Intel Music/Audio Coder plus DSP and other bits for it
authorKostya Shishkov <kostya.shishkov@gmail.com>
Tue, 20 Jun 2017 17:02:36 +0000 (19:02 +0200)
committerKostya Shishkov <kostya.shishkov@gmail.com>
Tue, 20 Jun 2017 17:02:36 +0000 (19:02 +0200)
Cargo.toml
src/codecs/indeo/imc.rs [new file with mode: 0644]
src/codecs/indeo/mod.rs
src/codecs/mod.rs
src/dsp/mdct.rs [new file with mode: 0644]
src/dsp/mod.rs
src/dsp/window.rs [new file with mode: 0644]
src/lib.rs

index 91acac66d7c02b52282edc48e3f38433cd84014f..54f5e79bf8e7a7a9c7c53092642ca65a4a8c0010 100644 (file)
@@ -16,6 +16,11 @@ demuxer_gdv = ["demuxers"]
 decoders = []
 h263 = []
 
+dsp = []
+fft = ["dsp"]
+mdct = ["dsp"]
+dsp_window = ["dsp"]
+
 all_decoders = ["all_video_decoders", "all_audio_decoders"]
 
 all_video_decoders = ["decoder_gdvvid", "decoder_indeo2", "decoder_indeo3", "decoder_intel263"]
@@ -24,5 +29,6 @@ decoder_indeo2 = ["decoders"]
 decoder_indeo3 = ["decoders"]
 decoder_intel263 = ["h263", "decoders"]
 
-all_audio_decoders = ["decoder_pcm"]
+all_audio_decoders = ["decoder_pcm", "decoder_imc"]
 decoder_pcm = ["decoders"]
+decoder_imc = ["decoders", "fft", "dsp_window"]
diff --git a/src/codecs/indeo/imc.rs b/src/codecs/indeo/imc.rs
new file mode 100644 (file)
index 0000000..18d24d5
--- /dev/null
@@ -0,0 +1,1162 @@
+use std::mem;
+use std::ptr;
+use std::f32::consts;
+
+use formats::*;
+use frame::*;
+use super::super::*;
+use io::bitreader::*;
+use io::codebook::*;
+use dsp::fft::*;
+use dsp::window::*;
+
+const BANDS:      usize =  32;
+const COEFFS:     usize = 256;
+const BLOCK_SIZE: usize =  64;
+
+fn freq2bark(freq: f32) -> f32 {
+    3.5 * ((freq / 7500.0) * (freq / 7500.0)).atan() + 13.0 * (freq * 0.00076).atan()
+}
+
+struct IMDCTContext {
+    pretwiddle1: [f32; COEFFS/2],
+    pretwiddle2: [f32; COEFFS/2],
+    posttwiddle: [FFTComplex; COEFFS/2],
+    tmp:         [FFTComplex; COEFFS/2],
+    fft:         FFT,
+    window:      [f32; COEFFS],
+}
+
+struct IMCChannel {
+    old_floor:  [f32; BANDS],
+    coeffs1:    [f32; BANDS], // new floor?
+    coeffs2:    [f32; BANDS], // log2 of coeffs1
+    coeffs3:    [f32; BANDS],
+    coeffs4:    [f32; BANDS],
+    coeffs5:    [f32; BANDS],
+    coeffs6:    [f32; BANDS],
+    cw:         [f32; COEFFS],
+    last_im:    [f32; COEFFS/2],
+}
+
+struct BitAlloc {
+    band_width: [usize; BANDS],
+    band_flag:  [bool; BANDS],
+    band_skip:  [bool; BANDS],
+    band_bits:  [u8; BANDS],
+    cw_len:     [u8; COEFFS],
+    band_bitsum: [usize; BANDS],
+    skip_flag:  [bool; COEFFS],
+    skip_flag_bits: [u8; BANDS],
+    skips_per_band: [usize; BANDS],
+    keep_flag:  [bool; BANDS],
+    coeff:      [u8; COEFFS],
+}
+
+impl IMCChannel {
+    fn new() -> Self {
+        IMCChannel {
+            old_floor:  [0.0; BANDS],
+            coeffs1:    [0.0; BANDS],
+            coeffs2:    [0.0; BANDS],
+            coeffs3:    [0.0; BANDS],
+            coeffs4:    [0.0; BANDS],
+            coeffs5:    [0.0; BANDS],
+            coeffs6:    [0.0; BANDS],
+            cw:         [0.0; COEFFS],
+            last_im:    [0.0; COEFFS/2],
+        }
+    }
+    fn reset(&mut self) {
+        for i in 0..self.old_floor.len() { self.old_floor[i] = 1.0; }
+        for i in 0..self.cw.len()        { self.cw[i]        = 0.0; }
+    }
+}
+
+const BITALLOC_LIMIT: f32     = -1.0e20;
+const BITALLOC_TOP_LIMIT: f32 =  1.0e20;
+impl BitAlloc {
+    fn new() -> Self {
+        BitAlloc {
+            band_width:  [0; BANDS],
+            band_flag:   [false; BANDS],
+            band_skip:   [false; BANDS],
+            band_bits:   [0; BANDS],
+            cw_len:      [0; COEFFS],
+            band_bitsum: [0; BANDS],
+            skip_flag:   [false; COEFFS],
+            skip_flag_bits: [0; BANDS],
+            skips_per_band: [0; BANDS],
+            keep_flag:   [false; BANDS],
+            coeff:       [0; COEFFS],
+        }
+    }
+    fn reset(&mut self) {
+        for i in 0..BANDS {
+            self.band_width[i]  = 0;
+            self.band_flag[i]   = false;
+            self.band_skip[i]   = false;
+            self.band_bits[i]   = 0;
+            self.keep_flag[i]   = false;
+            //self.band_bitsum[i] = 0;
+            self.skips_per_band[i] = 0;
+            self.skip_flag_bits[i] = 0;
+        }
+        for i in 0..COEFFS {
+            //self.cw_len[i]      = 0;
+            self.skip_flag[i]   = false;
+        }
+    }
+    fn calculate_bit_allocation(&mut self, ch_data: &mut IMCChannel, bits: usize, fixed_head: bool, adj_idx: usize) -> DecoderResult<()> {
+
+        let mut peak = 0.0;
+        for coef in ch_data.coeffs1.iter() { if *coef > peak { peak = *coef; } }
+        peak *= 0.25;
+
+        for band in 0..BANDS-1 {
+            ch_data.coeffs4[band] = ch_data.coeffs3[band] - ch_data.coeffs5[band].log2();
+        }
+        ch_data.coeffs4[BANDS - 1] = BITALLOC_LIMIT;
+
+        for band in 0..BANDS {
+            let mut idx = 42;
+            let band_w = IMC_BANDS[band + 1] - IMC_BANDS[band];
+            if band_w   == self.band_width[band] { idx = 0; }
+            if band_w   >  self.band_width[band] { idx = 1; }
+            if band_w/2 >= self.band_width[band] { idx = 2; }
+            validate!(idx <= 2);
+            idx *= 2;
+            if ch_data.coeffs1[band] < peak { idx += 1; }
+            ch_data.coeffs4[band] += IMC_BITALLOC_ADJ[adj_idx][idx];
+        }
+
+        if fixed_head {
+            for i in 0..4 {
+                ch_data.coeffs4[i] = BITALLOC_LIMIT;
+            }
+        }
+
+        let start = if fixed_head { 4 } else { 0 };
+
+        let mut a_width = 0;
+        let mut pool = 0.0;
+        for band in start..BANDS-1 {
+            a_width += self.band_width[band];
+            pool    += (self.band_width[band] as f32) * ch_data.coeffs4[band];
+        }
+        validate!(a_width > 0);
+
+        self.band_width[BANDS - 1] = 0;
+        pool = (pool * 0.5 - (bits as f32)) / (a_width as f32);
+
+        let free_bits = bits as i32;
+        let mut cur_bits: i32 = 0;
+        let mut flag = 1;
+        let mut mmcount = 0;
+        for i in 0..BANDS/2 {
