampleWriter<'a, T:Copy> {
 272     data:   &'a mut [T],
 273     stride: usize,
 274 }
 275
 276 impl<'a, T:Copy+FromFmt<i32>+FromFmt<f32>> SampleWriter for GenericSampleWriter<'a, T> {
 277     fn store_samples_i32(&mut self, pos: usize, src: &[i32]) {
 278         let mut off = pos;
 279         for el in src.iter() {
 280             self.data[off] = (*el).cvt_into();
 281             off += self.stride;
 282         }
 283     }
 284     fn store_samples_f32(&mut self, pos: usize, src: &[f32]) {
 285         let mut off = pos;
 286         for el in src.iter() {
 287             self.data[off] = (*el).cvt_into();
 288             off += self.stride;
 289         }
 290     }
 291 }
 292
 293 struct PackedSampleWriter<'a> {
 294     data:   &'a mut [u8],
 295     fmt:    NASoniton,
 296     bpp:    usize,
 297 }
 298
 299 impl<'a> PackedSampleWriter<'a> {
 300     fn new(data: &'a mut [u8], fmt: NASoniton) -> Self {
 301         if (fmt.bits & 7) != 0 { unimplemented!(); }
 302         let bpp = (fmt.bits >> 3) as usize;
 303         Self { data, fmt, bpp }
 304     }
 305
 306     fn store_samples<T:Copy>(&mut self, pos: usize, src: &[T]) where u8: FromFmt<T>, i16: FromFmt<T>, i32: FromFmt<T>, f32: FromFmt<T> {
 307         let mut offset = pos * self.bpp * src.len();
 308         for el in src.iter() {
 309             let dst = &mut self.data[offset..];
 310             if !self.fmt.float {
 311                 match (self.bpp, self.fmt.be) {
 312                     (1, _) => {
 313                         dst[0] = u8::cvt_from(*el);
 314                         if self.fmt.signed {
 315                             dst[0] ^= 0x80;
 316                         }
 317                     },
 318                     (2, true)  => write_u16be(dst, i16::cvt_from(*el) as u16).unwrap(),
 319                     (2, false) => write_u16le(dst, i16::cvt_from(*el) as u16).unwrap(),
 320                     (3, true)  => write_u24be(dst, (i32::cvt_from(*el) >> 8) as u32).unwrap(),
 321                     (3, false) => write_u24le(dst, (i32::cvt_from(*el) >> 8) as u32).unwrap(),
 322                     (4, true)  => write_u32be(dst, i32::cvt_from(*el) as u32).unwrap(),
 323                     (4, false) => write_u32le(dst, i32::cvt_from(*el) as u32).unwrap(),
 324                     _ => unreachable!(),
 325                 };
 326             } else {
 327                 match (self.bpp, self.fmt.be) {
 328                     (4, true)  => write_f32be(dst, f32::cvt_from(*el)).unwrap(),
 329                     (4, false) => write_f32le(dst, f32::cvt_from(*el)).unwrap(),
 330                     (8, true)  => write_f64be(dst, f64::from(f32::cvt_from(*el))).unwrap(),
 331                     (8, false) => write_f64le(dst, f64::from(f32::cvt_from(*el))).unwrap(),
 332                     (_, _) => unreachable!(),
 333                 };
 334             }
 335             offset += self.bpp;
 336         }
 337     }
 338 }
 339
 340 impl SampleWriter for PackedSampleWriter<'_> {
 341     fn store_samples_i32(&mut self, pos: usize, src: &[i32]) {
 342         self.store_samples(pos, src);
 343     }
 344     fn store_samples_f32(&mut self, pos: usize, src: &[f32]) {
 345         self.store_samples(pos, src);
 346     }
 347 }
 348
 349 /// Converts input audio buffer into desired format and returns a newly allocated buffer.
