diff options
Diffstat (limited to 'src/client/kotlin')
14 files changed, 862 insertions, 8 deletions
diff --git a/src/client/kotlin/space/autistic/radio/client/antenna/AntennaModel.kt b/src/client/kotlin/space/autistic/radio/client/antenna/AntennaModel.kt index 74a7c96..c1f3e13 100644 --- a/src/client/kotlin/space/autistic/radio/client/antenna/AntennaModel.kt +++ b/src/client/kotlin/space/autistic/radio/client/antenna/AntennaModel.kt @@ -5,15 +5,15 @@ import org.joml.Vector3d interface AntennaModel { /** * Returns the linear power level/gain to apply for a receiver at the given position. The receiver is assumed to be - * vertically oriented. + * vertically oriented. The gain should scale with distance, as appropriate. * * Note: 1.0f = 0dB, 0.5f = -3dB (approx.), 0.1f = -10dB. */ fun apply(position: Vector3d): Float /** - * Returns whether to process block/material attenuation. Useful for "global" antennas (i.e. those that return a - * constant for all positions given to [apply]). + * Returns whether to process block/material attenuation. Useful (when false) for "global" antennas (i.e. those that + * return a constant for all positions given to [apply]). */ fun shouldAttenuate(): Boolean } \ No newline at end of file diff --git a/src/client/kotlin/space/autistic/radio/client/antenna/NullModel.kt b/src/client/kotlin/space/autistic/radio/client/antenna/ConstAntennaModel.kt index 3c188b6..fc531d2 100644 --- a/src/client/kotlin/space/autistic/radio/client/antenna/NullModel.kt +++ b/src/client/kotlin/space/autistic/radio/client/antenna/ConstAntennaModel.kt @@ -2,9 +2,9 @@ package space.autistic.radio.client.antenna import org.joml.Vector3d -class NullModel : AntennaModel { +class ConstAntennaModel(private val level: Float) : AntennaModel { override fun apply(position: Vector3d): Float { - return 0f + return level } override fun shouldAttenuate(): Boolean { diff --git a/src/client/kotlin/space/autistic/radio/client/antenna/WasmAntennaFactory.kt b/src/client/kotlin/space/autistic/radio/client/antenna/WasmAntennaFactory.kt index 7181e95..51743dd 100644 --- a/src/client/kotlin/space/autistic/radio/client/antenna/WasmAntennaFactory.kt +++ b/src/client/kotlin/space/autistic/radio/client/antenna/WasmAntennaFactory.kt @@ -33,7 +33,7 @@ class WasmAntennaFactory(moduleBytes: ByteArray) : AntennaModelFactory { override fun create(orientation: Quaterniond): AntennaModel { if (failing) { - return NullModel() + return ConstAntennaModel(0f) } try { val instance = instanceBuilder!!.build() @@ -57,7 +57,7 @@ class WasmAntennaFactory(moduleBytes: ByteArray) : AntennaModelFactory { Level.SEVERE, "Error while trying to initialize antenna model: missing 'should-attenuate'" ) failing = true - return NullModel() + return ConstAntennaModel(0f) } val shouldAttenuate = instance.exports().global("should-attenuate").value != 0L val apply = instance.export("apply") @@ -86,7 +86,7 @@ class WasmAntennaFactory(moduleBytes: ByteArray) : AntennaModelFactory { } catch (e: ChicoryException) { logger.log(Level.SEVERE, "Error while trying to initialize antenna model.", e) failing = true - return NullModel() + return ConstAntennaModel(0f) } } diff --git a/src/client/kotlin/space/autistic/radio/client/cli/OfflineSimulator.kt b/src/client/kotlin/space/autistic/radio/client/cli/OfflineSimulator.kt new file mode 100644 index 0000000..68c4719 --- /dev/null +++ b/src/client/kotlin/space/autistic/radio/client/cli/OfflineSimulator.kt @@ -0,0 +1,237 @@ +package space.autistic.radio.client.cli + +import org.joml.Vector2f +import space.autistic.radio.client.complex.cmul +import space.autistic.radio.client.fmsim.FmFullConstants +import space.autistic.radio.client.fmsim.FmFullDemodulator +import space.autistic.radio.client.fmsim.FmFullModulator +import java.io.FileInputStream +import java.io.FileOutputStream +import java.io.InputStream +import java.net.URI +import java.nio.ByteBuffer +import java.nio.ByteOrder +import java.nio.FloatBuffer +import kotlin.io.path.inputStream +import kotlin.io.path.toPath +import kotlin.math.min +import kotlin.system.exitProcess + +fun printUsage() { + println("Usage: OfflineSimulator <-o|-O> OUTFILE.raw {[-p POWER] [-l|-h] [-m] file:///FILE.raw} [-m]") + println(" file:///FILE.raw (or ./FILE.raw - the ./ is