+            let diff = cur_bits - free_bits;
+            if diff.abs() <= 8 { break; }
+
+            cur_bits = 0;
+            let mut acc = 0;
+            for band in start..BANDS {
+                let mut len = (ch_data.coeffs4[band] * 0.5 - pool + 0.5).trunc() as i32;
+                if len < 0 { len = 0; }
+                if len > 6 { len = 6; }
+                self.band_bits[band] = len as u8;
+                cur_bits += (self.band_width[band] as i32) * (len as i32);
+                if len > 0 {
+                    acc += self.band_width[band] as i32;
+                }
+            }
+
+            let mut lflag = flag;
+            flag = 1;
+            if free_bits < cur_bits { flag = -1; }
+            if i == 0 { lflag = flag; }
+            if flag != lflag {
+                mmcount += 1;
+            }
+            pool += ((cur_bits - free_bits) as f32) / (((mmcount + 1) * acc) as f32);
+        }
+
+        for band in start..BANDS {
+            for i in IMC_BANDS[band]..IMC_BANDS[band + 1] {
+                self.cw_len[i] = self.band_bits[band];
+            }
+        }
+
+        if free_bits > cur_bits {
+            let mut tmp: [f32; BANDS] = [BITALLOC_LIMIT; BANDS];
+            for band in 0..BANDS {
+                if self.band_bits[band] != 6 {
+                    tmp[band] = (self.band_bits[band] as f32) * -2.0 + ch_data.coeffs4[band] - 0.415;
+                }
+            }
+            let mut peak = 0.0;
+            while (peak > BITALLOC_LIMIT) && (cur_bits < free_bits) {
+                peak = BITALLOC_LIMIT;
+                let mut idx: Option<usize> = None;
+                for band in 0..BANDS {
+                    if tmp[band] > peak {
+                        peak = tmp[band];
+                        idx = Some(band);
+                    }
+                }
+                if let Some(band) = idx {
+                    tmp[band] -= 2.0;
+                    self.band_bits[band] += 1;
+                    if self.band_bits[band] == 6 {
+                        tmp[band] = BITALLOC_LIMIT;
+                    }
+                    for i in IMC_BANDS[band]..IMC_BANDS[band + 1] {
+                        self.cw_len[i] += 1;
+                        cur_bits       += 1;
+                        if cur_bits >= free_bits {
+                            break;
+                        }
+                    }
+                }
+            }
+        }
+
+        if cur_bits > free_bits {
+            let mut tmp: [f32; BANDS] = [BITALLOC_TOP_LIMIT; BANDS];
+            for band in start..BANDS {
+                if self.band_bits[band] != 0 {
+                    tmp[band] = (self.band_bits[band] as f32) * -2.0 + ch_data.coeffs4[band] - 0.415 + 2.0;
+                }
+            }
+            while free_bits < cur_bits {
+                let mut low = BITALLOC_TOP_LIMIT;
+                let mut idx = 0;
+                for band in 0..BANDS {
+                    if tmp[band] < low {
+                        low = tmp[band];
+                        idx = band;
+                    }
+                }
+                tmp[idx] += 2.0;
+                self.band_bits[idx] -= 1;
+                if self.band_bits[idx] == 0 {
+                    tmp[idx] = BITALLOC_TOP_LIMIT;
+                }
+                for i in IMC_BANDS[idx]..IMC_BANDS[idx + 1] {
+                    if self.cw_len[i] > 0 {
+                        self.cw_len[i] -= 1;
+                        cur_bits       -= 1;
+                        if cur_bits <= free_bits {
+                            break;
+                        }
+                    }
+                }
+            }
+        }
+
+        Ok(())
+    }
+
+    fn adjust_bit_allocation(&mut self, ch_data: &mut IMCChannel, free_bits: i32) {
+        let mut tmp: [f32; BANDS] = [BITALLOC_LIMIT; BANDS];
+if free_bits >= 0 {
+        for band in 0..BANDS {
+            if self.band_bits[band] != 6 {
+                tmp[band] = (self.band_bits[band] as f32) * -2.0 + ch_data.coeffs4[band] - 0.415;
+            }
+        }
+        let mut used_bits: i32 = 0;
+        let mut peak = 0.0;
+        while (peak > BITALLOC_LIMIT) && (used_bits < free_bits) {
+            peak = BITALLOC_LIMIT;
+            let mut idx: Option<usize> = None;
+            for band in 0..BANDS {
+                if tmp[band] > peak {
+                    peak = tmp[band];
+                    idx = Some(band);
+                }
+            }
+            if let Some(band) = idx {
+                tmp[band] -= 2.0;
+                self.band_bits[band] += 1;
+                if self.band_bits[band] == 6 {
+                    tmp[band] = BITALLOC_LIMIT;
+                }
+                for i in IMC_BANDS[band]..IMC_BANDS[band + 1] {
+                    self.cw_len[i] += 1;
+                    used_bits      += 1;
+                    if used_bits >= free_bits {
+                        break;
+                    }
+                }
+            }
+        }
+} else {
+        let mut used_bits: i32 = 0;
+
+            let mut tmp: [f32; BANDS] = [BITALLOC_TOP_LIMIT; BANDS];
+            for band in 0..BANDS {
+                if self.band_bits[band] != 0 {
+                    tmp[band] = (self.band_bits[band] as f32) * -2.0 + ch_data.coeffs4[band] - 0.415 + 2.0;
+                }
+            }
+            while free_bits < used_bits {
+                let mut low = BITALLOC_TOP_LIMIT;
+                let mut idx = 0;
+                for band in 0..BANDS {
+                    if tmp[band] < low {
+                        low = tmp[band];
+                        idx = band;
+                    }
+                }
+                tmp[idx] += 2.0;
+                self.band_bits[idx] -= 1;
+                if self.band_bits[idx] == 0 {
+                    tmp[idx] = BITALLOC_TOP_LIMIT;
+                }
+                for i in IMC_BANDS[idx]..IMC_BANDS[idx + 1] {
+                    if self.cw_len[i] > 0 {
+                        self.cw_len[i] -= 1;
+                        used_bits      -= 1;
+                        if used_bits <= free_bits {
+                            break;