 350 pub fn convert_audio_frame(src: &NABufferType, dst_info: &NAAudioInfo, dst_chmap: &NAChannelMap) ->
 351 Result<NABufferType, SoundConvertError> {
 352     let mut nsamples = src.get_audio_length();
 353     if nsamples == 0 {
 354         return Err(SoundConvertError::InvalidInput);
 355     }
 356     let src_chmap = src.get_chmap().unwrap();
 357     let src_info  = src.get_audio_info().unwrap();
 358     if (src_chmap.num_channels() == 0) || (dst_chmap.num_channels() == 0) {
 359         return Err(SoundConvertError::InvalidInput);
 360     }
 361
 362     if let NABufferType::AudioPacked(_) = src {
 363         nsamples = nsamples * 8 / (src_info.get_format().get_bits() as usize) / src_chmap.num_channels();
 364     }
 365
 366     let needs_remix = src_chmap.num_channels() != dst_chmap.num_channels();
 367     let no_channel_needs = !needs_remix && channel_maps_equal(src_chmap, dst_chmap);
 368     let needs_reorder = !needs_remix && !no_channel_needs && channel_maps_reordered(src_chmap, dst_chmap);
 369
 370     let channel_op = if no_channel_needs {
 371             ChannelOp::Passthrough
 372         } else if needs_reorder {
 373             let reorder_mat = calculate_reorder_matrix(src_chmap, dst_chmap);
 374             ChannelOp::Reorder(reorder_mat)
 375         } else if src_chmap.num_channels() > 1 {
 376             let remix_mat = calculate_remix_matrix(src_chmap, dst_chmap);
 377             ChannelOp::Remix(remix_mat)
 378         } else {
 379             let mut dup_mat: Vec<bool> = Vec::with_capacity(dst_chmap.num_channels());
 380             for i in 0..dst_chmap.num_channels() {
 381                 let ch =  dst_chmap.get_channel(i);
 382                 if ch.is_left() || ch.is_right() || ch == NAChannelType::C {
 383                     dup_mat.push(true);
 384                 } else {
 385                     dup_mat.push(false);
 386                 }
 387             }
 388             ChannelOp::DupMono(dup_mat)
 389         };
 390
 391     let src_fmt = src_info.get_format();
 392     let dst_fmt = dst_info.get_format();
 393     let no_conversion = src_fmt == dst_fmt;
 394
 395     if no_conversion && no_channel_needs {
 396         return Ok(src.clone());
 397     }
 398
 399     let ret = alloc_audio_buffer(*dst_info, nsamples, dst_chmap.clone());
 400     if ret.is_err() {
 401         return Err(SoundConvertError::AllocError);
 402     }
 403     let mut dst_buf = ret.unwrap();
 404
 405     let sstep = src.get_audio_step().max(1);
 406     let dstep = dst_buf.get_audio_step().max(1);
 407     let sr: Box<dyn SampleReader> = match src {
 408             NABufferType::AudioU8(ref ab) => {
 409                 let stride = ab.get_stride();
 410                 let data = ab.get_data();
 411                 if !src_fmt.signed {
 412                     Box::new(GenericSampleReader { data, stride })
 413                 } else {
 414                     Box::new(S8SampleReader { data, stride })
 415                 }
 416             },
 417             NABufferType::AudioI16(ref ab) => {
 418                 let data = ab.get_data();
 419                 let stride = ab.get_stride();
 420                 Box::new(GenericSampleReader { data, stride })
 421             },
 422             NABufferType::AudioI32(ref ab) => {
 423                 let data = ab.get_data();
 424                 let stride = ab.get_stride();
 425                 Box::new(GenericSampleReader { data, stride })
 426             },
 427             NABufferType::AudioF32(ref ab) => {
 428                 let data = ab.get_data();
 429                 let stride = ab.get_stride();
 430                 Box::new(GenericSampleReader { data, stride })
 431             },
 432             NABufferType::AudioPacked(ref ab) => {
 433                 let data = ab.get_data();
 434                 Box::new(PackedSampleReader::new(data, src_fmt))
 435             },
 436             _ => unimplemented!(),
 437         };
 438     let mut sw: Box<dyn SampleWriter> = match dst_buf {
 439             NABufferType::AudioU8(ref mut ab) => {
 440                 let stride = ab.get_stride();
 441                 let data = ab.get_data_mut().unwrap();
 442                 Box::new(GenericSampleWriter { data, stride })
 443             },
 444             NABufferType::AudioI16(ref mut ab) => {
 445                 let stride = ab.get_stride();