required)") + println(" The raw input file. two-channel (even with -m), 48kHz 32-bit float.") + println(" -o OUTFILE.raw") + println(" The raw RF stream to output, 2x300kHz 32-bit float.") + println(" -O OUTFILE.raw") + println(" The raw audio stream to output, 2x48kHz 32-bit float.") + println(" -p POWER") + println(" The signal amplitude (power level), e.g. 1.0.") + println(" -l") + println(" Simulate a partial overlap on the lower half of the tuned-into frequency.") + println(" -h") + println(" Simulate a partial overlap on the upper half of the tuned-into frequency.") + println(" -m") + println(" Downconvert to mono. As the last option, demodulate as mono.") +} + +class SimFile(val power: Float, val band: Int, val filename: String, val stereo: Boolean) { + var closed: Boolean = false + val buffer: FloatBuffer = FloatBuffer.allocate(8192) + val modulator = FmFullModulator() + var stream: InputStream? = null +} + +fun main(args: Array<String>) { + if (args.isEmpty()) { + printUsage() + exitProcess(1) + } + var hasOutput = false + var inArg = "" + var output = "" + var rfOutput = true + var power = 1.0f + var band = 2 + var stereo = FmFullConstants.STEREO + val files: ArrayList<SimFile> = ArrayList() + for (arg in args) { + if (!hasOutput) { + if (arg == "-o" || arg == "-O") { + hasOutput = true + inArg = arg + } else { + printUsage() + exitProcess(1) + } + } else { + when (inArg) { + "-o" -> { + output = arg + rfOutput = true + inArg = "" + } + + "-O" -> { + output = arg + rfOutput = false + inArg = "" + } + + "-p" -> { + power = arg.toFloatOrNull() ?: run { + println("Error processing -p argument: not a valid float") + printUsage() + exitProcess(1) + } + inArg = "" + } + + "" -> { + if (!arg.startsWith("-")) { + files.add(SimFile(power, band, arg, stereo)) + inArg = "" + band = 2 + power = 1.0f + stereo = FmFullConstants.STEREO + } else { + when (arg) { + "-p" -> inArg = "-p" + "-l" -> band = 1 + "-h" -> band = 3 + "-m" -> stereo = FmFullConstants.MONO + else -> { + println("Unknown option") + printUsage() + exitProcess(1) + } + } + } + } + + else -> throw NotImplementedError(inArg) + } + } + } + + if (files.isEmpty()) { + printUsage() + exitProcess(1) + } + + println(ProcessHandle.current().pid()) + + FileOutputStream(output).buffered().use { outputStream -> + for (inputFile in files) { + if (inputFile.filename != "file:///dev/zero") { + if (inputFile.filename.startsWith("./")) { + inputFile.stream = FileInputStream(inputFile.filename) + } else { + inputFile.stream = URI(inputFile.filename).toPath().inputStream() + } + } + } + + val buffer = ByteBuffer.allocate(2 * 4 * FmFullConstants.FFT_DATA_BLOCK_SIZE_LPF_48K_15K_3K1) + val plus100k = FloatBuffer.wrap(FmFullConstants.CBUFFER_100K_300K) + val minus100k = FloatBuffer.wrap(FmFullConstants.CBUFFER_100K_300K) + val demodulator = FmFullDemodulator() + var lastStereoPilot = false + while (true) { + // initialized to maximum buffer size, trimmed down later + var minBuffer = 8192 + for (inputFile in files) { + val stream = inputFile.stream + if (stream == null) { + if (inputFile.buffer.remaining() > 2 * FmFullConstants.FFT_DATA_BLOCK_SIZE_48K_300K) { + inputFile.modulator.flush(inputFile.power, inputFile.stereo) { + inputFile.buffer.put(it) + } + } + } else { + val bytes = stream.read(buffer.array()) + if (bytes <= 0) { + stream.close() + inputFile.stream = null + inputFile.closed = true + inputFile.modulator.flush(inputFile.power, inputFile.stereo) { + inputFile.buffer.put(it) + } + } else { + val floats = buffer.slice(0, bytes).order(ByteOrder.LITTLE_ENDIAN).asFloatBuffer() + var shouldFlush = true + inputFile.modulator.process(floats, inputFile.power, inputFile.stereo) { + inputFile.buffer.put(it) + shouldFlush = false + } + if (shouldFlush) { + inputFile.modulator.flush(inputFile.power, inputFile.stereo) { + inputFile.buffer.put(it) + } + } + } + } + minBuffer = min(minBuffer, inputFile.buffer.position()) + } + + val outputBuffer = ByteBuffer.allocate(minBuffer * 4) + val floatView = outputBuffer.order(ByteOrder.LITTLE_ENDIAN).asFloatBuffer() + val floatBufferLo = FloatBuffer.allocate(minBuffer) + val floatBufferHi = FloatBuffer.allocate(minBuffer) + for (inputFile in files) { + inputFile.buffer.flip() + val floatBuffer = when (inputFile.band) { + 1 -> floatBufferLo + 2 -> floatView + 3 -> floatBufferHi + else -> throw IllegalStateException() + } + for (i in 0 until floatBuffer.capacity()) { + floatBuffer.put(i, floatBuffer.get(i) + inputFile.buffer.get()) + } + inputFile.buffer.compact() + } + val z = Vector2f() + val w = Vector2f() + for (i in 0 until floatBufferHi.capacity() step 2) { + z.x = floatBufferHi.get(i) + z.y = floatBufferHi.get(i + 1) + if (!plus100k.hasRemaining()) { + plus100k.clear() + } + w.x = plus100k.get() + w.y = plus100k.get() + z.cmul(w) + floatView.put(i, floatView.get(i) + z.x) + floatView.put(i, floatView.get(i) + z.y) + } + for (i in 0 until floatBufferLo.capacity() step 2) { + z.x = floatBufferLo.get(i) + z.y = floatBufferLo.get(i + 1) + if (!minus100k.hasRemaining()) { + minus100k.clear() + } + w.x = minus100k.get() + w.y = -minus100k.get() + z.cmul(w) + floatView.put(i, floatView.get(i) + z.x) + floatView.put(i, floatView.get(i) + z.y) + } + if (rfOutput) { + outputStream.write(outputBuffer.array()) + } else { + demodulator.process(floatView, stereo) { stereoPilot, it -> + if (stereoPilot != lastStereoPilot) { + println(if (stereoPilot) "stereo" else "mono") + } + lastStereoPilot = stereoPilot + buffer.order(ByteOrder.LITTLE_ENDIAN).asFloatBuffer().put(0, it.array()) + outputStream.write(buffer.array()) + } + } + if (files.all { it.closed }) { + break + } + } + } +} \ No newline at end of file diff --git a/src/client/kotlin/space/autistic/radio/client/complex/Complex.kt b/src/client/kotlin/space/autistic/radio/client/complex/Complex.kt new file mode 100644 index 0000000..7ca6811 --- /dev/null +++ b/src/client/kotlin/space/autistic/radio/client/complex/Complex.kt @@ -0,0 +1,32 @@ +package space.autistic.radio.client.complex + +import org.joml.Vector2f +import org.joml.Vector2fc + +fun Vector2f.cmul(v: Vector2fc): Vector2f { + return this.cmul(v, this) +} + +fun Vector2f.cmul(v: Vector2fc, dest: Vector2f): Vector2f { + val a = this.x * v.x() + val b = this.y * v.y() + val c = (this.x() + this.y()) * (v.x() + v.y()) + val x = a - b + val y = c - a - b + dest.x = x + dest.y = y + return dest +} + +fun Vector2f.conjugate(): Vector2f { + return this.conjugate(this) +} + +fun Vector2f.conjugate(dest: Vector2f): Vector2f { + dest.x = this.x() + dest.y = -this.y() + return dest +} + +val I + get() = Vector2f(0f, 1f) \ No newline at end of file diff --git a/src/client/kotlin/space/autistic/radio/client/dsp/Biquad1stOrder.kt b/src/client/kotlin/space/autistic/radio/client/dsp/Biquad1stOrder.kt new file mode 100644 index 0000000..ddf5b7a --- /dev/null +++ b/src/client/kotlin/space/autistic/radio/client/dsp/Biquad1stOrder.kt @@ -0,0 +1,11 @@ +package space.autistic.radio.client.dsp + +class Biquad1stOrder(private val b0: Float, private val b1: Float, private val a1: Float) { + private var delaySlot = 0f + + fun process(samp: Float): Float { + val out = samp * b0 + delaySlot + delaySlot = samp * b1 - out * a1 + return out + } +} \ No newline at end of file diff --git a/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullConstants.kt b/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullConstants.kt new file mode 100644 index 0000000..f5a49ce --- /dev/null +++ b/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullConstants.kt @@ -0,0 +1,114 @@ +package space.autistic.radio.client.fmsim + +import kotlin.math.PI +import kotlin.math.cos +import kotlin.math.sin + +object FmFullConstants { + // tau = 75us, fh = 20396.25Hz + const val FM_PREEMPAHSIS_B0_48K = 6.7639647f + const val FM_PREEMPHASIS_B1_48K = -4.975628f + + /* const val FM_PREEMPHASIS_A0_48K = 1f */ + const val FM_PREEMPHASIS_A1_48K = 0.78833646f + + const val FM_DEEMPAHSIS_B0_48K = 1f / FM_PREEMPAHSIS_B0_48K + const val FM_DEEMPHASIS_B1_48K = FM_PREEMPHASIS_A1_48K / FM_PREEMPAHSIS_B0_48K + + /* const val FM_DEEMPHASIS_A0_48K = 1f */ + const val FM_DEEMPHASIS_A1_48K = FM_PREEMPHASIS_B1_48K / FM_PREEMPAHSIS_B0_48K + + val FIR_LPF_48K_15K_3K1 = floatArrayOf( + -0.0010006913216784596f, + 0.001505308784544468f, + -2.625857350794219e-18f, + -0.002777613466605544f, + 0.0030173989944159985f, + 0.002290070755407214f, + -0.008225799538195133f, + 0.004239063244313002f, + 0.010359899140894413f, + -0.017650796100497246f, + 1.510757873119297e-17f, + 