+                        }
+                    }
+                }
+            }
+}
+
+    }
+}
+
+struct IMCDecoder {
+    is_imc: bool,
+
+    chmap:  NAChannelMap,
+    ainfo:  NAAudioInfo,
+    info:   Rc<NACodecInfo>,
+
+    codes:  [[Codebook<u8>; 4]; 4],
+    ch_data: [IMCChannel; 2],
+    ba:     BitAlloc,
+    imdct:  IMDCTContext,
+
+    cycle1: [usize; BANDS],
+    cycle2: [usize; BANDS],
+    weights1: [f32; BANDS-1],
+    weights2: [f32; BANDS-1],
+}
+
+fn calc_maxcoef(coef: f32) -> (f32, f32) {
+    let c1 = 20000.0 / 2.0f32.powf(coef * 0.18945);
+    (c1, c1.log2())
+}
+
+impl IMCDecoder {
+    fn new(is_imc: bool) -> Self {
+        let mut codes: [[Codebook<u8>; 4]; 4];
+        let mut cycle1: [usize; BANDS] = [0; BANDS];
+        let mut cycle2: [usize; BANDS] = [0; BANDS];
+        let mut weights1: [f32; BANDS-1] = [0.0; BANDS-1];
+        let mut weights2: [f32; BANDS-1] = [0.0; BANDS-1];
+        if is_imc {
+            cycle1.copy_from_slice(&IMC_CYCLE1);
+            cycle2.copy_from_slice(&IMC_CYCLE2);
+            weights1.copy_from_slice(&IMC_WEIGHTS1);
+            weights2.copy_from_slice(&IMC_WEIGHTS2);
+        }
+        unsafe {
+            codes = mem::uninitialized();
+            for i in 0..4 {
+                for j in 0..4 {
+                    let mut cr = IMCCodeReader::new(i, j);
+                    ptr::write(&mut codes[i][j], Codebook::new(&mut cr, CodebookMode::MSB).unwrap());
+                }
+            }
+        }
+        IMCDecoder {
+            is_imc:     is_imc,
+            chmap:      NAChannelMap::new(),
+            ainfo:      NAAudioInfo::new(0, 0, SND_F32P_FORMAT, 0),
+            info:       NACodecInfo::new_dummy(),
+
+            codes:      codes,
+            ch_data:    [IMCChannel::new(), IMCChannel::new()],
+            ba:         BitAlloc::new(),
+            imdct:      IMDCTContext::new(),
+
+            cycle1:     cycle1,
+            cycle2:     cycle2,
+            weights1:   weights1,
+            weights2:   weights2,
+        }
+    }
+
+    fn generate_iac_tables(&mut self, sample_rate: f32) {
+        let scale = sample_rate / 1024.0;
+        let nyq_freq = sample_rate / 2.0;
+        let mut last_bark = 0.0;
+        let mut freq_max: [f32; BANDS] = [0.0; BANDS];
+        let mut freq_mid: [f32; BANDS] = [0.0; BANDS];
+        let mut freq_min: [f32; BANDS] = [0.0; BANDS];
+        for band in 0..BANDS {
+            let freq = ((IMC_BANDS[band] + IMC_BANDS[band + 1] - 1) as f32) * scale;
+            let bark = freq2bark(freq);
+            if band > 0 {
+                let bark_diff = bark - last_bark;
+                self.weights1[band - 1] = 10.0f32.powf(-1.0 * bark_diff);
+                self.weights1[band - 1] = 10.0f32.powf(-2.7 * bark_diff);
+            }
+            last_bark = bark;
+            freq_mid[band] = freq;
+
+            let mut tmp_freq = freq;
+            while tmp_freq < nyq_freq {
+                tmp_freq += 0.5;
+                if freq2bark(tmp_freq) > bark + 0.5 { break; }
+            }
+            freq_max[band] = tmp_freq;
+
+            let mut tmp_freq = freq;
+            while tmp_freq > 0.0 {
+                tmp_freq -= 0.5;
+                if freq2bark(tmp_freq) < bark - 0.5 { break; }
+            }
+            freq_min[band] = tmp_freq;
+        }
+
+        for band in 0..BANDS {
+            let mut s_band = BANDS - 1;
+            while s_band > 0 && freq_max[band] <= freq_mid[s_band] { s_band -= 1; }
+            self.cycle1[band] = s_band + 1;
+        }
+
+        self.cycle2[0] = 0;
+        for band in 1..BANDS {
+            let mut s_band = 0;
+            while s_band < BANDS-1 && freq_min[band] >= freq_mid[s_band] { s_band += 1; }
+            self.cycle2[band] = s_band - 1;
+        }
+    }
+
+    fn read_level_coeffs_raw(&mut self, br: &mut BitReader, ch: usize) -> DecoderResult<()> {
+        let mut ch_data = &mut self.ch_data[ch];
+        let maxc_pos = br.read(5)? as usize;
+        let max_coef = br.read(7)? as u8;
+
+        let (c1, c2) = calc_maxcoef(max_coef as f32);
+        for i in 0..BANDS {
+            if i != maxc_pos {
+                let level = br.read(4)? as f32;
+                ch_data.coeffs1[i] = c1 * 10.0f32.powf(-level * 0.4375); // almost exp(-lev)
+                ch_data.coeffs2[i] = c2 - 1.4533435415 * level;
+            } else {
+                ch_data.coeffs1[i] = c1;
+                ch_data.coeffs2[i] = c2;
+            }
+            self.ba.band_width[i]  = IMC_BANDS[i + 1] - IMC_BANDS[i];
+            //self.ba.band_flag[i]   = false;
+
+            ch_data.coeffs3[i]     = ch_data.coeffs2[i] * 2.0;
+            ch_data.coeffs5[i]     = 1.0;
+        }
+
+        Ok(())
+    }
+
+    fn calculate_channel_values(&mut self, ch: usize) {
+        let mut ch_data = &mut self.ch_data[ch];
+        let mut tmp2: [f32; BANDS] = [0.0; BANDS];
+        let mut tmp3: [f32; BANDS] = [0.0; BANDS];
+
+        for band in 0..BANDS {
+            ch_data.coeffs5[band] = 0.0;
+            let val;
+            if self.ba.band_width[band] > 0 {
+                val = ch_data.coeffs1[band] * ch_data.coeffs1[band];
+                ch_data.coeffs3[band] = 2.0 * ch_data.coeffs2[band];
+            } else {
+                val = 0.0;
+                ch_data.coeffs3[band] = -30000.0;
+            }
+            tmp3[band] = val * (self.ba.band_width[band] as f32) * 0.01;
+            if tmp3[band] <= 1.0e-6 { tmp3[band] = 0.0; }
+        }
+
+        for band in 0..BANDS {
+            let next_band = self.cycle1[band];
+            for band2 in band..next_band {
+                ch_data.coeffs5[band2] += tmp3[band];
+            }
+            tmp2[next_band - 1] += tmp3[band];
+        }
+
+        let mut accum = 0.0;
+        for band in 0..BANDS-1 {
+            accum = (tmp2[band] + accum) * self.weights1[band];
+            ch_data.coeffs5[band + 1] += accum;
+        }
+
+        let mut tmp2: [f32; BANDS] = [0.0; BANDS];
+        tmp2[0] = tmp3[0];
+        for band in 1..BANDS {
+            let prev_band = self.cycle2[band];
+            for band2 in prev_band+1..band {
