X-Git-Url: https://git.nihav.org/?p=nihav.git;a=blobdiff_plain;f=nihav-duck%2Fsrc%2Fcodecs%2Fdkadpcm.rs;h=65576e835e28b45059b2f504fe829e2b22653792;hp=e71dd15f1b4303cd512be556c0f0e69e99754239;hb=e781ccc3c7149249c03885e41da02c50faf745bd;hpb=771e522a17b7724a698191ba6f6fe59054161125 diff --git a/nihav-duck/src/codecs/dkadpcm.rs b/nihav-duck/src/codecs/dkadpcm.rs index e71dd15..65576e8 100644 --- a/nihav-duck/src/codecs/dkadpcm.rs +++ b/nihav-duck/src/codecs/dkadpcm.rs @@ -1,35 +1,8 @@ use nihav_core::codecs::*; use nihav_core::io::byteio::*; +use nihav_codec_support::codecs::imaadpcm::*; use std::str::FromStr; -const IMA_MAX_STEP: u8 = 88; -struct IMAState { - predictor: i32, - step: usize, -} - -impl IMAState { - fn new() -> Self { - Self { - predictor: 0, - step: 0, - } - } - fn reset(&mut self, predictor: i16, step: u8) { - self.predictor = i32::from(predictor); - self.step = step.min(IMA_MAX_STEP) as usize; - } - fn expand_sample(&mut self, nibble: u8) -> i16 { - let istep = (self.step as isize) + (IMA_STEPS[nibble as usize] as isize); - let sign = (nibble & 8) != 0; - let diff = (i32::from(2 * (nibble & 7) + 1) * IMA_STEP_TABLE[self.step]) >> 3; - let sample = if !sign { self.predictor + diff } else { self.predictor - diff }; - self.predictor = sample.max(i32::from(std::i16::MIN)).min(i32::from(std::i16::MAX)); - self.step = istep.max(0).min(IMA_MAX_STEP as isize) as usize; - self.predictor as i16 - } -} - struct DuckADPCMDecoder { ainfo: NAAudioInfo, chmap: NAChannelMap, @@ -207,22 +180,3 @@ mod test { ExpectedTestResult::MD5([0x04e40d15, 0xf65b3427, 0x1dd5181f, 0xf321b56f])); } } - -const IMA_STEPS: [i8; 16] = [ - -1, -1, -1, -1, 2, 4, 6, 8, - -1, -1, -1, -1, 2, 4, 6, 8 -]; - -const IMA_STEP_TABLE: [i32; 89] = [ - 7, 8, 9, 10, 11, 12, 13, 14, - 16, 17, 19, 21, 23, 25, 28, 31, - 34, 37, 41, 45, 50, 55, 60, 66, - 73, 80, 88, 97, 107, 118, 130, 143, - 157, 173, 190, 209, 230, 253, 279, 307, - 337, 371, 408, 449, 494, 544, 598, 658, - 724, 796, 876, 963, 1060, 1166, 1282, 1411, - 1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024, - 3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484, - 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899, - 15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767 -];