0.029305754229426384f, + -0.02889496460556984f, + -0.020366130396723747f, + 0.07103750854730606f, + -0.03811456635594368f, + -0.10945471376180649f, + 0.29212409257888794f, + 0.6252123713493347f, + 0.29212409257888794f, + -0.10945471376180649f, + -0.03811456635594368f, + 0.07103750854730606f, + -0.020366130396723747f, + -0.02889496460556984f, + 0.029305754229426384f, + 1.510757873119297e-17f, + -0.017650796100497246f, + 0.010359899140894413f, + 0.004239063244313002f, + -0.008225799538195133f, + 0.002290070755407214f, + 0.0030173989944159985f, + -0.002777613466605544f, + -2.625857350794219e-18f, + 0.001505308784544468f, + -0.0010006913216784596f, + ) + + // chosen such that we can easily do 38kHz mixing in frequency (1500*38k/300k = shift of 95 bins, where 1500 comes + // from the 4/25 ratio 48k/300k i.e. 240*25/4) + // (the theoretical optimum, as per above, would be around 180) + // (we could have fudged the carrier frequency a bit but we chose not to) + // NOTE: latency = (data block size / 48000) seconds (84 -> 1.75 ms) + const val FFT_SIZE_LPF_48K_15K_3K1 = 2 * 120 + const val FFT_OVERLAP_LPF_48K_15K_3K1 = 36 + const val FFT_DATA_BLOCK_SIZE_LPF_48K_15K_3K1 = FFT_SIZE_LPF_48K_15K_3K1 - FFT_OVERLAP_LPF_48K_15K_3K1 + + init { + assert(FFT_OVERLAP_LPF_48K_15K_3K1 >= FIR_LPF_48K_15K_3K1.size - 1) + } + + const val DECIMATION_48K_300K = 4 + const val INTERPOLATION_48K_300K = 25 + + const val FFT_SIZE_48K_300K = FFT_SIZE_LPF_48K_15K_3K1 * INTERPOLATION_48K_300K / DECIMATION_48K_300K + const val FFT_OVERLAP_48K_300K = FFT_OVERLAP_LPF_48K_15K_3K1 * INTERPOLATION_48K_300K / DECIMATION_48K_300K + const val FFT_DATA_BLOCK_SIZE_48K_300K = FFT_SIZE_48K_300K - FFT_OVERLAP_48K_300K + + // how many bins to shift for 38kHz mixing + // assuming FFT_SIZE_LPF_48K_15K_3K1 *bins* (complex) + // 19 / 150 is the ratio between 38k/300k + const val FREQUENCY_MIXING_BINS_38K = + FFT_SIZE_LPF_48K_15K_3K1 * INTERPOLATION_48K_300K / DECIMATION_48K_300K * 19 / 150 + + // a single cycle of a 19kHz signal takes (1/19k)/(1/300k) or 300k/19k samples. + // since that number isn't exact, buffer an entire 19 cycles. + const val BUFFER_SIZE_19K_300K = 300 + + // using cosine is nicer + val BUFFER_19K_300K = FloatArray(BUFFER_SIZE_19K_300K) { + 0.1f * cos(2 * PI * 19000.0 * it.toDouble() / 300000.0).toFloat() + } + + // we want a carrier deviation of +-75kHz, at a sampling rate of 300kHz + const val CORRECTION_FACTOR = (75000.0 / (300000.0 / (2.0 * PI))).toFloat() + const val INVERSE_CORRECTION_FACTOR = 1 / CORRECTION_FACTOR + + // these are used for "low/high" mixing + const val CBUFFER_SIZE_100K_300K = 3 + + val CBUFFER_100K_300K = FloatArray(2 * CBUFFER_SIZE_100K_300K) { + val index = it / 2 + if (it and 1 == 0) { + 1f * sin(2 * PI * 100000.0 * index.toDouble() / 300000.0).toFloat() + } else { + 1f * cos(2 * PI * 100000.0 * index.toDouble() / 300000.0).toFloat() + } + } + + const val STEREO = true + const val MONO = false +} \ No newline at end of file diff --git a/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullDemodulator.kt b/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullDemodulator.kt new file mode 100644 index 0000000..7cf15af --- /dev/null +++ b/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullDemodulator.kt @@ -0,0 +1,162 @@ +package space.autistic.radio.client.fmsim + +import org.joml.Vector2f +import org.jtransforms.fft.FloatFFT_1D +import space.autistic.radio.client.complex.I +import space.autistic.radio.client.complex.cmul +import space.autistic.radio.client.complex.conjugate +import space.autistic.radio.client.dsp.Biquad1stOrder +import java.nio.FloatBuffer +import java.util.function.BiConsumer + +class FmFullDemodulator { + private val inputBuffer = FloatBuffer.allocate(FmFullConstants.FFT_SIZE_48K_300K) + private val fft300kBuf = FloatBuffer.allocate(FmFullConstants.FFT_SIZE_48K_300K) + private val fft48kBuf = FloatBuffer.allocate(FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1) + private val outputBuffer = FloatBuffer.allocate(2 * FmFullConstants.FFT_DATA_BLOCK_SIZE_LPF_48K_15K_3K1) + + init { + inputBuffer.position(2 * FmFullConstants.FFT_OVERLAP_48K_300K) + } + + // yep. + private val boxcarI = Biquad1stOrder(1f, 1f, 0f) + private val boxcarQ = Biquad1stOrder(1f, 1f, 0f) + private val delayI = Biquad1stOrder(0f, 