+                ch_data.coeffs5[band2] += tmp3[band];
+            }
+            tmp2[prev_band + 1] += tmp3[band];
+        }
+
+        let mut accum = 0.0;
+        for i in 0..BANDS-1 {
+            let band = BANDS - 2 - i;
+            accum = (tmp2[band + 1] + accum) * self.weights2[band];
+            ch_data.coeffs5[band] += accum;
+        }
+    }
+
+    fn read_level_coeffs(&mut self, br: &mut BitReader, reset: bool, sel_idx: usize, ch: usize) -> DecoderResult<()> {
+        let mut level: [i8; BANDS] = [0; BANDS];
+        let start;
+        if reset {
+            start = 1;
+            level[0] = br.read(7)? as i8;
+        } else {
+            start = 0;
+        }
+        for i in start..BANDS {
+            level[i] = br.read_cb(&self.codes[sel_idx][IMC_CB_SELECTOR[sel_idx][i]])? as i8;
+            if level[i] == 17 {
+                level[i] += br.read(4)? as i8;
+            }
+            self.ba.keep_flag[i] = level[i] == 16;
+        }
+        if reset {
+            let mut ch_data = &mut self.ch_data[ch];
+            let (mut c1, mut c2) = calc_maxcoef(level[0] as f32);
+            ch_data.coeffs1[0] = c1;
+            ch_data.coeffs2[0] = c2;
+            for i in 1..BANDS {
+                if level[i] == 16 {
+                    ch_data.coeffs1[i] = 1.0;
+                    ch_data.coeffs2[i] = 0.0;
+                } else {
+                    let lval;
+                    if level[i] < 17 {
+                        lval = (level[i] - 7) as f32;
+                    } else if level[i] < 25 {
+                        lval = (level[i] - 32) as f32;
+                    } else {
+                        lval = (level[i] - 16) as f32;
+                    }
+                    c1 *= 10.0f32.powf(lval * 0.25);
+                    c2 += 0.83048 * lval;
+                    ch_data.coeffs1[i] = c1;
+                    ch_data.coeffs2[i] = c2;
+                }
+            }
+        } else {
+            let mut ch_data = &mut self.ch_data[ch];
+            for i in 0..BANDS {
+                if level[i] < 16 {
+                    let lval = (level[i] - 7) as f32;
+                    ch_data.coeffs1[i]  = 10.0f32.powf(lval * 0.25) * ch_data.old_floor[i];
+                    ch_data.coeffs2[i] += lval * 0.83048;
+                } else {
+                    ch_data.coeffs1[i] = ch_data.old_floor[i];
+                }
+            }
+        }
+
+        for i in 0..BANDS {
+            if level[i] != 16 {
+                self.ba.band_width[i] = IMC_BANDS[i + 1] - IMC_BANDS[i];
+            } else {
+                self.ba.band_width[i] = 0;
+            }
+            //self.ba.band_flag[i]   = false;
+        }
+        
+        for i in 0..BANDS-1 {
+            if self.ba.band_width[i] > 0 {
+                self.ba.band_flag[i] = br.read_bool()?;
+            }
+        }
+        self.calculate_channel_values(ch);
+
+        Ok(())
+    }
+
+    fn read_skip_flags(&mut self, br: &mut BitReader) -> DecoderResult<()> {
+        let mut ba = &mut self.ba;
+        for band in 0..BANDS {
+            if !ba.band_flag[band] || ba.band_width[band] == 0 { continue; }
+
+            if !ba.band_skip[band] {
+                ba.skip_flag_bits[band] = (IMC_BANDS[band + 1] - IMC_BANDS[band]) as u8;
+                for i in IMC_BANDS[band]..IMC_BANDS[band + 1] {
+                    ba.skip_flag[i] = br.read_bool()?;
+                    if ba.skip_flag[i] {
+                        ba.skips_per_band[band] += 1;
+                    }
+                }
+            } else {
+                let mut i = IMC_BANDS[band];
+                while i < IMC_BANDS[band + 1] - 1 {
+                    if !br.read_bool()? {
+                        ba.skip_flag_bits[band] += 1;
+                        ba.skip_flag[i]          = true;
+                        ba.skip_flag[i + 1]      = true;
+                        ba.skips_per_band[band] += 2;
+                    } else {
+                        if br.read_bool()? {
+                            ba.skip_flag_bits[band] += 2;
+                            ba.skip_flag[i]          = false;
+                            ba.skip_flag[i + 1]      = true;
+                            ba.skips_per_band[band] += 1;
+                        } else {
+                            ba.skip_flag_bits[band] += 3;
+                            if !br.read_bool()? {
+                                ba.skip_flag[i]          = true;
+                                ba.skips_per_band[band] += 1;
+                            } else {
+                                ba.skip_flag[i]          = false;
+                            }
+                            ba.skip_flag[i + 1]      = false;
+                        }
+                    }
+                    i += 2;
+                }
+                if i != IMC_BANDS[band + 1] {
+                    ba.skip_flag_bits[band] += 1;
+                    ba.skip_flag[i] = br.read_bool()?;
+                    if ba.skip_flag[i] {
+                        ba.skips_per_band[band] += 1;
+                    }
+                }
+            }
+        }
+        Ok(())
+    }
+
+    fn read_bitalloc_delta(&mut self, br: &mut BitReader, ch: usize) -> DecoderResult<()> {
+        for band in 0..BANDS {
+            self.ba.band_bitsum[band] = 0;
+            self.ba.band_skip[band]   = false;
+            for i in IMC_BANDS[band]..IMC_BANDS[band + 1] {
+                self.ba.band_bitsum[band] += self.ba.cw_len[i] as usize;
+            }
+            if self.ba.band_flag[band] {
+                let band_w = IMC_BANDS[band + 1] - IMC_BANDS[band];
+                let bitsum = self.ba.band_bitsum[band] as usize;
+                if (bitsum > 0) && (band_w * 3 > bitsum * 2) {
+                    self.ba.band_skip[band] = true;
+                }
+            }
+        }
+
+        self.read_skip_flags(br)?;
+
+        let mut ch_data = &mut self.ch_data[ch];
+        for band in 0..BANDS {
+            ch_data.coeffs6[band] = ch_data.coeffs1[band];
+            let band_w = IMC_BANDS[band + 1] - IMC_BANDS[band];
+            let nonskip = band_w - self.ba.skips_per_band[band];
