3 files changed, 236 insertions, 0 deletions
diff --git a/Radio/Utils/WaterfallFile/NaiveFFT.swift b/Radio/Utils/WaterfallFile/NaiveFFT.swift
new file mode 100644
index 0000000..79393b7
--- /dev/null
+++ b/Radio/Utils/WaterfallFile/NaiveFFT.swift
@@ -0,0 +1,7 @@
+//
+//  NaiveFFT.swift
+//  PrySDR
+//
+//  Created by Jacky Jack on 05/01/2025.
+//
+
diff --git a/Radio/Utils/WaterfallFile/SimpleImage.swift b/Radio/Utils/WaterfallFile/SimpleImage.swift
new file mode 100644
index 0000000..c05709f
--- /dev/null
+++ b/Radio/Utils/WaterfallFile/SimpleImage.swift
@@ -0,0 +1,116 @@
+//
+//  Image.swift
+//  PrySDR
+//
+//  Created by Jacky Jack on 27/12/2024.
+//
+
+import Foundation
+import AppKit
+
+// https://stackoverflow.com/questions/30958427/pixel-array-to-uiimage-in-swift
+public struct PixelData {
+    var a: UInt8
+    var r: UInt8
+    var g: UInt8
+    var b: UInt8
+}
+
+public class SimpleImage {
+    
+    private var pixels: [PixelData] = []
+    private var width:Int = 0
+    private var height:Int = 0
+    
+    init(width: Int, height: Int) {
+        self.width = width
+        self.height = height
+        pixels = .init(repeating: .init(a: 255, r: 0, g: 0, b: 0), count: width*height)
+    }
+    
+    
+    func drawPalletLine(line: Int, pixelLine:[Float]) {
+        for i in 0..<self.width {
+            var pixel = pixelLine[i]
+            if pixel>256.0 {
+                //print("values to high")
+                pixel = 255.0
+            }
+            if pixel < 0.0 {
+                pixel = 0.0
+            }
+            self.pixels[line*self.width + i].a = 255
+            self.pixels[line*self.width + i].r = UInt8(pixel)
+            self.pixels[line*self.width + i].g = UInt8(pixel)
+            self.pixels[line*self.width + i].b = UInt8(pixel)
+        }
+    }
+    
+    func drawPixel(_ w: Int, _ h: Int, _ pixel: PixelData) {
+        self.pixels[h*self.height+w] = pixel
+    }
+    
+    func toCGImage() -> CGImage? {
+        guard self.width > 0 && self.height > 0 else { return nil }
+        guard self.pixels.count == self.width * self.height else { return nil }
+
+            let rgbColorSpace = CGColorSpaceCreateDeviceRGB()
+            let bitmapInfo = CGBitmapInfo(rawValue: CGImageAlphaInfo.premultipliedFirst.rawValue)
+            let bitsPerComponent = 8
+            let bitsPerPixel = 32
+
+        var data = self.pixels // Copy to mutable []
+            guard let providerRef = CGDataProvider(data: NSData(bytes: &data,
+                                    length: data.count * MemoryLayout<PixelData>.size)
+                )
+                else { return nil }
+
+            guard let cgim = CGImage(
+                width: self.width,
+                height: self.height,
+                bitsPerComponent: bitsPerComponent,
+                bitsPerPixel: bitsPerPixel,
+                bytesPerRow: self.width * MemoryLayout<PixelData>.size,
+                space: rgbColorSpace,
+                bitmapInfo: bitmapInfo,
+                provider: providerRef,
+                decode: nil,
+                shouldInterpolate: true,
+                intent: .defaultIntent
+                )
+                else { return nil }
+
+            return cgim
+    }
+    
+    func toNSImage() -> NSImage? {
+        guard let cgim = toCGImage() else { return nil }
+        return NSImage(cgImage: cgim, size:.zero)
+    }
+    
+    func saveAsJPEG(_ image: NSImage, _ name: String) {
+            if let imageData = image.tiffRepresentation {
+                do {
+                    let bundlePath = Bundle.main.resourcePath!