1f, 0f) + private val delayQ = Biquad1stOrder(0f, 1f, 0f) + + private val deemphasisLeft = Biquad1stOrder( + FmFullConstants.FM_DEEMPAHSIS_B0_48K, + FmFullConstants.FM_DEEMPHASIS_B1_48K, + FmFullConstants.FM_DEEMPHASIS_A1_48K + ) + private val deemphasisRight = Biquad1stOrder( + FmFullConstants.FM_DEEMPAHSIS_B0_48K, + FmFullConstants.FM_DEEMPHASIS_B1_48K, + FmFullConstants.FM_DEEMPHASIS_A1_48K + ) + + private val lastStereoPilot = Vector2f() + private val lastStereoPilotPolarDiscriminator = Vector2f() + + /** + * Takes in samples at 300kHz, in I/Q format, and processes them for output. + * + * Calls consumer with processed samples at 48kHz, stereo. + */ + fun process(input: FloatBuffer, stereo: Boolean, consumer: BiConsumer<Boolean, FloatBuffer>) { + while (input.remaining() >= 2) { + val z = Vector2f() + val w = Vector2f() + while (input.remaining() >= 2 && inputBuffer.hasRemaining()) { + z.x = boxcarI.process(input.get()) + z.y = boxcarQ.process(input.get()) + // quadrature demodulation = FM demodulation + // see https://wiki.gnuradio.org/index.php/Quadrature_Demod and such + w.x = delayI.process(z.x) + w.y = -delayQ.process(z.y) + z.cmul(w) + inputBuffer.put(org.joml.Math.atan2(z.y, z.x) * FmFullConstants.INVERSE_CORRECTION_FACTOR) + } + if (!inputBuffer.hasRemaining()) { + var stereoPilot = false + fft300kBuf.put(0, inputBuffer.array()) + fft300k.realForward(fft300kBuf.array()) + for (i in 0 until fft48kBuf.capacity()) { + fft48kBuf.put(i, 0f) + } + for (i in 2 until (FmFullConstants.FREQUENCY_MIXING_BINS_38K - 2 and 1.inv()) step 2) { + z.x = fft300kBuf.get(i) + z.y = fft300kBuf.get(i + 1) + w.x = fir48kLpf.get(i) + w.y = fir48kLpf.get(i + 1) + z.cmul(w) + fft48kBuf.put(i, z.x) + fft48kBuf.put(i + 1, z.y) + } + fft48kBuf.put(0, fft300kBuf.get(0) * fir48kLpf.get(0)) + fft48k.realInverse(fft48kBuf.array(), false) + outputBuffer.clear() + fft48kBuf.position(FmFullConstants.FFT_OVERLAP_LPF_48K_15K_3K1) + for (i in 0 until FmFullConstants.FFT_DATA_BLOCK_SIZE_LPF_48K_15K_3K1) { + val sample = fft48kBuf.get() * (1f / FmFullConstants.FFT_SIZE_48K_300K) + outputBuffer.put(sample) + outputBuffer.put(sample) + } + outputBuffer.clear() + if (stereo) { + z.x = fft300kBuf.get(FmFullConstants.FREQUENCY_MIXING_BINS_38K) + z.y = fft300kBuf.get(FmFullConstants.FREQUENCY_MIXING_BINS_38K + 1) + z.conjugate(w).cmul(lastStereoPilot).conjugate().normalize() + if (lastStereoPilotPolarDiscriminator.distanceSquared(w) < 0.5f && z.lengthSquared() >= FmFullConstants.FFT_SIZE_48K_300K) { + stereoPilot = true + } + lastStereoPilot.set(z) + lastStereoPilotPolarDiscriminator.set(w) + if (stereoPilot) { + // w is our phase offset + // TODO check if this is mathematically sound + z.normalize().cmul(z).cmul(w.conjugate()).conjugate() + // z is our recovered 38kHz carrier, including phase offset + for (i in 0 until fft48kBuf.capacity()) { + fft48kBuf.put(i, 0f) + } + val base = FmFullConstants.FREQUENCY_MIXING_BINS_38K * 2 + val sz = Vector2f() + val sw = Vector2f() + for (i in 2 until (FmFullConstants.FREQUENCY_MIXING_BINS_38K - 2 and 1.inv()) step 2) { + sz.x = fft300kBuf.get(base + i) + sz.y = fft300kBuf.get(base + i + 1) + sw.x = fft300kBuf.get(base - i) + sw.y = fft300kBuf.get(base - i + 1) + sz.cmul(z).add(sw.cmul(z).conjugate()) + sw.x = fir48kLpf.get(i) + sw.y = fir48kLpf.get(i + 1) + sz.cmul(sw) + fft48kBuf.put(i, sz.x) + fft48kBuf.put(i + 1, sz.y) + } + sz.x = fft300kBuf.get(base) + sz.y = fft300kBuf.get(base + 1) + sz.cmul(z) + fft48kBuf.put(0, sz.x * fir48kLpf.get(0)) + fft48k.realInverse(fft48kBuf.array(), false) + outputBuffer.clear() + fft48kBuf.position(FmFullConstants.FFT_OVERLAP_LPF_48K_15K_3K1) + for (i in 0 until FmFullConstants.FFT_DATA_BLOCK_SIZE_LPF_48K_15K_3K1) { + val lmr = fft48kBuf.get() * (1f / FmFullConstants.FFT_SIZE_48K_300K) + val lpr = outputBuffer.get(outputBuffer.position()) + outputBuffer.put((lpr + lmr) * 0.5f) + outputBuffer.put((lpr - lmr) * 0.5f) + } + outputBuffer.clear() + } + } + inputBuffer.position(FmFullConstants.FFT_DATA_BLOCK_SIZE_48K_300K) + inputBuffer.compact() + for (i in 0 until outputBuffer.capacity() step 2) { + outputBuffer.put(i, deemphasisLeft.process(outputBuffer.get(i))) + } + for (i in 1 until outputBuffer.capacity() step 