+            if self.ba.band_flag[band] && nonskip > 0 {
+                ch_data.coeffs6[band] *= (band_w as f32).sqrt() / (nonskip as f32).sqrt();
+            }
+        }
+
+        let mut bits_freed: i32 = 0;
+        for band in 0..BANDS {
+            if !self.ba.band_flag[band] { continue; }
+            for i in IMC_BANDS[band]..IMC_BANDS[band + 1] {
+                if self.ba.skip_flag[i] {
+                    bits_freed += self.ba.cw_len[i] as i32;
+                    self.ba.cw_len[i] = 0;
+                }
+            }
+            bits_freed -= self.ba.skip_flag_bits[band] as i32;
+        }
+
+        self.ba.adjust_bit_allocation(&mut ch_data, bits_freed);
+
+        Ok(())
+    }
+
+    fn read_coeffs(&mut self, br: &mut BitReader) -> DecoderResult<()> {
+        for band in 0..BANDS {
+            if self.ba.band_bitsum[band] == 0 { continue; }
+            if !self.ba.band_flag[band] && (self.ba.band_width[band] == 0) { continue; }
+            for i in IMC_BANDS[band]..IMC_BANDS[band + 1] {
+                let len = self.ba.cw_len[i];
+                if len > 0 && (!self.ba.band_flag[band] || !self.ba.skip_flag[i]) {
+                    self.ba.coeff[i] = br.read(len)? as u8;
+                    } else {
+                    self.ba.coeff[i] = 0;
+                }
+            }
+        }
+        Ok(())
+    }
+
+    fn inv_quant(&mut self, ch: usize, raw_coeffs: bool) {
+        let qidx: usize = if raw_coeffs { 1 } else { 0 };
+        let mut ch_data = &mut self.ch_data[ch];
+        for band in 0..BANDS {
+            for i in IMC_BANDS[band]..IMC_BANDS[band + 1] {
+                ch_data.cw[i] = 0.0;
+                let cw_len = self.ba.cw_len[i];
+                if cw_len == 0 || self.ba.skip_flag[i] { continue; }
+
+                let val = self.ba.coeff[i] as usize;
+                let mid = 1 << (cw_len - 1);
+                let max = (1 << cw_len) - 1;
+                if cw_len >= 4 {
+                    let quant = &IMC_QUANT_LARGE[qidx];
+                    if val >= mid {
+                        ch_data.cw[i] =  quant[val - 8]       * ch_data.coeffs6[band];
+                    } else {
+                        ch_data.cw[i] = -quant[max - val - 8] * ch_data.coeffs6[band];
+                    }
+                } else {
+                    let idx = qidx + (if self.ba.band_flag[band] { 2 } else { 0 });
+                    let quant = &IMC_QUANT_SMALL[idx];
+                    if val >= mid {
+                        ch_data.cw[i] =  quant[val - 1]       * ch_data.coeffs6[band];
+                    } else {
+                        ch_data.cw[i] = -quant[max - val - 1] * ch_data.coeffs6[band];
+                    }                    
+                }
+            }
+        }
+    }
+
+    fn decode_block(&mut self, data: &[u8], ch: usize, dst: &mut [f32]) -> DecoderResult<()> {
+        let mut br = BitReader::new(&data[BLOCK_SIZE*ch..], BLOCK_SIZE, BitReaderMode::LE16MSB);
+        let hdr = br.read(9)?;
+        validate!((hdr & 0x18) == 0);
+
+        let reset       = br.read_bool()?;
+        let fixed_head  = br.read_bool()?;
+        let raw_coeffs  = br.read_bool()?;
+        let weight_idx  = br.read(1)? as usize;
+
+        if reset {
+            self.ch_data[ch].reset();
+        }
+
+        self.ba.reset();
+
+        if raw_coeffs {
+            self.read_level_coeffs_raw(&mut br, ch)?;
+        } else {
+            let cb_idx = (if reset { 2 } else { 0 }) + (if fixed_head { 1 } else { 0 });
+            self.read_level_coeffs(&mut br, reset, cb_idx, ch)?;
+        }
+
+        self.ch_data[ch].old_floor.copy_from_slice(&self.ch_data[ch].coeffs1);
+
+        let mut bitcount: usize = 0;
+        if fixed_head {
+            bitcount += 15;
+            self.ba.band_bits[0] = 5;
+            for i in 0..3 {
+                self.ba.cw_len[i] = 5;
+            }
+            for band in 1..4 {
+                let bits: u8;
+                if raw_coeffs || !self.ba.keep_flag[band]{
+                    bits = 5;
+                } else {
+                    bits = 0;
+                }
+                self.ba.band_bits[band] = bits;
+                for i in IMC_BANDS[band]..IMC_BANDS[band + 1] {
+                    self.ba.cw_len[i] = bits;
+                    bitcount += bits as usize;
+                }
+            }
+        }
+
+        if !self.is_imc {
+            if self.ba.band_width[BANDS - 1] != 0 {
+                bitcount += 1;
+            }
+            if !fixed_head {
+                bitcount += 16;
+            }
+        }
+
+        validate!(br.tell() + bitcount < BLOCK_SIZE * 8);
+        self.ba.calculate_bit_allocation(&mut self.ch_data[ch], 512 - bitcount - br.tell(), fixed_head, weight_idx)?;
+
+        if !raw_coeffs {
+            self.read_bitalloc_delta(&mut br, ch)?;
+        }
+
+        for band in 0..BANDS {
+            self.ba.band_bitsum[band] = 0;
+            for i in IMC_BANDS[band]..IMC_BANDS[band + 1] {
+                if !self.ba.skip_flag[i] {
+                    self.ba.band_bitsum[band] += self.ba.cw_len[i] as usize;
+                }
+            }
+        }
+
+        self.read_coeffs(&mut br)?;
+        self.inv_quant(ch, raw_coeffs);
+        self.imdct.imdct(&self.ch_data[ch].cw, dst, &mut self.ch_data[ch].last_im);
+
+        Ok(())
+    }
+}
+
+impl IMDCTContext {
+    fn new() -> Self {
+        let mut window: [f32; COEFFS] = [0.0; COEFFS];
+        generate_window(WindowType::Sine, 1.0, COEFFS, true, &mut window);
+        let mut pretwiddle1: [f32; COEFFS/2] = [0.0; COEFFS/2];
+        let mut pretwiddle2: [f32; COEFFS/2] = [0.0; COEFFS/2];
+        let mut posttwiddle: [FFTComplex; COEFFS/2] = [FFTC_ZERO; COEFFS/2];
+        for i in 0..COEFFS/2 {
+            let n = i as f32;
+            let base = (n * 4.0 + 1.0) / 1024.0 * consts::PI;
+            let r1 = base.sin();
+            let r2 = base.cos();
+            if (i & 1) == 0 {
+                pretwiddle1[i] = -(r1 + r2) * consts::SQRT_2;
+                pretwiddle2[i] =  (r1 - r2) * consts::SQRT_2;
+            } else {