+                    let imageUrl = URL(fileURLWithPath:bundlePath+"/"+name)
+                    try imageData.write(to: imageUrl)
+                    
+                } catch {
+                    print("Cant save image to disk")
+                }
+                
+            } else {
+                print("cant get tiff representation")
+            }
+    }
+    
+    func saveAsJPEG(_ name: String) {
+        if let img = self.toNSImage() {
+            saveAsJPEG(img, name)
+        }
+    }
+}
+
+
+
+
diff --git a/Radio/Utils/WaterfallFile/main.swift b/Radio/Utils/WaterfallFile/main.swift
new file mode 100644
index 0000000..cf72d56
--- /dev/null
+++ b/Radio/Utils/WaterfallFile/main.swift
@@ -0,0 +1,113 @@
+//
+//  main.swift
+//  WaterfallFile
+//
+//  Created by Jacky Jack on 23/12/2024.
+//
+
+import Foundation
+import Accelerate
+
+print("Read binary file")
+
+let input_filename="rtlsdr_100M_m.cu8"
+
+
+//get data from u8 file
+let dir = getCurrentExecutableDir()
+let filemgr = FileManager.default
+
+if !filemgr.fileExists(atPath: input_filename) {
+    print("Cant find file \(input_filename)")
+    exit(0)
+}
+
+let fileHandle: FileHandle? = FileHandle(forReadingAtPath: dir+"/"+input_filename)
+var i8_arr:[Int8]? = nil
+if let file = fileHandle {
+    file.seek(toFileOffset: 0)
+    do {
+        if let databuf = try file.readToEnd() {
+            
+            print("read \(databuf.count) \(databuf) bytes")
+            //let temp_arr = [Int8](databuf)
+            i8_arr = [Int8](repeating: 0, count: databuf.count)
+            
+            for i in 0..<i8_arr!.count {
+                print(String(format:"%02X", databuf[i]),terminator: "")
+                //convert from 0..255 to -127..128
+                let val = databuf[i]
+                if val <= 127 {
+                    i8_arr![i] = Int8(val)-127
+                } else {
+                    i8_arr![i] = Int8(val-128)
+                }
+                //print(String(format:"%02X", i8_arr![i]),terminator: "")
+            }
+        }
+    } catch {
+        print(error)
+        exit(0)
+    }
+    
+}
+fileHandle?.closeFile()
+
+//all data in buffer lets process data
+//convert all u8 data to float's
+
+//is there other ways to do that?
+/*for i in 0..<dataFloat.count {
+    dataFloat[i] = Float(u8_arr![i])
+}*/
+//will generate 512x512 image
+let sampleCount = 512
+let img = SimpleImage(width: sampleCount, height: sampleCount)
+let number_of_lines = (i8_arr!.count/sampleCount)
+let forwardDCT = vDSP.DCT(count: sampleCount, transformType: .II)!
+var frequencyDomain:[Float] = []
+var transform_result:[Float] = .init(repeating: 0.0, count: sampleCount)
+var dataFloat = [Float](repeating: 0.0, count: sampleCount)
+for i in 0..<sampleCount {
+    let sample_idx = i*sampleCount
+    if i < number_of_lines {
+        let processingSlice = i8_arr![sample_idx...sample_idx+512-1]
+        let processingArray = Array(processingSlice)
+        vDSP.convertElements(of: processingArray, to: &dataFloat)
+        //dataFloat = vDSP.add(127.0, dataFloat)
+        //print(dataFloat)
+        
+        //move from -127.0 to 128.0 range -1.0...1.0
+        //var adjusted = vDSP.divide(dataFloat, Float(sampleCount))
+        var adjusted = dataFloat
+        //print(adjusted)
+        
+        transform_result = forwardDCT.transform(adjusted)
+        transform_result = vDSP.absolute(transform_result)
+        let max = vDSP.maximum(transform_result)
+        //print("max=\(max)")
+        //frequencyDomain.append(contentsOf: transform_result)
+        img.drawPalletLine(line: i, pixelLine: transform_result)
+        //print(transform_result)
+    } else {
+        img.drawPalletLine(line: i, pixelLine: transform_result)
+    }
+    
+}
+
+img.drawPixel(0, 0, PixelData(a: 255, r: 255, g: 0, b: 0))
+img.drawPixel(sampleCount-1, 0, PixelData(a: 255, r: 0, g: 255, b: 0))
+img.drawPixel(0, sampleCount-1, PixelData(a: 255, r: 0, g: 255, b: 0))
+img.drawPixel(sampleCount-1, sampleCount-1, PixelData(a: 255, r: 0, g: 0, b: 255))
+
+
+//print(dataFloat)
+
+
+
+//output data to image file
+img.saveAsJPEG("fft_100m_512.jpeg")
+
+
+
+print("All computations are done")