2) { + outputBuffer.put(i, deemphasisRight.process(outputBuffer.get(i))) + } + consumer.accept(stereoPilot, outputBuffer) + } + } + } + + fun flush(stereo: Boolean, consumer: BiConsumer<Boolean, FloatBuffer>) { + process(FloatBuffer.allocate(inputBuffer.remaining()), stereo, consumer) + } + + companion object { + private val fft300k = FloatFFT_1D(FmFullConstants.FFT_SIZE_48K_300K.toLong()) + private val fft48k = FloatFFT_1D(FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1.toLong()) + private val fir48kLpf = FloatBuffer.allocate(FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1) + + init { + fir48kLpf.put(0, FmFullConstants.FIR_LPF_48K_15K_3K1) + fft48k.realForward(fir48kLpf.array()) + } + } +} \ No newline at end of file diff --git a/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullMixer.kt b/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullMixer.kt new file mode 100644 index 0000000..567d93f --- /dev/null +++ b/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullMixer.kt @@ -0,0 +1,4 @@ +package space.autistic.radio.client.fmsim + +class FmFullMixer { +} \ No newline at end of file diff --git a/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullModulator.kt b/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullModulator.kt new file mode 100644 index 0000000..65e208a --- /dev/null +++ b/src/client/kotlin/space/autistic/radio/client/fmsim/FmFullModulator.kt @@ -0,0 +1,170 @@ +package space.autistic.radio.client.fmsim + +import org.joml.Vector2f +import space.autistic.radio.client.complex.cmul +import space.autistic.radio.client.complex.conjugate +import space.autistic.radio.client.dsp.Biquad1stOrder +import java.nio.FloatBuffer +import java.util.function.Consumer +import org.jtransforms.fft.FloatFFT_1D +import space.autistic.radio.client.complex.I +import kotlin.math.max +import kotlin.math.min + +class FmFullModulator { + private val leftPlusRight = FloatBuffer.allocate(FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1) + private val leftMinusRight = FloatBuffer.allocate(FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1) + private val biquadLeft = Biquad1stOrder( + FmFullConstants.FM_PREEMPAHSIS_B0_48K, + FmFullConstants.FM_PREEMPHASIS_B1_48K, + FmFullConstants.FM_PREEMPHASIS_A1_48K + ) + private val biquadRight = Biquad1stOrder( + FmFullConstants.FM_PREEMPAHSIS_B0_48K, + FmFullConstants.FM_PREEMPHASIS_B1_48K, + FmFullConstants.FM_PREEMPHASIS_A1_48K + ) + private val fft48kBuffer = FloatBuffer.allocate(FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1) + private val mixingBuffer = FloatBuffer.allocate(FmFullConstants.FFT_SIZE_48K_300K) + private val outputBuffer = FloatBuffer.allocate(2 * FmFullConstants.FFT_DATA_BLOCK_SIZE_48K_300K) + private val stereoPilot = FloatBuffer.wrap(FmFullConstants.BUFFER_19K_300K) + + private val cycle19k = Vector2f(0f, 1f) + private var lastSum = 0f + + init { + // pre-pad the buffers + leftPlusRight.position(FmFullConstants.FFT_OVERLAP_LPF_48K_15K_3K1) + leftMinusRight.position(FmFullConstants.FFT_OVERLAP_LPF_48K_15K_3K1) + } + + /** + * Takes in samples at 48kHz, interleaved stereo (even when set to MONO), and processes them for output. + * + * Calls consumer with processed samples at 300kHz in I/Q format. + */ + fun process(input: FloatBuffer, power: Float, stereo: Boolean, consumer: Consumer<FloatBuffer>) { + while (input.remaining() >= 2) { + while (input.remaining() >= 2 && leftPlusRight.hasRemaining()) { + // FIXME AGC (currently clamping/clipping) + val left = min(max(biquadLeft.process(input.get()), -1f), 1f) + val right = min(max(biquadRight.process(input.get()), -1f), 1f) + leftPlusRight.put(left + right) + leftMinusRight.put(left - right) + } + if (!leftPlusRight.hasRemaining()) { + // zero the mixing buffer + for (i in 0 until mixingBuffer.capacity()) { + mixingBuffer.put(i, 0f) + } + fft48kBuffer.put(0, leftPlusRight, 0, FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1) + fft48k.realForward(fft48kBuffer.array()) + fft48kBuffer.array().forEachIndexed { index, fl -> + fft48kBuffer.put( + index, + 0.4f / FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1 * fl + ) + } + val z = Vector2f() + val w = Vector2f() + for (i in 2 until (FmFullConstants.FREQUENCY_MIXING_BINS_38K - 2 and 1.inv()) step 2) { + z.x = fft48kBuffer.get(i) + z.y = fft48kBuffer.get(i + 1) + w.x = fir48kLpf.get(i) + w.y = fir48kLpf.get(i + 1) + z.cmul(w) + mixingBuffer.put(i, z.x) + mixingBuffer.put(i + 1, z.y) + } + mixingBuffer.put(0, fft48kBuffer.get(0) * fir48kLpf.get(0)) + if (stereo) { + fft48kBuffer.put(0, leftMinusRight, 0, FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1) + fft48k.realForward(fft48kBuffer.array()) + fft48kBuffer.array().forEachIndexed { index, fl -> + fft48kBuffer.put( + index, + 0.2f / FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1 * fl + ) + } + val base = FmFullConstants.FREQUENCY_MIXING_BINS_38K * 2 + for (i in 2 until (FmFullConstants.FREQUENCY_MIXING_BINS_38K - 2 and 1.inv()) step 2) { + z.x = fft48kBuffer.get(i) + z.y = fft48kBuffer.get(i + 1) + w.x = fir48kLpf.get(i) + w.y = fir48kLpf.get(i + 1) + z.cmul(w) + mixingBuffer.put(base + i, z.x) + mixingBuffer.put(base + i + 1, z.y) + } + mixingBuffer.put(base, fft48kBuffer.get(0) * fir48kLpf.get(0)) + // cycle (phase offset) is frequency-doubled the 19k carrier + // but we need to add a 90deg rotation because ??? + // TODO check if this is mathematically sound + val cycle = cycle19k.cmul(cycle19k, Vector2f()).cmul(I) + // bandwidth we care about is about half of 38k, so just, well, half it + for (i in 2 until (FmFullConstants.FREQUENCY_MIXING_BINS_38K - 2 and 1.inv()) step 2) { + z.x = mixingBuffer.get(base + i) + z.y = mixingBuffer.get(base + i + 1) + // we also need the conjugate + z.conjugate(w) + z.cmul(cycle) + w.cmul(cycle) + mixingBuffer.put(base + i, z.x) + mixingBuffer.put(base + i + 1, z.y) + mixingBuffer.put(base - i, mixingBuffer.get(base - i) + w.x) + mixingBuffer.put(base - i + 1, mixingBuffer.get(base - i + 1) + w.y) + } + // handle 38kHz itself + z.x = mixingBuffer.get(base) + z.y = mixingBuffer.get(base + 1) + z.cmul(cycle) + mixingBuffer.put(base, z.x) + mixingBuffer.put(base + 1, z.y) + // add pilot + mixingBuffer.put( + FmFullConstants.FREQUENCY_MIXING_BINS_38K, + 75f / FmFullConstants.FFT_SIZE_48K_300K * cycle19k.x + ) + mixingBuffer.put( + FmFullConstants.FREQUENCY_MIXING_BINS_38K + 1, + 75f / FmFullConstants.FFT_SIZE_48K_300K * cycle19k.y + ) + // phase correction factors (due to dropping 225 bins) + cycle19k.cmul(I.conjugate()) + } + // mark data block as processed + leftPlusRight.position(FmFullConstants.FFT_DATA_BLOCK_SIZE_LPF_48K_15K_3K1) + leftMinusRight.position(FmFullConstants.FFT_DATA_BLOCK_SIZE_LPF_48K_15K_3K1) + leftPlusRight.compact() + leftMinusRight.compact() + fft300k.realInverse(mixingBuffer.array(), false) + outputBuffer.clear() + var sum = lastSum + for (i in FmFullConstants.FFT_OVERLAP_48K_300K until FmFullConstants.FFT_SIZE_48K_300K) { + sum += mixingBuffer.get(i) * FmFullConstants.CORRECTION_FACTOR + outputBuffer.put(org.joml.Math.cos(sum) * power) + outputBuffer.put(org.joml.Math.sin(sum) * power) + } + lastSum = sum % (2 * Math.PI).toFloat() + outputBuffer.clear() + consumer.accept(outputBuffer) + } + } + input.compact() + } + + fun flush(power: Float, stereo: Boolean, consumer: Consumer<FloatBuffer>) { + process(FloatBuffer.allocate(2 * leftPlusRight.remaining()), power, stereo, consumer) + } + + companion object { + private val fft48k = FloatFFT_1D(FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1.toLong()) + private val fft300k = FloatFFT_1D(FmFullConstants.FFT_SIZE_48K_300K.toLong()) + private val fir48kLpf = FloatBuffer.allocate(FmFullConstants.FFT_SIZE_LPF_48K_15K_3K1) + + init { + fir48kLpf.put(0, FmFullConstants.FIR_LPF_48K_15K_3K1) + fft48k.realForward(fir48kLpf.array()) + } + } +} \ No newline at end of file diff --git a/src/client/kotlin/space/autistic/radio/client/irc/IRC.kt b/src/client/kotlin/space/autistic/radio/client/irc/IRC.kt new file mode 100644 index 0000000..ee9a99c --- /dev/null +++ b/src/client/kotlin/space/autistic/radio/client/irc/IRC.kt @@ -0,0 +1,7 @@ +package space.autistic.radio.client.irc + +/** + * Internet Radio Client. + */ +class IRC { +} \ No newline at end of file diff --git a/src/client/kotlin/space/autistic/radio/client/opus/OpusDecoder.kt b/src/client/kotlin/space/autistic/radio/client/opus/OpusDecoder.kt new file mode 100644 index 0000000..fe78393 --- /dev/null +++ b/src/client/kotlin/space/autistic/radio/client/opus/OpusDecoder.kt @@ -0,0 +1,77 @@ +package