+                pretwiddle1[i] =  (r1 + r2) * consts::SQRT_2;
+                pretwiddle2[i] = -(r1 - r2) * consts::SQRT_2;
+            }
+            posttwiddle[i] = FFTComplex::exp(consts::PI / 256.0 * n).scale(1.0/32768.0);
+        }
+        IMDCTContext {
+            pretwiddle1: pretwiddle1,
+            pretwiddle2: pretwiddle2,
+            posttwiddle: posttwiddle,
+            tmp:         [FFTC_ZERO; COEFFS/2],
+            fft:         FFTBuilder::new_fft(FFTMode::SplitRadix, COEFFS/2),
+            window:      window,
+        }
+    }
+    fn imdct(&mut self, coeffs: &[f32; COEFFS], dst: &mut [f32], last_im: &mut [f32; COEFFS/2]) {
+        for i in 0..COEFFS/2 {
+            let in2 = coeffs[i * 2];
+            let in1 = coeffs[COEFFS - 1 - i * 2];
+            let c2  = self.pretwiddle1[i];
+            let c1  = self.pretwiddle2[i];
+            self.tmp[i].re = -(c2 * in1 + c1 * in2);
+            self.tmp[i].im =   c1 * in1 - c2 * in2;
+        }
+        self.fft.do_fft_inplace(&mut self.tmp, false);
+        for i in 0..COEFFS/2 {
+            let tmp = !(self.tmp[i] * self.posttwiddle[i]);
+            let c1 = self.window[i * 2];
+            let c2 = self.window[COEFFS - 1 - i * 2];
+            let im = last_im[i];
+            dst[i * 2]              = c2 * im + c1 * tmp.re;
+            dst[COEFFS - 1 - i * 2] = c1 * im - c2 * tmp.re;
+            last_im[i] = tmp.im;
+        }
+    }
+}
+
+const CHMAP_MONO: [NAChannelType; 1] = [NAChannelType::C];
+const CHMAP_STEREO: [NAChannelType; 2] = [NAChannelType::L, NAChannelType::R];
+
+impl NADecoder for IMCDecoder {
+    fn init(&mut self, info: Rc<NACodecInfo>) -> DecoderResult<()> {
+        if let NACodecTypeInfo::Audio(ainfo) = info.get_properties() {
+            self.chmap = NAChannelMap::new();
+            match ainfo.get_channels() {
+                1 => { self.chmap.add_channels(&CHMAP_MONO); },
+                2 => { self.chmap.add_channels(&CHMAP_STEREO); },
+                _ => { return Err(DecoderError::InvalidData); },
+            };
+            self.ainfo = NAAudioInfo::new(ainfo.get_sample_rate(),
+                                          ainfo.get_channels(),
+                                          SND_F32P_FORMAT, 0);
+            self.info = info.replace_info(NACodecTypeInfo::Audio(self.ainfo.clone()));
+
+            if !self.is_imc {
+                self.generate_iac_tables(ainfo.get_sample_rate() as f32);
+            }
+            Ok(())
+        } else {
+            Err(DecoderError::InvalidData)
+        }
+    }
+    fn decode(&mut self, pkt: &NAPacket) -> DecoderResult<NAFrameRef> {
+        let info = pkt.get_stream().get_info();
+        validate!(info.get_properties().is_audio());
+        let pktbuf = pkt.get_buffer();
+
+        let nblocks = pktbuf.len() / BLOCK_SIZE / (self.ainfo.get_channels() as usize);
+        let duration = COEFFS * nblocks;
+
+        let mut abuf = alloc_audio_buffer(self.ainfo, duration, self.chmap.clone())?;
+        let mut adata = abuf.get_abuf_f32().unwrap();
+        let mut dst = adata.get_data_mut();
+
+        let mut start: usize = 0;
+        for chunk in pktbuf.chunks(BLOCK_SIZE * (self.ainfo.get_channels() as usize)) {
+            for ch in 0..self.ainfo.get_channels() {
+                let off = abuf.get_offset(ch as usize) + start;
+                self.decode_block(chunk, ch as usize, &mut dst[off..off+COEFFS])?;
+            }
+            start += COEFFS;
+        }
+
+        let mut frm = NAFrame::new_from_pkt(pkt, self.info.clone(), abuf);
+        frm.set_keyframe(true);
+        Ok(Rc::new(RefCell::new(frm)))
+    }
+}
+
+pub fn get_decoder_imc() -> Box<NADecoder> {
+    Box::new(IMCDecoder::new(true))
+}
+
+pub fn get_decoder_iac() -> Box<NADecoder> {
+    Box::new(IMCDecoder::new(false))
+}
+
+struct IMCCodeReader { sel1: usize, sel2: usize }
+
+impl IMCCodeReader {
+    fn new(sel1: usize, sel2: usize) -> Self { IMCCodeReader { sel1: sel1, sel2: sel2 } }
+}
+
+impl CodebookDescReader<u8> for IMCCodeReader {
+    fn bits(&mut self, idx: usize) -> u8  { IMC_CODE_LENGTHS[self.sel1][self.sel2][idx] }
+    fn code(&mut self, idx: usize) -> u32 { IMC_CODE_CODES[self.sel1][self.sel2][idx] as u32 }
+    fn sym (&mut self, idx: usize) -> u8 { idx as u8 }
+    fn len(&mut self) -> usize { IMC_CODE_LENGTHS[0][0].len() }
+}
+
+static IMC_BANDS: [usize; 33] = [
+      0,   3,   6,   9,  12,  16,  20,  24,  29,  34,  40,  46,  53,  60,  68,  76,
+     84,  93, 102, 111, 121, 131, 141, 151, 162, 173, 184, 195, 207, 219, 231, 243,
+    256,
+];
+
+const IMC_QUANT_SMALL: &[[f32; 8]; 4] = &[
+    [ 8.4431201e-1, 4.7358301e-1, 1.448354,  2.7073899e-1,
+      7.4449003e-1, 1.241991,     1.845484,  0.0 ],
+    [ 8.6876702e-1, 4.7659001e-1, 1.478224,  2.5672799e-1,
+      7.55777e-1,   1.3229851,    2.03438,   0.0 ],
+    [ 7.5891501e-1, 6.2272799e-1, 1.271322,  3.47904e-1,
+      7.5317699e-1, 1.150767,     1.628476,  0.0 ],
+    [ 7.65257e-1,   6.44647e-1,   1.263824,  3.4548101e-1,
+      7.6384902e-1, 1.214466,     1.7638789, 0.0 ]
+];
+
+const IMC_QUANT_LARGE: &[[f32; 56]; 2] = &[
+    [ 1.39236e-1,   3.50548e-1,   5.9547901e-1, 8.5772401e-1,
+      1.121545,     1.3882281,    1.695882,     2.1270809,
+      7.2221003e-2, 1.85177e-1,   2.9521701e-1, 4.12568e-1,
+      5.4068601e-1, 6.7679501e-1, 8.1196898e-1, 9.4765198e-1,
+      1.0779999,    1.203415,     1.337265,     1.481871,
+      1.639982,     1.814766,     2.0701399,    2.449862,
+      3.7533998e-2, 1.02722e-1,   1.6021401e-1, 2.16043e-1,
+      2.7231601e-1, 3.3025399e-1, 3.9022601e-1, 4.52849e-1,
+      5.1794899e-1, 5.8529502e-1, 6.53956e-1,   7.2312802e-1,
+      7.9150802e-1, 8.5891002e-1, 9.28141e-1,   9.9706203e-1,
+      1.062153,     1.12564,      1.189834,     1.256122,
+      1.324469,     1.3955311,    1.468906,     1.545084,
+      1.6264729,    1.711524,     1.802705,     1.91023,
+      2.0533991,    2.22333,      2.4830019,    3.253329 ],
+    [ 1.11654e-1,   3.54469e-1,   6.4232099e-1, 9.6128798e-1,
+      1.295053,     1.61777,      1.989839,     2.51107,
+      5.7721999e-2, 1.69879e-1,   2.97589e-1,   4.3858799e-1,