 446                 let data = ab.get_data_mut().unwrap();
 447                 Box::new(GenericSampleWriter { data, stride })
 448             },
 449             NABufferType::AudioI32(ref mut ab) => {
 450                 let stride = ab.get_stride();
 451                 let data = ab.get_data_mut().unwrap();
 452                 Box::new(GenericSampleWriter { data, stride })
 453             },
 454             NABufferType::AudioF32(ref mut ab) => {
 455                 let stride = ab.get_stride();
 456                 let data = ab.get_data_mut().unwrap();
 457                 Box::new(GenericSampleWriter { data, stride })
 458             },
 459             NABufferType::AudioPacked(ref mut ab) => {
 460                 let data = ab.get_data_mut().unwrap();
 461                 Box::new(PackedSampleWriter::new(data, dst_fmt))
 462             },
 463             _ => unimplemented!(),
 464         };
 465
 466     let into_float = dst_fmt.float;
 467     if !into_float {
 468         let mut svec = vec![0; src_chmap.num_channels()];
 469         let mut dvec = vec![0; dst_chmap.num_channels()];
 470         let mut spos = 0;
 471         let mut dpos = 0;
 472         for _ in 0..nsamples {
 473             sr.get_samples_i32(spos, &mut svec);
 474             if !channel_op.is_remix() {
 475                 apply_channel_op(&channel_op, &svec, &mut dvec);
 476             } else {
 477                 remix_i32(&channel_op, &svec, &mut dvec);
 478             }
 479             sw.store_samples_i32(dpos, &dvec);
 480             spos += sstep;
 481             dpos += dstep;
 482         }
 483     } else {
 484         let mut svec = vec![0.0; src_chmap.num_channels()];
 485         let mut dvec = vec![0.0; dst_chmap.num_channels()];
 486         let mut spos = 0;
 487         let mut dpos = 0;
 488         for _ in 0..nsamples {
 489             sr.get_samples_f32(spos, &mut svec);
 490             if !channel_op.is_remix() {
 491                 apply_channel_op(&channel_op, &svec, &mut dvec);
 492             } else {
 493                 remix_f32(&channel_op, &svec, &mut dvec);
 494             }
 495             sw.store_samples_f32(dpos, &dvec);
 496             spos += sstep;
 497             dpos += dstep;
 498         }
 499     }
 500     drop(sw);
 501
 502     Ok(dst_buf)
 503 }
 504
 505 /// Checks whether two channel maps are identical.
 506 pub fn channel_maps_equal(a: &NAChannelMap, b: &NAChannelMap) -> bool {
 507     if a.num_channels() != b.num_channels() { return false; }
 508     for i in 0..a.num_channels() {
 509         if a.get_channel(i) != b.get_channel(i) {
 510             return false;
 511         }
 512     }
 513     true
 514 }
 515
 516 /// Checks whether two channel maps have identical channels (but maybe in different order).
 517 pub fn channel_maps_reordered(a: &NAChannelMap, b: &NAChannelMap) -> bool {
 518     if a.num_channels() != b.num_channels() { return false; }
 519     let mut count_a = [0u8; 32];
 520     let mut count_b = [0u8; 32];
 521     for i in 0..a.num_channels() {
 522         count_a[a.get_channel(i) as usize] += 1;
 523         count_b[b.get_channel(i) as usize] += 1;
 524     }
 525     for (c0, c1) in count_a.iter().zip(count_b.iter()) {
 526         if *c0 != *c1 {
 527             return false;
 528         }
 529     }
 530     true
 531 }
 532
 533 /// Calculates permutation matrix for reordering channels from source channel map into destination one.
 534 pub fn calculate_reorder_matrix(src: &NAChannelMap, dst: &NAChannelMap) -> Vec<usize> {
 535     if src.num_channels() != dst.num_channels() { return Vec::new(); }
 536     let num_channels = src.num_channels();
 537     let mut reorder: Vec<usize> = Vec::with_capacity(num_channels);
 538     for i in 0..num_channels {
 539         let dst_ch = dst.get_channel(i);
 540         for j in 0..num_channels {
 541             if src.get_channel(j) == dst_ch {
 542                 reorder.push(j);
 543                 break;
 544             }
 545         }
 546     }
 547     if reorder.len() != num_channels { reorder.clear(); }
 548     reorder
 549 }
 550
 551 fn is_stereo(chmap: &NAChannelMap) -> bool {
 552     (chmap.num_channels() == 2) &&
 553     (chmap.get_channel(0) == NAChannelType::L) &&
 554     (chmap.get_channel(1) == NAChannelType::R)
 555 }
 556
 557 /// Calculates matrix of remixing coefficients for converting input channel layout into destination one.