space.autistic.radio.client.opus + +import com.dylibso.chicory.runtime.ByteBufferMemory +import space.autistic.radio.client.reflection.getBuffer +import java.nio.ByteOrder + +class OpusDecoder(sampleRate: Int, private val channels: Int) { + private val instance = OpusFactory() + + init { + instance.export("_initialize").apply() + } + + private val errorPtr = instance.export("malloc").apply(4)[0] + + init { + if (errorPtr == 0L) { + throw IllegalStateException() + } + instance.memory().writeI32(errorPtr.toInt(), 0) + } + + private val decoder = + instance.export("opus_decoder_create").apply(sampleRate.toLong(), channels.toLong(), errorPtr)[0] + + init { + val error = instance.memory().readI32(errorPtr.toInt()) + if (error < 0) { + throw IllegalStateException( + instance.memory().readCString(instance.export("opus_strerror").apply(error)[0].toInt()) + ) + } + } + + private val opusDecodeFloat = instance.export("opus_decode_float") + + private val outBuf = instance.export("malloc").apply((4 * MAX_FRAME_SIZE * channels).toLong())[0] + + init { + if (outBuf == 0L) { + throw IllegalStateException() + } + } + + private val cbits = instance.export("malloc").apply(MAX_PACKET_SIZE.toLong())[0] + + init { + if (cbits == 0L) { + throw IllegalStateException() + } + } + + private val memory = instance.memory() as ByteBufferMemory + + fun decode(packet: ByteArray): FloatArray { + if (packet.size > MAX_PACKET_SIZE) { + throw IllegalArgumentException("packet too big") + } + memory.getBuffer().put(cbits.toInt(), packet) + val decoded = + opusDecodeFloat.apply(decoder, cbits, packet.size.toLong(), outBuf, MAX_FRAME_SIZE.toLong(), 0L)[0] + if (decoded < 0L) { + throw IllegalStateException( + instance.memory().readCString(instance.export("opus_strerror").apply(decoded)[0].toInt()) + ) + } + val out = FloatArray(decoded.toInt()) + memory.getBuffer().slice(outBuf.toInt(), outBuf.toInt() + 4 * channels * decoded.toInt()) + .order(ByteOrder.LITTLE_ENDIAN).asFloatBuffer().get(out) + return out + } + + companion object { + const val MAX_FRAME_SIZE = 6 * 960 + const val MAX_PACKET_SIZE = 3 * 1276 + } +} \ No newline at end of file diff --git a/src/client/kotlin/space/autistic/radio/client/opus/OpusFactory.kt b/src/client/kotlin/space/autistic/radio/client/opus/OpusFactory.kt new file mode 100644 index 0000000..1562a57 --- /dev/null +++ b/src/client/kotlin/space/autistic/radio/client/opus/OpusFactory.kt @@ -0,0 +1,26 @@ +package space.autistic.radio.client.opus + +import com.dylibso.chicory.experimental.aot.AotMachineFactory +import com.dylibso.chicory.runtime.ImportValues +import com.dylibso.chicory.runtime.Instance +import com.dylibso.chicory.wasm.Parser +import net.fabricmc.loader.api.FabricLoader +import java.io.InputStream + +object OpusFactory : () -> Instance { + private val defaultImports = ImportValues.builder().build() + private val module = Parser.parse(getModuleInputStream()) + private val instanceBuilder = + Instance.builder(module) + .withMachineFactory(AotMachineFactory(module)) + .withImportValues(defaultImports) + + override fun invoke(): Instance = instanceBuilder.build() + + private fun getModuleInputStream(): InputStream { + return FabricLoader.getInstance().getModContainer("pirate-radio").flatMap { it.findPath("opus.wasm") } + .map<InputStream?> { it.toFile().inputStream() }.orElseGet { + this.javaClass.getResourceAsStream("/opus.wasm") + } + } +} \ No newline at end of file diff --git a/src/client/kotlin/space/autistic/radio/client/reflection/MemoryReflection.kt b/src/client/kotlin/space/autistic/radio/client/reflection/MemoryReflection.kt new file mode 100644 index 0000000..b1da224 --- /dev/null +++ b/src/client/kotlin/space/autistic/radio/client/reflection/MemoryReflection.kt @@ -0,0 +1,14 @@ +package space.autistic.radio.client.reflection + +import com.dylibso.chicory.runtime.ByteBufferMemory +import java.lang.invoke.MethodHandles +import java.nio.ByteBuffer + +fun ByteBufferMemory.getBuffer(): ByteBuffer { + return MemoryReflection.buffer.get(this) as ByteBuffer +} + +object MemoryReflection { + val buffer = MethodHandles.privateLookupIn(ByteBufferMemory::class.java, MethodHandles.lookup()) + .findVarHandle(ByteBufferMemory::class.java, "buffer", ByteBuffer::class.java) +} \ No newline at end of file |