+      5.9039903e-1, 7.4934798e-1, 9.1628098e-1, 1.087297,
+      1.262751,     1.4288321,    1.6040879,    1.79067,
+      2.000668,     2.2394669,    2.649332,     5.2760072,
+      2.9722e-2,    8.7316997e-2, 1.4445201e-1, 2.04247e-1,
+      2.6879501e-1, 3.3716801e-1, 4.08811e-1,   4.8306999e-1,
+      5.6049401e-1, 6.3955498e-1, 7.2044599e-1, 8.0427998e-1,
+      8.8933599e-1, 9.7537601e-1, 1.062461,     1.1510431,
+      1.240236,     1.326715,     1.412513,     1.500502,
+      1.591749,     1.686413,     1.785239,     1.891233,
+      2.0051291,    2.127681,     2.2709141,    2.475826,
+      2.7219379,    3.101985,     4.686213,     6.2287788 ]
+];
+
+static IMC_CYCLE1: [usize; BANDS] = [
+     1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16,
+    17, 18, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 32,
+];
+
+static IMC_CYCLE2: [usize; BANDS] = [
+     0,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,
+    15, 16, 17, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29
+];
+
+static IMC_WEIGHTS1: [f32; BANDS-1] = [
+    0.119595,   0.123124,   0.129192,   9.97377e-2,
+    8.1923e-2,  9.61153e-2, 8.77885e-2, 8.61174e-2,
+    9.00882e-2, 9.91658e-2, 0.112991,   0.131126,
+    0.152886,   0.177292,   0.221782,   0.244917,
+    0.267386,   0.306816,   0.323046,   0.33729,
+    0.366773,   0.392557,   0.398076,   0.403302,
+    0.42451,    0.444777,   0.449188,   0.455445,
+    0.477853,   0.500669,   0.510395
+];
+
+static IMC_WEIGHTS2: [f32; BANDS-1] = [
+    3.23466e-3, 3.49886e-3, 3.98413e-3, 1.98116e-3,
+    1.16465e-3, 1.79283e-3, 1.40372e-3, 1.33274e-3,
+    1.50523e-3, 1.95064e-3, 2.77472e-3, 4.14725e-3,
+    6.2776e-3,  9.36401e-3, 1.71397e-2, 2.24052e-2,
+    2.83971e-2, 4.11689e-2, 4.73165e-2, 5.31631e-2,
+    6.66614e-2, 8.00824e-2, 8.31588e-2, 8.61397e-2,
+    9.89229e-2, 0.112197,   0.115227,   0.119613,
+    0.136174,   0.15445,    0.162685
+];
+
+static IMC_BITALLOC_ADJ: [[f32; 7]; 2] = [
+    [ 7.6, 4.4, 6.1, 2.3, 6.2, 1.8, 0.0 ],
+    [ 3.6, 3.7, 5.1, 1.6, 1.5, 1.2, 0.0 ]
+];
+
+static IMC_CODE_LENGTHS: &[[[u8; 18]; 4]; 4] = &[
+    [
+        [ 16, 15, 13, 11,  8,  5,  3,  1,  2,  4,  6,  9, 10, 12, 14, 16,  7,  0 ],
+        [ 10,  8,  7,  6,  4,  4,  3,  2,  2,  3,  4,  6,  7,  9, 11, 11,  7,  0 ],
+        [ 15, 15, 14, 11,  8,  6,  4,  2,  1,  4,  5,  7,  9, 10, 12, 13,  4,  0 ],
+        [ 13, 11, 10,  8,  6,  4,  2,  2,  2,  3,  5,  7,  9, 12, 15, 15, 14,  0 ],
+    ], [
+        [ 14, 12, 10,  8,  7,  4,  2,  2,  2,  3,  5,  7,  9, 11, 13, 14,  7,  0 ],
+        [ 14, 13, 11,  8,  6,  4,  3,  2,  2,  3,  5,  7,  9, 10, 12, 14,  3,  0 ],
+        [ 13, 12, 10,  7,  5,  4,  3,  2,  2,  3,  4,  6,  8,  9, 11, 13,  4,  0 ],
+        [ 13, 12, 10,  7,  5,  4,  3,  2,  2,  3,  4,  6,  8,  9, 11, 13,  4,  0 ],
+    ], [
+        [ 16, 14, 12, 10,  8,  5,  3,  1,  2,  4,  7,  9, 11, 13, 15, 17,  6, 17 ],
+        [ 15, 13, 11,  8,  6,  4,  2,  2,  2,  3,  5,  7, 10, 12, 14, 16,  9, 16 ],
+        [ 14, 12, 11,  9,  8,  6,  3,  1,  2,  5,  7, 10, 13, 15, 16, 17,  4, 17 ],
+        [ 16, 14, 12,  9,  7,  5,  2,  2,  2,  3,  4,  6,  8, 11, 13, 15, 10, 16 ],
+    ], [
+        [ 13, 11, 10,  8,  7,  5,  2,  2,  2,  4,  6,  9, 12, 14, 15, 16,  3, 16 ],
+        [ 11, 11, 10,  9,  8,  7,  5,  4,  3,  3,  3,  3,  3,  3,  4,  5,  6,  5 ],
+        [  9,  9,  7,  6,  5,  4,  3,  3,  2,  3,  4,  5,  4,  5,  5,  6,  8,  6 ],
+        [ 13, 12, 10,  8,  5,  3,  3,  2,  2,  3,  4,  7,  9, 11, 14, 15,  6, 15 ]
+    ]
+];
+
+static IMC_CODE_CODES: &[[[u16; 18]; 4]; 4] = &[
+    [
+        [ 0xCC32, 0x6618, 0x1987, 0x0660, 0x00CD, 0x0018, 0x0007, 0x0000, 0x0002,
+          0x000D, 0x0032, 0x0199, 0x0331, 0x0CC2, 0x330D, 0xCC33, 0x0067, 0x0000 ],
+        [ 0x02FE, 0x00BE, 0x005E, 0x002D, 0x000A, 0x0009, 0x0003, 0x0003, 0x0000,
+          0x0002, 0x0008, 0x002C, 0x005D, 0x017E, 0x05FE, 0x05FF, 0x005C, 0x0000 ],
+        [ 0x5169, 0x5168, 0x28B5, 0x0517, 0x00A3, 0x0029, 0x0008, 0x0003, 0x0000,
+          0x0009, 0x0015, 0x0050, 0x0144, 0x028A, 0x0A2C, 0x145B, 0x000B, 0x0000 ],
+        [ 0x1231, 0x048D, 0x0247, 0x0090, 0x0025, 0x0008, 0x0001, 0x0003, 0x0000,
+          0x0005, 0x0013, 0x0049, 0x0122, 0x0919, 0x48C3, 0x48C2, 0x2460, 0x0000 ]
+    ], [
+        [ 0x2D1D, 0x0B46, 0x02D0, 0x00B5, 0x0059, 0x000A, 0x0003, 0x0001, 0x0000,
+          0x0004, 0x0017, 0x005B, 0x0169, 0x05A2, 0x168F, 0x2D1C, 0x0058, 0x0000 ],
+        [ 0x1800, 0x0C01, 0x0301, 0x0061, 0x0019, 0x0007, 0x0004, 0x0003, 0x0000,
+          0x0005, 0x000D, 0x0031, 0x00C1, 0x0181, 0x0601, 0x1801, 0x0002, 0x0000 ],
+        [ 0x1556, 0x0AAA, 0x02AB, 0x0054, 0x0014, 0x000B, 0x0002, 0x0003, 0x0000,
+          0x0003, 0x0008, 0x002B, 0x00AB, 0x0154, 0x0554, 0x1557, 0x0009, 0x0000 ],
+        [ 0x1556, 0x0AAA, 0x02AB, 0x0054, 0x0014, 0x000B, 0x0002, 0x0003, 0x0000,
+          0x0003, 0x0008, 0x002B, 0x00AB, 0x0154, 0x0554, 0x1557, 0x0009, 0x0000 ]
+    ], [
+        [ 0x2993, 0x0A65, 0x0298, 0x00A7, 0x0028, 0x0004, 0x0000, 0x0001, 0x0001,
+          0x0003, 0x0015, 0x0052, 0x014D, 0x0533, 0x14C8, 0x5324, 0x000B, 0x5325 ],
+        [ 0x09B8, 0x026F, 0x009A, 0x0012, 0x0005, 0x0000, 0x0001, 0x0002, 0x0003,
+          0x0001, 0x0003, 0x0008, 0x004C, 0x0136, 0x04DD, 0x1373, 0x0027, 0x1372 ],
+        [ 0x0787, 0x01E0, 0x00F1, 0x003D, 0x001F, 0x0006, 0x0001, 0x0001, 0x0001,
+          0x0002, 0x000E, 0x0079, 0x03C2, 0x0F0D, 0x1E19, 0x3C30, 0x0000, 0x3C31 ],
+        [ 0x4B06, 0x12C0, 0x04B1, 0x0097, 0x0024, 0x0008, 0x0002, 0x0003, 0x0000,
+          0x0003, 0x0005, 0x0013, 0x004A, 0x0259, 0x0961, 0x2582, 0x012D, 0x4B07 ]
+    ], [
+        [ 0x0A5A, 0x0297, 0x014A, 0x0053, 0x0028, 0x000B, 0x0003, 0x0000, 0x0002,
+          0x0004, 0x0015, 0x00A4, 0x052C, 0x14B7, 0x296C, 0x52DB, 0x0003, 0x52DA ],
+        [ 0x0193, 0x0192, 0x00C8, 0x0065, 0x0033, 0x0018, 0x0007, 0x0004, 0x0000,
+          0x0004, 0x0005, 0x0007, 0x0006, 0x0003, 0x0005, 0x0005, 0x000D, 0x0004 ],
+        [ 0x0012, 0x0013, 0x0005, 0x0003, 0x0000, 0x0003, 0x0005, 0x0004, 0x0003,
+          0x0003, 0x0005, 0x0005, 0x0004, 0x0004, 0x0003, 0x0005, 0x0008, 0x0004 ],
+        [ 0x0D66, 0x06B2, 0x01AD, 0x006A, 0x000C, 0x0005, 0x0004, 0x0000, 0x0003,