 558 pub fn calculate_remix_matrix(src: &NAChannelMap, dst: &NAChannelMap) -> Vec<f32> {
 559     if is_stereo(src) && dst.num_channels() == 1 &&
 560         (dst.get_channel(0) == NAChannelType::L || dst.get_channel(0) == NAChannelType::C) {
 561         return vec![0.5, 0.5];
 562     }
 563     if src.num_channels() >= 5 && is_stereo(dst) {
 564         let src_nch = src.num_channels();
 565         let mut mat = vec![0.0f32; src_nch * 2];
 566         let (l_mat, r_mat) = mat.split_at_mut(src_nch);
 567         for ch in 0..src_nch {
 568             match src.get_channel(ch) {
 569                 NAChannelType::L    => l_mat[ch] = 1.0,
 570                 NAChannelType::R    => r_mat[ch] = 1.0,
 571                 NAChannelType::C    => { l_mat[ch] = SQRT_2 / 2.0; r_mat[ch] = SQRT_2 / 2.0; },
 572                 NAChannelType::Ls   => l_mat[ch] = SQRT_2 / 2.0,
 573                 NAChannelType::Rs   => r_mat[ch] = SQRT_2 / 2.0,
 574                 _ => {},
 575             };
 576         }
 577         return mat;
 578     }
 579 unimplemented!();
 580 }
 581
 582 #[cfg(test)]
 583 mod test {
 584     use super::*;
 585     use std::str::FromStr;
 586     use crate::formats::*;
 587
 588     #[test]
 589     fn test_matrices() {
 590         let chcfg51 = NAChannelMap::from_str("L,R,C,LFE,Ls,Rs").unwrap();
 591         let chcfg52 = NAChannelMap::from_str("C,L,R,Ls,Rs,LFE").unwrap();
 592         let stereo  = NAChannelMap::from_str("L,R").unwrap();
 593         let reorder = calculate_reorder_matrix(&chcfg51, &chcfg52);
 594         assert_eq!(reorder.as_slice(), [ 2, 0, 1, 4, 5, 3]);
 595         let remix   = calculate_remix_matrix(&chcfg51, &stereo);
 596         assert_eq!(remix.as_slice(), [ 1.0, 0.0, SQRT_2 / 2.0, 0.0, SQRT_2 / 2.0, 0.0,
 597                                        0.0, 1.0, SQRT_2 / 2.0, 0.0, 0.0, SQRT_2 / 2.0 ]);
 598     }
 599     #[test]
 600     fn test_conversion() {
 601         const CHANNEL_VALUES: [u8; 6] = [ 140, 90, 130, 128, 150, 70 ];
 602         let chcfg51 = NAChannelMap::from_str("L,R,C,LFE,Ls,Rs").unwrap();
 603         let stereo  = NAChannelMap::from_str("L,R").unwrap();
 604         let src_ainfo = NAAudioInfo {
 605                             sample_rate:    44100,
 606                             channels:       chcfg51.num_channels() as u8,
 607                             format:         SND_U8_FORMAT,
 608                             block_len:      512,
 609                         };
 610         let mut dst_ainfo = NAAudioInfo {
 611                             sample_rate:    44100,
 612                             channels:       stereo.num_channels() as u8,
 613                             format:         SND_S16P_FORMAT,
 614                             block_len:      512,
 615                         };
 616         let mut src_frm = alloc_audio_buffer(src_ainfo, 42, chcfg51.clone()).unwrap();
 617         if let NABufferType::AudioU8(ref mut abuf) = src_frm {
 618             let data = abuf.get_data_mut().unwrap();
 619             let mut idx = 0;
 620             for _ in 0..42 {
 621                 for ch in 0..chcfg51.num_channels() {
 622                     data[idx] = CHANNEL_VALUES[ch];
 623                     idx += 1;
 624                 }
 625             }
 626         } else {
 627             panic!("wrong buffer type");
 628         }
 629
 630         let out_frm = convert_audio_frame(&src_frm, &dst_ainfo, &stereo).unwrap();
 631         if let NABufferType::AudioI16(ref abuf) = out_frm {
 632             let off0 = abuf.get_offset(0);
 633             let off1 = abuf.get_offset(1);
 634             let data = abuf.get_data();
 635             let l = data[off0];
 636             let r = data[off1];
 637             assert_eq!(l, 7445);
 638             assert_eq!(r, -19943);
 639         } else {
 640             panic!("wrong buffer type");
 641         }
 642
 643         dst_ainfo.format = SND_F32P_FORMAT;
 644         let out_frm = convert_audio_frame(&src_frm, &dst_ainfo, &stereo).unwrap();
 645         if let NABufferType::AudioF32(ref abuf) = out_frm {
 646             let off0 = abuf.get_offset(0);
 647             let off1 = abuf.get_offset(1);
 648             let data = abuf.get_data();
 649             let l = data[off0];
 650             let r = data[off1];
 651             assert_eq!(l,  0.22633252);
 652             assert_eq!(r, -0.6062342);
 653         } else {
 654             panic!("wrong buffer type");
 655         }
 656     }
 657 }