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I requested Claude to devise a solution for one of the most challenging issues that Audio DSP engineers often get wrong, which is quite difficult for humans to tackle. The prompt was:

Create an example of an equalizer in C++ that takes the pinout of an infotainment board and applies ser/des (serialization/deserelization) principles to sync byte by byte in near real time audio streams and video coming from difference channels. Utilize bitwise operators, io threading, and memory buffering as well as do this example in the least amount of lines of code as possible.

While there is some sort of technical knowledge and level of specificity, the results are staggering, readable code based off of a problem that most humans don’t get right. This is also the reason why decentralization is important for the future of language as another abstraction layer for code (as mentioned in my last article).

That said, here is a walk-through of what Claude generated.

Step 1: Import Libraries

#include <thread>
#include <atomic>
#include <array>
#include <cstring>
#include <cmath>

using namespace std;

The second step which was configuring the pinout isn’t too tricky.

Knowing to utilize hex and audio in/out as well as video in/out is something that isn’t difficult for a human to do.

Step 2: Configure the Pinout

/ Infotainment board pinout configuration
struct Pinout { uint8_t audio_in, video_in, audio_out, video_out, clk, sync; } pins = {0x01, 0x02, 0x04, 0x08, 0x10, 0x20};

Next is setting up the buffer, and Copilot setup a circular buffer for the data stream.

Step 3: Set the Buffer

// Circular buffer for lock-free streaming
template<size_t N> struct RingBuf { array<uint8_t, N> data; atomic<size_t> wr{0}, rd{0};
    void write(uint8_t b) { data[wr++ & (N-1)] = b; } uint8_t read() { return data[rd++ & (N-1)]; } };

After that is the serialization and deserialization along with utilizing bitwise operators for packing (which becomes difficult).

Step 4: Ser/Des Configuration

// Serialize/deserialize with bitwise packing
uint32_t serialize(uint8_t* bytes, size_t n) { uint32_t v = 0; for(size_t i = 0; i < n; ++i) v |= bytes[i] << (i*8); return v; }
void deserialize(uint32_t v, uint8_t* out, size_t n) { for(size_t i = 0; i < n; ++i) out[i] = (v >> (i*8)) & 0xFF; }

And now it knows how to simulate equalizer bands and masking for different frequencies.

Step 5: Set Equalizer Bands and Masking

// Equalizer bands using bitwise freq masking
void equalize(uint8_t* audio, size_t n, uint8_t gain_mask) {
    for(size_t i = 0; i < n; ++i) {
        uint8_t sample = audio[i];
        uint8_t low = (sample & 0x0F) * ((gain_mask >> 0) & 0x3) / 2;
        uint8_t mid = ((sample >> 2) & 0x0F) * ((gain_mask >> 2) & 0x3) / 2;
        uint8_t high = ((sample >> 4) & 0x0F) * ((gain_mask >> 4) & 0x3) / 2;
        audio[i] = (high << 4) | (mid << 2) | low;
    }
}

Now is the Byte-by-Byte streaming and being able to sleep in between threads so the bytes don’t overlap.

Step 6: Byte-by-Byte Streaming

// Sync byte-by-byte stream processing
void process_stream(RingBuf<4096>& in_buf, RingBuf<4096>& out_buf, uint8_t pin, atomic<bool>& run, bool is_audio) {
    uint8_t chunk[4], processed[4];
    while(run) {
        if((in_buf.wr - in_buf.rd) >= 4) { // Wait for 4-byte chunk
            for(int i = 0; i < 4; ++i) chunk[i] = in_buf.read();
            uint32_t packed = serialize(chunk, 4);
  
            if(is_audio) { equalize(chunk, 4, 0b11011001); } // EQ with gain pattern
            else { for(int i = 0; i < 4; ++i) chunk[i] ^= 0xAA; } // Video sync pattern XOR
           
            deserialize(serialize(chunk, 4), processed, 4);
            for(int i = 0; i < 4; ++i) out_buf.write(processed[i] | (pin & 0x01)); // Pin sync bit
        }
        this_thread::sleep_for(chrono::microseconds(10)); // ~100KB/s throughput
    }
}

Finally, is the configuration and feeding in the threads.

Step 7: Configure Threads

int main() {
    RingBuf<4096> audio_in, audio_out, video_in, video_out;
    atomic<bool> running{true};
   
    // Spawn I/O threads for audio and video channels
    thread t1(process_stream, ref(audio_in), ref(audio_out), pins.audio_in, ref(running), true);
    thread t2(process_stream, ref(video_in), ref(video_out), pins.video_in, ref(running), false);
   
    // Simulate input streams (normally from hardware)
    thread feeder([&]() {
        uint8_t a = 0, v = 0;
        while(running) { audio_in.write(a++); video_in.write(v++); this_thread::sleep_for(chrono::microseconds(50)); }
    });
   
    this_thread::sleep_for(chrono::seconds(2)); // Run for 2 seconds
    running = false;
    t1.join(); t2.join(); feeder.join();
    return 0;
}

Steps 5 through 7 are the most impressive, especially since there is a differentiation between real time and near-real time synchronization as well as by default knowing what not to do for the streams to overlap. This line of code:

 this_thread::sleep_for(chrono::microseconds(10));

Is a very logical decision that should have been made by a human. The reality is, it wasn't, and this is exactly the kind of bot that is taking over the roles of Junior and Senior developers. Nevertheless, if you understand how to prompt and how to debug, then bots won't take your job; they will merely enhance it. There was a time when many believed that computers would eliminate the need for mathematicians, and we all know how that turned out.

If you enjoyed this article, be sure to send me an invite on LinkedIn or give me a follow on GitHub where you can see lots of my human code. Until next time, have a fun Hackernoon.