+          0x0002, 0x0007, 0x0034, 0x00D7, 0x0358, 0x1ACF, 0x359C, 0x001B, 0x359D ]
+    ]
+];
+
+const IMC_CB_SELECTOR: [[usize; BANDS]; 4] = [
+    [ 1, 1, 1, 1, 1, 1, 3, 3, 3, 3, 3, 3, 3, 3, 0, 0,
+      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2 ],
+    [ 0, 2, 0, 3, 2, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+      0, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 ],
+    [ 1, 1, 1, 1, 1, 1, 1, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+      3, 3, 3, 3, 3, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2 ],
+    [ 0, 1, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+      3, 3, 3, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ]
+];
+
+#[cfg(test)]
+mod test {
+    use codecs::*;
+    use demuxers::*;
+    use io::byteio::*;
+    use test::wavwriter::WavWriter;
+
+    #[test]
+    fn test_imc() {
+        let avi_dmx = find_demuxer("avi").unwrap();
+        let mut file = File::open("assets/neal73_saber.avi").unwrap();
+        let mut fr = FileReader::new_read(&mut file);
+        let mut br = ByteReader::new(&mut fr);
+        let mut dmx = avi_dmx.new_demuxer(&mut br);
+        dmx.open().unwrap();
+
+        let mut file = File::create("assets/imc-out.wav").unwrap();
+        let mut fw = FileWriter::new_write(&mut file);
+        let mut wr = ByteWriter::new(&mut fw);
+        let mut wwr = WavWriter::new(&mut wr);
+        let mut wrote_header = false;
+
+        let mut decs: Vec<Option<Box<NADecoder>>> = Vec::new();
+        for i in 0..dmx.get_num_streams() {
+            let s = dmx.get_stream(i).unwrap();
+            let info = s.get_info();
+            let decfunc = find_decoder(info.get_name());
+            if let Some(df) = decfunc {
+                if info.is_audio() {
+                    let mut dec = (df)();
+                    dec.init(info).unwrap();
+                    decs.push(Some(dec));
+                } else {
+                    decs.push(None);
+                }
+            } else {
+                decs.push(None);
+            }
+        }
+
+        loop {
+            let pktres = dmx.get_frame();
+            if let Err(e) = pktres {
+                if e == DemuxerError::EOF { break; }
+                panic!("error");
+            }
+            let pkt = pktres.unwrap();
+            //if pkt.get_pts().unwrap() > 10 { break; }
+            let streamno = pkt.get_stream().get_id() as usize;
+            if let Some(ref mut dec) = decs[streamno] {
+                let frm_ = dec.decode(&pkt).unwrap();
+                let frm = frm_.borrow();
+                if frm.get_info().is_audio() {
+                    if !wrote_header {
+                        wwr.write_header(frm.get_info().as_ref().get_properties().get_audio_info().unwrap()).unwrap();
+                        wrote_header = true;
+                    }
+                    wwr.write_frame(frm.get_buffer()).unwrap();
+                }
+            }
+        }
+panic!("the end");
+    }
+}
index c019f47975b69704093775ea1dde10d1094c9732..43da6ed0affdcf686f1bc87f985167e8c88e8bc9 100644 (file)
@@ -3,3 +3,6 @@ pub mod indeo2;
 #[cfg(feature="decoder_indeo3")]
 pub mod indeo3;
 
+#[cfg(feature="decoder_imc")]
+pub mod imc;
+
index 4978124428de93db5bdaa04fa5b0e7711c56eecf..cdbc06bcf3a2da6e15322dd0edb05ea493fe20bd 100644 (file)
@@ -9,6 +9,7 @@ use io::codebook::CodebookError;
 #[allow(dead_code)]
 pub enum DecoderError {
     NoFrame,
+    AllocError,
     TryAgain,
     InvalidData,
     ShortData,
@@ -36,6 +37,10 @@ impl From<CodebookError> for DecoderError {
     fn from(_: CodebookError) -> Self { DecoderError::InvalidData }
 }
 
+impl From<AllocatorError> for DecoderError {
+    fn from(_: AllocatorError) -> Self { DecoderError::AllocError }
+}
+
 macro_rules! validate {
     ($a:expr) => { if !$a { return Err(DecoderError::InvalidData); } };
 }
@@ -113,7 +118,7 @@ mod blockdsp;
 
 #[cfg(feature="decoder_gdvvid")]
 mod gremlinvideo;
-#[cfg(any(feature="decoder_indeo2", feature="decoder_indeo3"))]
+#[cfg(any(feature="decoder_indeo2", feature="decoder_indeo3", feature="decoder_imc"))]
 mod indeo;
 #[cfg(feature="h263")]
 mod h263;
@@ -133,6 +138,10 @@ const DECODERS: &[DecoderInfo] = &[
 
 #[cfg(feature="decoder_pcm")]
     DecoderInfo { name: "pcm", get_decoder: pcm::get_decoder },
+#[cfg(feature="decoder_imc")]
+    DecoderInfo { name: "imc", get_decoder: indeo::imc::get_decoder_imc },
+#[cfg(feature="decoder_imc")]
+    DecoderInfo { name: "iac", get_decoder: indeo::imc::get_decoder_iac },
 ];
 
 pub fn find_decoder(name: &str) -> Option<fn () -> Box<NADecoder>> {
diff --git a/src/dsp/mdct.rs b/src/dsp/mdct.rs
new file mode 100644 (file)
index 0000000..e69de29
index 14b7cbebdb283b81ac2f448fb3a4123763eff4db..439ad98851ca2c8acde373d88b9262081df1f584 100644 (file)
@@ -1 +1,6 @@
+#[cfg(feature="fft")]
 pub mod fft;
+#[cfg(feature="mdct")]
+pub mod mdct;
+#[cfg(feature="dsp_window")]
+pub mod window;
diff --git a/src/dsp/window.rs b/src/dsp/window.rs
new file mode 100644 (file)
index 0000000..d59a005
--- /dev/null
@@ -0,0 +1,30 @@
+use std::f32::consts;
+
+#[derive(Debug,Clone,Copy,PartialEq)]
+pub enum WindowType {
+    Square,
+    Sine,
+    KaiserBessel,
+}
+
+pub fn generate_window(mode: WindowType, scale: f32, size: usize, half: bool, dst: &mut [f32]) {
+    match mode {
+        WindowType::Square => {
+                for n in 0..size { dst[n] = scale; }
+            },
+        WindowType::Sine => {
+                let param;
+                if half {
+                    param = consts::PI / ((2 * size) as f32);
+                } else {
+                    param = consts::PI / (size as f32);
+                }
+                for n in 0..size {
+                    dst[n] = (((n as f32) + 0.5) * param).sin() * scale;
+                }
+            },
+        WindowType::KaiserBessel => {
+unimplemented!();
+            },
+    };
+}
index c0ae9758579c5cc08aaa5a3a14b88b8006fa7a16..07c451e150004a94aa83212da02cceaa7331682c 100644 (file)
@@ -10,6 +10,7 @@ pub mod io;
 pub mod register;
 pub mod detect;
 
+#[cfg(feature="dsp")]
 pub mod dsp;
 
 #[cfg(test)]